Took me about four hours, toward the end I was playing it more like a Tamagotchi (click the buttons every now and then and then leave it to rack up more power).

Also [[SPOILERS]] the ending sequence wedged after 'go be a hero', luckily when I refreshed the page it put me back to just before the black hole bit. Maybe it broke because I was on the solar system view and not the planet view or something? It worked the second time anyway.