Heavy Duty Truck Systems by Sean Bennett

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Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 3 9

Overall, the results of this study show that the hybrid solutions studied (HEV and PHEV)
can result in significant gains in reducing greenhouse gases and energy consumption com-
pared with the reference vehicle. The principal factors leading to this variation are:

- for the HEV: the type of use - gains are greater for urban driving than they are for rural
road driving, and limited for motorway driving;

- for the PHEV: the electricity production means and the distance traveled between two
battery charges.

It appears that the energy balance of the plug-in hybrid vehicle may be equivalent to, or
even slightly higher than, that of the reference vehicle (trip 1 in the United States in 2008).
Nonetheless, the evolution of electricity mixes (and associated production technologies)
should result in a reversal of this trend in the coming years.

Figure 7.8
Total primary energy consumption balances for reference (RefV.), hybrid
(HEV), and plug-in hybrid (PHEV) vehicles in trips 1 and 2.

From the point of view of GHG emissions, the deployment of CCS, the construction
of new, more efficient power plants and an increase in the use of renewable energy should
result in a decrease in emissions associated with electricity production. These changes have
been taken into account in the 2030 electricity mixes that we have examined. As for gasoline,
although this study does not consider it, by 2030 we may also expect reductions of well-to-
wheel GHG emissions, primarily from:

- the use of alternative fuels whose well-to-wheel balance is lower than that for the pro-
duction of gasoline from crude oil (biofuels in particular);

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440

- the reduction of flaring during crude oil exploration and production;

- the use of CCS in refining.

Resource diversification is another factor that distinguishes the plug-in hybrid vehicle
from the hybrid electric vehicle and the reference vehicle. In effect, the battery charge net-
work, through the electricity vector, allows for the diversification of primary energy resources
(renewable, nuclear, natural gas, etc.) compared with the hybrid electric vehicle and refer-
ence vehicle, for which oil dependence will remain strong in the coming years.

As noted at the beginning of this chapter, it is important to bear in mind that the conclu-
sions given here cannot be generalized over all environmental impacts. Our analysis, limited
to the evaluation of GHG emissions and energy consumption, should be extended to other
pollutants to ensure that developing electrification of the transport system and introducing
new components does not result in an overall degradation of the associated impacts (e.g.
acidification, eutrophication and toxicity potentials). Such work requires data on the environ-
mental balance of the vehicle that are currently unavailable and difficult to collect, especially
the effects associated with the production of active materials used in the manufacture of
specific components, such as batteries, or the end of life of these components (recycling type,
etc.). In general, considerable uncertainty is associated with the environmental evaluation of
vehicle lifecycle. Consequently, the corresponding results (energy and GHG balances pre-
sented here) need to be qualified as orders of magnitude that reflect the information currently
available. Finally, it is important to consider that, for a plug-in hybrid vehicle that operates
autonomously when running on electricity, a significant reduction in local atmospheric pol-
lution and noise could be obtained under certain driving conditions.

7.2 ECONOMIC BALANCE OF HYBRID ELECTRIC VEHICLES

7.2.1 Factors Included in an Economic Balance of Hybrid Vehicles

Analyzing the costs of alternative drivetrain vehicles, especially those of hybrid vehicles, is
currently a very difficult exercise due to the large number of factors which are still poorly
understood. The market of these vehicles in particular is in full expansion and, apart from a
few Japanese car manufacturers, companies are currently at the research phase or in the pro-
cess of creating their outlets. Publications on this subject are therefore rare, recent, and may
be biased by a communication objective that makes them difficult to understand. In addition,
we observe major disparities on the references considered in the analyses published, espe-
cially regarding the following aspects:

- the time scale considered to commercialize a vehicle; it may vary considerably, extend-
ing practically from today to 2050,

- the production volume scale taken into account; all studies demonstrate that a drop in
cost price is inevitable with high production volumes; we will provide an illustration
of this for batteries below,

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 4 1

- the price reference considered; it may reflect production costs or selling price only,
with margin conditions that, for these innovating technologies, may be quite different
from those generally encountered in mature industries,

- the exchange rate fluctuations; since a large proportion of the studies are made in dol-
lars, the value of the conversion rate chosen has a direct impact on the result (in our
study, we chose a rate of 1.3),

- lastly, from a scientific point of view, since this is a relatively recent subject, very few
articles are available. The economic considerations developed in the following para-
graphs are based on studies conducted by IFP Energies nouvelles and on publications
from various research centers, including as the Argonne National Laboratory and TNO
in particular.

It is therefore important to keep these uncertainties in perspective when assessing any
economic study currently conducted in the field of drivetrain electrification. The figures
published below must be considered in this context. They nevertheless simplify comparisons
between different drivetrains based on the same set of assumptions.

7.2.2 Items Composing the Vehicle Investment Cost

The vehicle investment cost includes all costs involved before delivery to the customer. This
amount includes:

- direct costs related to vehicle manufacturing and in particular:
• price of parts and subsystems manufactured by the car manufacturer or purchased
from a subcontractor,
• vehicle assembly,

- indirect costs which include:
• costs related to the vehicle manufacture but not directly assignable to the vehicle,
such as amortization of the machines,
• costs related to the vehicle sale and distribution,
• warranty costs.

In our analysis, all these costs are reduced to the scale of a vehicle and their respective
shares are calculated with respect to the selling price recommended by the car manufacturer,
generally called the Manufacturer Suggested Retail Price (MSRP). For this analysis, we
chose the vehicle described in Chapter 2, as for the environmental balance. As we will see,
the MSRP of this reference vehicle with its conventional gasoline engine is about €19,120.

7.2.2.1 Evaluation of Direct Costs

Direct costs are composed exclusively of manufacturing costs (also called production costs).
They represent the costs required to produce the vehicle sold by the car manufacturer. Manu-
facturing can be broken down into 5 major items:

- powertrain,
- chassis,

442 Hybrid vehicles

- bodywork and interior equipment,
- assembly, i.e. the labor required to assemble the previous components.

Table 7.10 provides the breakdown of the various direct costs related to manufacturing,
which account for about half of the MSRP, i.e. €9,560.

Table 7.10. Breakdown of reference vehicle manufacturing costs (conventional gasoline engine)
[Vyaseifl/., 2000] and [TNO, 2006]

Cost items Cost in €
Bodywork and interior equipment 3,250
Powertrain 2,170
Chassis 2,140
Assembly 2,000
Total manufacture 9,560

7.2.2.2 Evaluation of Indirect Costs

Indirect costs represent the other half of the MSRP and are broken down as follows:
- indirect production charges (slightly less than 23% of the MSRP) including:
• retirement and health contributions,
• depreciation and amortization of the equipment used,
• research and development (R&D) expenses,
• manufacturer profits,
- sale (slightly less than 23% of the MSRP) which includes:
• distribution costs,
• marketing and advertising,
- the warranty which varies between 4.5% for "traditional" vehicles and 5% of the
MSRP for alternative vehicles such as hybrids [MIT, 2000].

R&D expenses, which represent about 30% of the indirect production charges, are
extremely sensitive data for car manufacturers and it is difficult to obtain an accurate estima-
tion of this cost item for a hybrid vehicle, in particular, which involves far more extensive
studies than for a conventional vehicle. We therefore assumed that these R&D expenses were
amortized over a car manufacturer's entire range and considered that their share increased in
proportion to the number of technologies present in the vehicle, i.e. an increase proportional
to the manufacturing costs.

7.2.2.3 Summary of the Reference Vehicle Investment Costs

For our reference vehicle with conventional gasoline engine, the MSRP amounts to €19,120.
In our example, we therefore have €9,560 from components forming the vehicle and
related to the assembly, and the other half representing the indirect costs related to the car

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 4 3

manufacturer's operation and sale of the vehicle to the end customer. The estimated cost
breakdown can therefore be determined as shown in Table 7.11.

Table 7.11. MSRP breakdown for a vehicle with conventional gasoline engine [Vyas, 2000] and [TNO, 2006]

Cost items Cost in € Cost in %
Manufacture 9,560 50
3,250 13
Bodywork and interior equipment 2,170 12.7
Powertrain 2,140 12.5
Chassis 2,000 11.7
Assembly 4,350 22.75
Indirect production charges 4,350 22.75
Sale 860 4.5
Warranty 19,120 100
Total MSRP 2010

7.2.3 Analysis of Hybrid Vehicle Cost Structure

The purpose of this section is to estimate the purchase price of hybrid vehicles compared
with a similar ICE vehicle. We will therefore use the reference vehicle with its conventional,
hybrid and plug-in hybrid drivetrain versions, described in the previous chapters and whose
main characteristics are summarized in Table 7.12.

Table 7.12. Summary of the main characteristics of the various vehicle configurations studied

Maximum power of Reference Discrete hybrid Plug-in hybrid
the ICE (kW) 80
59 62
Peak power of the 0
electric machine (kW) Gasoline indirect 25 35

Injection no Gasoline indirect Gasoline indirect
no no no
Turbo yes yes
Gasoline
High power battery 3-way catalyzer Li-ion Li-ion

Battery type no 1.3 8
Gasoline
Battery pack nominal 3-way catalyzer Gasoline
energy (kWh) 3-way catalyzer
no
Tank no

After-treatment

Particle filter

444 Hybrid vehicles

7.2.3.1 Internal Combustion Engines

Table 7.13 shows various evaluations of the cost of spark ignition engines (gasoline) based
on the same technology, according to their power. We observe disparities in the expression
of costs, one of the sources displays a cost premium to add to the size cost effect.

Table 7.13. Evaluation of the costs of gasoline internal combustion engines

Costs Volumes Source
€30 /kW no information [Kromer, 2007]
€30 /kW (includes the transmission) no information [WTW, 2008]
€23 /kW > 100,000 units
€22 /kW > 100,000 units [MIT, 2000]
€11.5/kW +€410 current volumes [Graham, 2001]
[Simpson, 2006]

Based on these data, we chose an assumption of €22 /kW which seems to be a fairly rea-
sonable average trend for a gasoline internal combustion engine of between 80 and 100 kW
produced in large volumes. These data generally exclude the 3-way catalyzer depollution
system, for which we have added an all-in cost of €200 according to [WTW, 2008] and [MIT,
2008].

As indicated previously (5.5.1), presence of the electric drivetrain reduces, to a certain
extent, the power required on the ICE. The costs of the ICE for our various vehicles will
therefore amount to €1,760 for the conventional drivetrain and €2,000 and €2,050 for the
hybrid and plug-in hybrid (including a thermal management loop of €700).

7.2.3.2 Electric Drivetrain

The most significant difference between a conventional drivetrain vehicle, whether diesel
or gasoline, and a hybrid drivetrain vehicle is that an electric drive system is added to the
ICE. As described in Chapter 3, several families of electrical machines can be used in road
drivetrains. In practice, however, permanent magnet synchronous machines are by far the
most widely used for passenger cars. Considerable technical knowledge is now available on
electric drivetrains and their no radical variations in their cost are likely over the next few
years, since few technological breakthroughs are to be expected. Manufacturing costs could
nevertheless be reduced through the use of industrial tools adapted to automotive constraints
(volumes, costs, reliability, etc.).

Several studies have already been conducted to understand the costs of the electric
machines and their associated power electronics. The data currently available are provided
in Table 7.14 for AC motors.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 4 5

Table 7.14. Evaluation of the costs of permanent magnet synchronous electric machines

Costs Volumes Source
no information [JRC/Eucar/Conc awe,
€27 /kWpeak 1,000-10,000 units/year
Motor: €18/kWpeak > 100,000 units/year 2008]
Controller: €9 /kWpeak 10,000 units/year then [Lipman, 1999]
100,000 units/year [Cuenca et al., 1999]
€23 /kWpeak + €230
all volumes [Simpson, 2006]
€20.8 /kWpeak
Motor: €6.3/kWpeak [Delucchi, 2000]
Controller: €14.5/kWpeak

€16.7 /kWpeak + 325 (2005)
€12.3 /kWpeak + 300 (long term)

€14.15/kWpeak+ €240
Motor: €8.3 /kWpeak
Controller: €5.85 /kWpeak + €240

The best approach, which acts as reference, is that of the 'Well-To-Wheels " study conducted
by EUCAR, JRC and the CONCAWE [JRC/EUCAR/CONCAWE, 2008]. It gives a kilowatt-
peak at €27 for the machine and power electronics assembly. It is important to note that the per-
manent magnet synchronous machine considered in our study contains a large quantity of rare
earths in its magnets and copper in its windings and that our cost does not take into account the
effect of any tensions which could appear on the market due to depletion of the materials avail-
able caused by high demand or a deliberate policy implemented by certain exporting countries.

On our hybrid vehicle, the 25 kW peak electric machine with its controller corresponds
to an estimated unit cost of €675. For the plug-in hybrid vehicle, the 35 kW peak electric
drivetrain corresponds to an estimated cost of €745.

7.2.3.3 Batteries

While the battery is the major component of all vehicles equipped with an electric drivetrain,
it is also the Achilles' heel. For drivetrains offering an all-electric mode, the vehicle range
under these conditions depends directly on the energy contained in the pack which, in turn,
will govern the mass and volume of the drivetrain as well as a large proportion of the addi-
tional cost to be paid by the consumer in order to drive away in his hybrid vehicle.

In this context, car manufacturers and suppliers have therefore tried to minimize the
quantity of energy to be stored in their battery packs, while retaining the most ambitious
objective possible in terms of consumption. In the long term, the distribution of hybrid vehi-
cles is unlikely to develop massively unless battery performance increases significantly, as
regards the following aspects:

- the purchase price which must be reduced by a factor of 2, 3 or 4 depending on the
announced objectives,

- the lifetime, with an objective of not replacing the battery within the vehicle lifetime.
This criterion could be linked to the previous one to define the notion of battery use cost,

- the performance in terms of energy and power-to-weight.

446 Hybrid vehicles

In addition, evaluating the cost of a battery is extremely difficult due to the very large
number of factors to be considered and assumptions to be made. Apart from the general con-
siderations mentioned at the start of this chapter, other factors must be taken into account to
evaluate the cost announced for the battery:

- the production volume and manufacturing costs depend on the industrial tool set up to pro-
duce them and which can be estimated depending on the maximum annual capacity. Fig-
ure 7.9 shows an example of relative cost variation for two technologies against production
volumes. We observe that the cost of producing lithium batteries would drop by a factor
of nearly 3 for production volumes increasing from 50,000 to 3 million vehicles per year,

- the characterization of the elements, which may be dimensioned for energy or power
depending on the type of application (5.2.6.1). While the cost of a battery in an electric
vehicle is generally expressed with respect to the total energy it contains in €/kWh, for
a power battery in a hybrid vehicle which contains much less energy, being used more
as a power buffer, the cost can be expressed in €/kW-peak. For our plug-in hybrid
vehicle, since its battery characteristics are quite similar to those of an EV, we assumed
that its price could be expressed as a function of its energy, even though some authors
propose formulas involving energy and power [Rousseau, 2009].

Figure 7.9
Graph of Li-Ion and NiMH battery costs against production volumes.
Source: [Kromer and Heywood, 2007]

Furthermore, for a given chemistry, the characterization is very important since it has
a direct impact on the quantity of materials implemented, which represent more than
80% of the total cost of a cell,
the scope taken into account; as previously indicated (4.2.8.2), the architecture of an
onboard energy storage system comprises several levels and some studies indicate a
cost per element, others a cost per module or even a cost for the entire pack with its
management and its thermal conditioning. There is a significant difference since the

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 4 7

cost of the cells represents only 65 to 85% of the total cost of a pack produced indus-
trial in high volumes [Anderman, 2011], [Broussely, 2010],

- the time scale considered, i.e. short, medium or long term. Since materials represent
the greater part of the cost, researchers focus their efforts on this point. There are
two study axes. The first consists in reducing the quantities present in each battery.
The second aims at replacing the most expensive materials, especially at the cathode.
Recent studies have therefore announced cost reductions of about 10% on the price of
battery packs, simply by replacing lithium cobalt oxide, which is very expensive, by
lithium iron phosphate (LiFeP04). Similarly, the cost of the electrolyte and the anode
materials could be reduced by scale effects [Anderson, 2009],

- the reference chosen; for energy, the pack nominal value may be considered, but some
studies consider the usable quantity, which depends on the permitted SOC range, or
even this quantity increased by a factor taking into account the future aging of the ele-
ment. The same applies for the reference power with hybrid vehicles which depends
on numerous factors, as indicated in Chapter 5.

It is therefore not surprising that the costs announced for the onboard battery storage sys-
tems vary considerably from one study to another. Table 7.15 lists various values depending
on the stated assumptions.

Table 7.15. Estimations of battery costs for electrified vehicles

Price in €/kWh Batteries for EV Reference
650 to 1,000 Assumptions [Andermann, 2011]
760 to 940 24 kWh pack, 5,000/year, lifetime 10 years [Burke and Miller, 2010]
500 Boston Consulting for 2010 [Lache ef a/., 2010]
385 Deutsche Bank for 2009 [Syrota and Hirtzman, 2008]
360 to 520 Minimum price [Andermann, 2011]
115 24 kWh pack, 50,000/year, lifetime 10 years [USABC, 2006]
Over 100,000 packs of 40 kWh/year
Price in €/kWh Reference
770 Batteries for PHEV [Howelleia/.,2009]
690 to 770 Assumptions [Burke and Miller, 2010]
630 to 670 3.4 kWh battery - DOE objective for 2009 [Burke and Miller, 2010]
385 Deutsche Bank for 2009 [Howelleia/.,2009]
380 to 460 Current cost, National Academy of Science [Burke and Miller, 2010]
230 3.4 kWh battery - DOE objective for 2012 [Howelleia/.,2009]
292*E+19.2*P Deutsche Bank for 2015 [Rousseau, 2009]
11.6 kWh battery - DOE objective for 2014
Price in €/kW 4 to 12 kWh pack Reference
45 to 50 [Barsacq, 2005]
30 to 35 Batteries for HEV [Barsacq, 2005]
31 Assumptions [Rousseau, 2009]
21 (€580/kWh) 30 kW pack (18 s), 20,000/year [Kromer and Heywood, 2007]
30 kW pack (18 s), 100,000/year
Pack for full hybrid
1 kWh pack for full hybrid (P/E 30), 2030 market

448 Hybrid vehicles

In this context, for the batteries taken into account in our study, we chose assumptions
of €600 /kWh for the onboard battery packs on plug-in hybrid vehicles and €31 /kW for the
battery packs on non plug-in hybrid vehicles.

For our two hybrid vehicles, presence of the battery has no impact on the vehicle MSRPs.
Still reasonable with €910 for the discrete hybrid vehicle, this extra cost reaches €4,800 for
the plug-in hybrid vehicle.

7.2.3.4 Assembly Costs

Adding new components also generates an extra cost on vehicle assembly. This extra cost is
modeled as being proportional to the extra cost of the components added in manufacturing
[Cuencaeia/., 1999].

7.2.3.5 Investment Cost Balance
Table 7.16 provides cost breakdowns for our vehicle equipped with three different drivetrains.

Table 7.16. Comparison of the cost structure of hybrid vehicles with the reference vehicle

Costs items Reference Costs in € Plug-in hybrid
Manufacture 9,560 Discrete hybrid 18,210
3,250 3,250
Bodywork and interior equipment 2,170 12,030 9,020
Powertrain 3,250 2,050
2,140 4,440
Including ICE, thermal 2,000 2,000
management and depollution 4,350
Including electric drivetrain and 4,350 675 945
power electronics
Including high power batteries 860 910 4,800
Charger 19,120 650
Chassis 2,140
Assembly 2,400 2,140
Indirect charges 4,950 4,200
Sale 4,350 6,200
Warranty 1,120 3,900
Total MSRP 2010 22,450 1,470
Extra cost/Reference vehicle (€) 3,330 30,520
Extra cost/Reference vehicle (%) + 18% 11,400
+ 60%

The global balance therefore reaches €12,030 for manufacture, i.e. for the hybrid vehicle,
an MSRP of €22,450 and therefore a vehicle price increase of €3,330, making a difference of
17% compared with the reference ICE vehicle.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 4 9

For the plug-in hybrid vehicle, presence of a bigger battery pack largely accounts for a
higher MSRP of €30,520, i.e. an extra cost of €11,400 (60%) compared with the reference
vehicle.

While our methodology can be used to estimate and compare the cost of the three driv-
etrains on the same vehicle, the exercise is much more difficult for commercialized vehicles.
Some vehicles in fact, such as the Toyota Prius and the Honda Insight, are only available in
hybrid versions. For the others, hybrid vehicles are generally proposed with a set of options
intended either to improve the C 0 2 performance (aerodynamics, rolling, auxiliaries, etc.),
the dynamic performance (4-wheel drive mode), or the interior comfort. In all cases, the aim
is to optimize the feature corresponding to the extra purchase cost of the hybrid vehicle. The
termforcedfeatures is used to express qualitatively the fact that the customer cannot acquire
a hybrid vehicle with basic equipment. The Ford Fusion, for example, is sold in the United
States in various equipment versions with the same drivetrain (Duratec 2.5 L 175 HP) and
the price differences between these versions and the hybrid model range from 13% to 42%,
which confirms the difficulty in evaluating the extra costs related to hybridization.

With the full hybrid drivetrain fitted on our discrete hybrid vehicle, if we compare the
selling prices of mid-segment vehicles, with comparable equipment and a conventional driv-
etrain, the price differences observed with the hybrid version sold range from 18% to 30%.
Our hybrid vehicle, with a simple technological solution, therefore lies in the bottom extra
cost bracket. We must also underline the excellent result obtained by the Toyota Auris whose
hybrid version is only 18% more expensive than the ICE version, while offering a sophisti-
cated technology capable of achieving 89 gC02/km on the European Test Procedure. Lastly,
for comparison, if the Toyota Prius data are applied to our model, we obtain an MSRP of
€26,850, which is very close to the basic price of €26,500 announced by Toyota.

Very few data are available for the plug-in hybrids. If we consider the case of the Opel
Ampera, first vehicle sold in Europe with an announced price in the region of €45,000, our
vehicle seems to be considerably cheaper, which may be explained by a simpler drivetrain
and a battery with half the total energy. As previously, if we apply the data of the Ampera
drivetrain to our cost model, we obtain an MSRP of €44,000, which is therefore quite com-
parable with the value announced by Opel.

7.2.4 Analysis of Hybrid Vehicle Use Cost Structure

The purchase cost is one of the factors taken into consideration by customers of hybrid vehi-
cles, but it may also be worthwhile studying the total cost of ownership of a vehicle in order
to estimate the savings its owner can expect throughout the vehicle lifetime. This informa-
tion is of paramount importance for operators implementing vehicle fleets. This analysis
consists in taking into account not only the purchase of the vehicle but also its use, i.e. its fuel
consumption(s), cost of insurance premiums and maintenance, in other words all expenses
incurred during use throughout its lifetime.

The investment described below includes:

- the purchase price or MSRP,

450 Hybrid vehicles

- purchase incentives corresponding to measures taken in France as part of the Grenelle
Environment Forum, which in 2011 amounted to €2,000 for hybrid vehicles not emit-
ting more than 110 g/km of C 0 2 and €5,000 for plug-in hybrid vehicles whose C 0 2
emissions are less than 60 g/km, according to the European Test Procedure. Since
these incentives were granted over a temporary period in order to launch the market,
we conducted one of the simulations without taking them into account (Figure 7.14),

- resale of the vehicle after 15 years use for 10% of its initial value.

The results presented are based on a discounted calculation of possession over the entire
vehicle lifetime. In this context, a discount rate of 5% per year is used.

7.2.4.1 Maintenance and Insurance Costs

Due to the lack of feedback on the long term use of a large number of hybrid vehicles, it is
difficult to estimate the maintenance costs. For electric vehicles, numerous studies consider
significantly lower maintenance costs due to the simplicity of the drivetrain and recuperative
braking. For hybrid vehicles, we took into account the fact that they are more complex and
less mature than conventional vehicles and have therefore increased their maintenance cost
by a fixed value of 50%.

We considered identical insurance costs for the conventional vehicles and the two hybrid
vehicles.

Consequently, the annual fixed amounts chosen are:
- €600 per year for insurance,
- €600 per year for maintenance of the reference vehicle [Arthaut, 2005] and €900 per

year for the hybrid and plug-in hybrid vehicles.
When necessary, replacement of the battery pack has been included as an investment
expense which occurs at end of life of the initial pack sold with the vehicle.

7.2.4.2 Energy Prices

The comparison was made for two different geographic situations: a French context and an
American context.

A. Regarding Fuel

The main difference on this item concerns taxes. While the price of gasoline at French pumps
includes nearly 60% of various taxes (mostly TIPP (Internal Tax on Petroleum Products) and
VAT), American car drivers pay on average only c$47.4 per gallon i.e. less than c€10 per
liter of taxes at the pump (about 15% taxes). Figure 7.10 shows the differences on the price
of fuel per liter.

Our analysis will be based on an increase in the price of the barrel of oil corresponding
to the median scenario known as the "New Policies" published by the International Energy
Agency with oil costing about $99 /barrel by 2020, then $110 /barrel in 2030 [IEA, 2011].

Chapter 7 · Comparative study ofhybrid vehicles: greenhouse gas emissions, energy consumption,and cost 45

Figure 7.10
Breakdown of the price of gasoline in France and the United States.
Source: IFP Energies nouvelles, from DGEC

B. Regarding Electricity

When estimating the consumptions of the PHEV, we considered that charging would only
be carried out at night. We therefore used an off-peak rate for the economic evaluation. The
price of electricity and its trend has also been simulated between 2010 and 2030. In 2010, the
off-peak rate was €89.3 /MWh and, by 2030, it would be €115 /MWh with our global trend
scenario for energy prices, the barrel costing $110 in this case.

For the United States and in view of the diversity of electricity taxes in the various states,
we assumed that the price of electricity is the same as in France.

We also took into account the additional investment of €750 required to buy a wall-box
(home charging terminal).

Lastly, as a comparison for the plug-in hybrid vehicle in France, the price of energy in
2010 would be €142 /MWh from fuel and €89.3 /MWh from electricity (respectively €184
and€115/MWhin2030).

7.2.5 Evaluation of the Total Cost of Ownership
7.2.5.1 Evaluation of the Use Cost
The total cost of ownership of our two hybrid vehicles was compared with that of the refer-
ence gasoline vehicle. We chose the same use assumptions as for the consumption evaluation
and the LCA analysis described in the previous chapters, i.e. real use cycles, with an annual
average use for the hybrid vehicle and two daily missions for the plug-in hybrid vehicle.

452 Hybrid vehicles
A. Discrete Hybrid Vehicle
For this vehicle, the balance over a period of 15 years, or corresponding to 150,000 km, is
shown on Figure 7.11 in a context of French and American fuel prices (7.3.4.2).

Figure 7.11
Comparison of costs per kilometer for the reference vehicle and the discrete
hybrid vehicle depending on the types of use.
We observe that the higher the cost of fuel, the more advantageous it is to run a hybrid
vehicle compared with a conventional ICE vehicle, with the energy savings compensating
for the extra costs. Using hybrid vehicles on urban profiles also makes more sense since it is
on these profiles that the hybrid vehicle generates the most savings in fuel consumption and
increases the difference compared with the ICE vehicle on the cost per kilometer traveled.
In the French context, the balance also comes down slightly in favor of the hybrid vehicle,
with 4% savings on annual average use, but the choice of a hybrid drivetrain proves highly
relevant in urban use with global savings of about 11%.
Lastly, we note the major impact of maintenance and insurance on the global balance.
For the hybrid vehicle in average French use, the global balance is broken down into 45%
for investment, 20% for fuel and 35% for the related expenses (maintenance and insurance).

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 5 3
B. Plug-in Hybrid Vehicle
We can repeat the same exercise for this vehicle, based on the two daily trips described in
the previous chapters. As with the environmental analysis, the balance is based on these trips
made every day for 15 years, i.e. respectively 120,000 km and 225,000 km traveled and in a
French energy price context. For the distance of 225,000 km, we included for the two hybrid
vehicles the use of two batteries over the 15 years of vehicle ownership. The results shown
on Figure 7.12 call for the following comments:

- the total distances traveled for the two trip assumptions are quite different and the
costs per kilometer reflect this difference directly. However, since the hybrid vehicles
must replace the conventional vehicle on each of its uses, relative comparisons must
be made for each case,

- in terms of global cost, the discrete hybrid is comparable with the conventional vehi-
cle; a result similar to that of Figure 7.11 is obtained,

Figure 7.12
Comparison of cost per kilometer for the reference vehicle, the discrete hybrid
vehicle and the plug-in hybrid vehicle on two typical daily trips.
the plug-in hybrid is also comparable on the shorter trip. Over this daily 40 km distance,
in fact, the nominal 8 kWh battery is used perfectly and the rate of consumption transfer
to electricity reaches 80% (5.5.1). The initial extra purchase cost is offset by the savings

454 Hybrid vehicles
on the energy cost. For the longer trip however, this rate does not exceed 30% and, as a
result, the difference in the price of energy between electricity and fuel no longer offsets
the extra costs. The global difference nevertheless remains very limited, i.e. 6%. It will
obviously increase if the distance traveled between two charges increases.

C. Influence of Battery Lifetime
As mentioned in the introduction to this chapter, the results of these economic balances must
be considered in the light of the degree of uncertainty on the assumptions, which may be very
large. This can be seen in particular on Figure 7.11 with the price of energy, but we can also
consider another highly sensitive factor, the lifetime of the battery used for the PHEV. Fig-
ure 7.13 shows what can happen to the PHEV balance (Figure 7.12 [trip 1]) if we change the
assumption concerning the battery lifetime reducing it from 15 years to 10 or 5 years. In this
case, the battery pack would have to be replaced once or even twice, representing a further
investment cost. The economic balance may become highly unfavorable to the plug-in hybrid
vehicle if the battery lifetime is shortened. In this simulation, we kept the price of €600 /kWh,
irrespective of the battery lifetime. We might expect that, in the future, the progress made in
understanding aging mechanisms will allow us to establish a better relation between battery
cost and lifetime (notion of battery use cost).

Figure 7.13
Influence of battery lifetime on the economic balance of hybrid vehicles com-
pared with the reference vehicle balance.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 5 5
D. Influence of Vehicle Purchase Incentive
We simulated the costs without the €2,000 and €5,000 purchase incentives. We observe the
influence on the investment cost, which is especially high for the PHEV (Figure 7.14).

Figure 7.14
Influence of purchase incentives on the economic balance of hybrid vehicles
compared with the reference vehicle balance.
The PHEV balance will therefore be affected by disappearance of the purchase incentive,
especially if the size of the battery is not adapted to the use that will be made of the vehicle.
As indicated for the LCAs, it is therefore extremely important for the purchaser of a
hybrid vehicle, especially a PHEV, to base his choice on the intended use.
7.2.5.2 Extra Cost/Feature Ratio
Hybridization of drivetrains represents just one alternative amongst a range of technological
or organizational solutions proposed to consumers. While consumers now have a better under-
standing of all the parameters involved in the economic balance concerning the use of their
vehicle (remember the diesel boom in France at the end of the 20th century), they could display
environmental awareness which is somewhat lacking or even be encouraged by voluntarist
local or national policies promoting cleaner technologies (urban tolls, ZAPA areas, etc.).

456 Hybrid vehicles

In this context, hybrid vehicles represent an excellent compromise since, despite a sig-
nificantly higher purchase cost, their total cost of ownership may turn out to be the same as
that of an equivalent ICE vehicle, or very similar in the case of a carefully chosen PHEV. If
we add the positive environmental impact, several tonnes of C02 emissions being avoided
during their use, we could estimate the cost of each tonne of C 0 2 saved. This calculation
is carried out by taking the global balance of C 0 2 emissions for the plug-in hybrid vehicle,
compared with that of the reference vehicle and reduced to the cost difference between these
two vehicles over their entire lifetimes.

We have seen that, for the plug-in hybrid vehicle, the economic balance was not quite as
good as that of the conventional vehicle under current and medium-term foreseeable economic
conditions. While on average a hybrid vehicle can be used at the same price as the reference
vehicle, use of a plug-in hybrid vehicle gives a price per tonne of C02 avoided of about €50
paid for by the plug-in hybrid vehicle owner, in a French context (low-carbon electricity), and
about €100 in a European context with electricity having a less favorable GHG balance. This
cost is obviously still very high if we compare it with that of the C 0 2 market; it could nev-
ertheless be reduced by the effect of local incentive measures. In addition, this cost does not
include the absence of local nuisances (atmospheric pollution, noise, dirt on building walls) that
a PHEV with all-electric range will offer in the urban centers and which could be evaluated.

7.3 SENSITIVE MATERIAL BALANCE FOR ELECTRIFIED VEHICLES

A vehicle is a combination of components but also materials of highly varied origins. Some
are inevitable, others replaceable. They may be common or rare, inexpensive or precious.

A conventional vehicle consists on average of 61% steel, 11% iron and the same proportion
of plastics, less than 5% raw aluminium and about 2% each for alloyed aluminium, copper, glass
and rubber. Hybrid vehicles include other materials such as lithium, nickel and the rare earths
while the proportions of aluminium, glass fibers and platinum increase [Burnham et al, 2006].

To understand the issue regarding the availability of materials, we study their resources
and reserves and how production will satisfy the markets, including that of hybrid vehicles.
Reserves are generally defined as being the readily available stock, i.e. the demonstrated and
profitable quantities of metal, while resources are composed of reserves increased by demon-
strated quantities but not yet profitable, as well as presumed and/or non profitable quantities.

7.3.1 Nickel

According to the USGS [USGS Mineral Commodity Summary Nickel, 2009], world nickel
resources are estimated to be 150 Mt. Close to half ofthem are recoverable and counted as reserves.

From a geographical point of view, 72% of the 70 Mt of nickel reserves are concentrated
in 5 countries: Australia, France (New Caledonia), Cuba, Russia and Canada (figure 7.15).

In 2008, nickel production was 1.6 Mt [USGS Mineral Commodity Summary Nickel, 2009],
with 63% being concentrated in 4 countries: Russia, Canada, Indonesia and Australia (figure 7.16).

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and co4st 57

Figure 7.15
World nickel reserves (total of 70 Mt in 2008).
Source: from USGS

Figure 7.16
Nickel mining production (total of 1.6 Mt in 2008).
Source: from USGS

458 Hybrid vehicles

Given the current production level, the reserves are expected to last about 44 years. Some
projects to extend the mining capacities are already planned and should eventually bring an
additional 0.24 Mt onto the market.

Nickel is mainly used in alloys, especially stainless steels (austenitic stainless steel) (fig-
ure 7.17). It is also used to protect metals more susceptible to corrosion (nickel plating).
Lastly, it is found in nickel metal hydride (NiMH) rechargeable batteries currently equipping
most hybrid vehicles, including those of Toyota. Nickel is also used in the composition of
some refining catalysts.

Figure 7.17

Nickel end uses.
Source: from USGS

Nickel consumption can be expected to rise considerably with the increased market share
of hybrid vehicles, although the transition to lithium batteries already fitted in plug-in hybrid
vehicles but which could also appear on discrete hybrid vehicles could limit this expansion.
Between 3 and 4 kg of nickel per kilowatthour are required to manufacture a nickel-metal-
hydride battery comparable with that of the Toyota Prius [Rade and Andersson, 2000]. To
commercialize 1 million vehicles equivalent to the Toyota Prius, an extra 10,000 t of nickel
would have to be produced, i.e. 0.6% of the current production.

In view of the current mining development perspectives in this sector, this should
not create major tensions and would allow a certain amount of time for prospection
and exploitation of new deposits. Transition to lithium batteries should also help reduce
constraints on nickel.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 5 9

7.3.2 Lithium
In its natural state, lithium is found in the form of chlorides (LiCl) associated with salts of
other alkali metals extracted from the brine of salt lakes, such as the solars in South America
or Tibet where the lithium concentration is considered to be high and may reach from 0.034%
for the Rincon salar in Argentina up to 0.3% for the salt lakes in Chile.

It can also be recovered in the form of silicates, such as spodumene and petalite. It is
mainly found in this form in the United States, Canada, Africa, Russia, China and Australia.
Lithium is also present in trace quantities in seawater (about 0.17 ppm). While the total quan-
tities available are enormous, extraction is currently impossible due to lack of a profitable
recovery process.

Depending on the sources, the total amount of the resources and reserves varies between
14 Mt [USGS Mineral Commodity Summary Lithium, 2009] and 56 Mt of lithium according
to Sociedad Quimica y Minera de Chile, the current leading world producer. Estimated to be
4.4 Mt by the USGS [USGS Mineral Commodity Summary Lithium, 2009], world reserves
of lithium could grow in the future due to new deposits still to be discovered and a certain
number of reserves not currently included.

In terms of geographic dispersion, 68% of the reserves taken into account by the USGS
are located in the salt lakes in Chile. China ranks second with 12% of the volumes, followed
by Bolivia with 7% (figure 7.18). In Bolivia, currently leader in terms of resources, the esti-
mation of reserves is quite incomplete and the figure announced must be taken as a minimum.

Figure 7.18
Distribution of world lithium reserves (total of 4.4 Mt in 2008).
Source: from USGS

460 Hybrid vehicles
In 2008, world lithium production amounted to 27,300 t, with 93% concentrated in

4 countries: Chile, Australia, China and Argentina (figure 7.19). Between 2005 and 2008, it
increased by 28% due to the strong demand for batteries, before a sharp drop in 2009 caused
by the economic crisis.

The reserves currently identified are sufficient to last for 160 years at the current rate of
consumption.

Figure 7.19
World lithium production (total of 27.3 kt in 2008).
Source: from USGS
In recent years, lithium has been mainly used in the battery sector which has experienced
very high growth due to the expansion of mobile telephone and laptop computer markets (fig-
ure 7.20). In 2005, batteries represented 19% of the lithium demand, with this share increas-
ing to 27% in 2008.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and cost 4 6 1

Figure 7.20
Lithium end uses in 2008.
Source: from USGS

In the future, the growth can be expected to come from the automotive sector with the
commercialization of hybrid and electric vehicles equipped with lithium-ion batteries.

The quantities of lithium required to manufacture a Li-ion battery vary considerably
depending on the composition of the electrodes, as explained in Chapter 4.2.6.1. We can
consider that a battery contains an average of 100 g of lithium per kilowatthour of total
energy. An all-electric vehicle equipped with a Li-ion battery of 20 to 30 kWh, for example,
will carry the equivalent of 2 to 3 kg of lithium. According to a study conducted by Merid-
ian International Research, an estimated 8,500 t of produced lithium will be available for
automobile applications by 2020 [Meridian International Research, 2008]. Based on these
quantities, between 3 and 5 million of these EV batteries could be put on the market by 2020,
and even more in case of lower energy batteries which will equip the plug-in hybrid vehi-
cles, like the one we have described. At the same time, while experts consider that abundant
resources of lithium still exist, an understanding of the various types of deposit and their
geological control must be developed in order to guide the prospection of the deposits the
industry will need to expand the electric vehicle fleet on massive scale. Furthermore, once
the market has reached maturity, recycling the lithium from the batteries at end of life should
reduce demand.

The reserves currently identified are sufficient to last for 160 years at the current
rate of consumption and 60% of the resources are not included in the reserves. The
problem of lithium is therefore not related to resources but rather their exploitation
and current geographical concentration.

462 Hybrid vehicles

7.3.3 Rare Earths
The rare earths, or lanthanides, are a group of 17 metals exhibiting fairly similar properties,
for example praseodymium, neodymium, promethium and lutetium. Neodymium is the main
material used in the manufacture of permanent magnets, essential components in electric
motors.

China has the largest resources of rare earths. It operates an estimated deposit of 89 Mt
out of a total of 150 Mt [USGS Mineral Commodity Summary Rare Earths, 2009]. The
proven reserves amount to 99 Mt, with 37% in China. The United States have only 13%
while the former Sovietic bloc controls 19%. Australia, India and Brazil follow (figure 7.21).

Figure 7.21

World reserves of rare earths (total of 99 Mt in 2009).
Source: from USGS

These reserves are in fact sufficient for 800 years at the current consumption rate and it
would seem that the bottleneck will come instead from the production and exchanges of these
materials (figure 7.22).

With the development of hybrid vehicles but also wind turbines, magnets have become
the main market for rare earths (30% of Chinese consumption), well ahead of metallurgy and
petrochemistry (figure 7.23). Hydrogen storage consumes 9% of Chinese production but this
sector could develop in the future if hydrogen and fuel cells live up to their expectations.

Chapter 7 · Comparative study of hybrid vehicles: greenhouse gas emissions, energy consumption, and co4st 63

Figure 7.22
World production of rare earths (total of 124 kt in 2007).
Source', from USGS

Figure 7.23
End uses of rare earths.
Source', from USGS

464 Hybrid vehicles

As we have already seen (3.6), a 60 kW peak power permanent magnet synchronous
electric machine contains about 0.8 kg of magnets; with NdFeB magnets, which are fre-
quently used, this corresponds to a proportion of nearly 30% by weight of rare earths (Nd).
The production of an annual fleet of one million hybrid or electric vehicles equipped with a
60 kW electric machine based on the same technology would result in an annual consump-
tion of about 260 T of rare earths, i.e. close to 0.2% of current world production, which seems
comfortable.

However, the Chinese government obviously intends to take advantage of its leading
position. In August 2009, the Rare Earths Industry Development Plan 2009-2015 [REIDP,
2009] laid the foundations for banning the exports of terbium, dysprosium, yttrium, thulium
and lutetium, and set up an export quota of 35,000 t per year for the other metals, while this
country exported over 54,000 t of rare earths in 2007.

There is no substitute for terbium. Neodymium can be replaced by a cobalt and samar-
ium alloy. Samarium-cobalt magnets are less powerful, however, and more brittle than neo-
dymium magnets. Replacing the second by the first would result in poorer performance and
numerous technologies would have to be reviewed. In addition, samarium is also a rare earth,
the major source being the People's Republic of China. It could be noted that more radical
solutions may be implemented with electric machines requiring no magnet; the car manu-
facturer Renault thus proposes for its electric vehicles wound rotor synchronous machines
(3.2.2.2).

The issue of rare earths could become a major concern in the coming years. The
position of China on this subject and its control of most of the flows of rare earth will
therefore have to be closely monitored for materials with few substitution possibilities.

The future electric vehicle industry can therefore expect an outlook with significant
dependency on a few strategic metals. The criticality of metals such as lithium, nickel
and rare earths will depend on better geological knowledge, the possibility of exploit-
ing resources and the continued efforts aimed at reducing the quantities of materials
required for their various applications. Once again, as elsewhere, research is the key to
the future. The challenge will therefore consist in navigating between substitutions and
struggles to access the materials.

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Abbreviations

°CA Crankshaft rotation angle CCCV Constant Current and
A/C Cabin air conditioning Constant Voltage (charge)
ABS Anti Blocking System CCFA Comité des Constructeurs
AC Alternating current Français d'Automobiles
ACC Advanced Cruise Control CDR Charge Depleting Range
ace Heat Accumulator CEMF Counter Electromotive Force
AER All Electric Range Clim Cabin air conditioning
AGM Absorbed Glass Mat CLU Clutch
ASM Asynchronous machine CP Coupling System
aux (m/e) Auxiliaries (mechanical/ CRE Commission de Régulation
electrical) de l'Énergie
a Angle between the road CSTB Centre Scientifique
and the horizontal plane et Technique du Bâtiment
Beng Internal combustion engine CVT Continuously Variable
state Transmission
BAT Battery Dfuel Engine consumed fuel flow
BDC Bottom Dead Center Direct Current
BDM Backward Dynamic Model DC Direct Current Machine
BJT Bipolar Junction Transistor DCM Dual Clutch Transmission
BLDC BrushLess Direct Current DCT Direction Générale
(machine) DGEC de l'Énergie et du Climat
BMS Battery Management System Depth of Discharge
BQM Backward Quasistatic Model DOD Department of Energy (US)
BSFC Brake Specific Fuel DOE Degree of Freedom
Consumption DoF Dynamic Programmation
cx Aerodynamic drag coefficient DP Discharge Pulse Power
Vehicle cabin DPPC Capability
cab Corporate Average Fuel Dual Shaft Coupling
CAFE Economy DSC Digital Signal Processing
Controlled Auto Ignition DSP Doubly Salient Variable
CAI Centre d'Analyse DSVRM Reluctance Machine
CAS Stratégique Direct Torque Control
DTC Electric Connection
EC

X X Hybrid vehicles

ECDCM DC machine with Electronic FPGA Field Programmable Gate
Commutation Array
FQM Forward Quasistatic Model
ECE (UDC) Urban Driving Cycle FTK Fuel Tank
FTP Federal Test Procedure
ECMS Equivalent Consumption g Gravity acceleration
Minimization Strategy GB Gear Box
GDI Gasoline Direct Injection
EDLC Electric Double Layer GEN Generator
Capacitor GHG
goe Green House Gas
EGR Exhaust Gas Recirculation GVW Gram oil equivalent
HCCI Gross Vehicle Weight
EGR HP High Pressure Exhaust Gas
Recirculation HDV Homogeneous Charge
HEV Compression Ignition
EGRLP Low Pressure Exhaust Gas HIL Heavy Duty Vehicle
Recirculation HOT Hybrid Electric Vehicle
HPPC
EIS Electrochemical impedance Hardware In the Loop
spectroscopy hyb Hybrid Optimization Tool
Hybrid Pulse Power
EM Electric Machine \zt Characterization
Hybrid mode
el Electric Mode ICCT Battery current
International Council on
EMC Electromagnetic ICE Clean Transportation
Compatibility IEA Internal Combustion Engine
IGBT International Energy Agency
EMC Electric Machine and Power Insulated Gate Bipolar
Electronics IISB Transistor
Institutfür Integrierte Systeme
EMCVT Electromagnetic Continously IMA und Bauelementetechnologie
Variable Transmission (Fraunhofer)
IPM Integrated Motor Assist
EMF Electromotive Force IUPAC (manufactured by Honda)
Integrated Power Module
EMPA Swiss Federal Laboratories JRC
for Materials Science and International Union of Pure
Technology and Applied Chemistry
Joint Research Centre -
ENG Internal combustion engine European Commission

EPRI Electric Power Research
Institute

ESP Electronic Stability Program

ESS Energy Storage System

EUDC Extra Urban Driving Cycle

EV Electric Vehicle

exh Exhaust

f Rolling Resistance Coefficient
Fatty Acid Methyl Ester
r Forward Dynamic Model

FAME

FDM

FOC Field Oriented Control

Abbreviations XXI

LCA Life Cycle Analysis MVEG Motor Vehicle Emissions
Group
LED Light Emitting Diode ngb
Gear box ratio
LFP Lithium Fer Phosphate N
NCA Nod
LHV Lower Heating Value
NEDC Lithium Nickel Cobalt
LiFSI Lithium bis(fluorosulfonyl) NGV Aluminum Oxide
imide NGVA
New European Driving Cycle
LiTFSI Lithium bis(trifluoro- NHE
methanesulfonyl)imide NMC Natural Gas Vehicle

LMO Lithium Manganese Oxide NR Natural & bio Gas Vehicle
OBD Association
LMP Lithium Metal Polymer oc, 0
OCV Normal Hydrogen Electrode
LPG Liquefied Petroleum Gas p
Lithium Nickel Cobalt
LTC Low Temperature ace Aluminum Oxide
Combustion
p Non Reversible System
mveh Vehicle mass
aux,e On Board Diagnosis
MC Mechanical Coupling
p Open circuit
MCDCM Mechanical Commutator DC
Machines aux,m Open Circuit Voltage
Pbat
MCPDCM Mechanical Commutator p Losses in engine oil and
Parallel Excitation DC water circuits
Machines clim Electrical auxiliaries power

MCSDCM Mechanical Commutator p Mechanical auxiliaries power
Series Excitation DC dem
Machines Battery power
p
MEEDDM Ministère de l'Ecologie, dem, bat Necessary power to cool the
de l 'Energie, vehicle cabin
du Développement Durable Pech Power demand
et de la Mer
p Power demand at battery
MEP Mean Effective Pressure terminal
em
MON Motor Octane Number Electrochemical power on
Pexh the ESS
MOSFET Metal Oxyde Semi- Electric power of the
conductor Field Effect Pfuel electrical drivetrain
Transistor
p Thermal power in engine
MSRP Manufacturer Suggested exhaust gas
gen
Retail Price Power generated by the fuel

Mtoe Million tons oil equivalent Power provided by the
Generator
MTPA Maximum Torque Per
MTR Ampere
Mechanical Transmission

XXII Hybrid vehicles

p Losses in the electric RPPC Recharge Pulse Power
loss components connecting Capability
the engine to the battery RTE Réseau de Transport
Pit (electric machine, power d'Electricité
electronics and DC/DC Pair Air density
P converter if any) Vehicle frontal surface
r start Power released in the cold SCR Selective Catalytic
sink Reduction
Pth Power threshold for engine SEI Solid Electrolyte Interphase
start SiC Silicon Carbide
PAN Power released in engine SOC State Of Charge
PC water and oil circuits SOH State Of Health
PCM PolyAcryloNitrile Single Shaft Coupling
PF ssc Separated Starter-Generator
PG Personal Computer Space Vector Modulation
PGC SSG Electric machine Torque
PHEV Phase Change Material SVM Internal Combustion Engine
T Torque
PM Particulate Filter Tem Braking torque
PMMA Power Train Torque
Planetary Gear eng Transmission secondary
PMP shaft torque
Planetary Gear Coupling Tfr Top Dead Center
PMSM Toyota Hybrid System
Plug-in Hybrid Electric T domestic Tax on Imported
ppm Vehicle Petroleum Products
PVDF Particulates Matter Tpwt Transmission
PWM Para-Methoxymetham- Battery temperature
PWT phetamine xtx Engine temperatures (water,
R Pontryagin Minimum oil, emission control device)
Principle TDC Connector
Rbat Permanent Magnet THS ESS open circuit voltage
wheel Synchronous Machine TIPP Urban Driving Cycle
Parts per million Urban Dynamometer
RAFST Polyvinylidene fluoride TRA,TX Driving Schedule
RDC Unity Power Factor
Pulse Width Modulation 9bat US Geological Survey
REC Powertrain 9eng Vehicle to Grid
RON Reversible system
Battery internal resistance u
Wheel radius u0

Stoichiometric Air Fuel Ratio UDC
Resolver-to-Digital UDDS
Converter
Heat Recovery System UPF
Research Octane Number USGS
V2G

Abbreviations XXIII

V2H Vehicle to House WRSM Wound Rotor Synchronous
Vbat Battery voltage Machine
Vveh Vehicle speed WTW
VAT Value Added Tax τα Well-To-Wheels
VLMO Voltage Limited Maximum
Output ωβπι Power split ratio
VRLA Valve Regulated Lead Acid œeng Electric Machine speed
VRSM Variable Reluctance œpwt
Synchronous Machine Engine speed
VSC Vehicle Stability Control ωίχ
Transmission speed (wheel
side)

Transmission secondary
shaft speed

List of Authors

François BADIN
PhD in Environmental engineering, University of Chambéry
Engineer from the Institut National des Sciences Appliquées de Lyon
Holder of a national accredation to supervise research (HDR), University of Chambéry
Expert director in the field of hybrid vehicles
(IFP Energies nouvelles, BP 3, 69360 Solaize, [email protected])

Frédérique BOUVART
Engineer from the École Centrale de Marseille
Environmental assessment representative
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

Pierre LEDUC
Engineer from the école Nationale Supérieure de Mécanique et d Aérotechnique de Poitiers
DEA (Fifth year of university studies) in aerodynamics and fluid mechanics, combustion,
heat, University of Poitiers
Project manager - Engines for hybrid vehicles
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

El Hadj MILIANI
PhD in Electrical engineering, University of Franche-Comté, Beifort.
DEA (Fifth year of university studies) in electrical energy processes and processing, École
Nationale Supérieure dÉlectricité et de Mécanique de Nancy (ENSEM)
Engineer, researcher in power electronics
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, el-hadj [email protected])

Valérie SAUVANT-MOYNOT
PhD in Physico-Chemical engineering, Pierre et Marie Curie University, Paris
Engineer from the École Nationale Supérieure de Chimie de Paris (ENSCP)
Head of the electrochemistry and materials department
(IFP Energies nouvelles, BP 3, 69360 Solaize, [email protected])

Antonio SCIARRETTA
PhD in Mechanical engineering, University of L'Aquila (Italy)
Holder of a national accredation to supervise research (HDR), Institut National
Polytechnique de Grenoble
Expert, Tuck Foundation chair on hybrid vehicles and energy management
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

XVIII Hybrid vehicles

Lionel THELLIER
PhD in Structure and dynamics of reactive systems, University of Lille 1
Master Degree in Chemistry, University of Lille 1
Environmental assessment representative
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

YoussefTOUZANI
PhD in Power electronics, Blaise Pascal University, Clermont-Ferrand
Engineer in industrial electronics and DESS (Fifth year of university studies) in industrial
IT, ENSAM (Aix en Provence)
Technical manager of development programs, THALES Avionics
(THALES AES, 78400 Chatou, [email protected])

Franck VANGRAEFSCHÈPE
Engineer from the École Nationale Supérieure de l Aéronautique et de l'Espace (Sup Aéro)
Engineer from IFP School
Project manager in the field of hybrid vehicles
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

Simon VINOT
Engineer from the Ecole Centrale de Lyon
Technico-economic assessment representative
(IFP Energies nouvelles, 92852 Rueil-Malmaison Cedex, [email protected])

Introduction

The fast growth in world population and the associated energy requirements, announced
depletion of fossil fuel resources, the continuing rise in greenhouse gas (GHG) emissions
with induced climatic changes and the increasing atmospheric pollution from conurbations
represent some of the major challenges to be taken up in the next years and decades.

To cope with the energy transition [Rojey, 2008] forced upon us by these challenges, we
must save energy (consume less), reduce our energy intensity (consume better), develop non-
carbon energies and capture and store C02, since fossil energies will probably still be largely
called upon for many years to come to complete the global energy balance: coal and natural
gas for electricity production, oil for transport.

In this context, we will have to take a fresh look at habitat and mobility which are the
largest two items of world's primary energy consumption, with 37% for the residential and
tertiary sector and 26% for transport. It is clear, for example, that the widely dispersed indi-
vidual dwellings which developed in the United States, or even periurban housing in Europe,
generate a demand for mobility which implies use of private transport leading to high energy
consumption. In contrast, a more concentrated habitat reduces the distances to be traveled
and promotes the creation of public transport infrastructures. However, the change to new
ways of life will be long, due in particular to the lifetime of the housing stock, and it will
always be necessary to meet the requirements of individual transport.

Use of private cars for passenger transport can be limited by introducing new types of behav-
ior: carpooling, multimodal approach favoring greater use of public transport, cycling and walk-
ing. Figure 1 illustrates the importance of the mode of transport on energy consumption per
commuter1. For goods transport, apart from the possibility of giving priority to local products or
organizing production systems in order to minimize transport requirements, emphasis must be
placed on alternative routing modes, in particular rail and waterways. As shown on Figure 2, these
modes of transport are much more efficient in terms of energy consumed per tonne transported.

Alongside these actions, the specific consumption of fossil fuels per kilometer and the
associated greenhouse gas emissions must also be reduced, by:

- for the vehicle: reducing the mass, aerodynamic losses and tire losses and improving
the thermal insulation,

- for the auxiliaries: optimizing the efficiency during use,
- for the powertrain: optimizing the efficiency during use,
- for the energy vectors: using powertrains allowing more or less energy consumption

to be transferred to vectors other than hydrocarbons. New energy vectors can therefore
be implemented, for example agrofuels, to retain liquid fuel and conventional engines,
electricity in a plug-in hybrid or electric drive, or even hydrogen in a fuel cell drive.

1. For public transport, the notion of filling rate is also important.

XXVI Hybrid vehicles

Figure 1 Figure 2

Global energy efficiency of modes of commuter trans- Energy efficiency of modes of goods
port in urban and periurban areas, per commuter.km. transport, per tonne.km.
Source: [ADEME, 2008] Source: [ADEME, 2008]

Aware of these stakes, an increasing number of countries are setting up policies aimed
at promoting the use of vehicles with lower greenhouse gas emissions (2020 commitment
on the target value of 95 g/km on European normalized driving cycle) or alternative fuels
(Renewable Energy Directive (RED) and Fuel Quality Directive (FQD) in Europe for exam-
ple). Figure 3 illustrates the C 0 2 emission targets worldwide.

Amongst the solutions mentioned above, this book focuses specifically on hybrid drives,
introduced on the passenger car market in 1997 by Toyota with the first Prius, and which are
now proposed in the ranges of nearly all manufacturers.

As we will see, the concept of hybridization covers a very large number of solutions.
Configurations combining an engine and electric machine(s) are by far the most widely used,
however, especially for passenger cars which represent the main application (if we except the
Hybrid Air full hybrid powertrain recently unveiled by PSA in France).

Hybrid drivetrains reduce the consumption of hydrocarbons, GHG emissions, and even
local nuisances from a vehicle, through the use of more or less complex features based on
electricity in hybrid electric vehicles (HEVs), i.e. 2:

- by being able to stop the engine when the vehicle is stationary rather than allowing it
to idle (Stop-Start),

- by recovering some of the energy available during the braking phases,

2. Drivetrain hybridization includes numerous technological solutions which can be classified accord-
ing to the architecture, the features proposed and even the energy vector(s) used. Readers can refer to
the summary table provided in Appendix 1 to identify and compare these solutions.

Introduction XXVII

Figure 3

C02 emission targets for vehicles sold in various countries (the values have
been corrected to allow comparison with those of the European standard).
Source: from ICCT

- by running the engine closer to its optimum operating conditions,
- by using the vehicle on more or less extended all-electric modes, when use of the

engine would be too penalizing or even prohibited,
- by charging the battery on the grid.

Hybridization therefore typically represents a transition technology allowing the pro-
gressive introduction of electricity in drivetrains to significantly improve the energy and
environmental performance of current vehicles, without radically changing their use typolo-
gies (dynamic performance, range, energy vector), while opening the way to new propulsion
modes for the longer term (plug-in hybrids, fuel cells, electric vehicles).

Hybrid drives form a complex subject requiring a multidisciplinary approach. In this
book, which is intended to be exhaustive, we therefore decided to consider the vehicle, its
components, their association and their control, as well as the global balances determined
over the vehicle lifetime.

The first chapter of this book provides a general presentation of the various conditions of
use of vehicles, to give readers an understanding of the stakes related to the development of
hybrid vehicles and the methods used to compare the performance of the various solutions.

Chapter 2 describes the principles and different types of internal combustion engine.
Chapter 3 then introduces the principles and the different types of electric drives.
Chapter 4 deals specifically with the onboard energy storage systems.
The principles, architectures, specific components and operation of hybrid drives, as well
as the energy management in these vehicles, are developed respectively in Chapters 5 and 6.

XXVIII Hybrid vehicles

Lastly, Chapter 7 provides a global analysis of the various drives, life cycle assessment
(LCA), total costs and availability of sensitive materials.

After consulting this book, readers will be in a position to evaluate the technologies
related to the concept of hybridization, their implementation, balances and generalization
conditions. In view of the information provided, it would appear that no single solution
stands out as representing the future of hybrid drives. A mix of technological solutions, asso-
ciated with various energy vectors, could therefore emerge in the shorter or longer term. To
choose a particular solution, the end user will therefore have to consider numerous aspects
and constraints, including in particular:

- GHG emissions from the vehicle and its energy production pathway(s),

- vehicle purchase and estimated maintenance costs,

- cost(s) and availability of the energy(ies) consumed by the vehicle depending on the
intended type of use,

- local nuisance emissions,

- national and/or local policies promoting and/or restricting the purchase and/or use of
the vehicle,

- estimated vehicle resale conditions.

We can easily understand that this choice is far more complex than the analysis that could
be made by passenger car purchasers, even those familiar with these new technologies. Start-
ing from on this observation, we can expect that, in the short and medium terms, most hybrid
and plug-in hybrid vehicles will be sold to fleets, whose managers will be capable of choos-
ing vehicles that match their intended use, based on all the above criteria.

In the longer term, we can even imagine that the actual notion of private individuals pur-
chasing and owning a vehicle may no longer be the general rule and that future customers
will simply buy a mobility service. This could be the case for long durations, e.g. car rental,
as well as for short journeys with car sharing and, in all cases, creation of very high intermo-
dality so that private vehicles are only used where and when needed.

In this context, the selection and implementation of vehicles will be left up to the opera-
tors, who will capitalize on technological breakthroughs to optimize the choice of drive,
management and vehicle to the service requested by the user. As shown on Figures 4 and 5,
configurations to isolate the chassis and drive from the passenger compartment have already
been proposed, both by big manufacturers such as GM and innovating SMEs such as MUSES
SAS in France. This type of concept will offer the possibility of best adapting the drive and
passenger compartment to the customer's use, for the transport of people or goods, thereby
maximizing the environmental performance and the perspectives of amortizing innovating
drives which, as we will see, remain very expensive.

At the same time, the vehicles of the future must have lower mass (materials, processes)
and less aerodynamic drag, their architecture could be more adapted to their mission by using
2, 3 or 4 wheels depending on the need.

Introduction XXIX

Figure 4

Fuel cell hybrid motorized platform proposed by GM in 2007 in its AUTOnomy
concept.
Source: GM

Figure 5

Mooville all-electric motorized platform with passenger and goods bodies.
Source: MUSES SAS

XXX Hybrid vehicles

Readers will therefore keep in mind that the simplest technological solutions described
in this book, micro- to mild-hybrid, can be directly implemented on vehicles already mar-
keted, and that the most complex, such as plug-in hybrids, can be widely distributed in the
future through innovating vehicle concepts and management systems, most of them still to
be developed.

The hybrid drives discussed in this book can be considered as a transition towards fuel
cell or all-electric drives, with which they share a large number of innovations. This transi-
tion could take a long time, however, since these innovating solutions are all still expensive
and require support from the public authorities to allow the large scale distribution they
absolutely need, especially in view of the fact that specific infrastructures must be created
(electricity, hydrogen).

These technologies will in fact be vital if we are to cope with an ever-increasing demand
for mobility, especially in the emerging countries, with minimum impact from road transport
in terms of greenhouse gas emissions, the Earth's non-renewable resources and the atmos-
pheric pollution in large urban centers.

REFERENCES

ADEME (2008) Efficacités énergétiques et environnementales des modes de transport, synthèse
publique, 30/01/2008.

Rojey A (2008) Énergie et climat - Réussir la transition énergétique. Ed. Technip, 2008 et Rapport du
Comité présidé par Christian de Perthuis : trajectoires 2020-2050 vers une économie sobre en
carbone.

Appendix 1

Summary of the Various
Drivetrain Electrification

Solutions

Figure A1.1

Appendix 2

Equivalence Between Fuel
Consumption and C02
Emissions

Vehicle C 0 2 emissions are measured on a chassis dynanometer according to standards ECE-
R83 and ECE-R101. Measurement is based on sampling the exhaust gases during a test cycle
then analyzing the gases sampled.

Given a few simplifying assumptions, it is nevertheless possible to demonstrate a simple
relation between vehicle fuel consumption and C 0 2 emissions.

On a vehicle, all C 0 2 emissions are produced by combustion of fuel.
Apart from a few (natural gas CH4, methanol CH3OH, ethanol C2H5OH, etc.), fuels are
a mixture of a large number of different compounds. Each one has its own reaction diagram
and it is therefore impossible to write the overall reaction diagram for the combustion of a
fuel such as gasoline.
However, studies are frequently carried out taking a simplified expression of the combus-
tion reaction using an "average" molecule representative of the species present in the mix-
ture. This average molecule, of formula CxHYOz, has no physical reality but is calculated
from the fuel analysis.
For gasoline, the following values are generally taken:
X=7
Y = 1.8.X =12.6
Z = 0 (this value tends to increase with the addition of ethanol in gasoline).
For diesel, the formula generally chosen is C16H28 g.
For this average fuel molecule, the complete stoichiometric combustion equation can be
written as follows:

The mass of fuel consumed in the combustion of one mole of fuel is expressed directly by
the molar mass of the fuel: 12.X + Y + 16.Z

472 Hybrid vehicles

The mass of C02 produced by this combustion is 44.X (44 being the molar mass of C02).
The ratio of these two masses can now be calculated:

This ratio depends only on the average formula of the fuel molecule (and more precisely
the ratios H/C and O/C).

A rapid numerical application can be made: in the example of gasoline and diesel, taking
Y/X =1.8 and Z/X = 0 in both cases, we obtain mC02/mfljel = 3.188.

In other words, the combustion of one kilogram of each fuel will release 3.188 kg of C 0 2
into the atmosphere. If we prefer to speak in terms of liters of fuel (gasoline and diesel have
different densities),

1 liter of gasoline 0.75 kg of gasoline generates 2.39 kg of C 0 2

1 liter of diesel 0.85 kg of diesel generates 2.71 kg of C 0 2

which can also be used to define the equivalences between consumption (in liters per 100 km)
and C 0 2 emissions (in g/km):

1 liter of gasoline per 100 km corresponds to 23.9 g of C 0 2 per km,

1 liter of diesel per 100 km corresponds to 27.1 g of C 0 2 per km.

Appendix 3

Regulation ECE R83 on
Measurement of Pollutant

Emissions«
Regulation ECE R101 on

Measurement of Fuel
Consumption and C02

Emissions

Relation Between ECE Regulations and European Directives

The control of pollutants emission levels (HC, CO, NOx and particulates) from vehicles sold
in Europe began as early as 1970. European Directive n° 70/220/CE of March, 20th 1970 yet
defined homologation tests and maximum levels for emissions of HC and CO. This directive
was amended in the course of years by new ones bringing either modifications in test proce­
dures or evolutions toward lower pollutant emission limits.

European test procedures has been taken at UNECE (United Nations Economic Commis­
sion for Europe) level, an emanation of ECOSOC (ECOnomical and SOcial Council) from
UN, so as to be used by other countries out of European Community.

Scope

Regulation R83 describes the tests to be conducted in order to approve vehicles with regard
to emissions of regulated pollutants (HC, CO, ΝΟχ and particulates). Regulation R101
describes the tests to be conducted to measure consumption of fuel and/or electricity and

474 Hybrid vehicles

C02 emissions of the vehicle. Regulation R101 is more recent and uses tests very similar to
the type 1 tests prescribed by regulation R83.

These two regulations apply:
- to all sparck-ignition Internal Combustion Engine (ICE) and hybrid vehicles (i.e. gaso-

line and similar) having at least 4 wheels,
- to compression-ignition ICE (diesel) and hybrid vehicles of category Mj (carriage of

passengers) or Nj (carriage of goods) having at least 4 wheels and having a maximum
mass of 3,500 kg.

The other vehicles (heavy diesel vehicles, vehicles having 2 or 3 wheels, vehicles having
4 wheels of maximum mass less than 400 kg, vehicles whose maximum speed is less than
50 km/h, vehicles of less than 15 kW whose unladen mass is less than 400 or 550 kg, etc.) are
approved according to another methodology.

Tests Prescribed by Regulation R83

Various tests are conducted to approve vehicles:
- type 1 test: verifying the average exhaust emissions after a cold start (25 °C),
- type 2 test: CO emission with the engine idling,
- type 3 test: emission of crankcase gases,
- type 4 test: evaporation emissions,
- type 5 test: durability of anti-pollution devices,
- type 6 test: verifying the average low ambient temperature CO and HC exhaust emis-
sions after a cold start (- 7 °C),
- OBD (On-Board Diagnosis) test.

Not all vehicles are subjected to the same tests: sparck-ignition ICE and hybrid vehicles
are subjected to all the above tests. Compression-ignition ICE and hybrid vehicles are sub-
jected to type 1, type 5 and OBD tests.

Type 1 Test: Verifying the Average Exhaust Emissions After a Cold Start

The type 1 test is conducted on chassis dynanometer according to the NEDC cycle (see Fig-
ure 1.14) with a certain degree of tolerance in the speed monitoring (± 2 km/h cumulated
with ± 1 s). The chassis dyno is previously adjusted to absorb the same power as the vehicle
losses would do. A deceleration test must therefore be conducted beforehand on flat track
with a vehicle which has already been run-in and driven at least 3,000 km.

The test must be conducted on a cold vehicle (between 20 °C and 30 °C), a conditioning
procedure is required before the test to guarantee measurement repeatability. It consists of
the following steps:

- vehicle driven on chassis dyno (3 consecutive EUDC cycles for sparck-ignition
engined vehicles; 4 ECE cycles + 2 consecutive EUDC cycles for compression-igni-
tion engined vehicles) between 6 and 36 hours before testing;

- soaking for at least 6 hours in a room between 20 °C and 30 °C until there is a difference
of less than 2 °C between the oil and water temperatures and the room temperature;

Appendices 475

- test on NEDC cycle (4 ECE +1 EUDC) conducted from cold start. The vehicle exhaust
gases are diluted in a dilution tunnel (to freeze any chemical reactions) before some
are sampled in bags. The bag content is then analyzed to check whether the vehicle
emissions comply with the prescribed limits.

In addition to stricter limiting values, the limits for the two types of engine (gasoline and
diesel) are scheduled to converge in the next few years. Use of a driving cycle other than the
NEDC is also being considered.

Special case of hybrid vehicles

The type 1 test procedure had to be adapted so that it could be applied to hybrid and plug-
in hybrid vehicles.

The standard identifies 4 categories of hybrid vehicle depending on whether or not:

- they can be charged by plugging-in,
- they are fitted with a switch to choose between various operation modes (ICE only,

electric only, hybrid, sport, etc.).

For non plug-in hybrid vehicles not equipped with a mode switch, the test procedure is the
same as for ICE vehicles, apart from two exceptions:

- preconditioning (before soaking) is longer since it includes at least two complete
NEDC cycles (to eliminate any abnormal battery charging or discharging history),

- greater freedom is allowed concerning the choice of gear engaged, provided that the
car manufacturer has given special instructions in the vehicle user manual and on the
vehicle dashboard (e.g. recommended gear indicator).

For non plug-in hybrid vehicles equipped with a mode switch, the test must be carried out
according to the same procedure as above and in hybrid mode. If the vehicle has several
hybrid modes, the mode selected automatically when the ignition key is switched on must be
used. The technical departments must nevertheless check that the vehicle complies with the
standard in all hybrid modes.

For plug-in hybrid vehicles not equipped with a mode switch, two tests must be conducted:

- test in condition A: battery charged;
- test in condition B: battery discharged.

The test in condition A (battery charged) consists of the following steps:

- battery discharge (by driving the vehicle at a constant speed of 50 km/h or at a lower
speed for which the vehicle operates in electric mode or according to the car manu-
facturer's recommendations) until the ICE starts; the ICE must then be stopped within
10 s,

- vehicle preconditioning (3 EUDC cycles are carried out for vehicles equipped with a
sparck-ignition engine, 4 ECE cycles plus 2 EUDC cycles for vehicles equipped with
a compression-ignition engine),

- thermal conditioning by soaking for at least 6 hours in a room between 20 °C and
30 °C, until there is a difference of less than 2 °C between the engine oil and water
temperatures and the room temperature,

476 Hybrid vehicles

- battery charging while the vehicle is soaking; charging is carried out either with the
vehicle onboard charger or with an external charger recommended by the car manu-
facturer; standard R101 (see p. 480) recommends that the battery should be charged
for 12 hours, unless the onboard instruments indicate that the charge is not complete;
in this case, the maximum charging time allowed is three times the battery nominal
energy (Wh) divided by the grid power; no special charging (trickle, equalization) is
allowed, whether triggered manually or automatically,

- testing with cold start as for a conventional vehicle.

The test in condition B (battery discharged) consists of the following steps:

- vehicle preconditioning (3 EUDC cycles are carried out for vehicles equipped with a
sparck-ignition engine, 4 ECE cycles plus 2 EUDC cycles for vehicles equipped with
a compression-ignition engine),

- battery discharge (by driving the vehicle at a constant speed of 50 km/h or at a lower
speed for which the vehicle operates in electric mode or according to the car manufac-
turer's recommendations) until the ICE starts; the ICE must then be stopped within 10 s,

- thermal conditioning by soaking for at least 6 hours in a room between 20 °C and
30 °C, until there is a difference of less than 2 °C between the engine oil and water
temperatures and the room temperature,

- testing with cold start as for a conventional vehicle.

After each test (condition A and condition B), the measured emissions are compared with
the prescribed limits. In other words, the vehicle must respect the emission limits, irrespec-
tive of the battery state of charge.

Forplug-in hybrid vehicles equipped with a mode switch, the procedure is virtually the same
as for plug-in hybrid vehicles without mode switch, with the following differences:

- the mode is chosen according to Table A3.1 :

Table A3.1. Choice of modes for the tests depending on the modes available on the vehicle.

\ Hybrid modes - Electric only - ICE only - Electric only - Hybrid mode n 1
- ICE only - Hybrid mode m 1
- Hybrid - Hybrid - Hybrid

Battery N. Switch Switch Switch Switch
state of charge^v in position in position in position in position

Condition A Hybrid Hybrid Hybrid Dominant electric
Battery fully hybrid 2
charged

Condition B Hybrid ICE ICE Dominant ICE 3

Minimum state

of charge

1. For example sport, economic, urban mode, etc.
2. Dominant electric hybrid mode: amongst the available hybrid modes, the hybrid mode which has the highest
electricity consumption on a type A test is chosen
3. Dominant ICE hybrid mode: amongst the available hybrid modes, the hybrid mode which has the highest fuel
consumption on a type B test is chosen

Appendices All

- If the vehicle electric range exceeds a complete NEDC cycle, the type A test can be
conducted in all-electric mode if requested by the car manufacturer. In this case, pre-
conditioning is not necessary.

- the battery discharges required depend on the modes available:
• if an all-electric mode is available, discharge is carried out in this mode at 70% ±5%
of the maximum speed that can be reached in all-electric mode for 30 min, or until
one of the following conditions is met:
- a distance of 100 km has been traveled,
- the threshold of 65% of the maximum speed in all-electric mode can no longer be
maintained,
- the onboard instruments indicate to the driver that the vehicle must be stopped,
• if there is no all-electric mode, the battery is discharged in the same way as for a
non plug-in hybrid vehicle (steady speed of 50 km/h until the ICE starts, see above).

Type 2 Test: Verifying CO Emission with the Engine Idling

This test is conducted with warm engine and for all positions of the idling adjustment com-
ponents that could be modified by the user without tools and remaining compatible with an
idling speed reduced by 100 r.p.m. or increased by 250 r.p.m. with respect to the car manu-
facturer's recommended values.

The permitted limiting values of CO concentration per unit volume are:

- 3.5% with the car manufacturer's recommended settings,
- 4.5% within the range of accessible settings.

With this test, the only difference for hybrid vehicles is that operation at idling speed is almost
systematically eliminated. The car manufacturer must therefore plan a spécifie mode accessible
without special instruments to force the engine to run at idling speed for this approval test.

Type 3 Test: Verifying Emission of Crankcase Gases

This test is conducted to check that the crankcase pressure does not exceed atmospheric pres-
sure in each of the following three conditions:

- idling at no load,
- 50 km/h and power absorbed by the chassis dyno corresponding to the bench calibration,
- 50 km/h and power absorbed by the chassis dyno increased by 70%.

If the pressure measurement does not give an acceptable result, a check must be carried out
with a 5 liter bag connected to the dipstick guide tube. The test is considered to be successful if
the bag does not inflate during 5 minutes operation on each of the three above operating points.

Type 4 Test: Determination of Evaporation Emissions from Sparck-
Ignition Engined Vehicles

This test is conducted to measure the fuel vapor emissions that may be emitted by sparck-
ignition engined vehicles during use. The complete procedure is described in Figure A3.1.