University study concludes ‘huge and profitable’ potential for biogas
Sweden’s Linköping University revealed a study into the food industry, outlining its high efficiency regarding energy consumption and its use of primary raw materials.
However, the release argues that research has not examined how waste in the form of organic by-products can be used in the most efficient way.
“Much of the waste is used as animal fodder, and some goes to compost or combustion”, says Emma Lindkvist, doctoral student in the Division of Energy Systems, also working at the Swedish Biogas Research Center (BRC) at Linköping University.
Published in the academic journal Energies, Lindkvist alongside BRC researchers Jenny Ivner and Magnus Karlsson examined the food industry to investigate the way in which the organic by-products can create the greatest benefit – for the economy, the environment and energy conservation.
The researchers selected five regions, contacting all major food producers in each respective region. Each region had a specific characteristic, whereby one, for example, was home to a large fishing industry whilst another was close to a big city. This ensured as wide of a perspective as possible.
“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,” said Lindkvist.
“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.”
Continuing without change in any region was usually the worst alternative, according to the study, from both environmental and energy-efficiency perspectives. A few cases in which other energy was derived from wind power were exceptions.
If a coal-condensing system was used in the food producer’s system, biogas produced for electricity and heat production held an advantage over biogas-derived vehicle fuel, since the calculations used were based on the assumption that the biogas is upgraded using electricity produced from coal-fired power stations.
However, biogas used as vehicle fuel is the most advantageous when the upgrade is carried out using electricity from wind power.
“I was surprised to see that the different systems differed, and we plan to construct a model in the next step that will enable us to optimise the systems,” said Lindkvist.
“We want to be able to follow individual streams of material. It’s possible that high-value waste should continue to be used as animal fodder: remember that animals need to get food from somewhere.”
Concluding, the researchers found that, in terms of conservation of energy and care for the environment, it would be beneficial if the food industry wasn’t the only stakeholder involved when decisions are being made regarding the organic by-products.
Instead, collaboration between industries, particularly the energy and public sectors is desirable as there is a ‘huge and profitable’ potential for the use of biogas both for the environment and the economy.
You can access the study here.