The invention relates to a comprehensive
energy system of electric, cold and thermal multi-terminal requirements, and particularly to a comprehensive-energy-
system optimization method based on doubleconstraint conditions of optimal environment emission and thermal-
exergy utilization. The method is based on constituent elements of a cold, thermal electric triple-supply
system of fired gas, a fired-gas boiler, an electric refrigerator and a photovoltaic+energy storing
system of the comprehensive
energy system, all types of market values of
greenhouse-gas (carbon) emission, benefits of environment tax saving, a
green certificate of
renewable energy and energy use right of a highly efficient fired-gas energy
station are all standardized as comparable prices through a carbon emission
accounting method based on terminal consumption and other methods according to all the elements of the system; and a system ratio interval of optimal thermal-
exergy utilization is obtained by initial derivation, and then ratio composition of all subsystems of the comprehensive
energy system corresponding to a smallest total amount of
greenhouse-gas and
pollutant emission is finally selected through
simulation, measurement, calculation and
verification on total amounts of
greenhouse-gas and
pollutant discharge. The method has the
advantage of realizing system matching degree optimization for features ofcleanness and high efficiency of the comprehensive energy system.