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Biomass CO2 Emissions More Than Burning Coal

August 27, 2014

By Paul Homewood




Back in May, I reported on a letter sent to Ed Davey by a group of American scientists, attacking UK subsidies for biomass plants. They pointed out that burning biomass could actually increase CO2 emissions, as well as causing other environmental problems.

DECC were so alarmed that they had to commission a report.

It seems that even the BBC, belatedly, have picked up on this problem. In July they reported:


Burning wood to fuel power stations can create as many harmful carbon emissions as burning coal, according to a government report.

UK taxpayers subsidise energy firms to burn wood to meet EU renewables targets.

But the report from the Department of Energy and Climate Change (DECC) shows sometimes much bigger carbon savings would be achieved by leaving the wood in the forests.

This suggests power firms may be winning subsidies for inadvertently making climate change even worse.

The report has caused controversy within DECC as it indicates the initial subsidy rules were much too simplistic.

The government has now promised to strengthen the regulations on burning wood, and to make standards mandatory.

Environmentalists applauded the move but said they wanted to see details and a timetable for the new rules. They insisted that the proposed new regulations must be based on the new document.


Burning biomass – such as wood – is not a zero-pollution option. It creates greenhouse gases to cut and transport the wood, and when the wood is burned.

But supporters say that so long as the burned vegetation is replaced by new plants to absorb CO2 that should confer a significant advantage over using fossil fuels.

And it counts as renewable energy because new trees soak up the CO2 emitted by the burned trees.

The DECC report says a key error in the government’s previous calculations was a failure to acknowledge the different types of impact that can be created in different types of forests when wood is removed to burn.

Burning whole logs from natural forests would be counter-productive, the report says, whilst generating power from wood waste that would otherwise be burned at the roadside could provide benefits for the environment overall.

DECC stepped up research on the issue after a paper by a US academic showed that burning whole trees would produce more emissions than burning coal, by the time transport emissions are taken into account.

"When we first saw this research we didn’t believe it," a government source told BBC News. "But we did the calculations and found that we had been wrong."


Commercial forestry

He added: "This is really embarrassing for the government – they have finally admitted what we have been saying for a very long time.

"Under the current rules there is no way of government knowing whether wood is being burned in a way that is beneficial to the climate or not."

The UK’s biggest power station, Drax, is switching half of its boilers from coal to wood pellets in a plan to reduce greenhouse gas emissions.

The firm insists that it is using off-cuts of wood that would otherwise be waste. But the issue is complex and disputed.

The firm has a wood pellet operations in the USA, which collect thinnings and off-cuts from trees. This is wood deemed appropriate to use in power stations.

But there is another wood pellet plant sending biomass to the UK using whole trees from endangered swamp forests.

So the DECC calculator may help government and industry determine exactly what sort of biomass it is useful to burn, but the evidence will be scattered between multiple producers in supply chains thousands of miles away.

The report says there may be enough spare waste wood in America’s forests to supply current UK demand sustainably.

But knock-on effects are hard to calculate across an entire industry.

Drax - wood fuel

Drax power station says it uses offcuts of wood that would otherwise be waste


What is the effect on soil structure and nutrients of clearing all the waste wood from a felled forest?

What if the price for burnable wood outstrips the price for wood pulp, and forces the USA to import wood from elsewhere to make its paper products?

American researchers wrote to the UK Energy Secretary Ed Davey saying that UK biomass policies were harming wildlife in the USA, and I understand Mr Davey sees biomass burning as a temporary solution to meet short-term carbon reduction targets.

The subsidies last until 2027. Policy uncertainty after that date means investors may soon stop building new wood pelleting plants in the USA.



Common Sense

To most of us this would all be common sense.

One revealing comments is that the initial subsidy rules were much too simplistic. What else can you expect when people like Davey and his ex Chief Scientist sidekick, David Mackay, are left in charge of formulating energy policy.

The defenders of biomass, including those paid enormous subsidies to burn the stuff, will no doubt argue that the wood they use is “good wood”, as Drax argue. But, as is pointed out, the knock on effects are incalculable. Diverting wood supplies from the wood pulp market will force the latter to look elsewhere, and thereby simple transfer the problem to somewhere else.


Not only, but also!

Of course, it does not help emissions when the wood pellets burn when they not supposed to.




Chief Fire Officer Johnson said it was one of the most challenging fires he has had to deal with in his 20 year career.

He added: "The fire involves up to 6,000 tonnes of biomass high up in the power station building. The fuel goes into vats and is taking into the plant on a conveyor belt.

"The fuel cells are designed to carry dry fuel so pouring water onto them and making them significantly heavier could potentially damage the structure of the building."

Tilbury opened in 1969. It use to operate as a coal-fired power station but has been converted to generate power from 100 per cent sustainable biomass until its scheduled closure at the end of 2015.

Biomass plants burn wood pellets, generally made from compacted sawdust or other wastes from sawmilling and other manufactured wood products.




Not to mention:




  1. John F. Hultquist permalink
    August 27, 2014 5:16 pm

    from wood waste that would otherwise be burned at the roadside
    The firm insists that it is using off-cuts of wood that would otherwise be waste.

    Above statements are obfuscation.

    In the forests of Pennsylvania of the 1800s and early 1900s parts of trees and sawdust from many small mills were left in piles to slowly decay. About the mid-1950s this began to change to what is now full use of the resource. Particle board and co-generation are the norm. See this chart from OR/WA for the thermal power from such use (the brown line; scroll down to see the sources – while there – note the wind power, or not).

    Do the ships carrying wood pellets across the oceans use canvas sails or are the sails made from petroleum products?

  2. August 27, 2014 5:22 pm

    When science is driven by ideology, bad science is produced,
    Congratulations for starting to set things straight.

  3. tom0mason permalink
    August 27, 2014 11:58 pm

    IMO over the years, when science is driven by ideology, little or no science is produced. If anything, on some occasions, a particularly pernicious nonsense is produced.
    This BBC piece has all the hallmarks of pernicious nonsense, the name Roger Harrabin afixed to it is an unnecessary flurish of conformation.

  4. August 28, 2014 8:43 am

    Reblogged this on Tallbloke's Talkshop and commented:
    Bubble bursts for Britain’s biomass burning boom

  5. August 28, 2014 11:49 am

    Reblogged this on and commented:
    Making and shipping wood pellets, a fuel with lower energy density, from the US to the UK to replace coal never sounded like a good idea.

  6. August 28, 2014 6:48 pm

    This is so obvious, it’s unbelievable. But then most DECC policies are unbelievable.

  7. winter37 permalink
    August 30, 2014 5:42 pm

    Looking at the charts from engineering sources show that the burning of wood/straw/grass releases more CO2 than coal,and have lower energy densities.
    On the 15 Sept.2011,the European Environment Agency Committee issued a letter detailing the fact that the burning of wood is definitely not Carbon neutral.What happened to the letter,why was it ignored,and why are we being lied to.

  8. David A permalink
    September 1, 2014 7:19 am

    “And it counts as renewable energy because new trees soak up the CO2 emitted by the burned trees”
    Hum? Now new trees ignore additional CO2 from coal, but soak up CO2 from burning wood? Damm discriminating trees. (It is amazing what climate science can do with trees.)


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