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Old 07-02-2013, 12:25 PM   #30 (permalink)
ConnClark
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Quote:
Originally Posted by sheepdog 44 View Post
A Leaf uses a 24 kwh pack for about 71miles of range. Thats 24kwh + 31kwh = 59 kw hours of total energy usage. Thats a 90% increase, with driving 71 miles a day which is a ridiculous commute over 2 hours.

A compact gas car with reasonable efficiency gets 35mpg average. A gallon of gas contains 36.6kwh, and the car would use 2 gallons for the 71 miles. Thats a gas use of 73.1 kw + 31 kwh of the house = 104.1 kw hours of energy use, a 335% increase from the energy used to power your home, and a 76% increase in energy use from the combined energy of driving an electric car and powering a house!

Gas and Coal are both finite fossil fuel power sources. Where will the efficiency come from? from not burning twice as much energy in gasoline as can be obtained from the electrical grid. From using half as much fossil fuels from a coal plant, polluting half as much as a gas car.

There are valid arguments against Electric Vehicles that i agree with, even being an advocate for EV's. Price, battery pack lifespan, better use of pure EV batteries in many hybrids with small packs to displace the most gasoline used.
You're making the assumption that energy conversion is 100% efficient for electrical production. In reality its only about 33% on average. If you want to take from that the Grid losses of about 5% and consider batteries are only 85 to 90% efficient with charging and about 90 to 95% efficient discharging. All said and done it puts you right back at the same efficiency of a standard car (Note there are other losses that could be considered too).
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