Solar cell
in [Design]
|
From: Winston on 18 Apr 2010 02:27 On 4/17/2010 1:02 PM, Phil Hobbs wrote: (...) > Of course, Shoreham and Indian Point looked economic when they were > built, too. ;) At least there won't be any big decommissioning costs > with solar. But just think of the onsite storage costs for spent photons! --Winston
From: Paul Keinanen on 18 Apr 2010 02:56 On Sat, 17 Apr 2010 21:14:57 +0100, Dirk Bruere at NeoPax <dirk.bruere(a)gmail.com> wrote: >On 17/04/2010 20:39, Jan Panteltje wrote: >> On a sunny day (Sat, 17 Apr 2010 11:25:32 -0600) it happened hamilton >> <hamilton(a)nothere.com> wrote in<hqcqu9$7ve$1(a)news.eternal-september.org>: >> >>> On 4/17/2010 10:41 AM, Jan Panteltje wrote: >>>> On a sunny day (Sat, 17 Apr 2010 08:57:14 -0700) it happened Don Lancaster >>>> <don(a)tinaja.com> wrote in<82u42oFov7U2(a)mid.individual.net>: >>>>> There is NO best solution. >>>>> >>>>> All of photovoltaics is an outright scam to steal state and federal funds. >>>>> >>>>> Not one net watthour of pv energy has EVER been produced! >>>> >>>> Bad day? >>> Ok, the link now works. >>> >>> Dons argument is what the non-green types have been saying for years. >>> >>> It costs too much to develop and manufacture green technologies then to >>> stick to the 'tried-n-true' fossil fuels. >>> >>> He does have a point, the cost to early adapters will never be paid back. >>> >>> But, I think we need to start somewhere, and PV solar needs to have >>> money to continue to develop and innovate. >>> >>> As time passes and science has the money to continue, they will get >>> there. ( maybe not in my lifetime, but they will get there ) >>> >>> >>> hamilton >> >> Yes, there are for example investors in Europe planning a solar plant in the Sahara desert IIRC. >> Billions have been raised, DC very high voltage lines to carry it all over Europe. >> With all that unrest I think the biggest obstacle is a political one. >> US has Mojave desert, would be a nice place for solar .. >> but the same greens that want solar also want to protect the bugs and snakes that live there ;-) >> Just wait until get get cold feet, they will change their mind. >> OTOH nuclear seems to be the only real option right now. >> And if 'electric cars' were to really happen, then all bets are off, >> new grid, new power plants... >> Dunno. > >That's why Spain is the ideal location. The Desertec plan and the existing stations in Spain and US are based on concentrated solar thermal power, not PV cells, apparently for economical reasons. In solar thermal plants, the sun heats a fluid which then drives a conventional gas or steam turbine. It would make even more economical sense, if the excess heat available on the "cold" end of the turbine could be used for something useful, such as running absorbtion chillers or desalination plants. PV panels on individual houses will make economical sense only in hot countries if the cost of energy changes on an hour or shorter bases. During hot sunny afternoons, the electric consumption will reach the annual peak due to air conditioning. Much of the power during those hours needs to be produced with simple cheap gas turbines (used only a limited number of hours each year), but the overall efficiency is low and they need to use more expensive fuels such as natural gas or oil. If this extra cost during summer day hours is charged from the consumers, it would make sense for the consumer to use individual PV panels for running the air conditioning, thus avoiding buying expensive peak electricity from the power company. In such cases there would be less need to have an expensive inverter to feed power back to the grid. Of course, simple thermal collectors could be used to drive an absorbtion cooler, even if the cooler efficiency is lower than a compressor cooler, this avoids the low efficiency light to electricity conversion in PV cells.
From: Paul Keinanen on 18 Apr 2010 04:12 On Sat, 17 Apr 2010 23:10:21 -0500, "krw(a)att.bizzzzzzzzzzzz" <krw(a)att.bizzzzzzzzzzzz> wrote: >On Sun, 18 Apr 2010 04:57:40 +0100, Dirk Bruere at NeoPax ><dirk.bruere(a)gmail.com> wrote: > >>On 18/04/2010 04:38, dagmargoodboat(a)yahoo.com wrote: >>> Are you sure about that Jim? Just about all these solar projects are >>> about the subsidies, and little else. >>> >>> If solar were economic, 'greedy' capitalists would capitalize on it in >>> droves, benefiting everyone. That's the beauty of free markets. >> >>So the fact that installed capacity is doubling every 2 years and just >>about everyone is scrambling to produce them is evidence that only govts >>are buying them? 8 more doublings will equal the entire installed >>generating capacity from every other source. > >CAPACITY might be doubling every two years, but that just reflects the state >of the art of government subsidies, not solar power. Eight more doublings >will likely bankrupt every country on the planet. Direct government subsidies (paid by taxes) or feed in tariffs (paid by users of electricity produced in a different way) are possible only for means of production with a low market share. A government would be stupid, if it guaranties that it is going to pay say 10x the market price for any _new_ installations started between today and 2050. It is a different thing than guarantees that a certain price will be paid for the next ten years for systems started this year. Each year, the market share should be evaluated, if new applicants are accepted into the program. This market share criterion should be stated when such programs are started.
From: Robert Baer on 18 Apr 2010 04:43 eryer wrote: > Hi, > I want to realize (for hobby) a battery charger using solar cell. I've > found this sensor > http://www.clare.com/Products/SolarCell.htm > Its output voltage is high and can be used without step-up transformer > (like any typical solar cell). So, i can use > * a typical solar cell (with millivolt output voltage) and a step-up > transformer > * this sensor > For you, what is the best (performance) solution? Well, for starters, solar cells can output around 1.3V with a reasonable load - a lot more that "millivolt output". Secondly, the current capability of those Clare "cells" is a bit miserly. To be fair tho, that is expected with such dinky arrays.
From: Robert Baer on 18 Apr 2010 04:45
Jan Panteltje wrote: > On a sunny day (Sat, 17 Apr 2010 08:57:14 -0700) it happened Don Lancaster > <don(a)tinaja.com> wrote in <82u42oFov7U2(a)mid.individual.net>: > >> On 4/17/2010 1:34 AM, eryer wrote: >>> Hi, >>> I want to realize (for hobby) a battery charger using solar cell. I've >>> found this sensor >>> http://www.clare.com/Products/SolarCell.htm >>> Its output voltage is high and can be used without step-up transformer >>> (like any typical solar cell). So, i can use >>> * a typical solar cell (with millivolt output voltage) and a step-up >>> transformer >>> * this sensor >>> For you, what is the best (performance) solution? >> >> There is NO best solution. >> >> All of photovoltaics is an outright scam to steal state and federal funds. >> >> Not one net watthour of pv energy has EVER been produced! > > Bad day? It is those clouds that made the JFET "photocells" work like JFETS.. |