2013-3-6 Clausius Statement of the Second Law It is impossible for any system to operate in such a way that the sole result would be an energy transfer by heat from a cooler to a hotter body. 20 Hot Thermal Reservoir A thermal reservoir is a system that always remains at constant temperature even though energy is added or removed by heat transfer. Such a system is approximated by the earth's atmosphere,lakes and oceans,and a large block of a solid such as copper. 5 2013-3-6 5 Clausius Statement of the Second Law It is impossible for any system to operate in such a way that the sole result would be an energy transfer by heat from a cooler to a hotter body. Thermal Reservoir ►A thermal reservoir is a system that always remains at constant temperature even though energy is added or removed by heat transfer. ►Such a system is approximated by the earth’s atmosphere, lakes and oceans, and a large block of a solid such as copper