“The potential for grid-connected vehicles to decimate our demand for liquid hydrocarbon fuels should be clear. Freed from the psychological barriers which hinder widespread market acceptance of pure battery electric vehicles, plug-in hybrids with an all-electric capability of just [30] kilometres would slash liquid fuel consumption, since such a high proportion of journeys undertaken are well within this range.”

"Plugged In: The End of the Oil Age” by WWF
(Dr. G. Kendall, 2008)

HEVs / PHEVs Necessary to Meet EU CO2 Targets
The biggest obstacle to the mainstream deployment of HEV and PHEV light duty vehicles is cost. To combine two powertrains within a vehicle is generally more expensive than one powertrain, although electric machines, being mechanically simpler than internal combustion engines (ICE) are cheaper and in hybrids the ICE can be reduced in size (cc) by up to about 45%. This is a complex area of analysis since there are many technological possibilities, a high degree of commercial confidentiality and many competing opinions. The most critical factor does not relate to the ICE engine at all but to the type and size of battery being used. In this context, improvements to ICE technologies need to reduce rather than increase ICE costs.

The Table below provides a cost / benefit analysis of various competing powertrain technologies.

TECHNOLOGY	AV. EFFICIENCY INCREASE	AV. ADDITIONAL COST
ENGINE TECHNOLOGIES
Gasoline E4/E5 – Average EU size = 85kW (source: ACEA Oct 09) Average production cost $14.5 * kW = $1,233 (source: US DOE Jan 09) Average cost of after-treatment = $531 (source: US DOE Jan 09)	0	0
Diesel (E5 DPF) higher engine efficiency due to higher compression ratios and greater energy density of fuel	21%	$1,680
Variable Valve Timing & Lift improve engine efficiency by optimizing the flow of fuel & air into the engine for various engine speeds and inducing Atkinson cycle effect.	5%	$140
Cylinder Deactivation saves fuel by deactivating cylinders when they are not needed.	7.5%	$500
Turbochargers & Superchargers increase engine power, allowing manufacturers to downsize engines without sacrificing performance or to increase performance without lowering fuel economy.	7.5%	$450
Direct Fuel Injection (w/ turbocharging or supercharging) delivers higher performance with lower fuel consumption.	11-13%	$600
TRANSMISSION TECHNOLOGIES
Continuously Variable Transmissions (CVTs) have an infinite number of “gears”, providing seamless acceleration and improved fuel economy.	6%	$215
Libralato Engine – reduction in mechanical complexity from 37 moving engine parts (typical) to four. Reduction in demand for after-treatment. NB: Cost estimate shown is without engine power output downsizing, which would reduce cost further.	30%	-$530

Cost Benefit Analysis of CO2 Powertrain Reduction Technologies¹

These figures are consistent with the findings of Ricardo UK Ltd. as shown in the figure below, which shows that current generation technologies do not exceed 25% efficiency improvements. Particularly in the European context, the figure further below shows that European manufacturers will not be able to meet 2020 legislative requirements without HEV and PHEV technologies.

¹Sources: King Review of Low Carbon Cars 2007, Deutsche Bank: Electric Cars Plugged In Jun 08, NHTSA, www.fueleconomy.gov, PHEV Value Proposition Study Jan 2009 funded by US DOE Vehicle Technologies Programme.
²Source: Ricardo, Dec 2008
³Source: EU Federation T&E, Aug 2009