Impacts of Multiple Distributed Generations on a Weak Distribution Network - A Case Study

Abstract

It is well known to electricity authority worldwide of difficulty in meeting an ever increasing demand of a rural load center tens to hundred kilometers away from the interconnected grid. In many cases, upgrading sub-transmission system seemed appropriate in technical, economic and environmental aspects. Nevertheless, there are cases where addition of local generation is the only means to meet the increasing demand. For more than ten years, Thailand's Provincial Electricity Authority has been tackling complications of adding more and more local generations until exceeding the local off peak demand. These generations consist of four small hydro, one geothermal and one fuel oil power plants. Unfortunately, the unplanned attempts made to resolve problem concerning provision of electricity supply to meet the demand without conducting any pre-engineering study had proved ineffective and sustainable solution could not be attained. This paper described, analyzed and discussed in details the development of PEA's distribution system planning to supply quality and reliable electricity to a small rural and remote community in the country Northern province. Extensive field surveys and technical analyses were carried out to investigate impacts of distributed generation on the performance of the network. Finally, recommendations were given as guideline for further study in search of feasible and sustainable solutions.