Making biogas from food waste pays, economically and environmentally
Huge gains can be made by using waste from the food industry for biogas production, no matter whether the biogas is used in vehicles or to produce electricity and heat.
That is the conclusion of an in-depth study of the food industry in Sweden by researchers from the Biogas Research Centre, who examined how waste in the form of organic by-products can be used in the most efficient way.
Emma Lindkvist, doctoral student in the Division of Energy Systems, who also works at the Swedish Biogas Research Centre, BRC, at Linköping University, set out to investigate the way in which the organic by-products from food manufacturing can create the greatest benefit – for the economy, the environment and energy conservation.
Biogas is the ‘better alternative’
Lindkvist and her co-authors, Magnus Karlsson and Jenny Avner, studied five different types of food manufacture in Sweden; the country’s fourth largest industry in terms of employment and second largest in revenue terms.
“We then analysed three scenarios: to continue as before, to produce biogas upgraded to vehicle fuel, and to produce biogas for electricity and heat production. And we looked at economic, environmental and energy profitability”, says Emma Lindkvist.
They also analysed a scenario in which the system contains significant amounts of wind power, and another in which the electricity and heat produced from biogas replaces that produced from coal.
“In all three perspectives, biogas is the better alternative. In four of the five cases, biogas that has been upgraded to vehicle fuel gives the highest economic gains. In the fifth case, biogas was profitable, but continuing to use the previous system was significantly more profitable. This is because the biogas potential in the waste is lower here than in the other cases.”
Biogas is ‘profitable’
Continuing with business as usual was usually the poorest alternative from both environmental and energy-efficiency perspectives. A few cases in which other energy was derived from wind power were exceptions.
The conclusion drawn by the researchers is that in terms of care for the environment and conservation of energy, it would be an advantage if the food industry was not the only stakeholder involved when decisions are made about how organic by-products are to be dealt with.
Collaboration between the industries, the energy sector and the public sector is desirable, since there is a huge and profitable potential for the use of biogas, profitable not only for the environment and for the energy sector, but also, and not least, for the economy.
System Analysis of Biogas Production—Part II, Application in Food Industry Systems, Emma Lindkvist, Magnus Karlsson and Jenny Ivner, Energies 2019, DOI:10.3390/en12030412