A question of sustainability

The Supergen Bioenergy Hub recently collaborated with the Carbon Recycling Network, the Biomass Biorefinery Network, and the High Value Biorenewables Network (three of the Biotechnology and Biological Sciences Research Council Networks in Industrial Biotechnology and Bioenergy (BBSRC NIBB)) to submit a joint response to a Department for Business Energy and Industrial Strategy (BEIS) Call for Evidence on The Role of Biomass in Achieving Net Zero.

The responses to the Call for Evidence will inform the development of the new UK biomass strategy, which is due to be published in 2022. This is the third in our ‘Biomass for net zero?’ blog series exploring some of the key points from our evidence submission. As we get closer to COP26, the series will also highlight some of the challenges that need to be addressed in order to realise the potential of biomass systems to support the transition to net zero.

Authored by Patricia Thornley, Supergen Bioenergy Hub

Sustainable is a word we hear a lot nowadays. Politicians tell us they are looking for sustainable solutions, scientists claim to be developing sustainable visions of the future, non-governmental organisations criticise the lack of sustainability, and every large company seems to have someone focused on corporate or social sustainability. So what does sustainability actually mean? And are the various initiatives as sustainable as they could be, or is all that glitters not quite as green as it looks?

Sustainability is a deceptively simple concept: to provide for our own needs while not impacting on the ability of future generations to provide for theirs. But defining what is needed to make that happen is actually much harder than it looks. We live on a finite earth: one planet with a certain amount of resources (land, ocean, minerals, etc). There is no (proven) way to go beyond our planetary boundary and so these limited resources have to support our livelihoods, and that of our children, and our children’s children, etc. That open-ended, forward-looking metric is not one with which we are used to dealing. Environmental regulations often focus on rates of flow (such as limiting emissions from a power plant, levels of discharge from a fish farm, or disposal of waste to land). But that doesn’t really capture the essence of sustainability; it is more about the extent to which our natural resources are depleted. When thinking sustainably we need to think about the overall available reserves, not the rates of flow that are much easier to measure and control. Whether it is the remaining quantity of rare earth metals we can access for manufacturing batteries, or the atmosphere that can only accept a certain amount of greenhouse gases, the important thing is not the rate at which we deplete or pollute but the net state of our planetary assets.

Although we often think of this as an ‘environmental’ issue, sustainability is actually a much broader concept than that. It is about our environment (the carefully balanced ecosystem on which we depend) but we live in a global society that is interconnected in many ways and so sustainability also has a social dimension (which incorporates education, employment and health) as well as an economic one. Most human behaviour and transactions are mediated by financial mechanisms and so we cannot ignore the fiscal structures we have established, which means that sustainable development must also be economically sustainable. Achieving this may well require policy interventions or subsidies to correct existing economic frameworks that fail to value the environmental impacts.

As soon as we introduce more than one objective things become complicated because we now have a multi-variable, non-linear problem. For example, changing a system to maximise greenhouse gas reductions may result in increased ocean acidification or soil carbon depletion. It is therefore imperative that sustainability assessments take a holistic approach that recognises the multiple impacts of energy and production systems and their associated trade-offs. Put simply, you can’t have your cake and eat it. If you engineer a system change that improves one thing (such as greenhouse gas emissions) it is almost inevitable that other things will have changed as well, and so it is important that sustainability assessments and regulatory frameworks are flexible enough to take account of these trade-offs, recognising the dynamic costs and benefits across multiple indicators.

One of the things that therefore annoys me most when it comes to sustainability is being asked: “Is that sustainable?” My answer is almost invariably: “It depends.” It depends on your objective, your perspective and what you deem to be acceptable limits. Legislation often paints a picture of qualifying and non-qualifying systems, implying that one is sustainable and the other not. In reality there is no hard and fast cut-off point. There may be tipping points within the global environmental system, but that doesn’t automatically translate back to a convenient limit we can set to ensure that we remain ‘sustainable’. In other words, sustainability is not black and white, but shades of grey. It is almost always possible to be more sustainable against a particular metric, but bear in mind that by so doing you may make other things worse. The ideal would be to maximise our performance against a range of environmental, social and economic indicators – but even the relative importance of these is subjective.

So I feel the best solution we have is to set frameworks that focus on the key metrics that are most significant for our identified needs, but monitor others as well. Then we should reward performance on a continuum that encourages continuous improvement. We need to move away from setting minimum performance levels and arbitrary thresholds, which simply risk a dash to mediocrity. Above all I think we need transparency around these reporting systems, where fiscal rewards for sustainable energy solutions are set to encourage maximum greenhouse gas reductions, while also monitoring and recording other impacts.

Nowhere is this need more evident than for bioenergy systems. The wood pellets that power our homes could have been harvested unsustainably in countries with weak governance and monitoring regimes, or be well-documented and evidenced in accordance with carefully monitored harvesting standards. The fuel in our tank may have originated from harmful wastes that would otherwise be discharged to sewers, or may have incurred land-use change and biodiversity impacts in ecologically sensitive regions of the world. The gas we burn could have been produced sustainably from agricultural residues, or may be the result of land/farm consolidation and lost livelihoods. It is impossible to determine the sustainability from the product itself and so there is a huge need for transparency to build trust and confidence in technologies that have the potential to deliver so many sustainable environmental benefits.

Please send queries to Dr Joanna Sparks, Biomass Policy Fellow via j.sparks@aston.ac.uk.