tag:blogger.com,1999:blog-19508699.post5982348526973805878..comments2024-03-29T06:38:18.116+00:00Comments on Energy Balance: Water-Demand makes Renewables Unsustainable.Professor Chris Rhodeshttp://www.blogger.com/profile/12060542089215379056noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-19508699.post-89990662222562755032017-08-29T07:34:31.727+01:002017-08-29T07:34:31.727+01:00Great pleasure reading your post.Its full of infor...Great pleasure reading your post.Its full of information, thanks for sharing.<br />Cost For Home Solar Panelshttp://www.poulinsolarpro.com/noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-34266682283361955552009-10-05T07:55:18.053+01:002009-10-05T07:55:18.053+01:00Hi Jane,
that's very interesting and worth lo...Hi Jane,<br /><br />that's very interesting and worth looking into further, which I shall do.<br /><br />I think it is a case of "horses for courses" with all kinds of solar and other energy technology. So, as you say, CPV may prove best for arid climates but CSP for sunnier climes where there is water in reasonable access since the overall efficiency runs around the typical Carnot cycle value of about 35%.<br /><br />Best wishes,<br /><br />Chris.Professor Chris Rhodeshttps://www.blogger.com/profile/12060542089215379056noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-85420985884795989722009-09-30T19:30:08.739+01:002009-09-30T19:30:08.739+01:00Hi,
On the topic of CPV, this technology now has ...Hi,<br /><br />On the topic of CPV, this technology now has efficiencies that typically beat 25%, and with higher manufacturing volumes have reached a levelized cost of electricity that in many cases is competitive with or better than concentrated solar thermal.<br />Coupled with very low water requirements and low land impact this makes this technology a very promising approach for high solar resource locations in general, and hot dry locations in particular, without having some of the drawbacks you mention for CSP.<br />Worth checking out...<br /><br />JaneJanehttps://www.blogger.com/profile/12407972322817710162noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-47232605462749093532009-09-29T07:44:54.890+01:002009-09-29T07:44:54.890+01:00Hi Peter,
thanks for this information. So this is...Hi Peter,<br /><br />thanks for this information. So this is concentrating PV rather than concentrating solar thermal which does seem to use cooling water. I know the latter are supposed to be more efficient in terms of energy recovery in the form of electricity, but there is the water issue.<br /><br />Best regards,<br /><br />Chris.Professor Chris Rhodeshttps://www.blogger.com/profile/12060542089215379056noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-4051685148356438942009-09-28T21:11:22.205+01:002009-09-28T21:11:22.205+01:00Hi Chris,
There is a company in California calle...Hi Chris, <br /> There is a company in California called “Sol-Focus” which produces concentrating solar pv systems. These do not use any water for cooling purposes. Their products consist of arrays of parabolic mirrors, which focus the sun’s rays directly onto the pv unit. I understand that they have a plant somewhere in Spain.Unknownhttps://www.blogger.com/profile/12842364105214541179noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-27339580624478244732009-09-28T13:52:05.694+01:002009-09-28T13:52:05.694+01:00Yes, I remember Mark Twain's remark! Perhaps i...Yes, I remember Mark Twain's remark! Perhaps it will prove apposite?<br /><br />Water does seem to be the unthought of or unmentionable resource for so many aspects of energy...<br /><br />Regards,<br /><br />Chris.Professor Chris Rhodeshttps://www.blogger.com/profile/12060542089215379056noreply@blogger.comtag:blogger.com,1999:blog-19508699.post-71069615431086133572009-09-27T23:21:59.837+01:002009-09-27T23:21:59.837+01:00It is funny that you mention the amount of water n...It is funny that you mention the amount of water necessary to grow enough plant matter to produce ethanol in California because we are experiencing a third year of drought with no end in sight. Plus there is the added problem that the pumps feeding water from the Sacramento River to the farms San Joaquin had to be heavily curtailed because enough water has to be left to keep an endangered fish, the delta smelt, from being decimated. Combine this with the fact that the Sacramento River feeds into environmentally sensitive areas of the San Francisco Bay where salt water intrusion is becoming a problem. Then there is the problem about allocations from the Colorado River which will soon be reduced so the water can go to Arizona and Mexico.<br /><br />Things are getting so bad that some water districts like those in Long Beach, Marin County and San Diego County are actively pursuing desalination projects. I have heard positive and negative things about desalination but good or bad that appears the direction we are heading.<br /><br />I guess the famous American writer Mark Twain was correct when he said "whiskey is for drinking and water is for fighting" because I predict there will be a lot more legal fighting over this precious resource in the future.Marknoreply@blogger.com