Uranium is present in coal in high enough quantities that a coal plant releases more uranium to the environment then an equivalent nuke plant burns in its reactor, and mining for materials for solar panels creates literal mountains of thorium salts and other thorium contaminated debris.
Nuclear plants have the unfortunate position that they actually have to manage their nuclear waste due to its concentration. It’s not actually hard to store the waste permanently from a technical perspective, it’s just difficult to have the political will to actually do it.
Heat pump could heat your house if it’s near 0K “outside”. Heat pumps are how we chill to near 0K anyways. And by heat pump I mean literally a window air conditioner. Replace the freon in your typical AC with helium and get a really fancy evaporator (cold head or cold finger is the trade term) and you could probably get a 10cc vial on the end to sub 70K. With vacuum and a bigger 240V window AC unit you can get near 4K. Running multiple heat pumps in stages and with liquid nitrogen as coolant for some of them and you can condense helium and push really close to 0K.