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Originally Posted by jesterbot
I would definitely not say I'm anti-green, I'm simply anti-green-for-the-wrong-reasons. I would love it if we could flip a switch and the world could suddenly run on renewable, clean energy (with no negative side effects).
Unfortunately, that's not the case and people tend to focus exclusively on the downstream (a car that produces zero emissions, or a solar panel that produces renewable power) and ignore the upstream (pollution/waste in the process of building the panel/car, the energy consumed to create it versus the lifetime energy saved/produced by the product itself, etc).
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it seems that cars that are focused on green tech: Ford escape hybrid for example uses a lot more recycled materials then traditional cars. As far as batteries and solar panels making more waste then internal combustion cars, its hard to compare but as total mass waste generated, I doubt it. If you weigh the total mass of the petroleum saved by using say, a hybrid compared to the waste produced by the batteries its no contest. As far as I know, Lithium Ion or NiMH batteries aren't as toxic as the old school batteries. Silicon based solar panels manufacturing do use some nasty chemicals, but the silicon chip industry do a pretty good job at recycling/neutralizing the waste. Polymer based solar panels and wind generation makes that argument even more complicated. As far as batteries, is it worse then the chemicals used to refine petroleum? what about all the motor oils used throughout the life of the vehicle? catalytic converters and oil filters? I'm not sure...
Quote:
Originally Posted by Icedog_16
IMO, where this idea falls flat is that energy is lost in each step of the chain; the more steps, the more is lost. Internal combustion is more efficient in this respect, which is why it's so difficult to displace gasoline when it comes to meeting transportation energy needs (gasoline very portable and energy-dense to boot, which gives it the edge in practicality and convenience). With electric, you have to deal with the inefficiency at the plant (heat losses, frictional losses, etc), power loss during transmission, loss at the transformer at your house, loss when charging the battery, loss when discharging the battery, frictional losses (IC has that as well); all of those add up when talking about 'well-to-wheel' efficiency.
This might give you a better idea of what I'm talking about : The Secret Lives of Energy - The Energy Problem - Conservation of Energy |
Quote:
Originally Posted by Icedog_16
Ten times more efficient seems highly unlikely. The electric vehicle is more efficient tank-to-wheel than internal combustion, but even that's not ten times more efficient.
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not 10 times, but 2x...
Internal combustion engines in cars are very inefficent because they have to work though a big RPM range. Power Plants that burn hydrocarbons runs at the RPM of Peak efficiency: Electric motors are also more efficient though out a big range of RPMs. Also, the power plant & transmission line argument goes away when people convert to point of us Solar/wind power generation.
Processing EVs & Power Plants: 39% (Electricity Generation) | ICE & Fuel Refining92% (Fuel Refining)
Transmission Lines: EVs & Power Plants 95% | ICE & Fuel Refining-N/A
Charging EVs & Power Plants 88%| ICE & Fuel Refining-N/A
Vehicle Efficiency: EVs & Power Plants 88% | ICE & Fuel Refining 15%
Overall Efficiency: EVs & Power Plants 28% | ICE & Fuel Refining 14%
this is only comparing EVs to ICEs, because the calculation for a hybrid/plug-in hybrid is much more complicated.