Evaluation of technologies for energy from biomass and waste

This project aimed to assess various technologies for generating energy from biomass and waste in Indonesia.

The objectives of this project included:

• To identify the types and quantify of fossil fuels that can be substituted by biofuels.
• To characterise the available biomass and waste.
• To identify the suitable technologies.
• To identify future research avenues.

The project combined literature review, data collected from secondary sources (national and regional level institutions in Indonesia), and some primary data collection from limited survey. The long-range energy alternatives planning (LEAP) system was employed to model the Indonesian energy mix and forecast energy demand up to 2025.

The technological assessment of biomass for energy was extended to economic valuation of the resource itself. This economic valuation was considered necessary since technological assessment is tightly linked to economic value. The data was grouped into three regions, namely JAMALI (including Jawa, Madura, Bali), Western Region (including Sumatra, and Kalimantan), Eastern Region (including Sulawesi, Maluku, Papua). Studying the distribution and type of biomass and waste in those regions helped identify potential technologies to be applied. For instance, oil palm, its processing wastes and forest residue are the potential bioenergy feedstocks. These are more available in the Western Region, while agricultural waste and manure are more available in JAMALI. The conversion technology in those regions will be also be different. Recommended technologies were listed, and outcomes were communicated in the form of two papers.

Researchers investigated the the biomass and waste available, as well as social, financial and environmental considerations. This project is relevant as Indonesia is currently a net fossil fuel importer, but possesses abundant biomass and waste that could be exploited for power generation. Moreover, Australia has homegrown technologies, expertise and best practices in utilising biomass and waste as energy sources. Combining the lessons learned in Australia with Indonesian expertise, the project provided potentially valuable information to Indonesian energy policy makers, as well as refining the applicability of Australian technologies in the developing countries.

Estimates of total potential forest biomass resource as feedstocks for bioenergy in 2013 ranged from 104 to 177 petajoules, with an average of 132 petajoules. About 50.4 per cent was from harvesting residues and the remainder from wood processing residues. Riau province has the largest potential bioenergy, followed by Central Kalimantan, East Kalimantan, East Java, South Sumatra, Central Java, and Jambi, which together accounted for 87 per cent of potential bioenergy. Moreover, three major islands accounted for 95 per cent of total potential bioenergy. They are Sumatera, Kalimantan, and Java (in decreasing order). The economic value of pelletised forest biomass was estimated to be about US$5.60 per ton of wood residues. The economic value of forest biomass is more sensitive to changes in the price of wood pellet than to changes in the collection and hauling cost of wood residues.

The results suggest that substituting liquid biofuels for fossil fuels in various applications, including electricity generation, could contribute up to 23 per cent of liquid fuel consumption by 2025. The use of solid biofuels and waste in electricity generation could provide up to 1091 of the 6190 petajoules required to produce electricity. This is a saving of approximately 7.2 per cent in solid fossil fuels. Liquid and solid biofuels combined could contribute up to 24 per cent of the national primary energy mix.

Detrimental environmental impact could potentially occur, however, as biomass plantations would require a significant amount of land, about 22 million hectares. On the other hand, this could offer employment opportunities to about 14 million people, both in utilising waste and retrofitting current fossil fuel power plants, mechanical and chemical process machinery.

As the majority of power plants are located in the JAMALI region, while liquid and solid biofuel resources are in the Western and Eastern regions, further analysis would be required if the scenario were to be implemented. Moreover, not all areas of Indonesia are suited to growing oil palm, and population is not distributed evenly. Future work with the Indonesian LEAP model to detail locations for plantations and distributed power plants, as well as identifying regions’ energy demands, should provide more precise estimates.