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Solar Power: Take Two


I’ve said it before and I’ll say it again: solar energy and efficient use could solve all our energy problems. Nothing else can. And nuclear energy is worse than useless.

The intervening three years since the earlier posts have brought new technologies that make solar cheaper, faster, and better (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11). They’ve brought more tragic proof that nukes can never be the answer (12, 13, 14, 15, 16). They’ve brought more data showing the worsening of climate change (17, 18, 19, 20, 21, 22, 23), the mushrooming of oil wars, and the hideous hidden price of fossil fuels.

Just a couple of examples:

Rooftop solar could supply around 780 GWh of energy every day, over 280TWh per year. That estimate does not include advances that allow window surfaces (11 above), roadways and parking lots (6 above), to be turned into photovoltaic generators. It uses restrictive assumptions for solar: only 4 hours useful sunlight per day, 15% efficiency of panels, and a very narrow definition of usable space. The whole southern half of the US, from California to Virginia, gets more like 6 usable hours of sunlight per day, and in the desert Southwest, it’s closer to 9 hours.

And then there’s the image below, showing that 55% of energy produced is lost before use. (“Rejected” energy in the graph.) That’s mainly heat loss during production and transmission losses, both of which are much, much, much, much lower in distributed sources close to the end-use point. (End use suffers from its own inefficiencies. Their elimination would reduce the need for power even more, but that’s a different topic.)
chart showing proportion of fuel coming from mainly fossil sources, and 55% loss before use

The years have also brought new calculations of transition costs and feasibility. The Stanford study by Jacobson and Delucchi (2011) shows just how straightforward it would be, technically and financially, to switch to a rational energy policy.

The only real hangup is that Big Oil and Big Nuke own the government.