Typical solar domestic hot water systems use a liquid working fluid to transfer heat from the solar collectors to the hot water storage tank. This book presents the results of a detailed investigation of a unique design and integration of electric motor and pump to circulate the liquid working fluid. The motor’s energy source is electricity that is generated from the sun by a photovoltaic module, creating an autonomous heating system. The design under review is a brushless DC motor that utilizes the magnet of a “mag-drive” pump as its rotor. This motor and pump technology, and integrated design results in both increased component utilization and increased reliability. The power switching devices of the motor perform commutation and maintain the photovoltaic module at the maximum power point. The pump magnet acts as the magnetic coupling and the motor rotor. Increased reliability is achieved through the use of solid state power electronics for commutation and the replacement of a dynamic pump seal with a static O-ring seal. This investigation reviews each major component’s characteristics under a variety of conditions to identify appropriate design choices and areas for improvement.