The present disclosure provides for hyperloop vapor cycle environmental control systems (ECS) and related methods. More particularly, the present disclosure provides for hyperloop vapor cycle environmental control systems and methods, with the hyperloop vapor cycle environmental control systems and methods configured without a compressor needed to pump a refrigerant through the system and configured without a condenser heat exchanger needed to condense gas refrigerant to a liquid to reject the heat of compression of a compressor to the ambient atmosphere. Since there is no need for a compressor, the example hyperloop ECS of the present disclosure requires only a small fraction of the electrical power of a standard vapor cycle air conditioning system. Power is needed substantially only for the ECS controller and some various valves.