This chapter consists of two sections, ‘Energy Cost of an Independent Microgrid with Control of Power Output Sharing of a Distributed Engine Generator’ and ‘Improvement of Power Generation Efficiency of an Independent Microgrid Composed of Distributed Engine Generators’. In the 1st section, small kerosene diesel-engine power generators are introduced into an independent microgrid, and power and heat are supplied to 20 houses. If the proposed system is introduced into a community with little heat demand, effectiveness will decrease greatly. The 2nd section investigates the power generation efficiency and power cost of an independent microgrid that distributes the power from a small diesel engine power generator. When the number of distributions of the engine generator is installed, the cost of the fuel decreases.
TopGeneral Introduction
In the 1st section, small kerosene diesel-engine power generators are introduced into an independent microgrid (IMG) that connects 20 houses, and power and heat are supplied to them. A 3 kW engine generator is installed in six houses, and a boiler and a heat storage tank are also installed, and exhaust heat to make up for insufficiency is supplied. The boiler is installed in the house that does not install the engine generator, and heat is supplied to the demand side. Partial load operation of the engine generator has a large influence on power generation efficiency. Therefore, this study discusses the system that controls the power of the engine generator by the power distribution control system using the genetic algorithm (GA), and the control system that changes the number of operations of the engine generators according to the magnitude of the power load. As a case study, the energy-demand model of the 20 houses in Sapporo was analyzed. As a result, the annual energy cost of the number of operations system and the power distribution control system is reducible with 16% and 8% compared with the conventional method, respectively. However, it depends for this cutback effect on the heat demand characteristic greatly, and when the proposed system is introduced into a community with little heat demand, effectiveness will decrease greatly.
The summary of the 2nd section is as follows. The power generation efficiency and power cost of an independent microgrid that distributes the power from a small diesel engine power generator was investigated using numerical analysis. The fuel consumption of a small diesel engine and the relation between power generation and heat power were obtained in experiments using a prototype. The independent microgrid built using one to six sets of 20 average houses in Sapporo and the distributed engine generators were examined using these test results. However, the operation of a diesel engine power generator controls the number of operations according to the magnitude of the power load of the microgrid. When a diesel engine power generator is distributed, since the power generation capacity per set decreases compared with the central system, the load factor of each engine generator rises. As a result, the operation of an engine at partial load with low efficiency can be reduced. When the number of distributions of the engine generator increases as a result of numerical analysis, the cost of the fuel decreases. However, when the rise in facility cost is taken into consideration, the number of engine generators for distribution is in fact 3 or 4.