I wrote:
In Japan, at least, PV is now nearly competitive with centrally
generated power, and even though it is no longer subsidized, PV roof
installations are becoming very common in sunnier locals. No doubt
there are places in Japan where Stirling systems could be installed,
but the opportunities are not as good as, say, southern California
or Nevada. Japan also lacks suitable wind and suitable locations for
wind turbines, although there are a few here and there.
Another big problem with Stirling or solar trough in Japan has been
demonstrated in the last 24 hours. A major typhoon is crossing the
western end of the country. Typhoons are nowhere near as violent as
US tornadoes, because they are spread out over such a large area.
They come as regular as clockwork every year. They seldom kill
people, but they often blow over light structures with a large
surface area, such as greenhouses and billboards. I expect the
average typhoon would make mincemeat of the Stirling solar devices I
have seen on the web.
Typhoons do not generally destroy rooftop solar water heaters or PV
collectors, because they are flat and tightly secured to the roofs. I
have seen a solar water heater pulled off the roof and smashed by a
medium-sized typhoon. They do not destroy wind turbines because the
blades automatically feather in high winds.
Maybe these machines are tougher than I imagine, because they work in
the Mojave after all . . .
In other solar news, Wikipedia says that the SEGS now in place in the
Mojave produce 354 MW, and PG&E has signed a contract to build a 553
MW more by 2011. Below that it says Southern California Edison is
building a 500 MW stirling solar dish system there with Stirling
Energy Systems (SES), and SES has announced an agreement with San
Diego Gas & Electric for systems that will produce "between 300 and
900 MW." So, SES is making good progress and more power to them. See:
http://en.wikipedia.org/wiki/Solar_power_plants_in_the_Mojave_Desert
http://www.stirlingenergy.com/breaking_news.htm
SES says the capacity factor is 23.9%, which compares unfavorably
with wind turbines. I assume this is because it does not produce
electricity at night. This is less of a problem in southern
California than it would be elsewhere because I think their peak
demand for electricity is for air-conditioning during the day, and of
course they need air-conditioning most when the sun is shining. Wind
does not follow peak demand as closely.
The Solar One solar-thermal facility in Nevada produces 64 MW from 300 acres:
http://news.zdnet.com/2100-9595_22-6166113.html
I believe that compares favorably with wind when measured by the
entire land area (300 acres), but less favorably when you look at
only the "footprint" of the machines. In other words, wind towers
take up little space on the ground, leaving plenty of space for cows
to graze. But you cannot put wind towers close together, or one will
"steal the wind" from the other, as sailing ship captains used to say.
- Jed
