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Environmental Entrepreneurs Looks to Electricity for Cars
Jun 29, 2006 (From the CalCars-News archive)
This posting originally appeared at CalCars-News, our newsletter of breaking CalCars and plug-in hybrid news. View the original posting here.
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Environmental Entrepreneurs (E2) is the national community of business people committed to "protecting the environment while building economic prosperity." Without E2's voice and efforts, California's AB 1493 Climate Change (Pavley) Bill would probably not have passed. E2 has repeatedly played a key role nationally and locally on critical issues and legislative campaigns. Any CalCars/PHEV supporter with a business background should consider joining E2's 2000-person network and 600 members from 22 states who work in technology, consulting, venture capital, financial services and other sectors. See for more.

E2 members have been very supportive of CalCars and PHEVs individually for a long time. The article in the June 2006 E2 newsletter is the first time the organization has considered the role of electricity in transportation. (Until now its transportation focus has been largely on hybrids and on the benefits of cellulosic ethanol.)

Importantly, E2 works closely with one of the world's most effective environmental groups, the Natural Resources Defense Council. (Contributions to E2 go to NRDC.) CalCars has been working for a long time to encourage NRDC to become champions of PHEVs. As a member of Set America Free and the Apollo Alliance, NRDC has supported the idea of PHEVs. Roland Hwang, NRDC's Vehicles Policy Director, was involved in they early HEV Working Group efforts that helped fuel the recent advances in PHEVs. Deron Lovaas, NRDC Vehicles Campaign Director, co-authored an Op-Ed on with Set America Free's Gal Luft in April­calcars-news/­375.html and drove CalCars' PHEV when we were in Washington. Senior Attorney Robert F. Kennedy, Jr., has strongly endorsed PHEVs and has featured them on his radio show. NRDC is currently involved in a major research program to quantify PHEVs' overall benefits. We're hoping E2's attention to PHEVs along with efforts by CalCars, Plug-In Partners, legislators and others, will further encourage NRDC to expand its programmatic attention to PHEvs in the coming months.

Following are brief excerpts from a longer article by E2 Co-Founder Bob Epstein and Tony Bernhardt. Please view the full story at­ext/­jsp/­controller?docId=10696 to see the full story, follow URLs and get a sense of the scope of E2 programs. Even from this excerpt you'll see E2 looks at the issue in novel, creative ways.

Will Electricity Challenge Ethanol?

Biomass to Fuels: Grasses like the field of Miscanthus above can create as much as 15 dry tons of biomass per acre. This can be converted into 870 kilowatt-hours of electricity to power a plug-in hybrid or electric vehicle; or into 80 gallons of ethanol to power a flex-fuel vehicle. This article compares the two choices.

Most electric vehicles were removed from the U.S. market when California withdrew the legal requirement to sell zero-emission vehicles in April 2003. It is hard to find former owners of electric vehicles who did not become attached to their cars' noiselessness, lower fuel costs and ability to refuel at home instead of the local gas station.

Ethanol could displace most of our gasoline usage if we solve the technical challenge of making it from plant "biomass" such as agricultural waste, grasses and forest residue (known as cellulosic ethanol), rather than corn. (See Biomass Basics for background.) In our February 2006 newsletter , we described how liquid fuels derived from plant material, like ethanol, can compete with gasoline.

Alternatively, biomass can also be used to produce renewable electricity to power electric vehicles - if more powerful batteries can be developed. If cellulosic ethanol or electric vehicles - or both - become mainstream, the opportunity exists to replace significant amounts of gasoline with fuel derived from biomass.

As President Bush identified in his most recent State of the Union speech, America is addicted to oil. Alternative fuels that use less oil and produce less pollution reduce our dependency on oil, put price pressure on gasoline and diesel, and can reduce global warming pollution.

Electric Vehicle Batteries

Batteries have not been successful as automotive power sources primarily because the amount of energy in a battery is a small fraction of the amount of energy in gasoline. This problem is known as "energy density." To hold the same amount of energy as gasoline, today's vehicular batteries would require over 100 times more space. Current nickel metal hydride (NiMH) batteries hold only about one percent of the "energy density" of gasoline.
An electric vehicle will have much more weight in its batteries than a gasoline-powered vehicle with a full tank of gas. However, an all-electric vehicle avoids the weight of the gasoline motor (an electric motor is much lighter), the transmission and other items.

The issues of weight and efficiency have lead to three design choices: 1. The all-electric vehicle:
2. The hybrid vehicle:
3. The plug-in hybrid: The plug-in hybrid provides a way to charge the battery separately and is both a complete battery-electric vehicle and a gasoline vehicle. More battery is added so the electric driving range of the vehicle is between 20 and 40 miles. (All-electric vehicles usually are designed for a 100 mile range.) For more information about current plug-in hybrids, see CalCars.

The all-electric vehicle and plug-in hybrid vehicles allow us to displace gasoline with electricity. As batteries decrease in price and increase in energy density, electricity could power more - or most - of our vehicles.

How Much Electricity vs. Gasoline is Required per Mile ? Is There a Hybrid Premium?

Using the Toyota Prius as our test case, we can compare its gasoline engine performance to its electric engine performance. The author's car actually gets 44 miles per gallon as measured over the last five years. A modified Prius developed by CalCars running only on battery power requires about 11,400 watt-hours of electricity (this is the equivalent power of 114 one-hundred-watt incandescent light bulbs turned on for one hour - or about 500 compact florescent bulbs) vs. one gallon of gas to travel the same 44 miles.
How Far Can You Drive on a Ton of Biomass?

Both Ethanol and electricity can be produced from biomass. This is done either by using agricultural waste or specific plants such as switch grass, and either converting the energy stored in the cellulose plant cells to ethanol or combusting the dried plant material and converting it to electricity. The question becomes: Which is better?
Thus, one dry ton of biomass will produce: Prius running on electricity Prius running on ethanol 2,700 miles/ton 2,300 miles/ton

In other words, biomass-to-electricity and biomass-to-ethanol produce similar number of miles achievable per ton of biomass. However, there are major differences in feasibility today which will change over time:

  • Biomass-to-electricity and plug-in hybrid technology exists today while the potential of biomass-to-cellulosic ethanol is still unproven in volume.
  • Electricity can be transmitted to every home that an electric vehicle can be plugged in to, compared with the current limited infrastructure for delivering ethanol.
  • The auto companies have sold more than 5 million flex-fuel (ethanol-based) vehicles, but few have announced plans for electric vehicles. GM is rumored to be working on a plug-in hybrid (see GM Eyes Plug-in Hybrid . Toyota is starting to talk about their plug-in hybrid plans (see Toyota to Explore Plug-In Hybrids ).
  • According to the U.S. Department of Energy, advanced technologies for biomass-to-electricity such as gasification could double the electricity produces per ton which would provide 5,400 miles/ton.
  • Market pricing for electricity is relatively independent of oil, while ethanol directly displaces gasoline and, even though its production cost is currently significantly less than that of gasoline, tends to be priced just below gasoline.

How Much Does it Cost to Drive a Mile?

There is considerable savings in buying electricity to charge a battery vs. gasoline in today's market. Using the night time electricity rate of 8.8 cents per kilo-watt hour, the cost to drive is about 2.3 cents/mile. At 44 miles/gallon, this is the equivalent of buying gas at $1.02 per gallon. If a driver recharges during the day, the price is likely to be 50 percent higher or more.

What are the Impacts on Greenhouse Gas Emissions?
If motor fuels go green before power generation goes green the lifecycle GHG emissions of hybrids will be lower than electric vehicles. If power generation goes green first, hybrids will compare unfavorably. In the distant future, when both power generation and motor fuels are green, it won't make a significant difference.


As the U.S. looks to biomass as a renewable source of energy for transportation, two paths hold promise. In one case, the U.S. fleet would comprise increasing numbers of flexible fuel vehicles that can run on gasoline or ethanol. Ethanol production would transition from corn-based to cellulose-based. Alternatively, the U.S. fleet could be increasingly based on electricity, either through plug-in hybrids or all-electric vehicles.

In the first case, the major risk is the ability to produce cellulosic ethanol on a large scale. In the second case, it is the ability to develop higher-energy density batteries. Consumers are likely to find electricity significantly cheaper than ethanol. This is because electricity prices are regulated while ethanol prices are likely to be priced just below gasoline until there is a significant oversupply. E2 believes both paths should be aggressively pursued as they both offer alternatives to oil that will save consumers money and help reduce emissions of greenhouse gases.

Many thanks to E2 member Tony Bernhardt for co-authoring this article. Thanks also go to E2 members Felix Kramer and Ron Lloyd, and to Joe Romm and Brian Jenkins for providing key details. -- Bob Epstein and Nicole Lederer, Editors

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