3.8 Electric and Hybrid Vehicles

An electric vehicle, or EV, is a vehicle with one or more electric motors for propulsion. The energy used to propel the vehicle may be obtained from several sources including on-board generation (using fuel cell technology); onboard rechargeable energy storage systems (battery electric vehicles); direct connection to land based generation plants (trolley buses); and a combination system featuring both an on-board rechargeable energy storage system and a fuelled propulsion power source (internal combustion engine).

In the early part of the 20th century, electric cars and rail transport were commonplace. Electric vehicles were among the earliest automobiles, in use before the advent of the lighter, more powerful internal combustion engines. Over time, their general-purpose commercial use became reduced to specialist roles in platform trucks, forklift trucks, tow tractors, trolley buses and urban delivery vehicles. Electric automobiles re-appeared in the 1990’s. The California Air Resources Board mandated major-automaker sales of EVs, in phases starting in 1998. From 1996 to 1998, GM produced 1117 EV1s, 800 of which were made available through 3-year leases. Chrysler, Ford, GM, Honda, Nissan and Toyota also produced limited numbers of EVs for the California market. GM crushed the EV1’s upon lease expiry. Honda, Nissan and Toyota also repossessed and crushed most of their EVs, which, like the GM EV1s, had been available only by closed-end lease.

Electric motors are mechanically very simple, and release virtually no air pollutants at the place where they are operated. They can also be combined with regenerative braking systems that have the ability to convert/re-cycle movement energy back into stored electricity. Regenerative braking systems can reduce the wear on brake systems and reduce the total energy requirement of a trip, especially in start-and-stop city-use applications. Another advantage is that electric vehicles typically have less vibration and noise pollution than a vehicle powered by an internal combustion engine, whether it is at rest or in motion. Although electric vehicles have few direct emissions, all rely on energy created through electricity generation, which has its own emissions footprint. The US EPA estimates that electric vehicles on a life-cycle basis will reduce GHG emissions by 46.8% relative to gasoline.⁶ The generating emissions were calculated on the national average CO2 output rate for electricity in 2004, based on the EPA eGRID database. Most EV’s use batteries which produce an environmental impact that emanates from their construction, their use and their ultimate disposal. Typically, the battery’s environmental footprint has not been factored into the life-cycle emissions of the transportation fuel.

There are a variety of battery choices, each presenting the user with various combinations of disadvantages including expense, short useful life, range, and significant weight considerations (up to 50% of the total vehicle weight). The efficiency and storage capacity of the current generation of common deep cycle lead acid batteries decreases with lower temperatures, and diverting power to run a heating coil reduces efficiency and range by up to 40%. None of the automakers provided electric demonstration or test vehicles in Canada due to the winter temperatures. Battery and energy storage technology is advancing with improvements to life, weight and range. Costs of the technology are gradually decreasing as the technology matures and production volumes increase.

There currently are no electric vehicles manufactured by the major automakers. EV’s are currently available as neighbourhood electric vehicles (NEVs) and as scooters and bicycles. Several start-up companies, like Tesla Motors, Zenn Motor Company and Phoenix Motorcars, plan to have battery-electric vehicles available to the public in 2008, primarily marketing these vehicles in the South Western United States. A number of small entrepreneurs currently convert gasoline-powered vehicles to battery-electric vehicles. These conversions range in cost from $10,000 to $20,000. The conversions to all electric power do not require EPA certification and are often performed by amateurs.

The last few years have seen the emergence of hybrid electric vehicles. A hybrid electric vehicle (HEV) is a vehicle that combines an internal combustion engine (usually gasoline powered) with an electric motor(s) and an on-board rechargeable energy storage system. The engine powers an electrical generator to either recharge the batteries or directly feed power to an electric motor that drives the vehicle. Modern HEV’s have sophisticated software and hardware to manage the various power functions to optimize fuel consumption as well as recapturing energy through regenerative braking. Most HEV’s reduce fuel consumption and emissions by shutting down the engine at idle and restarting when required. Typically an HEV’s engine is smaller and runs at optimal speeds to capture efficiency.

HEV’s became available to the public in the 1990’s with the introduction of the Honda Insight and Toyota Prius. HEV’s are primarily targeted as urban commuting vehicles for private individuals. Toyota has expanded its offering to the luxury and SUV markets, and Ford has a hybrid Escape on the market. General Motors had a light duty pickup (1500 series) available as a mild hybrid in 2006 and 2007 and is in the process of introducing a number of hybrid vehicles to the market in 2008. Nissan also introduced its Altima hybrid. It is estimated that 180,000 HEV’s were sold in the US in the first half of 2007 or about 3% of car sales during that period.

Plug-in hybrid electric vehicles (PHEV’s) are an extension of HEV logic. These vehicles are capable of carrying a base charge of electricity (charged at home over night for example) and only use traditional fuels when it is necessary to extend the range past the pre-loaded battery-only capacity. GM has unveiled a concept car, the plug-in hybrid Chevrolet Volt, which uses a small internal combustion engine to power an electric generator that in turn, recharges the onboard batteries after the original charge capacity is depleted. As of September 2007, plug-in hybrid (PHEV) electric passenger vehicles are not yet in production. Toyota, General Motors and Ford have announced their intention to introduce production PHEV automobiles. Toyota obtained permission in July 2007 to sell their plug-in Prius in Japan. Aftermarket conversion kits and services are available to convert production model hybrid vehicles (primarily Prius) to PHEV’s that have had plug-in charging added and their electric-only range extended.

Fuel cells used to generate on-board electricity, without the need for battery storage, are still under development and are not yet feasible as a transportation alternative.

Currently there are no hybrid vehicles available that would be suitable for use in the fleet segment that is the focus of this Study. There are no large HEV or PHEV passenger cars, pickups or vans available for commercial fleets. It is anticipated that as platforms are updated and revised power trains are developed, hybrid availability will be expanded to these markets. While HEV’s offer moderately lower tailpipe emissions through reduced gasoline consumption, the life-cycle emissions associated with their use continues to be the subject of continued studies and discussion. If one assumes that the manufacturing footprint for the base automobile is similar, some additions to the emissions footprint for the HEV’s is required to account for the extraction of the primary battery materials (nickel, etc) as well as the disposal of the battery materials once the vehicle is no longer serviceable. Further studies are being done in this area.

⁶ US Environmental Protection Agency – Greenhouse Gas Impacts of Expanded Renewable and Alternative Fuels Use – EPA 420-F-07-035 April 2007