Swinburne University of Technology Sarawak Campus

Best source of renewable energy

September 4, 2019

by Dr Hadi Nabipour Afrouzi

Borneo is the largest island in Asia and it is also the third largest island in the world. Covered by some of the oldest rainforests and located right on the equator, renewable energy solutions to generate electricity is highly possible in this great island.

In this article, three renewable energies namely solar, hydro and biomass are chosen as the most suitable sources in terms of area requirements, energy production efficiencies, availability of resources and other considerations such as environmental impact, as well as time and cost of installation of mentioned energy generation facilities.

In general, solar energy has advantage over the rest of the sources in terms of area requirement as solar panels are often installed on rooftops, thereby minimising the space required. However, on-grid solar farms which is another method of solar collection is an exception, because it requires a large area for higher and larger generation of energy.

Meanwhile, hydropower offers the option of micro-dams that are already being constructed in certain rural areas with limited power source. Although regular size dams like the Bakun Dam is able to provide electricity for the whole village at one time, the area requirement can be massive. For biomass, a large area is required to store raw materials and for the production of biofuels such as ethanol and biodiesel. Hence, when considering the physical area range and requirements in Borneo, solar and hydro are the two most suitable renewable energy sources.

Efficiency of the energy source is as equally important as production whereby the focus is on having maximum output with minimum input. With area and efficiency being interrelated to one another, it can be observed that the highest possible efficiencies of the sources require minimal area to generate sufficient energy for the location of interest.

Solar panel efficiencies may have improved over the years although they are still not very efficient at converting the sun’s energy into electricity. This is because most solar panels have efficiencies ranging between 15% to 20% only. Comparing to solar energy, hydropower is relatively more efficient. Depending on the type of hydro turbines installed, the modern hydro turbines can convert as much as 90% of the available kinetic energy in flowing water into electricity.

As for biomass, the efficiency of biomass energy production depends mainly on the various biochemical and thermochemical methods used for its conversion. The biomass energy is about 75% to 80% efficient when used for heat or heat-led combined heat and power (CHP), and only 20% to 25% efficient when used for electrical generation. It is even less efficient overall when used to convert into liquid fuels for transportation applications. Thus, hydro energy is deemed the most efficient among the three discussed sources.

Other than efficiency considerations, the availability or the abundance of raw materials of the sources is another significant factor to consider. Situated right on the equator, the average solar irradiance that Borneo receives is undoubtedly higher and more consistent than most countries, leaving solar power generation an excellent option in terms of availability.

On the other hand, the potential of hydroelectric power generation is also high since it is possible to build small-scale hydro dams near the plentiful river systems across Borneo. However, it may not be a viable option in terms of availability after all due to the potentially large fluctuations in water source as a result of variable rainfall during different seasons.

The fuel or resource for biomass is largely abundant due to the wastes from palm oil extractions. However, as the resources are scattered throughout Borneo, the collection and transportation mode for oil palm compost need to be taken into account. Alas, solar energy is still considered as the most convenient and suitable source.

Another consideration is the potential environmental impacts. For solar energy, hazardous chemicals are used to clean the semiconductor cell surfaces of the solar cells during manufacturing stage. These chemical waste would badly affect the environment and cause serious health problems if they are not properly disposed. Due to the need to build dams, hydropower has the potential to destroy a large area of the forest. Lastly, in selecting biomass, it includes the preparation for energy conversion process, material handling systems as well as in-depth evaluation of the available quantity of a given agricultural resource.

As can be clearly observed, many aspects are to be considered before a renewable energy source could be deemed suitable in Borneo. In fact, solar energy is the most suitable source due to its ease of installation on rooftops, large potential for future improvements in efficiency, availability of sun all year long, and less negative impacts on the environment.

Hadi Nabipour Afrouzi is an engineering lecturer from the Faculty of Engineering, Computing and Science at Swinburne University of Technology, Sarawak Campus. He can be reached via email at HAfrouzi@swinburne.edu.my.