Monday, March 10, 2008

Solar-powered car!

This guy is a perfect example of the kind of pseudo-intellectual activist we are overrun with nowadays. Oh, I don't have a problem with his experiment, in fact it looks like something I would do. However, his comments about how the stupid California legislature backed away from a wonderful bill that would have mandated zero-emissions vehicles, and about how a good government would supply solar charging stations in parking lots everywhere, prompted me to post a few comments.
First, government-supplied solar charging stations. Most leftist-activists have no problem with money being extorted from everyone at the point of a gun, to support projects they believe in. Of course, they don't like to have it described in those terms; they prefer to just say it's our "duty".
Second, just because he lives close enough to work to make an EV a workable solution, doesn't make that true for everyone.
Third, there is no such thing as a zero-emission vehicle. If you don't believe this, research what goes into the production of a battery, and what goes into recycling one. Also research how long that battery lasts before it has to be replaced.
OK, I won't belabor those points. Most of you probably already know it anyway. Let's cut to the chase: demonstrating that this guy is full of crap. It's simple, when you crunch the numbers. Think of the smallest, most economical car you have ever seen. I'm talking about cars that are legal to drive on public roadways. How much horsepower does its engine produce? How about a Ford Festiva (42 mpg highway)? 65 horsepower. Or how about the Renault 5 (known in the US as the LeCar), of which this particular EV is a conversion? It was available with several different engines, the smallest of which was 36 horsepower. How about the record-breaking Loremo that is supposed to go on sale in the European market next year? That one is a good choice: it claims 157 mpg from a 20 horsepower diesel engine. Let's use that as a baseline. Now let's give Uncle Bob as he calls himself, the benefit of the doubt and say he can manage with only half that, or 10 horsepower. Let's also give him the further benefit of allowing him 100% efficiency in his setup, even though we know that battery charging is only 66% efficient, max; and that his inverter is about 90% efficient, and there are more inefficiencies that, together, would bring his total efficiency to less than 50%. We'll ignore that. We'll also ignore the fact that Uncle Bob lied right off the bat when he said that his PV panels were putting out 200 watts, when we all know that 6.82 amperes plus 6.86 amperes times 12.52 volts equals 171.2736 watts. We'll let him claim 200 watts, as well as 100% efficiency. OK, based on that, let's calculate how much power Uncle Bob produced with his setup. We'll assume he left it setup from sunup to sundown, since we're already being so generous; why stop now?
The insolation index as it relates to PV panels is an estimate of the average number of hours per day one can expect full rated output from a panel. Even if the sun is up for 12-14 hours, you cannot expect a panel to produce full rated output for all those hours. Areas that receive lots of sun, like southern California, are rated at about 5-6 hours of full output. This means that, if the panel is exposed to the sun from sunup to sundown, it will produce a total amount of energy equal to outputting its rated power for 5-6 hours. Again, we'll give Bob the benefit of the doubt and allow him 6 hours.

OK, crunch time: given the rose-colored-sunglasses view we have specified, 200 watts times 6 hours equals 1200 total watt-hours. One horsepower is approximately 746 watts. That means Bob theoretically stored up 1.61 (rounding up) horsepower/hours of energy. We already determined that he would need 10 horsepower to drive his car, so 1.61 divided by 10 equals .161 hour, or just under 10 minutes drive time. Again, we'll be generous and allow Bob 10 minutes; BUT we're not gonna allow him to recharge overnight on grid power (that would be blatant cheating), so he has to drive both ways on that solar charge.
Hope Bob lives within 5 minutes of work, because that's all the charge he's getting. If so, I recommend that he save a lot of trouble, and just walk.

Speaking of which, even walking isn't zero emissions. When you walk, you increase your respiration, meaning you are increasing your production of...
CO2, carbon dioxide which is what we all breathe out. Quick, what's the most commonly referenced "greenhouse gas" that's supposedly causing global warming?

PS: Why am I picking on Bob? Actually, it's because he showed us some real numbers; he was one of the more believable green activists on Youtube. Youtube is absolutely full of videos about free energy (I don't classify PV with that group, btw: I know PV works; in fact I have some panels myself), and most of them show a tiny load like a light bulb being driven by a contraption that is, itself, being powered by a car battery or some such. Of course, they never show you how much power is being withdrawn from that car battery to drive the contraption and power the light bulb.
Those crackpots aren't even worth taking the time to debunk. When they show me a single car battery driving a contraption which is powering an air conditioner for a few hours, I'll take notice.

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