Aston University scientists are to start a project to use biomass from Indonesia’s unwanted rice straw for low-cost, commercial-scale energy.
Scientists from Aston University’s Energy and Bioproducts Institute are to start a project to convert Indonesia’s unwanted rice straw into low-cost, commercial-scale biomass energy. The country produces 100 million tonnes of rice waste annually, and 60% of this is burned in open fields, causing air pollution that has been linked to lung cancer. The amount burned is equivalent to around 85 terawatts of electricity – enough to power Indonesia’s households ten times over. The project is set to develop processes that can capture more affordable energy from rice straw than ever before.
Creating biomass energy from rice waste
The process involves a biomass conversion technology called pyrolysis, which involves heating organic waste materials to around 500 °C to break them down and produce vapour and solid products. Pyrolysis oil can be created by condensing some of the vapour into a liquid product. Both pyrolysis vapour and liquid bio-oil can be converted to electricity.
However, only 35% of the thermal energy of rice straw is converted to affordable electricity via current methods. But this is set to change, as consortium member Carnot Limited, has patented their combustion engine design that could see this figure double to 70%.
Biomass energy is advantageous as it could assist low- and middle-income countries in creating their own locally generated energy, producing new job opportunities. With the global transition to net zero taking shape, using biomass for energy generation could also help contribute to net zero by 2050.
About the project
Initially, the project will focus on developing a business model that helps companies and local authorities on Indonesia’s Lombok Island to generate local, affordable energy. This will expand to other countries with a biomass capacity.
Dr Jude Onwudili, based at Aston University’s Energy and Bioproducts Research Institute, said: “This project has huge potential – commercialisation of this combined technology will have significant economic benefits for the people of Indonesia through direct and indirect job creation, including the feedstock supply chain and electricity distribution and sales.
“About one million Indonesian homes lack access to energy and Indonesia’s 6,000 inhabited islands make sustainable infrastructure development challenging in areas such as Lombok Island.
“The new techniques being explored could reduce environmental pollution, contribute to net zero, and most importantly, provide access to affordable energy from sustainable local agricultural waste.
“Aston University is a global leader in bioenergy and energy systems, and I am delighted we received funding to explore this area.”
The project team has calculated that over a power plant’s life, biomass produces cheaper electricity (approx. $4.3/kWh), compared to solar (approx. $6.6/kWh), geothermal (approx. $6.9/kWh), coal (approx. $7.1/kWh), wind (approx. $8/kWh), and subsidised gas (approx. $8.4/kWh).
The project is set to start in April 2023 with a total of £1.5m in funding for the four partners from Innovate UK.
As well as Carnot Limited, the Aston University team will also work with two other UK-based businesses to deliver the project – PyroGenesys and Straw Innovations.
PyroGenesys specialises in PyroChemy technology which will convert 70% of the rice straw into vapour or bio-oil for electricity production. The remainder will be converted into nutrient-rich biochar, which can be sold back for use as fertiliser on the rice farms.
Straw Innovations will contribute its rice straw harvesting and collection expertise, with its many years of similar operations in Asia.
