Furnaces, use a huge array of mirrors
to concentrate the Sun's energy into a small space
and produce very high temperatures.
Cells (really called
"photoelectric" cells) that convert
light directly into electricity. In a sunny climate, you can get enough power to
run a 100W light bulb from just one square metre
of solar panel. This was originally developed in order to provide
electricity for satellites, but these days many of
us own calculators powered by solar cells.