Introduction to Trigeneration

Trigeneration refers to the simultaneous generation of electricity and useful heating and cooling from the combustion of a biomass fuel or a solar heat collector. Conventional coal or nuclear-powered power stations convert only about 33% of their input heat to electricity. The remaining 67% emerges from the turbines as low-grade waste heat with no significant local uses so it is usually rejected to the environment. What is Trigeneration In a trigeneration system, the supply of high-temperature heat first drives a gas or steam turbine powered generator and the resulting low-temperature waste heat is then used for water or space heating. Such systems can attain higher … Continue reading

District Cooling Perspectives for the Middle East

District cooling produces chilled water in a centralized location for distribution to buildings like offices and factories through a network of insulated underground pipes. The chilled water travels to different buildings, where the water circulates through refrigeration coils or uses absorption technology to enter the air-conditioning system. During winter, the source for the cooling can often be sea water, so it is a cheaper resource than using electricity to run compressors for cooling. What is District Cooling District cooling provides effective control over internal temperature of a building, requires less maintenance than a standalone air-conditioning system, consumes lesser space and … Continue reading

Waste-to-Energy Pathways

Waste-to-energy is the use of modern combustion and biological technologies to recover energy from urban wastes. The conversion of waste material to energy can proceed along three major pathways – thermochemical, biochemical and physicochemical. Thermochemical conversion, characterized by higher temperature and conversion rates, is best suited for lower moisture feedstock and is generally less selective for products. On the other hand, biochemical technologies are more suitable for wet wastes which are rich in organic matter. Thermochemical Conversion The three principal methods of thermochemical conversion are combustion (in excess air), gasification (in reduced air), and pyrolysis (in absence of air). The most … Continue reading

Combined Heat and Power Systems

Combined Heat and Power (CHP), or Cogeneration, is the sequential or simultaneous generation of multiple forms of useful energy (usually mechanical and thermal) in a single, integrated system. In conventional electricity generation systems, about 35% of the energy potential contained in the fuel is converted on average into electricity, whilst the rest is lost as waste heat. CHP systems uses both electricity and heat and therefore can achieve an efficiency of up to 90%, giving energy savings between 15-40% when compared with the separate production of electricity from conventional power stations and of heat from boilers. CHP systems consist of … Continue reading