| Title | Development of Micro Grid Kalina Cycle System – the First Demonstration Plant in Hot Spring Area in Japan |
|---|---|
| Authors | Masatake SATO, Koji OHARA, Kazuaki ONO, Yutaka MORI, Kazumi OSATO, Takashi OKABE, Haruya NAKATA, Norio YANAGISAWA and Hirofumi MURAOKA |
| Year | 2015 |
| Conference | World Geothermal Congress |
| Keywords | geothermal power generation, small system, low-temperature system, Kalina-cycle, hot spring power generation, Japan |
| Abstract | Hot springs are a part of Japanese culture. They have various temperatures, and some of them have over 50deg.C. It is expected that utilization of the hotospring energy will be used for electrical power generation. A binary power generation technology has been used low temperature heat source. The Kalina Cycle® (Ammonia-Water Cycle) - a breakthrough technology provides strong energy conversion performance on low temperature and low brine flow rate conditions. So it is expected that the technology will be adequate for hot spring heat sources.　GERD has conducted “Development and Verification Test of Hot Spring Power Generation System” which is a commissioned project by Ministry of Environment. The program included technical development associated with power grid coordination and technical development for determining the effects to the hot springs. Designed heat source condition for 50kW power generation as an annual average is a brine inlet temperature of 98deg.C and brine flow rate of 388L/min. In order to evaluate the power generation performance of a turbine generator, a loading test was conducted by using nitrogen gas at factory. It was confirmed that the generated power was 72.5 kW of electricity with a turbine rotation speed of 50,000 rpm. The demonstration plant was constructed at Matsunoyama hot spring area, Tokamachi city, Niigata pref. in Japan, and verification testing has been conducted since 2012. Since we could not use enough brine heat source to achieve the designed performance due to protect of hot spring resource and high concentration of non-condensable gas, we improved the system to use unutilized steam and brine heat from the well and to adopt higher efficiency heat exchanger. As a result of trial test, we confirmed 44.5kW power generation. In this case, inlet temperature of heat source was lower than designed condition (98deg.C). We are trying to increase inlet heat to designed condition and to operate continuously. |