Abstract: A system includes an anaerobic digestion tank, a gas storage tank, a power generator, a power distribution system, and an electronic control system. The anaerobic digestion tank receives biological waste from a sewer line of a multi-unit building, and allows the received biological waste to be digested to produce a combustible gas. The gas storage tank stores the combustible gas. The power generator combusts the combustible gas to produce at least one of electrical power or heat. The power distribution system receives the electrical power from the power generator, stores at least some of the electrical power, and distributes at least some of the stored electrical power to one or more electrical devices. The electronic control system controls an operation of the system.