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Comparing Electric Vehicles: Hybrid vs. BEV vs. PHEV vs. FCEV

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Choosing a vehicle is tough. Sunroof or moonroof? Front wheel drive, rear wheel drive, or all-wheel drive? Do I even need a CD player? And what about color? Burnt orange is nice, but so is cashmere metallic and squid ink (hint: always get squid ink). Considering a hybrid or electric vehicle adds another factor into an already difficult decision. Should you go with a standard hybrid, plug-in hybrid, battery electric, or fuel cell? What is the difference between these types of vehicles anyway?

Conventional Hybrids

Conventional hybrids, like the Toyota Prius, combine both a gasoline engine with an electric motor. While these vehicles have an electric motor and battery, they can’t be plugged in and recharged. Instead their batteries are charged from capturing energy when braking, using regenerative braking that converts kinetic energy into electricity. This energy is normally wasted in conventional vehicles.

Without regenerative braking, cars turn excess speed into heat using brake pads.

Without regenerative braking, cars turn excess speed into heat using brake pads.
Photo Credit: Freewheeling Daredevil.

Depending on the type of hybrid, the electric motor will work with the gasoline-powered engine to reduce gasoline use or even allow the gasoline engine to turn off altogether. Hybrid fuel-saving technologies can dramatically increase fuel economy. For example, the 2014 Honda Accord hybrid achieves a combined 47 miles per gallon (mpg) compared to a combined 30 mpg for the non-hybrid version. At 12,000 miles a year and $4/gallon gasoline, that means saving over $575 each year.

Plug-In Hybrid Electric Vehicles (PHEVs)

Plug-in hybrid electric vehicles (PHEVs) are similar to conventional hybrids in that they have both an electric motor and internal combustion engine, except PHEV batteries can be charged by plugging into an outlet. So why opt for a PHEV instead of a conventional hybrid? Well, unlike conventional hybrids, PHEVs can substitute electricity from the grid for gasoline. The 2014 Ford Fusion Energi, for example, can go about 21 miles by only using electricity, and the 2014 Chevy Volt can go around 38 miles before the gasoline motor kicks in.

Though this doesn’t sound like a far ways, many people drive less than this distance each day. In a recent UCS survey, 54 percent of respondents reported driving less than 40 miles a day. Moreover, using electricity instead of gasoline is cheaper and cleaner for most people. The average cost to drive 100 miles on electricity is only $3.45 compared to $13.52 for driving 100 miles on gasoline.

Battery Electric Vehicles (BEVs)

Battery electric vehicles run exclusively on electricity via on-board batteries that are charged by plugging into an outlet or charging station. The Nissan LEAF, Fiat 500e, and Tesla Model S fall into this category, though there are many other BEVs on the market. These vehicles have no gasoline engine, longer electric driving ranges compared to PHEVs, and never produce tailpipe emissions (though there are emissions associated with charging these vehicles, which UCS has previously examined).

The BEVs on the market today generally go around 60 to 80 miles per charge, though a Tesla can travel over 200 miles on a single charge. A recent UCS survey found that a BEV range of 60 miles would fit the weekday driving needs of 69 percent of U.S. drivers. As battery technology continues to improve, BEV ranges will extend even further, offering an even larger number of drivers the option of driving exclusively on electricity.

This 2014 Mercedes-Benz B-Class offers up to 115 miles of estimated range on a single charge thanks to a battery built by Tesla.

This 2014 Mercedes-Benz B-Class offers up to 115 miles of estimated range on a single charge thanks to a battery built by Tesla.

Fuel Cell Electric Vehicles (FCEVs)

Fuel Cell Electric Vehicles (FCEV) use an electric-only motor like a BEV, but stores energy quite a bit differently. Instead of recharging a battery, FCEVs store hydrogen gas in a tank. The fuel cell in FCEVs combines hydrogen with oxygen from the air to produce electricity. The electricity from the fuel cell then powers an electric motor, which powers the vehicle just like a BEV. And like BEVs, there is no smog-forming or climate-changing pollution from FCEVs tailpipe – the only byproduct is water. Unlike BEVs or PHEVs, however, there is no need to plug-in FCEVs, since their fuel cells are recharged by refilling with hydrogen, which can take as little as 5 minutes at a filling station.

Toyota recently unveiled this 2015 FCEV at the Consumer Electronics Show in Las Vegas.

Toyota recently unveiled this 2015 FCEV at the Consumer Electronics Show in Las Vegas.

But just as producing electricity to charge a plug-in vehicle creates emissions, producing hydrogen also generates emissions. Hydrogen made today from natural gas produces about the same total emissions per mile as charging a plug-in vehicle with electricity generated from natural gas. But when made from renewable sources like biomass or solar power, hydrogen can be nearly emission free.

Moreover, hydrogen fueling infrastructure, like public electric vehicle charging stations, is still ramping up – and mostly available in California. With increased state and federal policies aimed at helping get more of these vehicles on the road, FCEVs can become a large part of our future transportation systems.

Want to learn more about the different types of EVs? Be sure to follow the UCS Clean Vehicles team on The Equation, and also check out our additional background on EVs.

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About the author: Josh Goldman is a policy analyst and leads legislative and regulatory campaigns to help develop and advance policies that reduce U.S. oil use. See Josh's full bio.

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2 Responses

  1. Michael Jeffreson says:

    This analysis is certainly of interest, but perhaps from a scientific point of view, the comparison could be taken a little further.

    A paper published in 2009 in Energy Policy (in the context of this fast moving field admittedly fairly dated) comparing battery electric, hydrogen fuel cell and fuel cell hybrid vehicles found that the drivetrain costs of full FCEVs is around 50% higher than battery electric vehicles, which were in turn 12 times the cost of a conventional ICE drivetrain.

    Assessment of the change in drivetrain cost in the future (2030) saw the FCEV drivetrain cost drop to between 3 and 7 times a ICE drivetrain, the BEV drivetrain dropped to between 2.5 to 6 times the ICE drivetrain cost. So the up front cost hurdle remains significant. An interesting alternative was proposed, a BEV with a hydrogen range extender, allowing for a smaller fuel cell and smaller batteries, seeking an optimized configuration for reducing vehicle weight and cost. The car would still be charged from the grid, as well as fueled with hydrogen when needed. From a capital cost and running cost perspective, this brought the hydrogen option closer to the BEV option. However this partially defeats the main advantage of hydrogen (ready and rapid refuelling and increased range over BEV). Other issues with hydrogen and BEV drivetrains are the availability of key resources: platinum in the case of hydrogen fuel cells, and lithium in the case of BEVs. If these vehicles are ramped up to significant production volumes, these resources may be challenged. This reinforces the need to consider options where large battery packs and large fuel cells are not necessary (ie. lighter, more range limited vehicles).

    The findings in regard to efficiency indicated that an electric system would deliver 1013 miles per GJ, hydrogen 506 miles per GJ, and conventional fuel 253 miles. With projected fuel costs at $28.50 per GJ for conventional fuel, $35 GJ for hydrogen and $36 GJ for electricity, the battery electric solution has lifecycle costs 1.75 times better than either conventional drivetrains or hydrogen vehicles, in the longer term.

    These findings are to be expected in relation to hydrogen systems. Converting gas to hydrogen, or producing it through power inputs, storing it, transporting it to a newly created fueling infrastructure, pumping it into a car with a specially designed tank, then converting it to electricity in a fuel cell to drive an electric drivetrain that is functionally identical to a BEV, is always going to be an inefficient way of using energy. The BEV takes power directly from the grid using an existing and pervasive ‘refuelling infrastructure’ to charge batteries to drive the electric drivetrain. This is clearly more efficient.

    However BEV vehicles have several problems, particularly the weight of batteries, the environmental costs of producing and disposing of them, the time to charge batteries, the limitations on range, and the issue of range reduction over time. Early indicators are that BEVs can lose up to 20% of their range after 100,000 km of use. This may be acceptable where the required range of the vehicle for commuter use is limited, and there is a surplus of range when the car is new, but it may become a problem if the vehicle is operated at the edge of its range capacity.

    These issues of battery degradation are not evident in applications where the batter is not pushed to its limits, as in a hybrid electric vehicle. Here, the conservative charging range of the battery enables the battery life to match the practical lifespan of most vehicles.

    Where is all this heading? Without breakthroughs in either hydrogen or BEVs, we may need to accept two tiers of vehicles, those with limited range for city use, and those for longer range use. Ideally, we would start to accept that limited range BEVs could be supplemented by wider usage of rail and other public transport options for longer range travel, and start putting more money into these areas, rather than highly capital intensive exercises such as hydrogen production and fueling infrastructure.

  2. FCV can be use as a power generator to supply home use for 7 days. This become very useful for US and China which suffer frost bite that might cause large scale power down.

    Wong