This was a paperback book with a special library binding to make it more durable. This is the first in the series that was paperback. This is the last in the sub-series about fuels, which also includes nuclear power, oil, and coal. Like the others, it is fascinating. I think they should be a necessary read in any environmental science class so that the question of how power is supplied and why would not be skipped. Science fiction authors ought to read these too.

Detailed Review:
1. Sunlight
The nature of light and sunlight. The greenhouse effect as it relates to actual houses and greenhouses.

2. Mirrors and Hotboxes
Mirrors can concentrate the rays of the sun and start fires, especially if they are parabolic. A hotbox is a very effective greenhouse which can be use to cook your food or even to run a steam engine.

3. Hot Water
Hot water is good stuff but hard to come by. In the early 1900s, solar water heaters for the home were quite the thing, but they were superseded because of the convenience of other means of heating water.

4. Nuclear Power and Oil
High hopes for nuclear power and convenience of oil reduced interest in solar power during the early and mid 1900s.

5. Solar Cells
In 1873 it is discovered that selenium conducts electricity when exposed to light, i.e., it can convert light into electricity. It is inefficient, though, only 1%. This is enough to power electric eyes that cause doors to be automatically opened for people. Silicon also turned out to be photoelectric and could be improved up to about 16%. This made them worthwhile in applications like space stations, and those signs at the side of the road. But for non-niche applications, solar power is still pretty expensive (note that this book was published in 1981, and things do seem to have changed).

6. Deserts and Space
This is the chapter about the future, in which Asimov makes good arguments for a solar power station in space and David Wool provides some pretty good illustrations. ( )