Slashdot Mirror

← Back to Stories (view on slashdot.org)

White House Wants 1M Electric Cars By 2015

Posted by Soulskill on from the way-too-many-and-yet-way-too-few dept.

coondoggie writes "The White House has outlined a wide-ranging plan for putting one million of what it calls 'advanced technology vehicles' on the road by 2015. Most observers would say that is a good start, but is it reasonably doable? The next White House budget will include a number of investments and enticements to make the goal achievable in theory. Of course, not all of the provisions are likely to make the cut."

1 of 603 comments (clear)

  1. Re:Plug In Cars by Solandri · · Score: 5, Informative

    A gallon of gas is equivalent to ~34kWh of electricity. At the relatively cheap rate of 10 cents per kWh, that means $3.40 in electricity costs to replace a gallon of gas. Plugging in seems to have no price advantage over filling up, and has the extra problems of range and charge time.

    The difference is in energy conversion efficiency. An internal combustion engine is about 25% efficient. Add in mechanical losses and gasoline refining/transport costs and you're at about 15% of the energy from the oil that comes out of the ground to drive the wheels of your car.

    Electricity has about 40% efficiency from a coal plant (higher for nuclear and renewables), 95% transmission efficiency to a person's house, and about 80% for battery conversion and electric motor efficiency. So overall about 30% of the energy from the coal drives the wheels of your car. Roughly twice as efficient as an ICE. Also note that the price you pay per kWh already takes into account the losses from the first two steps. So on a $ per mile basis, electric is about 5x cheaper than an ICE, assuming $3.40/gal gas.

    The same reason is why hydrogen generated from electrolysis is a dead end as a fuel. You're talking about 40% efficiency from coal plant to electricity, and (optimistically) 65% efficiency from electrolysis, then 70% for a hydrogen fuel cell, and 95% electric motor efficiency. Overall you're at 17% of the coal's energy driving your car's wheels, which is pretty much the same as existing ICE vehicles. Factor in the storage and transport problems along with lack of infrastructure, and hydrogen is worse than oil. It only becomes viable if we can get nuclear or renewables to generate most of our electricity, and realistically, only nuclear has a chance of that in the next 20+ years.

    (DIsclaimer: All numbers are ballpark what I remember off the top of my head. They may not be exact.)