Cooling systems using adsorption are described. The cooling systems use an adsorption cycle without continuous heat input and over a long duration. The cooling system can function by vaporizing a liquid at a reduced pressure. The cooling systems have applications in developing countries, in both arid and non-arid regions, allowing, for example, for the operation of refrigerators and small air conditioners without electrical input. The cooling systems can be used for cold storage. The cooling systems can present a greener alternative to conventional cooling methods in developed countries.