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Old 05-13-2012, 03:29 PM   #38 (permalink)
IamIan
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Quote:
Originally Posted by mechman600 View Post
making hydrogen to power a car produces six times the CO2 than if you powered the same car with gasoline in the first place.

The long tailpipe emissions of a hydrogen car are six times that of a gasoline car.

Electric is better in every respect.
Some of that ratio might be changing eventually ... to narrow that 6:1 gap down ... even if not enough to change the results.

They are making algae which produce H2 as a byproduct of photosynthesis instead of the natural plant hydrocarbon sugars... currently not any where near cost effective ... but it will be closer than the current gap... even if it still will not close the gap.

Although other technologies can convert solar energy to electricity more energy efficiently than photosynthesis ... the modified algae based version is a self replicating system ... solar cells and the like might be more efficient energy conversion ... but they don't self replicate more of themselves... so the modified algae has a potential production benefit.

Once the conversion has been made they each have their own additional sources of loss:

BEV:
electricity has the grid losses ... charger losses ... battery cycle losses ... motor controller losses ... motor losses.

Hydrogen:
Has more distribution losses ... to compress it , transport it, refrigerate it, etc ... has far more losses in the ICE ... than a electric motor ... and if you use a fuel cell you have all the losses of a BEV expect you trade a battery for the fuel cell ... and I don't know of any ( even prototype ) fuel cells that can get to the cycle efficiency of modern Batteries.

So in Short:
Due to the additional losses in distribution, compression, refrigeration, and conversion to mechanical energy ... Hydrogen wold have to be produced from the initial energy source more energy efficiently than one could produce electricity from that same source ... That's a really really tall order ... none of the current systems I know of are that energy efficient at producing hydrogen ... and even if some of the new ones reach a even point at production ... Hydrogen still have other losses down stream ... in order for it to be equal at the end use , it needs to have a significant production efficiency benefit ... which it doesn't have ... and doesn't look like it is ever going to.

- - - - -

As for the Volt ... if 8 Million lines run everything for the 787 Dreamliner as the article claims ... 10 million ( ~25% more ) does seem kind of out of scale for the Volt ... Think about that scale for a minute ... the Dreamliner has a larger electrical system ... more feedback and sensors from the jet engines than the Volt gets from the ICE ... additional aeronautical instrumentation ... more communication system not only the the plane but the wifi / phone service / entertainment / etc ... for all the ~290 passengers... yeah ... Me thinks they could improve the efficiency of that code considerably.

Although as others have already posted ... they might not care to spend the cost of labor to do so when the cost of the computer chip is so low.

Last edited by IamIan; 05-13-2012 at 03:37 PM..
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