A heat transport system includes a fluid, a heat engine, and a component. The fluid has a first fluid region at a first temperature and a second fluid region at a second temperature that is different from the first temperature. The heat engine includes a shape-memory alloy disposed in contact with each of the first fluid region and the second fluid region. The heat engine is operable to transfer heat from one of the first fluid region and the second fluid region to the other of the first fluid region and the second fluid region in response to the crystallographic phase of the shape-memory alloy.