In 1975, there was hope that laser fusion would be the main energy source in 20 years and would replace all power plants.
'In 1975, 10TV's Ed Ross did a report on lasers at the Battelle Memorial Institute. Ross talked to scientists about Battelle's new laser. At the time, the scientists hoped that lasers could solve all of the world's energy problems "by the year 2000." '(http://www.10tv.com/content/stories/2014/04/04/video-vault-battelle-institute-lasers-1975.html