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Solar Tree Bears Fruit
Hugh Pickens writes "A prototype solar tree that recently went on display on a busy street in Vienna, Austria has passed a key test by providing light during the night-time even when the sun had been blocked by clouds for four days in a row. The branches of the solar tree were decorated with 10 solar lamps, each one powered by 36 solar cells. The tree included rechargeable batteries and electronic systems to measure the amount of light in the atmosphere and trigger the solar lamps to go on. 'Not just trees but other objects could be decorated with solar cells and so keep streets well lit at night time,' said Christina Werner from Cultural Project Management. Google uses a similar concept to light their parking lots with 3,000 solar panels that provide up to 10 percent of the Googleplex's power demand. We discussed Google's solar initiative last year."
I believe Vienna is in AUSTRIA.
I want to delete my account but Slashdot doesn't allow it.
So long as fossil fuels are being burned to make power during the day, it is far more efficient to take the daytime output of the most cost-effective possible panels (usually nice unimaginative rectangular ones that mount on existing roofs or new carport structures) and feed it directly to the grid to reduce the load on the inefficient plants that peak during the daytime. There is no reason to lose a major chunk of the power charging batteries, to build expensive battery arrays or to build bizarre structures to support the cells.
At night, the worst power plants are throttled back or shut down and the most efficient plants are handling the load.
When no further fossil fuels are used to make daytime power, then storing electricity from daylight becomes interesting and, even then, batteries are a loser.
Well, the point of the article is that these things are working after 4 days in a row with almost no sunlight. Sounds reasonably robust to me.