Based on the actual data and needs of the Changsha Meixi Lake regional energy station project, a series of studies on the selection of project technical routes, scheme design, and equipment selection are carried out, and the evaluation indicators of the composite energy system are discussed. The methods for evaluating system design performance are researched, formulated, and verified by calculation examples. It proves that regional energy projects adopt a combination of annual primary energy utilization rate and annual system comprehensive coefficient performance for evaluation, which can reasonably reflect the system overall performance status.