Does your business produce or use bio-based products? Generating energy from residues could be an option worth exploring, as Dr Oisín de Priall discusses in his blog.
In light of recent global events, the volatility of fossil fuel-driven energy markets has yet again been exposed, putting pressure on businesses and their ability to function profitably, especially where energy bills are concerned.
However, there are other potential ways to generate energy that don’t rely on market forces by looking at solutions closer to home - in particular, organic residues that enter waste streams as a byproduct of business operations and redirecting these losses back into energy. This approach can potentially have two immediate impacts, firstly by protecting businesses from an over reliance on fossil fuels, and secondly by providing a smarter, more environmentally friendly way to generate energy, such as heat, and circulating it back into operations.
This is an approach that is backed by research conducted by the IEA Bioenergy Technology Collaboration Programme, which estimated in its Bioenergy Review 2023 that up to 50% of bioenergy demand could be met by biomass residues by 2050. The research points to the fact that bio residues remain a largely untapped energy resource, further highlighted by Bioenergy Europe in their most recent publication on the topic. They estimate that 146,000 kt/year of dry agricultural residues could be sustainably collected annually. This could produce 55Mtoe of energy from agricultural residues per year or approximately 640 TWh. It’s clear, then, that capturing as much of this residue as possible is vital for the push towards a more sustainable future.
Looking closer to home for our energy
With energy prices currently going through incredible fluctuations, average prices are significantly higher than they have been over the last decade. This has had negative impacts across all aspects of domestic and non-domestic life, with higher operating costs leading to higher consumers costs for goods and services. These costs need to be managed to reduce the impacts of increased costs being consistently pushed onto the end consumer, and to ensure business viability.
Energy costs are difficult to manage when the source of fuel is from an external supplier, particularly fossil fuels, which are typically imported over long distances. Fluctuations in supply availability, geopolitical instability and transport costs all impact on the price per litre or kWh that industry and consumers will pay. Minimising the amount of fuels that we import is critical if we are to isolate ourselves from these price increases and instability.
One approach to gaining certainty over energy input costs is through utilising resources that are closer to home to generate our energy. For industrial heating and process steam we can achieve this by using waste resources generated from an existing process as the fuel for our energy demands. This approach is referred to as the valorisation of a waste stream, and in some circumstances is an exemplar of the ‘circular economy’, where additional value and use is extracted from a material before final disposal.
Businesses which generate biogenic wastes such as agricultural waste, food residues and green waste or byproducts are particularly well positioned, and could all be using their own waste as an energy source, cutting down on both energy costs and waste disposal fees. Disposing of waste streams can be expensive with gate fees and transport, managing your own waste on site can have multiple benefits. An example could be oat husks from cereal production used for heating in the food production process or spent coffee grounds from the instant coffee factories being used to power their process.
Environmental benefits and driving supply chain value from residues
Current common methods to dispose of these materials are to spread them on land to return nutrients to the soil, although this can be expensive and is governed by strict permitting. Increased regulation has seen this become a less attractive method, with the negative impact on water quality one of the driving factors. Saturation of arable land with excess nutrients will lead to nutrient run off, effecting local waterways. This can lead to poor water quality over time, and eutrophication if not managed properly. Eutrophication is mainly caused by excessive nitrogen and phosphorus in the water, leading to oxygen depletion harming life in the water. An example of this happening in real time is in Lough Neagh in Northern Ireland, the UK’s largest freshwater lake.
Diverting material such as digestates, slurries and agri-residues from land spreading is therefore critical to minimise environmental detriment and maximise resource efficiency. Through partnering producers of these materials with end users who can benefit from them, we can improve energy security, optimise existing supply chains and add value to material previously thought of as a waste. Further benefits are the energy carbon savings available to the end user, and the push towards Net Zero emissions and emphasis on the climate means that this cannot be understated.
Is bioenergy from residues right for your business?
The principals behind bioenergy from residues are both logical and achievable but knowing where or how to start this process can be challenging. Reheat has significant experience and expertise in this field and our consultancy team can support your business if you generate an organic based by product or are interested in using another processes’ residue for your own energy needs.
Simply get in touch with us to discuss how we can work with you to maximise your process efficiency, minimise unnecessary costs and reduce your carbon footprint.
