Saturday, May 11, 2019

Semi-review: Let It Shine - The 6,000 Year History of Solar Power

Short version of my review of Let It Shine: go read it, even if like me you're not interested in passive solar architecture. It's ironic that passive solar isn't that interesting to me, because it's about half of the book and until the last century it was about the only truly successful harnessing of the sun. Everything else, however, is still interesting enough to make this a good book about the history of solar power.

The history of solar water heating is fascinating - it got pretty far, particularly in Japan, before being killed off by cheap fossil fuels. In some alternate universe timeline, solar motors, solar water heaters, even solar electric modules developed in the late 1800s were never replaced by coal and fossil fuels.

Solar electric was particularly interesting to me. They have a picture of the first photovoltaic array in New York City, in 1884. PV energy seems like it could have taken off earlier than it did - the Eisenhower Administration purposefully rejected it compared to nuclear power and the mirage that atomic batteries would be commonplace.

The early space race, OTOH, was a godsend for PV as the only feasible long-term power source for the small satellites they used at the time (I'm not sure when radioisotopes became an alternate power source). The Gollum of 20th Century climate change even makes an appearance. A design for the first proposed American satellite from 1955 "shows that the satellite's designer, Dr. S Fred Singer, planned to use solar photovoltaics as its power source."

PV's cost hardly mattered for satellites but they helped pay for early technological development. Soon afterwards, remote locations on earth also became obvious use cases (irony again, offshore oil platforms started it). PV poked along for a while while subsidies for nuclear power and fossil fuels burgeoned forth, and PV received little R&D. The Atomic Energy Commission in 1973 proposed a 5-year research budget of $4 billion for nuclear and $36 million for solar. The Reagan Administration purposefully neglected solar. It took massive subsidies in Germany and piggy-backing on computer chip technology for PV to really begin its takeoff.

One interesting lesson from the book (mainly from discussion of solar motors and solar water heating) is how much of technological development is iterative development of prior work. The statement that science relies on standing on the shoulders of giants applies just as well to engineering.

Again I'd recommend the book. I'd also be interested in a history focusing exclusively on solar PV, and another on wind power. Suggestions welcomed!

7 comments:

David B. Benson said...

Brian, look at the articles in the "Encyclopedia of Energy".

THE CLIMATE WARS said...

Rchard Rhose new book reveals some curious facts about early silicon pv-- it relied on semiconsuctor industry reject wafers for feedstock.

THE CLIMATE WARS said...

I meant to spell him like the Colossus

Jan Galkowski said...

They didn't necessarily have a technology proposal, but both Tesla and Edison were enthusiastic about the prospects of harnessing solar energy to produce electricity. They just had the physical insight that there was all this free radiation pummeling the surface of the planet, and it seemed a shame it should go to waste.

There were probably others who had similar ideas.

Supernaut said...

Thanks. Wrt the sentence "The early space race, OTOH, was a godsend for PV as the only feasible long-term power source for the small satellites they used at the time (I'm not sure when radioisotopes became an alternate power source)"

It's mainly a question of distance from the Sun. Most Earth-orbiting satellites are powered by solar arrays (where you're exposed to a nice ~1.4 kW/m**2). In solar system exploration, the 'fuzzy' dividing-line is the neighborhood of Jupiter: there's currently a NASA orbiter around it called Juno and it uses (massive!) solar arrays. Depending on the mission, you may want to do trade studies to see which is more convenient at Jupiter, if PVs or RTGs. Certainly beyond Jupiter you switch to radioisotopes/RTGs. Cassini, which until the end of 2017 orbited Saturn, used radioisotopes (you may or may not recall some ill-informed people -including some who should have known better - protesting the launch of Cassini in 1997 b/c of RTGs). New Horizons, which did a flyby of Pluto-Charon system also uses RTGs, as do the ever-more-distant but still functioning Voyager probes.

BBD said...

A design for the first proposed American satellite from 1955 "shows that the satellite's designer, Dr. S Fred Singer, planned to use solar photovoltaics as its power source."

Well, well. Dear old S. Fred, eh?

Brian Schmidt said...

Supernaut - I remember when experts said that solar power couldn't be used beyond the asteroid belt. I wonder if we'll see it used in systems going to Saturn eventually.

I went and looked it up - first satellite using RTGs was in 1961, so solar panels didn't have a huge headstart. Still, however expensive solar may have been at the time, it was probably cheaper and lighter than RTGs.