tag:blogger.com,1999:blog-29868932.post5781904216629944018..comments2024-02-14T22:50:48.749+10:30Comments on Bill Kerr: david mackay: do the arithmeticBill Kerrhttp://www.blogger.com/profile/00206808014093631762noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-29868932.post-58603735599707370032010-02-10T21:55:16.870+10:302010-02-10T21:55:16.870+10:30I agree with you about the arithmetic. I've he...I agree with you about the arithmetic. I've heard engineers involved with alternative energy make claims that someday in the near future alternative energy will be our main source of power, and energy from fossil fuels will be in the minority. With the power output of alternative energy sources now, looked at on a per unit basis, it seems to me that such projections are wildly unrealistic. I don't see how a competent engineer could say these things and be honest. I'd much prefer it if more money was put into R&D for making alternative energy more efficient, rather than using it for build out.<br /><br />I was talking a couple months ago with an engineer who works for an energy company. He said that from an environmental standpoint he liked wind, but it's inconsistent and it doesn't scale well.<br /><br />He liked solar for specific sites, because it scales well to individual buildings, but it was only economical in certain circumstances, because you either have to choose between powering your building with solar during the day, and using the grid 100% at night, or storing power in batteries so you can continue using solar-generated power at night. The latter is hugely expensive right now, and compared to the price of getting power from the grid it doesn't make sense.<br /><br />One common circumstance where he thought solar would make sense was with office buildings, especially if workers converted to electric vehicles. He thought of a design for a parking garage where everyone could plug in and recharge their vehicles while they were working during the day. As far as people's homes, he didn't see it being that practical. Most people are away from their homes during the day anyway. I have heard of people selling their surplus solar power back to the grid, but I don't know how that works out economically.<br /><br />He said that using solar power plants was not all that realistic, because of all the land that's required for it, and it's inconsistent.<br /><br />I have heard a few proposals for wind and solar power storage on a large scale using pumps to pump water up into a storage basin in mountainous or hilly areas, and then using that as a source of potential energy when the wind isn't blowing enough, or during the nighttime in the case of solar, but this is more wishful thinking. With wind and solar's inefficiency you have to try to preserve every bit of energy you can get from them. Just transmitting the power over large distances dissipates the energy in power lines before anyone can use it. With storage, energy would be lost in the process of storing the water, and then generating power from it. A large reserve of water would need to be used, much more than would be needed for energy storage, because the contingency of drought would need to be taken into consideration.<br /><br />As far as power plant solutions, there were two that we both liked: natural gas, because it pollutes less and scales similar to coal, and nuclear. The engineer much preferred nuclear, because of the safety improvements that have been made in plant designs, and the fact that a little fuel lasts a long time. It also requires less manpower to run a plant (though the security requirements are greater). From what I remember he said there was technology for reprocessing spent fuel and reusing it for power generation as well.Mark Millerhttp://tekkie.wordpress.comnoreply@blogger.com