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On Wed, 21 Nov 2007 17:39:17 GMT, Larry Dighera
wrote: On Tue, 20 Nov 2007 20:50:55 -0500, "Roger (K8RI)" wrote in : As has been publicized, we don't have the grid capacity to support much in the way of all electric cars. The same is true for Hydrogen. It's either produced from fossil fuels with a lot of polluting byproducts or takes a whale of a lot of electrical energy to produce from water. When/if worldwide photovoltaic production ever meets consumer demand, you are going to see an enormous increase in solar power installations, not only in commercial buildings, but residences as well. Today, the excess electricity generated by a home's photovoltaic power generating system is used to turn the electric utility meter backwards. As electrically powered vehicles become more mainstream, that excess solar power could be used to directly charge vehicle batteries or for hydro-electrolysis to generate hydrogen gas for fuel. This doesn't change the lack of grid capacity. Ask the State of Wisconsin which has a large wind farm. The state agreed to purchase any electricity the grid couldn't handle. It's costing them many millions of dollars. We don't have the economically viable technology for all electric vehicles to have enough range. Generating H2 with the excess energy sounds good, but how do you generate and store enough if you don't live in the SW? Side benefits of residential solar power generation are the peace of mind inherent in the redundancy of distributed (as opposed to central) power generation and the resulting robustness against massive power outages due to a cascade of equipment outages triggered by a single-source failure, the ability to "thumb the eye" of oil robber-barons, the reduction in the production of pollutants, insurance against the inevitable increases in the price of energy, and virtue of abandoning 19th century technology for a more enlightened solution. It comes down to economics and geographic location. My daughter's husband is a consultant in the business. We sat down and figured a hybrid system of both active and passive solar would cost me close to $50,000 up here and unlike California we receive no subsidies for either active or passive solar panels. Price photovoltaic panels per KWH. The price without a subside is enough to scare most any one off. Alcohol is an interim solution with the hybrid being by far the most economical and quickest to implement of the interim solutions. As for grid capacity we are rapidly coming to the point of real time usage monitoring with remote setback of heating and air conditioning. Here with peak rates of about 10 cents per KWH we wouldn't see the savings of those fortunate souls paying 38 cents during peak demand out in the Republik of Kalafornia. OTOH solar panels don't do us much good either. Why? Photovoltaic panels are able to convert infrared isolation even on cloudy days. But that ain't much power out. it's only a small fraction of what you get in direct sunlight and solar panels are not all that efficient at best. Also we're 43'37" N and the days are several hours shorter up here than in say Georgia or even California. Also you can see the power drop due to clouds, or just due to dust and dirt collecting if you don't clean them every couple of weeks. They also age so it's not a one time cost. Efficiency is going up, but electricity from solar panels is still about 3 to 5 times the cost of that from the power grid in areas where sunlight is plentiful and the atmosphere is seldom cloudy. Here with 10 cents per KWH and we have about 3 days a month without some clouds it's probably more like 5 to 7 times. And even when they do get the cost down and I expect they will, the power grid is still limited as to the amount they can buy back (or handle) When that point is reached the payback for power into the grid will drop and at times they may not even accept power. As I mentioned the wind farm in Wisconsin and their problems. There is a Silicon plant near here that is multiplying their capacity several times over and they just finished doubling the size of the plant. The amount of pure Silicon coming out of there is staggering. Wafer size has gone from 1/2 to 3/4 of an inch when I started in the industry to a current of 14 inches or there abouts. Still the waste of making wafers from silicon rods is over 50%. Considering it used to be on the order of 80 to 90% that's pretty good. Many years ago when loss was much greater they developed some new sawing techniques that cut the waste in half. it was still tremendous, but the increase in yield almost caused several of the suppliers to go out of business. One did. We still have a long way to go before solar cells become economically viable except in some select areas. Roger (K8RI) |
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On Thu, 22 Nov 2007 04:45:24 -0500, "Roger (K8RI)"
wrote in : On Wed, 21 Nov 2007 17:39:17 GMT, Larry Dighera wrote: On Tue, 20 Nov 2007 20:50:55 -0500, "Roger (K8RI)" wrote in : As has been publicized, we don't have the grid capacity to support much in the way of all electric cars. The same is true for Hydrogen. It's either produced from fossil fuels with a lot of polluting byproducts or takes a whale of a lot of electrical energy to produce from water. When/if worldwide photovoltaic production ever meets consumer demand, you are going to see an enormous increase in solar power installations, not only in commercial buildings, but residences as well. Today, the excess electricity generated by a home's photovoltaic power generating system is used to turn the electric utility meter backwards. As electrically powered vehicles become more mainstream, that excess solar power could be used to directly charge vehicle batteries or for hydro-electrolysis to generate hydrogen gas for fuel. This doesn't change the lack of grid capacity. If the home's photovoltaic power generating system is used to turn the electric utility meter backwards, it doesn't require any additional grid capacity. We don't have the economically viable technology for all electric vehicles to have enough range. Generating H2 with the excess energy sounds good, but how do you generate and store enough if you don't live in the SW? Here's how it's being done in New York: http://www.distributed-energy.com/da...gy-20329-1.pdf The Solar-Hydrogen Home The US Merchant Marine Academy and the New York Institute of Technology joined forces to build a home for the 2005 Department of Energy Solar Decathlon Competition. The home, which incorporated a Distributed Energy Systems’ HOGEN RE hydrogen generator, was in a class of its own. In a typical “off-grid” scenario, a large battery bank is required to store energy. In the “solar-hydrogen” home, solar energy is stored in the form of hydrogen gas generated from the HOGEN RE hydrogen generator. When it is dark, instead of drawing energy from a battery bank, hydrogen gas is converted into electricity through a fuel cell. During the day when there is plenty of energy from the sun, water is converted into hydrogen gas through the use of a HOGEN RE hydrogen generator. Side benefits of residential solar power generation are the peace of mind inherent in the redundancy of distributed (as opposed to central) power generation and the resulting robustness against massive power outages due to a cascade of equipment outages triggered by a single-source failure, the ability to "thumb the eye" of oil robber-barons, the reduction in the production of pollutants, insurance against the inevitable increases in the price of energy, and virtue of abandoning 19th century technology for a more enlightened solution. It comes down to economics and geographic location. My daughter's husband is a consultant in the business. We sat down and figured a hybrid system of both active and passive solar would cost me close to $50,000 up here and unlike California we receive no subsidies for either active or passive solar panels. Price photovoltaic panels per KWH. The price without a subside is enough to scare most any one off. That's because the demand for photovoltaic panels exceeds the worldwide manufacturing capacity. As more manufacturing facilities come on-line, I would expect to see prices decline due to competition. Alcohol is an interim solution with the hybrid being by far the most economical and quickest to implement of the interim solutions. As for grid capacity we are rapidly coming to the point of real time usage monitoring with remote setback of heating and air conditioning. Here with peak rates of about 10 cents per KWH we wouldn't see the savings of those fortunate souls paying 38 cents during peak demand out in the Republik of Kalafornia. OTOH solar panels don't do us much good either. Why? Photovoltaic panels are able to convert infrared isolation even on cloudy days. But that ain't much power out. it's only a small fraction of what you get in direct sunlight and solar panels are not all that efficient at best. You can purchase ~40% efficient solar cells today. The technology is improving. Also we're 43'37" N and the days are several hours shorter up here than in say Georgia or even California. Also you can see the power drop due to clouds, or just due to dust and dirt collecting if you don't clean them every couple of weeks. They also age so it's not a one time cost. Efficiency is going up, but electricity from solar panels is still about 3 to 5 times the cost of that from the power grid in areas where sunlight is plentiful and the atmosphere is seldom cloudy. Here with 10 cents per KWH and we have about 3 days a month without some clouds it's probably more like 5 to 7 times. In that case, you'd have to increase the solar generating area to compensate for the reduction in isolation. And even when they do get the cost down and I expect they will, the power grid is still limited as to the amount they can buy back (or handle) When that point is reached the payback for power into the grid will drop and at times they may not even accept power. As I mentioned the wind farm in Wisconsin and their problems. I believe it's a matter of the utility reducing their output during periods of excess locally (solar) generated power. There is a Silicon plant near here that is multiplying their capacity several times over and they just finished doubling the size of the plant. The amount of pure Silicon coming out of there is staggering. Wafer size has gone from 1/2 to 3/4 of an inch when I started in the industry to a current of 14 inches or there abouts. Still the waste of making wafers from silicon rods is over 50%. Considering it used to be on the order of 80 to 90% that's pretty good. Many years ago when loss was much greater they developed some new sawing techniques that cut the waste in half. it was still tremendous, but the increase in yield almost caused several of the suppliers to go out of business. One did. We still have a long way to go before solar cells become economically viable except in some select areas. Roger (K8RI) Perhaps, but there seems to be a definite increase in their use out here. |
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As with any energy conversion scheme, a viable storage medium is the
key. Perhaps the hydrogen generator is what is needed. As for the source of this energy, how about photovoltaic roof shingles? Look at this: http://www.technologyreview.com/Energy/17129/ David Johnson |
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