The present invention pertains to systems, methods, and compositions for liquid phase change, including for active cloud point, e.g., critical solution temperature, adjustment and heating or cooling, e.g., refrigeration, cycles. In some embodiments heat is absorbed, released or both due to phase changes in a liquid system. Advantageously, the phase changes may be controlled by controlling the ingredients or amounts of certain components of the liquid system. Advantages may include lower capital expenditures, lower operating expenses, or both for a diverse and wide range of heating and cooling applications. Such applications include, for example, cooling of data centers, cooled transportation of goods, refrigeration, heat pumps, extractions, ocean thermal energy conversion, and de-icing of roads to name just a few.