Abstract: A system is provided to change a temperature of an environment. A first plurality of containers store metal hydride, while a second plurality of containers store metal alloy capable of absorbing hydrogen atoms at a pressure less than a storage pressure of the metal hydride. Valved conduits link container pairs of metal hydride and metal alloy. When the valves are opened, hydrogen atoms desorbed from the metal hydride are transported through the conduit and are absorbed by the metal alloy. Desorption of the hydrogen cools the metal hydride containing container and heats the metal alloy containing container, which are each in thermal communication with the environment to cool or heat the environment via fluid circulation means. One or more container pairs may be operated to cool/heat the environment, while one or more other container pairs may be regenerated using a renewable power source.