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Microcap & Penny Stocks : BAAT - world records for electric vehicles with zinc-air -- Ignore unavailable to you. Want to Upgrade?

To: dwight martin who wrote (1910)	2/17/1998 11:41:00 AM
From: shashyazhi	Read Replies (1) \| Respond to of 6464

My main objection to hybrid diesel electric cars has always been the simple formula involved in efficiency of energy conversion. Let us say that, at best, the chemical to mechanical energy conversion of the internal combustion engine is 25%. And some 15% is lost in the gear train. You are down to 21.25% efficiency with the standard transmission arrangement. But what if you use your 25% efficient IC engine to drive a 50% efficient DC generator which, in turn sends electricity to a 50% efficient DC motor to drive the wheels? Do the math, and you will see that the efficiency is down to 6.25%, disregarding the probability that you have a battery in the system storing some of that power and returning it at 50%. If you know what the efficiency factors of AC energy conversion you can factor them into the equation. I don't happen to remember what the efficiency of 3 phase alternators is, but it is higher than 50%. If it was 75% you would still only come out with 14% efficiency using the IC engine to drive an AC generator to drive an AC motor. I have been reading books like "Engineer's Dreams" and magazines like Popular Science and Popular Mechanics since I was a little kid, but none of the dreamers has come up with any solution as elegant and efficient as the IC engine with a mechanical transmission. Steam? Try to fire up a boiler and build pressure before work every morning. Gas turbines? They cannot be produced cost effectively and still have a high enough compression ratio to realize their efficiency potential. Wankels? Hmmm. There's an eccentric shaft in there that suspiciously resembles, dare I say it? A crankshaft! Storing energy in a capacitor? Too dangerous to the backyard mechanic. Storing energy in a flywheel? How do you retrieve it efficiently? Do you use a friction clutch, or does it drive a 75% efficient AC generator driving a 75% efficient AC motor. Or is the flywheel actually the rotor in some sort of AC motor? Maybe there is only one stage of intermediate energy conversion? 25% IC efficiency time 75% still equals only 18.75% efficiency. You just cannot beat the efficiency of that car you drive today. But you can hope to get a little better fuel economy, which is not the same thing as efficiency. The mechanical transmission is the key to the best efficiency by keeping the engine rpm in the most economical range.