| Category | 30-ton Traditional Solar + Air Energy Project | 30-ton Photovoltaic + Air Energy Project |
| One-time Investment | 450,000 RMB | 75 kW configured at 2.5 kW per ton of water, plus air-source heat pump, totaling 460,000 RMB |
| Thermal Efficiency | 55% | 0.2 (module efficiency) X 4.0 (average air energy efficiency) X 100% = 80% |
| Average Annual Operating Cost | Circulation pump runs 7 hours daily; pipeline insulation annual electricity cost: 7X1.0 kWhX0.8X365 + 10X15 kWhX60X0.8 = 9,244 RMB; pipeline maintenance cost about 2,000 RMB annually; total annual maintenance cost 11,244 RMB. During holidays when hot water is not used, the generated hot water is not only wasted but also harmful to the equipment. | No hot water needed during three months of holidays annually; power generation revenue: 75 kW X 4.2 X 90 days X 0.55 RMB/kWh = 17,355 RMB; maintenance cost 2,000 RMB. While meeting hot water demand, the remaining power generation yields an annual profit of 15,355 RMB. |
| Maintenance Rate | Pipeline leaks, insulation, signal cables, motors, etc., all require maintenance and have a lifespan. | Only electrical components and cables require maintenance. |
| Equipment Investment Return (Operation) Time | Equipment only generates value when students use hot water. Excluding holidays when students are not on campus, the annual valuable time is only about 250 days. | 365 days a year, generating value and benefits daily. |
| Benefit Generation Time | Equipment is installed ahead of infrastructure time and only put into use when students move in, realizing value. | Equipment is installed, connected to the grid, and generating electricity, producing economic benefits. |
