The European Tribune is a forum for thoughtful dialogue of European and international issues. You are invited to post comments and your own articles.
Please REGISTER to post.
paul Paul Gipe
If I got the categories right, CSP includes the more mature solar-thermal power technologies, in which a heat-absorbing medium drives a generator; as well as concentrated photovoltaic (CPV), in which the concentrated sunlight is absorbed by a high-quality multijunction solar cell.
Is this really how CPV is categorised by the industry? It certainly doesn't make any sense in terms of your discussion to group CPV with solar-thermal:
I looked up a few sites and wasn't sure myself (as indicated at the start).
little economy of scale.
Is that true? For all types of CPV? Does the requirement of tracking systems not result in economies of scale? For that matter, how big can a single concentrated solar unit (concentrator + single receiver solar cell) be? (I'm really asking, I don't know much of CPV.) *Lunatic*, n. One whose delusions are out of fashion.
The ambiguity if that CPV needs to be cooled, and if you use the heat contained in that coolant to some useful purpose, then you have a hybrid CPV/CSP system, even if the CSP element is essentially co-generation.
The built in advantage that PV has in generating electricity is that it generates electricity originally, rather than collecting heat and converting it. The flipside for an application actually required heat of a grade that CSP could deliver would suggest an application for CSP to provide that heat, either directly or upgraded by using it as the above ambient temperature source for a heat pump.
Which clips around the vision of a decade ago of utility scale CSP installations and dispersed PV installations, to utility scale CPV installations and a mix of dispersed CSP and PV installations.
On the residential side of the grid, where a fair incentive would include the reduction in load at the substation serving that residential neighborhood, a mixed CPV/TSP panel that harvests both heat and electric power would seem to offer some potential utility. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
In real terms I think PV and concentrated solar-thermal are the two big ones, which makes the exact drawing of the lines less relevant as long as these are two are in seperate cathegories.
And just to mix things up, there also exists combined PV and thermal like Zenith Solar. Sweden's finest (and perhaps only) collaborative, leftist e-newspaper Synapze.se
As may have been mentioned here in the past, there is concern about whether Arizona may effectively ship a meaningful fraction of its precious water rights to California in the form of electricity by this method.
http://www.azcentral.com/arizonarepublic/news/articles/2010/01/17/20100117water-solar0117.html
I think it's pretty clear that PV and batteries are going to be the way to go ultimately. Timeline is uncertain...
Yeah, I know you're talking about electricity. Align culture with our nature. Ot else!
The parts of the US which are especially suited for CSP (both thermal and PV) happen to have a peak period which is largely driven by air conditioning, if I have understood directly. This means that PV can actually get the best tariffs, and that the storage possibilities of thermal CSP are negated.
This is a severe handicap for thermal CSP, because the southwest USA is where it's at currently for utility-scale solar.
PV CSP is starting to take off in a big way there, for that reason. SDG&E, Soitec Add 2 Local Solar Sites | Xconomy
San Diego Gas & Electric has added two more 25-year contracts with French-based Soitec, which will supply a total of 125 megawatts from solar energy sites using Soitec's Concentrix CPV (Concentrating Photo-Voltaic solar panel modules. In a statement today, the two companies say Soitec Solar Development will manufacture the modules in a new factory to be built in San Diego. The two local agreements follow three previous contracts for 30 megawatts of CPV-generated solar power.
San Diego Gas & Electric has added two more 25-year contracts with French-based Soitec, which will supply a total of 125 megawatts from solar energy sites using Soitec's Concentrix CPV (Concentrating Photo-Voltaic solar panel modules.
In a statement today, the two companies say Soitec Solar Development will manufacture the modules in a new factory to be built in San Diego. The two local agreements follow three previous contracts for 30 megawatts of CPV-generated solar power.
(Note that the Concentrix system doesn't require water cooling.)
Will there be only one cost-competitive technology, at the end of the day?
Tracking the CPV Global Market: Ready to Fulfill Its Potential? | Renewable Energy World Magazine Article
As with all forms of renewable energy the first question anybody usually asks is 'What does it cost?'. With an emerging sector like CPV there is currently no simple answer. The big hope for CPV is that by using smaller amounts of photovoltaic material at high efficiencies it will be able to drive down costs and compete with fossil fuels - a hope shared by thin-film PV and concentrating solar thermal. At present, CPV still has some way to go, although it does have some factors in its favor. Certainly, in terms of installation costs per kW, CPV is far from the cheapest. According to GTM, the pre-profit cost for a high-concentrating multi-junction system is roughly $3.35/W installed, compared to $2.04/W for thin-film CdTe and $2.52/W for polysilicon. What really matters, though, is the cost per kWh produced, and here things are a little better for CPV - it can operate at capacity factors of up to 26 percent, compared with 20 percent for CdTe. Once that is taken into account, CPV is considered to be broadly competitive with non-concentrating PV.
As with all forms of renewable energy the first question anybody usually asks is 'What does it cost?'. With an emerging sector like CPV there is currently no simple answer. The big hope for CPV is that by using smaller amounts of photovoltaic material at high efficiencies it will be able to drive down costs and compete with fossil fuels - a hope shared by thin-film PV and concentrating solar thermal.
At present, CPV still has some way to go, although it does have some factors in its favor. Certainly, in terms of installation costs per kW, CPV is far from the cheapest. According to GTM, the pre-profit cost for a high-concentrating multi-junction system is roughly $3.35/W installed, compared to $2.04/W for thin-film CdTe and $2.52/W for polysilicon.
What really matters, though, is the cost per kWh produced, and here things are a little better for CPV - it can operate at capacity factors of up to 26 percent, compared with 20 percent for CdTe. Once that is taken into account, CPV is considered to be broadly competitive with non-concentrating PV.
I think multiple technologies may survive in different niches, e.g. I don't see CPV playing much of a role in the building-integrated market and I don't see the latter collapsing even if CPV becomes decisively the most cost-competitive on the open field segment.
Then again, Solar Millennium said just back in June that they want to build combined PV-CSP plants, with CSP on flat ground and PV on hillsides within the area of permit.
What really matters, though, is the cost per kWh produced, and here things are a little better for CPV - it can operate at capacity factors of up to 26 percent, compared with 20 percent for CdTe.
But the capacity factor is not the only factor making the difference in cost per kWh. Compared to the common fixed flat panels, CPV also requires a tracking mechanism and usually cooling, both of which result in extra maintenance costs. *Lunatic*, n. One whose delusions are out of fashion.
And the Zenith Solar system linked to above by a swedish kind of death turns the necessity for cooling from a maintenance cost into an advantage by providing both electricity and process heat from the same unit. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
This might seem contradictory, but we should not forget that political power does not only reside in owning power-production, but also in producing the machinery that collects power. As I see it PV is for the forseeable future a high-tech industry, requiring ultra-clean rooms and really expensive machinery. Like the manufacture of medicines or chemicals. Thermal solar is more akin to refrigerators, it is no piece of cake to build but it is on a lower level of technology.
The countries around the equator where sunlight is plentiful rarely have medical and chemical industry. On the other hand, there is probably more refrigerator repairmen then in rich (and therefore wasteful socities). So when it comes to global power balances I am rooting for thermal solar power because it is more likely to decentralise political power to the countries having plentiful sunlight and little power - in both senses - today. Sweden's finest (and perhaps only) collaborative, leftist e-newspaper Synapze.se
And yes, now it is developed by the west for the west. My line of thought is which branch is later easier adopted for production and usage along the equator, and my bet is on really on small thermal, which I think will benefit from advances in large solar.
Molten salt is storage and storage depends usage. But yes, if you need molten salt storage for it to make sense you are probably on a technological level where PV is as attractive as thermal. Sweden's finest (and perhaps only) collaborative, leftist e-newspaper Synapze.se
I'm not sure what you mean. If by "small thermal", you mean heat-generating solar thermal, that tecnology in fact has little to do with CSP and is really low-tech. As for CSP, I don't see how you get it small and cheap, and how you "low-tech" the receivers, generators and mirrors.
Meanwhile, even though PV is high-tech, half of production now shifted to domestic companies of low-wage East Asian countries. *Lunatic*, n. One whose delusions are out of fashion.
And of course, for the hybrid system linked to above that concentrates the solar onto a CPV module and harvests heat from that module ~ which also serves to provide the required cooling ~ the heat is more likely to be used directly, for solar Heating / AC, or solar hot water, or industrial process heat, so there is not necessarily any central thermal generator in the system. That is an especially interesting approach for urban uses in low income nations. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
Aren't all of those even more high-tech? *Lunatic*, n. One whose delusions are out of fashion.
No, I don't think the maintenance of those units is higher tech than the maintenance of the centralized systems. The reverse.
As far as keeping them maintained, a country like the DR Congo would obviously need to have a means of payment to a country like Brazil, but a country that can produce to the tolerance of modern automobiles ought to be able to produce to the tolerances of those type of thermal CSP's. I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.
by gmoke - May 16
by gmoke - Apr 22 5 comments
by Frank Schnittger - Apr 23 3 comments
by gmoke - Apr 30
by Oui - May 1713 comments
by Oui - May 15
by Oui - May 1512 comments
by Oui - May 14
by Oui - May 136 comments
by gmoke - May 13
by Oui - May 1321 comments
by Oui - May 12
by Oui - May 119 comments
by Oui - May 11
by Oui - May 109 comments
by Oui - May 10
by Oui - May 921 comments
by Oui - May 9
by Oui - May 84 comments
by Oui - May 73 comments
by Oui - May 7
by Oui - May 63 comments