RENEWABLE ENERGY HYBRID POWER SYSTEMS AT TOTALLY PROTECTED AREAS IN SARAWAK

MOHAMMAD AMIN BIN MOHAMMAD JA'FAR¹

The development in the technology for producing electric power with renewable energy such as solar, wind and water in the past years have made a real "energy revolution" possible in the next decade. Renewable energy hybrid power systems use renewable energy (wind and solar) to charge batteries, with diesel or petrol generators as a back-up and peak load power source. The system includes a high-sinewave inverter, battery charger and power booster, which is microprocessor controlled.

Renewable energy hybrid power systems were first introduced in Sarawak’s Totally Protected Areas in 1996. The system can meet the needs of the staff manning remote stations for lighting and running computers, communication systems and scientific equipment. Installing these systems at remote stations helps to reduce pollution and limits the production of greenhouse gases responsible for global climate change.

Current Situation
To date, the National Parks and Wildlife Division has installed these systems on four off-shore islands and one of them, Pulau Talang Kecil, was included in this study. The systems installed at this station use solar power and generator back-up, whereas at Tanjung Datu National Park and Samunsam Wildlife Sanctuary both solar and wind power are used. With these systems available, all these stations have 24-hour electricity supply.

A range of approaches was taken in gathering information, including:

• inspection and observation of management of the system,
• interviews and discussion with the Park Wardens and staff manning the system,
• checking and reviewing maintenance records, cross-checked with the operating handbook (CASE, 1996),
• interviewing technicians from James Electrical & Construction Works, who had installed some components and done minor repairs.

In addition, advice and constructive ideas were sought from the electrical experts involved in the installation of these systems, in order to evaluate improvements which are practical and feasible.

STUDY SITES

The study was conducted at three remote stations: Tanjung Datu National Park, Samunsam Wildlife Sanctuary and Talang Kecil island in Talang-Satang National Park. Three different sizes of the renewable energy hybrid system are installed at the three stations studied.

Tanjung Datu National Park (48 volt system)
The system installed in 1996 is a switched hybrid system with solar panels (photovoltaic arrays) and wind turbine and a 7kw diesel generator. When first installed the system worked very efficiently, providing power for three to five days without starting the generator.

Samunsam Wildlife Sanctuary (110 volt system)
The system installed here is the largest of all the systems at the seven stations, and works on 110 volts, whereas the other stations are either 24 or 48 volts. The system here also includes solar panels and wind turbine and two 20kw diesel generators as back-up power.

Pulau Talang Kecil (24 volt system)
The system installed at this station is the smallest version of the system, with solar panels and a 3kw petrol generator, but no wind turbine: at this station, the wind speed is very low, so it is not practical to install a wind turbine. The system still efficiently provides electricity 24 hours a day.

The running costs for the renewable energy systems and diesel generators over one year, based on the data in the maintenance records at the three stations, are shown in table 1.

Table 1 : Actual costs of diesel generators and renewable energy system

Cost of renewable energy systems
Based on the data in Table 1, an estimate of the costs of running renewable energy systems and conventional diesel generators for twenty-four hour power supply of 3.5kw capacity for five years was made, as shown in Table 2. The difference in running costs over five years is MYR 105,500, with the renewable energy system being much more economical over the period.

Table 2 : Estimate for 5 year period:

Problems
Two out of three of the systems were not working because of battery problems. Deep-cycle batteries are needed, which is the most common type used for energy storage but they are not available in Sarawak. This problem could be solved if replacement batteries were stocked locally. Lack of sunlight or wind is not really a big problem since there are diesel or petrol generators available as back-up power.

For the past few years, the National Parks and Wildlife Division has been expanding provision of facilities and amenities to meet the needs of staff and visitors at the stations. If all the remote Totally Protected Areas were equipped with this kind of new technology, the conservation impacts of management and tourism could be reduced.

Renewable energy hybrid power systems are already widely used all around the world. The need for more efficient alternative means of generating energy should be further explored, so as to improve the quality of the power supply in remote Totally Protected Areas of Sarawak while minimising impacts on the ecosystem.

CASE – Centre for Application of Solar Energy (1996) Renewable energy power system operating handbook, Synergy Power Corporation Pty.Ltd.