Done right, UK-sourced biomass can help wildlife and provide energy

Woodland wildlife under threat

The RSPB’s woodland nature reserves are some of the organisation’s most enchanted places up and down the UK. As a young boy a trip to Nagshead in Gloucestershire to search for pied flycatchers and redstarts was always a school holiday treat.

At this time of year woodlands are thrumming with birdsong and butterflies darting about. A few nights ago I went to a woodland in Cambridgeshire and saw silver-washed fritillary butterflies performing courtship flights along the woodland rides. In a few short months woodlands’ beauty will be found by looking down, not up: their floors look like large-scale Jackson Pollock paintings, as the trees spill their multicoloured leaves onto the ground. In fact it’s worth checking out Pollock’s Autumn Rhythm and seeing whether you think it compares to the real thing.

But perhaps not a lot of people know that the picture for our woodland wildlife isn’t looking very rosy. Birds like the willow tit, a woodland specialist, have declined by over 80%, making it our fastest declining resident bird. The State of Nature report showed that of the 1256 woodland species we have data for, 60% have declined over the past 50 years, 35% strongly. Some of our woodland birds migrate, so the problems might lie elsewhere, but equally we know that some of the causes of these declines are right here, in UK woodlands.

Many of our woods have fallen into neglect – the kind of management that keeps them healthy has stopped and they have become less and less suitable for wildlife.

Using wood wisely to help wildlife and the climate

But our woodlands could be wildlife havens again, as well as providing an important natural resource.

We believe that the UK’s woodlands can provide a valuable resource for a range of industries. By being sensitively managed for their useful resources the woodlands could also be made more hospitable to wildlife once more.

Wood from our woodlands could provide an important resource for industries like construction and furniture, where the carbon stored in the wood stays locked up for decades, helping the climate.

Wherever possible, wood should be used in this way, then reused, recycled, and finally, used for energy.

But the UK Government is incentivising the combustion of virgin wood for energy in power stations that produce electricity. Subsidies are available to new dedicated biomass power stations that burn wood, or to coal power stations that convert to burning wood.

This means that virgin wood that could otherwise lock carbon up in furniture or construction could end up being burned. Government predict that by 2017 the UK could be burning six times the UK forest harvest, putting extra pressure on UK forests as well as requiring vast quantities of imported wood.

This could see wood going straight from the forest to the power station. It will also mean that large amounts of wood pellets are going to be imported from North America. Again, Government’s own analysis shows that in many cases burning wood straight from the forest in this way, allowing the carbon to escape into the atmosphere, can, in the short term, be worse for climate change than coal!

Because the Government has not put stringent enough sustainability criteria in place either, this means that North American forests and their wildlife are under severe threat from burgeoning demand for wood for electricity. In fact, only 70% of wood that’s burned has to be sustainable for a company to receive subsidies. This could be a disaster for wildlife overseas.

In addition, large-scale power stations that produce electricity are very inefficient. Drax, a coal power station in the North of England, has already converted one of its units to biomass and plans to convert others. In 2013 Drax imported burned 3.5 million tonnes of biomass and expects to burn 4.5 million tonnes in 2014, with only 150,000 tonnes coming from within the UK[1]. The rest is imported.

Instead, the RSPB would like to see Government designing a policy framework that supports a very different kind of bioenergy industry: one that’s based primarily on efficient combined heat and power technologies and on sustainable feedstocks such as residues, wastes and some woody energy crops.

In some cases a limited supply of wood from local woodfuel markets could support woodland management for wildlife. Although wherever possible the wood burned should be at the end of its life, having been used by other industries first. And where this isn’t possible because the wood isn’t of high enough quality it must at the very least be from woodlands that meet sustainability requirements under the UK Forest Standard and burned in the most efficient way possible.

In this way, many more UK woodlands could be brought back into management, transforming them once more into homes for our rare and wonderful woodland wildlife.

Beyond the woods

The RSPB has also been working to explore the possibilities of generating biomass from some of its other kinds of reserves.

Being more resourceful about how we utilise materials from the management of our nature reserves could make a significant contribution to reducing our reliance on fossil fuels and help to provide more sustainable ways through which to provide us with our heat and power.

After the RSPB conducted a few experimental trials turning rush and reed into briquettes that can be burned, the UK Government Department of Energy and Climate Change (DECC) recognised this as an opportunity and seized the initiative by funding the Wetland Biomass to Bioenergy Project. With the potential to utilise existing material, which would enhance areas for biodiversity, and not impact on food production, the idea had huge potential. The project looked to develop the end-to-end processes necessary to remove biomass from an ecological site and turn it into marketable bioenergy products (e.g. briquettes or bio-methane via anaerobic digestion). Set up as a competition, DECC aimed to encourage consortiums of small business, academia and specialists to work together to find a solution.

Starting with 14 applications, seven of which were developed through to feasibility stage, three consortiums of participants made it through to the conclusion, during which time their end-to-end processes were trialled on our own RSPB nature reserves and those or partners.

Each of the three successful consortiums took a different approach to design an end-to-end solution. AB Systems developed specialist tracked harvesters with cut and collection systems, utilised innovative AgBag storage options and a mobile briquetting system. Natural Synergies developed a bespoke medium scale anaerobic digestion unit with specific adaptations for coping with challenging wetland biomass. AMW-IBERS utilised a number of different technologies, including anaerobic digestion, pyrolysis and mobile briquetting, their process separated the biomass into a solid and liquid fraction for conversion. The three projects were conducted across the UK; in Somerset, East of England and Northern Scotland.  As a result we know have a portfolio of techniques that can be utilised for the conversion of wetland biomass..

This means that otherwise under utilised material generated during the management of RSPB nature reserves can now be used to generate heat and electricity.

The DECC project enabled the completion of trials and analysis of different biomass types which used different conversion processes. These projects have provided the crucial foundations for future decision making around building sustainable biomass to energy schemes.