WHY BIOMASS ELECTRICITY SHOULD NOT RECEIVE RENEWABLE ENERGY SUBSIDIES
In 2015, 9% of the UK’s electricty was generated by biomass electricity1. This counts towards our renewable energy targets, and is viewed by many as a clean, green source of electricity.
However, Biofuelwatch, other environmental NGOs and leading scientists disagree; far from helping to reduce carbon emissions and making our energy system more sustainable, biomass electricity causes climate impacts which are commonly no better than those from coal burning, along with increased forest degradation and biodiversity losses.
Yet biomass electricity receives strong support from the UK government. Last year, energy companies received £817 million in UK subsidies for burning solid biomass for electricity, the vast majority of it wood2. This figure is expected to increase substantially in future, given increases in capacity and a higher subsidy rate being guaranteed by the Contracts for Difference awarded to new biomass schemes.
As a result of those subsidies, UK power stations burned pellets and woodchips made from almost 15 million tonnes of green wood for electricity in 2014/153. By comparison, the UK’s total wood production in 2015 was just 10.8 million tonnes. The UK is now the world’s number one importer of pellets, most of them from North America.
The UK’s demand for wood is growing as more biomass power plants are approved and subsidised, and is expected to be as high as 23 million tonnes annually in the next few years4.
We are strongly opposed to subsidies for biomass electricity, and believe instead that the subsidy system should be reformed so that genuinely low-carbon renewable energy, such as wind, solar and tidal, and energy demand reduction is properly supported, rather than undermined as it has been recently.
Read on to find out more
Climate impacts of biomass electricity
At the power station smokestack, burning biomass for electricity always produces more CO2 emissions than burning coal (per unit of electricity generated). This is because electricity generation from biomass is far less efficient than that from coal. This is widely acknowledged, for example by the International Panel on Climate Change5.
The CO2 emissions from burning biomass are currently ignored by operators and the Government alike, on the assumption that future tree growth will sequester the emitted CO2. However, a growing volume of scientific studies shows this assumption to be flawed6.
This is due to:
- the time lag between CO2emissions from power stations on the one hand and CO2sequestration by future tree growth;
- indirect impacts, including the use of waste and residues for bioenergy resulting in other industries relying on more extensive or intensive logging;
- long-term reductions in soil and vegetation carbon stocks due to of more extensive or intensive logging as well as the conversion of natural forests to monoculture plantations.
The climate impacts of biomass electricity are even worse when the substantial methane emissions from woodchip storage are taken into account.
Although the climate impacts of biomass sourced through additional logging are the worst, scientific evidence shows that burning forest residues for electricity nonetheless results in significantly adverse climate impacts over a period of several decades7.
In summary, burning biomass produces a “carbon debt” exactly at the time when globally we urgently need to be reducing carbon emissions – we must cut global CO2 emissions at ~8% year on year to have a reasonable (66%) chance of staying below the 2°C threshold of ‘dangerous’ climate change8.
We cannot put off meaningful emissions reductions any further. Instead of further logging forests and replacing them with monoculture plantations, this is the exact time we must conserve and expand them.
Impacts on forests and biodiversity
As well as being essential ‘carbon sinks’, soaking up large volumes of CO2 that humanity emits every year, forests are also unique ecosystems, home to thousands of species.
There is strong evidence that biomass electricity in the UK is causing destruction and degradation of forests.
Most biomass in the UK is burnt in the form of wood pellets. The South-East US is a large and rapidly growing centre of wood pellet production and export; exports rose from 1.6 million tonnes in 20129 to 6.1 million tonnes in 201510, and demand is only set to grow as plans for expansion are underway.
Studies from NGOs and in peer-reviewed scientific journals show that the logging of forests and conversion to monoculture plantations due to the growing wood pellet demand poses a serious threat to the old-growth wetland forests of the South-East. These forests are found within a ‘biodiversity hotspot’, and contain large numbers of rare and endangered species, including black bears, numerous songbird species, bats and butterflies. They also provide essential ecosystem services, such as purifying water and flood control.
Most of this wood pellet production is for export to the UK. The largest customer is Drax Power Station in Yorkshire, the largest biomass power plant in the world, which in 2015 received £470 million in government subsidy.
According to Drax Plc’s Annual Report for 2015, the power station burnt over 3.1 million tonnes of pellets from the US that year. As each tonne of pellets requires two tonnes of green wood, Drax burnt the equivalent of over 6.2 million tonnes of wood from the US. All of this came from pellet mills in the southern US, the majority from pellet mills owned by Enviva. US conservation NGO investigations11 have shown logs from clearcut wetland forests in North Carolina being processed at an Enviva pellet mill known to supply Drax (see picture above).
Processing residues and waste wood are often cited as potential bioenergy sources with no negative biodiversity impacts. However, figures contained in a US Department of Agriculture Report from 201212 show that 59.3 million dry tonnes of wood residues arose at timber-processing facilities in the US, but less than 1% of those were not used for other purposes and thus available for pellet production. Clearly the availability of processing residues and waste wood for bioenergy is too small to support large-scale biomass electricity.
Furthermore, most biomass power stations, including all current and future UK projects, cannot burn residues for technical reasons; they have a high bark content, which can cause corrosion of boilers13. Drax’s technical report confirms this is the case.
The Convention on Biological Diversity and its Aichi Target require all member states (including the UK) to reduce or phase out subsidies that are harmful to biodiversity. There is strong evidence that UK subsidies are contravening these targets with subsidies for biomass electricity.
Biomass impacts on air quality
Additionally, biomass electricity has a negative impact on air quality and peoples’ health.
Biomass power stations emit large quantities of nitrogen oxides (NOx), sulphur dioxide (SO2), carbon monoxide (CO) and small particulates (PM10, including PM2.5), as well as a range of other pollutants. In fact, biomass plants emit a similar range and volume of pollutants to coal power stations, albeit more of some pollutants and less of others; more Volatile Organic Compounds and small particulates, but less sulphur dioxide and mercury.
The effects of air pollution on health are well accepted and documented14. Air pollution is estimated to cause 40,000 deaths in the UK every year15, from heart attacks and strokes, cancer and lung and respiratory diseases.
The World Health Organisation has collated detailed evidence on the effects of air pollution on health16. The pollutants from biomass power stations are linked to a range of health conditions, from childhood asthma and bronchitis, to lung disease, cardiovascular disease, cancer and developmental problems.
Biomass power plants emit high levels of ultrafine particles PM2.517. This is especially worrying as these particulates cross the lung-blood barrier, meaning there is no safe level of exposure. Dioxins and Furans, highly toxic and persistant pollutants are emitted from wood with high concentrations of heavy metals; this is very common when treated waste wood is burnt, but still occurs with virgin untreated wood.
For instance, in 2012 a single 34MW biomass power station in Scotland emitted 359.05 tonnes of NOx and 2.307 tonnes of small particulates (PM10 and below). This is equivalent to NOx emissions from adding 853,700 diesel cars to the road, and PM10 emissions from adding 2,000 diesel cars to the road18.
Can sustainability standards result in ‘good biomass’?
In 2015, the UK Government published new sustainability standards for biomass electricity. Many environmental groups, including Biofuelwatch roundly rejected these standards as insufficient and not based on science.
The UK Government’s sustainability standards are deeply flawed. The current greenhouse gas criteria states that biomass electricity may qualify for Renewables Obligation (RO) support if it has a carbon intensity of 200 kg CO2e/MWh or less.
Firstly, this is far higher than other renewable sources (e.g. wind, 4-31 kg CO2e/MWh). Secondly, the method used to estimate the carbon intensity only includes emissions from the harvesting, processing and transport of the wood but ignores all other sources of emissions (as listed in the first section); from total changes to the structure of the forest, to the forgone sequestration (the CO2 the forest could have absorbed if left untouched) to the indirect impacts on other areas of land.
This results in classifying sources of biomass which actually have emissions intensities in excess of 200 kg CO2e/MWh, and even those with intensities in excess of coal, as being ‘low carbon’ and eligible for subsidies.19
The land criteria for biomass are even weaker than the greenhouse-gas criteria. Only 70% of the wood burnt by a power plant must be classed as ‘sustainable’ in order to qualify for subsidies. The ‘sustainable’ criteria themselves are vague and based on principles rather than measurable standards – for instance, ‘protecting water, soil and biodiversity’ and ‘conserving key ecosystems’. Furthermore, wood pellet providers are permitted to provide their own evidence of compliance with these standards – external verification and auditing is not required.
However, no sustainability standards will overcome the fundamental problem with biomass: the demand for burning wood is simply too high. There is a miniscule volume of waste wood that could be burnt and represent a true emissions saving and not damage biodiversity compared to the current demand for biomass for electricity. It is simply not possible to replace a significant portion of fossil fuel burning with biomass burning. UK policy should reflect this by not subsidising biomass and setting stringent caps on the total biomass capacity in the country.
Alternatives to Biomass Electricity
A recent report commissioned by the Natural Resources Defense Council20 indicates that, even without science-based accounting for life-cycle CO2 emissions, the cost of onshore wind and solar power will likely be similar to or lower than that of coal-to-biomass conversions in 2020, and significantly lower in 2025. (The study did not examine dedicated biomass power stations, but the subsidy rate for these is higher because they are more expensive than coal-to-biomass conversions.)
Furthermore, while the capital cost of solar and wind power continues on a downward trend, there is no realistic prospect of biomass electricity costs coming down because combustion technologies are already mature, and because high dependence on imports make this sector vulnerable to changes in currency rates.
Stopping biomass subsidies and diverting funding towards sensibly sited wind and solar projects, as well as energy conservation and efficiency would help to reduce carbon emissions from the energy sector. Support for new onshore wind and solar PV, and increased support for community renewables wind and solar projects, and for home energy conservation are vital and viable alternatives to both coal and biomass electricity.
What is happening instead?
In 2015, instead of supporting a move to a different energy system we so desperately need, the government massively cut support for low-carbon technologies.
The cuts included:
- Ending support from the renewables obligation (RO) for new solar and onshore wind projects from April 2016
- Slashing the Feed-in-Tarriff (FiT) – which is only available to projects below 5MW – by 65%. This will hit community renewables and solar PV especially hard.
- Capping deployment of new solar schemes under the FiT at £100 million from 2016-201921
£100 million over 3 years may sound a large number initially, but it is disproportionately small compared to the yearly support for biomass electricity (£817 million last year) and for North Sea Oil and Gas (tax cuts worth £1 billion to the public purse in 2014-2015 alone).
- Imposed a six-to-eight-fold tax hike on businesses, community groups and schools who are generating their own electricity22
- The government have no national energy efficiency targets, and scrapped their commitment to zero-carbon homes and the Green Deal23. (Whilst the Green Deal had failed in its objectives, it was not replaced with a more meaningful scheme).
The result of these changes was highly damaging, and is continuing to be so:
- Research commissioned by the Solar Trade Association estimates that over 12,500 jobs in the solar industry will have been lost by the end of 2016 due to subsidies cuts24
- According to government statistics, there was a 93% fall in new solar installations25
- The government has revised down their projections of renewable energy installation, and now the UK is expected to miss its 2020 renewables targets26
- The government estimated the cuts are likely to result in 1.6 million more tonnes of CO2 being emitted27.
These cuts went ahead is despite the urgent global and national need for emissions reductions, and despite the growing success of community energy: community energy projects were spreading around the country, creating more localised forms of investment and economy and revitalising communities. Furthermore, as mentioned above, the costs of wind and solar are expected to continue to fall.
We desperately need to be moving away from old, inefficient, polluting and extractive technologies (such as oil, coal, gas and biomass) and towards a decarbonised energy system. There needs to be proper support for truly low-carbon renewables, but also, this can’t exist in a vacuum: there must be a well thought-through and holistic plan for transforming the energy system of this country, including reducing energy demand, massively updating the grid and storage, and investment in low carbon infrastructure – the list goes on, and it requires proportionate research and support. This also must be an energy system that works for the people of this country, being affordable and delivering warm homes, transport links that function and clean air to breathe.
Biofuelwatch supports the Reclaim Power declaration and works closely with community renewable energy projects and campaigns, as well as lobbying the government, MPs and other decision-makers.
1 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/552060/DUKES_2016_FINAL.pdf (http://www.telegraph.co.uk/business/2016/07/28/a-quarter-of-uk-electricity-was-generated-by-renewables-last-yea/ for summary)
2 This figure is based on Ofgem data available via ref.org.uk/generators/group/index.php?group=TechGroup and the average market price per ROC in 2015, which was £42.69.
3 For full references and details regarding the amount of biomass burned for electricity in the UK, see https://www.ofgem.gov.uk/publications-and-updates/biomass-sustainability-dataset-2014-15
4 DECC: lifecycle impacts of biomass electricity in 2020, p5. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/349024/BEAC_Report_290814.pdf Currently, biomass plants which have been approved or recently opened could burn over 23 million tonnes a year between them.
6 sciencedirect.com/science/article/pii/S0378112715001814 and sciencedirect.com/science/article/pii/S0961953411005502
7 For a list of relevant studies, see biofuelwatch.org.uk/biomass-resources/resources-on-biomass/
8 Raupach, M.R. et al., 2014. Sharing a quota on cumulative carbon emissions. Nature Climate Change, 4(10), pp.873–879. Available at: http://dx.doi.org/10.1038/nclimate2384.
9 https://www.nrdc.org/sites/default/files/southeast-biomass-exports-report.pdf p3
13 DECC: lifecycle impacts of biomass electricity in 2020, p11. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/349024/BEAC_Report_290814.pdf
17 Zhang, X. et. al. 2010. Biomass burning impact on PM 2.5 over the southeastern US during 2007: integrating chemically speciated FRM filter measurements, MODIS fire counts and PMF analysis. Atmospheric Chemistry and Physics,10(14), 6839-6853.
19 A study carried out by the Department of Energy and Climate Change (ref. 4) on carbon accounting of biomass feedstock found that burning whole trees from naturally-regenerating forests – which definitely makes up at least part of Drax’s feedstock – results in emissions of 3345 CO2e/MWh – over three times that of burning coal. The study calculated the emissions intensity of a variety of different feedstocks – for instance, from dedicated plantations and forestry residues. Of the 32 different scenarios, 6 result in greater emissions than coal burning, 9 produce greater emissions than gas burning and 17 produce emissions over 200 kg CO2/MWh – the legal limit.
25 Statistics here https://www.gov.uk/government/statistics/solar-photovoltaics-deployment. Summary: http://www.businessgreen.com/bg/news/2453010/decc-figures-reveal-93-per-cent-fall-in-uk-solar-deployment
26 https://www.carbonbrief.org/analysis-uk-government-quietly-slashes-renewable-energy-forecast and http://www.bbc.co.uk/news/science-environment-36710290
27 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/458662/IA_for_FITs_consultation_August_2015_-_FINAL_docx__e-signature_included__v2.pdf, reviewed by FoE here https://www.foe.co.uk/sites/default/files/downloads/solar-cuts-mp-briefing-2015-86837.pdf