A space settlement is a settlement for humans into outer space. Sustainable space settlements can be designed with renewable energy and no need for nuclear energy or over sized solar arrays. It is possible to have a space habitat part of a larger spacecraft.
There have been many designs over the years, you can see some from
NASA Ames Research Center here.
Toroidal
Bernal Sphere
More images coming
Cylindrical
More images coming
Renewable Hemp Fuel could even power Spacecraft and Sustainable Space Stations
There are space advocates that have been promoting nuclear energy to have spacecraft or space settlements powered by poisonous forms of energy that is not necessary. Renewable energy can provide biodegradable forms of energy.
There is radioactive nuclear waste from generating nuclear power that can be avoided not using nuclear energy. Remember, the nuclear power cartel sold the idea nuclear was safe, more people recognize the dangers of nuclear energy after nuclear disasters like Chernobyl.
Antimatter Future Official Website