What fossil fuel does solar energy replace?
Solar energy produced only 0.1 percent of US total electricity in 2006, so it is hardly replacing anything as yet in that total. More solar energy is captured by individual houses and used for water heating and possibly space heating, not in photo-voltaic cells. This partially replaces whatever that particular house normally uses. Might be natural gas or liquefied stored gas, might be coal, might be electricity. If the latter, this will have been generated mostly from coal and natural gas, with some 20 percent nuclear.
