Study of stirling-generator using alternative fuels

Abstract

The technology for harnessing power and heat from biomass fuels is already available. Electricity generation from biomass fuels currently uses the same basic technology used in power plants that bum solid fossil fuels. However, new technologies are being developed to improve power production efficiency from biomass. The potential also exists for local sources of electricity production from biomass by using small-scale gasification plants or systems involving fermentation of biomass. Multiple fuel capabilities, continuous combustion, improved torque and emission characteristics and better part load efficiency are advantages of a Stirling cycle engine. By factoring in the pollution-related environmental and social costs generated by fossil and nuclear fuels, bioelectricity is becoming a competitive energy alternative. Here a Stirling generator made by DEKA Research and Development Corp., USA was used to for small scale (1 kW DC) electricity production using biogas and LPG as fuels. The project was situated in Manikganj in Bangladesh. The study focused on performance parameters such as: fuel flow rate, air flow rate, AF ratio, brake specific fuel consumption, overall efficiency, regenerator heat input, different temperatures, engine speed, blower speed, engine power, exhaust emission qualities etc. The performance of the generator was studied using both biogas and LPG and also a comparison was made. The study revealed that the generator performed most efficiently at about 60-70% of the maximum rated load. The overall efficiency ranged 14-24%, which was higher compared to typical petrol engine generators used in this type of power range. The temperature attained in the hot end was reasonable, although it showed some drop in internal fluid pressure (He) with time. More data are needed to conclude remarks on durability of the Stirling engine.