ENERGY MANAGEMENT IN ISLAND MODE WITH SYSTEM POWER CONTROL DEMAND RESPOND

Abstract

This study aims to manage the Island mode via power control demand respond system for the operation building of Kamphaengphet Rajabhat University. The Demand Response (DR) and Building Energy Management System (BEMS) are applied in order to plan the automatic electric supply and respond to the needs of the electric usage between loads and power supply appropriately. It helps reducing the cost to reserve the electric during the Peak Period and loads within the building including light bulbs, air cooling fans, portable speakers, notebooks, projectors and refrigerators. According to the analysis of electric usage in the building, discovered that the electric usage in one day is used 9.89 kWh. The average of electric usage needs of the loads is equally at 0.41 kWh and the need of electricity usage is seven hours per day. The usage occurs between 08.30-12.00 a.m. and 01.00 -04.30 p.m.  Its usage average is 1.24 kWh. The least electric usage is 0.22 kWh, occurring one hours during lunch break which is between 12.00-01.00. The researchers applied the algorithm theory developing along with the controlling set with microcontroller Arduino Mega. The result determines that the operation of power control demand respond system will evaluate the electric supply. Then it examines the usage needs of the load.   Without the need of load usage, the system will reserve the solar and wind energy in the battery backup.               If the load is requesting energy, they system releases the solar energy as the first source. If the load still requires more energy than solar energy could produce, the system will release the wind energy as the second supply. In case the electric usage is still required more energy than those two sources provided, the system will examine the electric from battery backup and supply to the loads. If the load still needs more energy, the system will release the electric power from diesel generator. The system will deliver the message to turn off the load if necessary. Without turning the load off, the system will show overload result immediately. In order to manage energy in island mode with four power sources, all loads can be turned on for 5 hours continue.         The overall electricity is equally at 6.91 kWh which is 1.76 kWh from solar energy, 0.68 kWh from wind energy, 3.60 kWh from battery backup and 6.91 kWh from diesel generator. When the load increases over 5 hours, the microcontroller kit will limit the electric devices using only light bulbs, projectors, portable speakers and portable computer so it is adequate for the power supply. However, the size of solar cells is increased into 4.25 kw, it will produce enough energy 7 hours continually for all loads. It can save energy from diesel generator around 15.92 percent.