Design and modeling of 1-10Â MWe liquefied natural gas-fueled combined cooling, heating and power plants for building applications

Decentralized, liquefied natural gas-fueled, trigeneration plants are considered as alternatives to centralized, electricity-only generating power plants to improve efficiency and minimize running costs. The proposed system is analyzed in terms of efficiency and cost. Electrical power is generated with a gas turbine, while waste heat is recovered and utilized effectively to cover heating and cooling needs for buildings located in the vicinity of the plant. The high quality of cooling energy carried in the LNG fluid is used to cool the air supply to the air compressor. Waste heat is recovered with heat exchangers to generate useful heating in the winter period, while in the summer period an integrated double-effect absorption chiller converts waste heat to useful cooling. For the base system (10 MWe), net electrical efficiency is up to 36.5%, while the primary energy ratio reaches 90%. The payback period for the base system is 4 years, for a lifecycle cost of 221.6 million euros and an investment cost of 13 million euros. The base system can satisfy the needs of more than 21,000 average households, while an equivalent conventional system can only satisfy the needs of 12,000 average households.