How much space does solar energy take up?

Solar energy in itself does not "take up" space. Any and all light that is emitted from the sun is "solar energy". When a photovoltaic cell is used to convert solar energy into solar electricity, the energy can be stored in a battery or capacitor, which will be able to contain the same amount of solar electricity as it would with DC power from any other source. The collection of significant amounts of solar electricity, on the other hand, requires a fairly large amount of surface area or "space"; If the technology were perfect, and 100% efficient, energy would be collected at roughly 1Kw per square meter of photovoltaic cell. Unfortunately only state of the art and very expensive solar panels can even achieve 60% of this, so a more realistic figure is 350 watts per square meter. Also, one must take into account that the sunlight will not hit your location 24 hours a day...