Bioenergy and Sustainability

Can biomass fuel really help with climate change?

Biomass fuel and humans go back a long way – all the way back to the first fires humans built with wood over 200,000 years ago. For a while, our relationship blossomed but then we fell in love with fossil fuels. That relationship brought us to where we are today but the time has come to move on. Fossil fuel use has wrapped the Earth in a blanket of greenhouse gases that is causing the Earth’s temperatures to rise. The benefits of fossil-fuel use are now outweighed by the destruction caused by more frequent storms, floods and droughts that are the symptoms of a changing climate. But is rekindling our first love really a good idea? Can rekindling our first love really help halt climate change?   

The answer is YES…but….

Yes, bioenergy is considered carbon neutral and yes, it is one of the few sources of renewable energy for sectors such as aviation and heavy industry but inappropriate use can actually result in more greenhouse gas emissions than are caused by fossil-fuels. If it is to genuinely help slow climate change then biomass fuel must be used responsibly.

As most 10-year-olds know, trees and plants are the lungs of the earth. They take in carbon dioxide and release oxygen. When biomass fuel is used to produce energy, the carbon dioxide stored in the trees or plants is released back into the atmosphere. This is what allows biomass fuel to be considered carbon-neutral. This however is not the whole story.

Emissions can also be released in other ways

Growing, harvesting, transporting, refining and burning biomass fuel can all add additional emissions. For example, the fertiliser used to accelerate plant growth releases emissions with very high global warming potential. Likewise, refining raw biomass into usable fuel requires energy, not all of which is renewable. When taken together, these supply chain activities can take back some or, in the worst cases, all the climate benefit. The inappropriate use of land and of forest material also have negative social and economic consequences. For example, converting land that currently produces food to energy crops may result in some regions having to rely more heavily on food imports and leave them more exposed to fluctuations in international food prices. Taken together, environmental, economic and social factors define the sustainability of a biomass fuel supply chain.

So what can we do to improve supply chain sustainability, some clear actions include:

1. We should only use those parts of a tree that are unsuitable for timber products for energy. Everyday products such as tables, chairs and doors made from timber lock the carbon away for much longer.
2. This residual material should only come from forests that are replanted and from trees that have matured fully or that are harvested the forest as part of good forest management.
3. Crops should only be planted on suitable land. Policy makers must take care to ensure that changing the use of land to produce biomass fuel does have adverse impacts elsewhere – such as the nightmare scenario where a rainforest is cleared to make way for crops.
4. The technology that uses biomass fuel should be as efficient as possible, so less fuel is required to produce the same amount of energy.
5. Longer term, biomass fuel should be used with carbon capture and storage technology.

What are we doing to ensure the right biomass fuels are used?

There is growing momentum around the world to govern the sustainability of biomass fuels.  Governments and industry have taken on the challenge of ensuring the sustainability of biomass fuels we use. For countries like Ireland, where the impact of supply chain and land use emissions are counted towards greenhouse gas reduction targets, the question of sustainability goes beyond just good practice and has a direct impact on our efforts to meet binding greenhouse gas emissions targets. From 2021 EU legislation will require biomass users to meet sustainability criteria that aims to ensure that bioenergy reduces total greenhouse gas emissions by at least 70% as compared to fossil-fuel options. It also includes requirements to demonstrate good forest management and land use practices. Existing Irish legislation already covers these requirements well. But more is required to allow bioenergy users demonstrate compliance with the greenhouse gas emission standard.

Most Irish suppliers have little to fear of sustainability schemes which can level the playing field with imports from outside the EU. Most of the bioenergy that comes though Irish supply chains have low supply chain related emissions.

For Irish supply chains that are less sustainable right now, biomass growers and suppliers can make changes to improve the sustainability performance of their biomass fuels. Take for example grass silage which has significant biogas production potential. Reducing the amount of artificial fertiliser used and changing the type of grass grown can improve that crop’s sustainability performance and increase the amount of grass that is suitable for energy production.

Future for Bioenergy

My primary school teacher was fond of recounting how Sir Walter Raleigh had pillaged the ancient Irish woods for the British Navy and to re-build London after the great fire in 1666. Construction and ship building were undoubtedly important at the time, as the mitigation of climate change is now. But my teacher certainly did not consider it a sustainable use of Ireland’s resources because of the social, economic and environmental impacts this had. Perhaps there is a lesson for us all -  make sure that we do all that we can do to use our biomass resources sustainably and avoid being remembered as Mr. Raleigh was by my teacher. 

Overall Ireland is in good shape to supply sustainable biomass to the energy sector. But good governance is essential if we don’t want future generations to look back and wonder about what might have been.

Getting back together with your first love has its complications. In the case of biomass fuel, clear ground rules are needed to help a sustainable long-term relationship to flourish. The good news is that we are already well placed to deliver sustainable biomass fuel in Ireland, but new governance schemes are needed to maintain this.

How you can do your bit

• If you are using wood fuel, make sure that it comes from a certified source. The Wood Fuel Quality Association certifies wood fuel quality in Ireland.
• If possible, look to source certified fuel that comes from a biomass resource close to you.
• Look to see what measures your business can take to improve the efficiency of your building. Less fuel will be required to keep you warm. SEAI grant schemes can help you with this.
• At home, never try to burn damp wood or wood that was previously used in furniture, buildings or for other purposes such as wood pallets. This can release dangerous particles into the air you and your neighbours breathe.
• Separate your food waste into brown bins – this makes it much more accessible for use in anaerobic digesters used to produce biogas.