Solid Fuel from Oil Palm Biomass Residues and Municipal Solid Waste by Hydrothermal Treatment for Electrical Power Generation in Malaysia: A Review

Malaysia generated 156,665 gigawatt-hours (GWh) of electricity in 2016 of which the biggest share of 48.4% was sourced from coal and coke. Malaysia coal consumption was met by 90.5% of imported coal due to high demand from the power sector. Malaysia also has a vast biomass resource that is currently under-utilised for electricity generation. This paper reviews the potential of oil palm residues and municipal solid waste (MSW) for alternative coal replacement employing hydrothermal treatment (HTT). In 2017, about 51.19 million tonnes (Mt) of oil palm waste was available with 888.33 peta-joule (PJ) energy potential to generate 88.03 terawatt-hours (TWh) electricity from oil palm fronds (OPF) and oil palm trunks (OPT), empty fruit bunch (EFB), mesocarp fibre (MF), palm kernel shell (PKS) and palm oil mill effluent (POME). Meanwhile, the MSW energy potential and electricity generation potential was estimated at 86.50 PJ/year and 8.57 TWh/year, respectively. HTT with washing co-treatment eliminates the use of drying for converting range of biomass and MSW into clean solid fuel known as hydrochar. The hydrochar increased in caloric value with lower moisture, Potassium (K) and Chlorine (Cl) contents. These value-added fuels can be used as coal alternative and reduce dependency on imported coal for energy security in Malaysia.