Integrated energy systems can provide multiple products and reduce emissions with a higher energy efficiency through cascading utilization of energy. An internal combustion engine for cooling, heating and power production is proposed by feeding the exhaust gas to an absorption heat pump to satisfy the heating and cooling demands and to an organic Rankine Cycle-unit to produce power and hot water. The thermal models of components are constructed and validated. A modified techno-economic method is employed to analyze the specific cost of the energy products including a full life-cycle analysis. The result shows that the operating stage of the proposed system consumes the most of the fuel, the specific cost of electricity is the lowest 0.145 $/kWh, while the cost of cooling is the highest, 0.663 $/kWh. Compared to methods including techno-environmental and conventional methods with/without energy level, the modified method is reasonable to allocate life-cycle cost and the analysis shows that the electricity is the least sensitive one among total products, when changes the variables, such as service life and building load. This proposed techno-economic method considering life cycle equivalent emissions provide a new evaluation direction of energy systems with multiple products.
- Equivalent pollutant emissions
- Exhaust gas allocation ratio
- Life-cycle assessment
- Modified techno-economic method
- Multi-generation system