Abstract:
The Electricity system load profile of Sri Lanka has a high evening peak demand and
as a result has a low load factor.
The load curve has a close relationship with the human behavior and other economic
activities of the country, having a morning peak, Day peak and a night peak. Even
though it is desirable to have a flat load curve, due to this behavioral impact, the
curve is having rather large variations. The extent of variation is so substantial that
the maximum demand is having a greater value, which is about 2.24 times of the
minimum demand.
During the dry season water level of the large hydro reservoirs is getting decrease
rapidly and system demand fulfill by thermal generation of CEB and Private Power
Plants. Therefore most of the high cost small thermal generators should be operated
in the evening peak hours. Hence, CEB has to pay additional cost for power
generation than income earns from electricity selling to the customer.
That reason is happened to fulfill the peak demand using high cost thermal
generation. The objective ofthis feasibility study is prepared the system ofscheduled
running for existing mini hydro power plants to reduce high cost thermal generation
at evening peak hours. The study has contained the energy mix of Sri Lanka,
behavior of thermal generation in future, present mini hydro running pattern,
possibility of schedule running of existing mini hydro plants and prepare the
generalized system to operate mini hydro plant for schedule running.
According to the results, some of mini hydro plants in the existing system can
operate under the scheduled running and the results of scheduled mini hydro plants
have affect to reduce high cost thermal generation by small thermal generators.