Here are two nicely complementary videos, one from the US, one from the UK, that go into some detail on how grids balance conventional and renewable energy.
We hear the question “what do you do when the wind stops blowing/sun stops shining” from deniers hoping to capitalize on the average person’s ignorance of how the system works. Wind and Solar are “intermittent” power sources, but what many folks don’t understand is that that large traditional, fossil and nuclear plants are intermittent as well, often unpredictably so.
This recent item from the New York Times illustrates a whole new wild card that will make large thermal, especially nuclear, plants even more unpredictable in the future..
A reactor at the Millstone nuclear plant in Waterford, Conn., has shut down because of something that its 1960s designers never anticipated: the water in Long Island Sound was too warm to cool it.
Under the reactor’s safety rules, the cooling water can be no higher than 75 degrees. On Sunday afternoon, the water’s temperature soared to 76.7 degrees, prompting the operator, Dominion Power, to order the shutdown of the 880-megawatt reactor.
“Temperatures this summer are the warmest we’ve had since operations began here at Millstone,’’ said a spokesman for Dominion, Ken Holt. The plant’s first reactor, now retired, began operation in 1970.
The plant’s third reactor was still running on Monday, but engineers were watching temperature trends carefully out of concern that it, too, might have to shut down.
A spokeswoman for the regional grid control center, ISO-New England, said the shutdown had not impaired the functioning of the grid because generation has been more than sufficient. But in periods when industrial demand for electricity has been stronger, a reactor shutdown has sometimes forced grid operators to scramble.
Both videos give an inside look into how grid operators work, and how they are planning for the increasing mix of energy options that are coming in the future.
Second video, highly recommended, below:
Bruce – the thorium topic as been discussed on this blog before. Its a pipe dream. I note that the discussion on the oil drum also included a discussion of the relative merits of technology as a solution to growth and resource depletion. It is not.
http://www.youtube.com/watch?v=F-QA2rkpBSY
On the thorium topic:
Anti-nuclear campaigner Peter Karamoskos goes further, dismissing a ‘dishonest fantasy’ perpetuated by the pro-nuclear lobby. “Thorium cannot in itself power a reactor; unlike natural uranium, it does not contain enough fissile material to initiate a nuclear chain reaction. As a result it must first be bombarded with neutrons to produce the highly radioactive isotope uranium-233 – “so these are really U-233 reactors’,” says Karamoskos.
“This isotope is more hazardous than the U-235 used in conventional reactors”, he adds, “because it produces U-232 as a side effect (half life: 160,000 years), on top of familiar fission by-products such as technetium-99 (half life: up to 300,000 years) and iodine-129 (half life: 15.7 million years).
“Add in actinides such as protactinium-231 (half life: 33,000 years) and it soon becomes apparent that thorium’s superficial cleanliness will still depend on digging some pretty deep holes to bury the highly radioactive waste”.
http://charlessantiago.org/2012/06/26/lynas-thorium-waste-a-real-health-threat/