A combined heating

power and biogas (CHPB) system driven by internal-combustion engine was proposed

in order to relieve environmental problem and the sharply increase of energy demand and domestic waste in rural areas. The system could reduce domestic waste and supply heating

power and biogas all the year around through the anaerobic digestion

internal-combustion and air-source heat pump techniques. The all operation mathematical model of the system was constructed. The system thermal performance and energy balance of supply and demand were analyzed for 5 new rural residences in Lanzhou city

about 226.8 m2 of each

as a case study. The results showed that the building loads of new rural construction

of which the heating load differs greatly between summer and winter and the power load fluctuations significantly all day long

are different from that of commercial building. The power load characteristics is not benefit for following the electrical load. The yearly average primary energy rate (PER) of the system is 37.85% considering the transformation efficiency from biomass to biogas in the anaerobic digestion

heat transfer efficiency and generation efficiency of thermal power plant. The yearly average primary energy saving (PES) index is 17.12% comparing with the conventional system in cold area of Northwest China. The results can provide theoretical basis for system scale application and promote the construction of the beautiful countryside.