Check.."heat transfer fluid will heat the molten salt" but "hot fluid transfers its heat energy to water, creating steam" and "If the sun is not shining, the fluid can be heated by the molten salt." So this unspecified heat transfer fluid is nominally the direct driver for generating steam, but molten salt is used for thermal storage. Definitely if the salt solidifies, there will be a major operational problem.
What material would produce 1.3 V ?
Silicon cells produce about 0.6-0.65 V so quite a few in series are required for any usable voltage levels in power production.
In any switchers with bipolar components, at least one junction voltage drop is lost in switch Vce voltage drops, thus at least solar cell should be added to a panel to compensate for the switcher losses.
Thus the panel should have a high output voltage and hence a lot of cells, thus adding one or two cells to compensate for the switcher losses does not matter so much.
With very low output voltage panels, some low Rds FETs may have to be used as switches and rectifiers.
caster
funds.
to
ack.
in the Sahara desert IIRC.
over Europe.
snakes that live there ;-)
I read a stat somewhere (not sure where, or how true it was, but...) If the US built 91 miles square (~ 8300sq mi) of solar-thermal, it would completely satisfy our energy needs, including enough to power all our cars once converted to electric / hybrids. I believe that figure also included upgrading the transmission lines.
We have the desert southwest.... Do we have the will or desire?
Maybe we should spend the trillion dollars or so, build this thing, and finally solve the US energy problem and geopolitical destabilization problem the oil dependency causes. Though I wonder if stopping the hemorrhaging of our wealth to oil rich nations doesn't bring its own problems.
eral funds.
ed analysis.
0 kW peaknd a new
=A0(The
iquid
machines.)
he other
4x7 footFresnel
t the energy
=A0 =A0 =A0 =A0 =A0 ...Jim Thompson
and
and
of
ke it
-)
cle is
ou have
is
. . eate
Exactly right. The subsidy in Germany is what, 300%? The State pays you your investment guaranteed, plus an excellent return (from the taxpayers), guaranteed.
Oh no, my heavens, it's a _bunch_ more than that ! They pay $0.74 / KWHr!
So, it's not about going green, it's about going greed.
(If you can believe your bill, the cost-of-generation from a standard power plant is usually about $0.05 / KWHr)
But, there was a giant hole in my idea that greedy capitalists would swarm in--government keeps them out. Specifically, the power- generation industry is heavily regulated, government-controlled. Therefore, the industry has limited competition and government- guaranteed margins, which kills any drive to innovate.
Funny how, the more regulated the industry, the more screwed up it gets. (You can scarcely find more regulation that in banking, or finance, or mortgages, or medicine.)
-- Cheers, James Arthur
In the tropics, that area would receive up to 21 TW of solar energy at most during noon n the summer. Assuming 40 % Carnot efficiency for the steam turbine, thus 8.5 TW of electricity could be produced.
The US is not in the tropics, so as an annual average at noon, perhaps
7.2 TW could be produced. Due to air mass losses at low solar angles, at most 10 h/day would produce the nominal power, dropping the daily average to 3 TW. Omitting any cloudy days (concentrating power does not work when it is cloudy), still that claim sounds reasonable.However, there is not much point in building solar power that is larger than the day/night consumption variation, since then some means is required to store some energy for the night, making it expensive.
A continental wide east-west electric transmission network makes more sense by extending the usability period with some hours, rather than trying to store the energy for the night.
The fast, easy, green thing to do is just conserve. We could save a third scarcely trying, with minimal technology or technical risk.
Check out Amory Lovins' Stanford lectures--5 x 90 minutes--if you're really into it. They're excellent.
Or we could all go the Obama route and, you know, just all have less. Poor people have less energy, and, to some extent, vice versa.
-- Cheers, James Arthur
funds.
analysis.
new
machines.)
other
Fresnel
energy
You must be joking. There is VAST innovation in PV R&D and manufacturing. Companies worldwide are scrambling for a slice. The manufacturing cost of a PV is much lower than the market price because most companies are selling everything they can produce. Nanosolar is claiming $0.70 per peak Watt
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
Sahara desert IIRC.
Europe.
that live there ;-)
Ultimately PV will win out for economic reasons. Right now a sq meter of PV costs the same or more then a square meter of LCD TV screen. As the tech matures you are going to see that sq m drop to around one tenth of that price ie around 10c per peak watt.
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
This is like saying that PC power supplies will dissipate more power than the rest of the PC combined. If you want to see where the market is going on converters, look to the PC PSU market and costs for a mature and very similar example ie 5c a Watt and 80%+ efficiency
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
OOPS, this calculation is a bit too optimistic with abot 30 %. While the power reflected from a heliostat can be made to reflect nearly a constant power between 08:00-16:00 local time, in a heliostat park, the heliostats can not be mounted side by side particularity in the east-west direction, since in the morning and evening, they would shadow each other.
Thus some space must be left between the heliostats, reducing the effective capture area during noon.
So in practice, the effective collection area can calculated using the projection. i.e. multiplying the zenit power level with the cosine with the zenit angle. Even then, the capture area is still somewhat less, since the heliostats mounted at fixed locations can not reflect all sunlight falling in the area and some of the light will hit the ground.
If a naive homeowner tries to buy a synchronous inverter for a 1500 watt system, its typical retail cost (plus shipping and installation, of course) will be around $2500.
It thus gobbles gone all pv electricity sent through it and then some.
There is no reason the $2500 device should cost more than $9. Except for subsidies.
-- Many thanks, Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss: http://www.tinaja.com/whtnu.xml email: don@tinaja.com Please visit my GURU's LAIR web site at http://www.tinaja.com
Actually, there is. Charging what the market will stand. Consumer ignorance Solar Tech is an immature technology, by a long way.
I was looking at a solar water heater (not PV) a couple of years ago. The installed cost from most companies in the UK was around £1500. My estimate of the manufacturing cost plus installation was about £300. Most of which goes to the plumber.
The cost of synchronous converters will drop like a stone when they are being sold in the tens of millions through DIY stores.
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
Not so with synchronous rectifiers.
-- Many thanks,
Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss:
Please visit my GURU's LAIR web site at
ederal funds.
detailed analysis.
30 kW peakand a new
. =A0(The
liquid
d machines.)
the other
a 4x7 foot
ew Fresnel
not the energy
=A0 =A0 =A0 =A0 =A0 =A0...Jim Thompson
ap and
t and
d of
like it
:-)
cycle is
ff, you have
t is
ow.
an
,al.
are
in
tvts
state
ys
e...
I meant that power companies--those exact companies whose business is providing power--have had no special interest in innovating their product, obviously.
Of the subsidy goldmine, of course. Anything you subsidize you get more of, anything you tax, you get less of. Subsidies work. They're great for causing bubbles, and giving you a whole lot of whatever.
We're subsidizing corn-based ethanol, and we're swimming in the stuff, even though it's the opposite of green. We subsidize poverty handsomely, and reap a bumper crop of that too.
Also, $80/bbl oil makes PV more competitive today than $30/bbl.
Yeah, that's that 'bubble' thing--artificial demand, created by the subsidy. That drives up prices.
I'm not saying subsidies don't work--you can subsidize anything and get lots more of it, whether it makes sense or not: mortgages, corn- based ethanol, tobacco, socialized medicine, whatever.
PV isn't economic in the US, where we get twice Germany's insolation, yet it's economic there? What's their secret?
Calculate the PV system cost--panels, support, inverters, installation, maintenance--needed to compete with conventional generation for a) the producer and b) the consumer. It ain't pretty.
-- Cheers, James Arthur
Another emerging solution is to provide internal inverters at the panel level rather than the system level.
It is insanely easier and cheaper to switch, say, fifty watts, than 5 kilowatts.
-- Many thanks, Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss: http://www.tinaja.com/whtnu.xml email: don@tinaja.com Please visit my GURU's LAIR web site at http://www.tinaja.com
= PV isn't economic in the US, where we get twice Germany's insolation, = yet it's economic there? What's their secret?
Heavy taxes on everything else, standard european procedure.
How about $5.5 per gallon of regular gasoline?
-- Andrew
World domination! They want to return to being the world's biggest exporting nation since they were overtaken by China last year. They are investing in dominating the solar business.
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
More resilient as well. No doubt someone has already patented the idea of bundling a tiny inverter with every PV module.
-- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
"With very low output voltage panels, some low Rds FETs may have to be used as switches and rectifiers."
Hmm. I suppose it might be a silicone oil, or something like that, then. Not too many heat transfer fluids have a long life at 750 degrees, which is why I assumed it was salt. Live steam starts to come apart well below that, iirc, which causes hydrogen embrittlement of everything.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.