Biomass is only sustainable and renewable when sourced from responsibly managed forests that are growing, not from old growth, primary forest or protected biodiverse areas. And this should be independently verified, writes Dr Rebecca Heaton.

Dr Rebecca Heaton is a forester by training and Head of Sustainability and Policy at Drax Power. She is responsible for the sustainability of the global forest supply chains used to deliver sustainable biomass to its power station.

Healthy wood markets encourage responsible forest management, which leads to better quality trees and more carbon stored in the forest and in solid wood products. It is this principle that underpins the world’s oldest and one of Europe’s most widespread forms of renewable energy, woody biomass from forests.

Sustainable biomass, including forest biomass, accounts for as much as 45% of all renewables consumed in the EU – considerably more than wind, geothermal, hydro and solar put together. It is used for both heat and power across Europe, heating people’s homes directly or through district heating, and providing power to businesses and homes.

It can, for example in the UK, Denmark, Belgium and the Netherlands, also serve as a direct replacement for electricity generation from fossil fuels such as coal. This means that as well as helping to increase the share of renewables, it also directly removes millions of tonnes of CO2 from the power grid. What is more, its dispatchability can balance the grid to allow other intermittent renewables such as solar and wind to flourish until the time eventually comes when they can stand alone.

But biomass is only sustainable and renewable when certain key conditions are met – such as being sourced from responsibly managed forests that are growing and not being from high risk feedstocks like old growth and primary forest or protected biodiverse areas. And this should be independently verified.

Biomass pellet demand in the EU, used for heating and for power, is now over 20 million tonnes, 40% of which is imported (mainly from the US). Pellet demand is forecast to increase to around 48 million tonnes per annum in the next 5 years, which can provide a valuable market for low grade wood and encourage good forest management.

This is what has happened in the US, where although harvesting increased by 57% over the last 60 years, investment in sustainable forest management has led to a 112% increase in forest growth over the same period. Because of healthy markets for wood products like pellets, the area of forest in the US remained largely the same but the amount of stored carbon in the standing trees increased by 108% over this period.

These statistics are important, because they show that the higher the growth rate the more carbon is sequestered. Vigorously growing young stands in working forests absorb more carbon than is absorbed in over-mature stands of trees, particularly when there is no active management. Increased production of high value saw-timber also helps to store more carbon in solid wood products, for example building construction and furniture.

Once forests have reached maturity the rate of carbon sequestering drops off dramatically. Carbon remains stored in the standing trees but the forest no longer absorbs as much carbon from the atmosphere. Therefore, a continual cycle of harvesting and re-planting with young stands, along with storage in solid wood products, offers the optimum carbon sequestration model. Biomass can contribute to this process by providing a market for the low grade wood left over as a bi-product of this process. Landowners are increasingly taking a long-term view, seeing the profits in sustainable forestry rather than, for example, converting that land into real-estate and urban development.

Biomass is of course only a small part of the financial well-being of a forest. It’s paying power is considerably lower than that of other industries such as saw-timber for construction and furniture – meaning that forests are almost never felled for just biomass. But biomass nevertheless fits into the picture, as it uses the fibre that the others don’t. Thinnings, for example, are wood fibre that needs to be removed anyway in order to achieve taller, stronger and more valuable trees for lumber. Around 50% of the wood fibre going into a sawmill ends up as residues in the form of wood chips and sawdust, and sometimes without a local market. Biomass markets for this type of fibre can make the difference between a viable and a loss making forest.

Furthermore, there are still substantial quantities of by-products of the forestry industry that go unused in many parts of the world, in particular the Baltic states, South-Eastern US and Canada. It is logical that biomass is sourced from regions where the largest surpluses exist and the forest carbon balance can be maintained. These newer markets help reduce the pressure on established markets thus keeping prices down and enabling more wood to be used for long term carbon storage, such as furniture and construction.

If managed sustainably, biomass is a major part of the energy solution in Europe. This is why is it is so important for the European Parliament’s ENVI Committee to support the role of woody biomass and adopt effective sustainability criteria.

Whether produced in the EU or imported, without sustainable woody biomass, the EU will never be able to reach the Commission’s proposed renewable energy target of 27%, let alone the 40% that many are calling for.