Page last updated at 16:57 GMT, Tuesday, 29 July 2008 17:57 UK

Time to encourage biomass growth

David Williams
David Williams

Biomass energy is being touted as a key player in the push to green Europe's electricity supplies, says David Williams. In this week's Green Room, he argues that although there are promising signs, more needs to be done to encourage large-scale developments.

Chinese farmers transporting bales of straw (Getty Images)
Utilising straw for biomass represents one of the most efficient methods of its disposal and pre-empts the need for it to be ploughed back into the land
For some time, biomass has been seen as the emerging sibling of the renewable energy industry.

Despite much of the development behind the industry's technology worldwide, the UK's position at the front of the biomass revolution has been slipping.

Developers have naturally concentrated on cheaper forms of alternative energy, chiefly onshore wind, whilst other countries have stolen a march, with the Chinese particularly active by building hundreds of stations based on UK power plant models.

In recent months, however, we have seen something of a change in the UK, with a backlash against many more established alternative energy sources.

In the transport sector, biofuels have been attacked for their effect on food prices and actual carbon reductions, while wind has been criticised for its inability to produce a consistent stream of electricity and for its cost.

Many industry experts are now suggesting that biomass has to play the primary role in helping the EU to meet its challenging target of generating 20% of its energy from renewable sources by 2020.

Burning ambitions

Biomass works by converting (normally through burning) biodegradable matter such as wood, straw and agricultural wastes into heat or electricity.

Biomass storage silo (Getty Images)
Emissions from transporting feedstock can wipe out carbon savings

Because it uses organic materials, any carbon dioxide released during the generation of energy is offset by that absorbed during the plant's life, so the process as a whole is broadly balanced, or "carbon neutral".

Crucially, it is an effective method of producing energy.

A single power station can produce around three times more energy as a windfarm for the same amount of generation capacity. It is also reliable and can be scaled up or down to meet consumer demand.

Of course, every technology has its drawbacks and there has been criticism of biomass because of its sourcing needs.

The requirements to power a single station can be extensive, particularly if it is using wood as its primary fuel source.

Some plants within the UK propose to import timber from as far away as Canada and Indonesia; this can potentially have a huge impact on the carbon footprint of the feedstock and the energy that it produces.

That's not to say that all biomass projects suffer from these issues. Some developers are now looking to generate energy by burning straw, which the UK has an abundant supply of and which, as a by-product of agricultural crops, does not have an impact on the food verses fuel debate currently engulfing the biofuel industry.

Supermarket giant Tesco has recently been given a green light to build Britain's first ever straw-powered Combined Heat and Power (CHP) plant to meet the electricity and heating needs of one of its distribution centres.

Utilising straw for biomass represents one of the most efficient methods for its disposal and pre-empts the need for it to be ploughed back into the land.

As a final, but vital, benefit, the UK can meet all of its requirements from domestic sources, cutting out the need to import supplies and allaying growing concerns over energy security.

Whereas heat for domestic-scale commercial installations could come from solar technologies or even heat pumps, it is widely acknowledged that the primary market can only be supplied by biomass.

After all, most heat comes from combustion of a fuel, and biomass is the only renewable and combustible fuel.

Red tape fears

So what next for the industry? More than 3.5bn ($7bn) was invested last year and this figure looks set to grow substantially, as green investment funds try to hedge against the credit crunch by diversifying their portfolio of renewables schemes.

wind farm
Wind power and biomass are likely to be the key renewable technologies

Already a stream of projects are either coming online or expecting to do so shortly, including the world's largest plant near Port Talbot, South Wales.

Signs from government are also encouraging. Changes to its proposed Renewables Obligation Certificate (which offers incentives to suppliers to generate energy from renewable sources) will increase the value of energy generated by biomass in comparison with other sustainable technologies and make it more rewarding for investors to back.

In June, the Department for Business, Enterprise and Regulatory Reform (BERR) published its Renewable Energy Strategy that also made clear the important role that the industry could play, noting that there is a need to "develop a sustainable biomass market".

While this in itself is encouraging, there remains some concern over the detail.

The proposals mooted in the strategy have been primarily designed to make individual action more palatable, specifically a feed-in tariff to encourage microgeneration technologies in homes and a financial incentive mechanism to facilitate a general increase in use of renewable heat.

What they have not done, however, is to provide significant encouragement for commercial developers. There is a definite feeling by many in the industry that the current system is over-complicated and that applications are too frequently caught up in red tape.

By laying down a clear pathway that developers can follow, the government will be able to stimulate growth and at the same time provide the financial community with the confidence necessary for it to make the long-term substantial investments.

The result will be a step-change in the UK renewable sector as a whole, and the first step towards meeting the EU's 2020 targets.

David Williams is chief executive of renewable energy business Eco 2. He is also a member of the government's Renewable Energy Advisory Board and chairman of the biomass sub-group

The Green Room is a series of opinion articles on environmental topics running weekly on the BBC News website

Do you agree with David Williams? Can biomass play a key role in delivering the EU's 2020 target? Do governments need to do more to encourage the level of investment needed in order to build large-scale plants? Will an expanding global biomass sector lead to the need to import feedstock from all corners of the planet?

As I understand it, straw is ploughed back into the ground to improve soil conditions for crops. If the straw goes to biomass we may well get lower crop yields and even heavier use of oil based fertilizers. Perhaps there is a correlation between a surplus of straw and declining soil quality too.

Sorry, I need to hear what farmers, especially organic farmers, have to say about this!
Ron Robins, Huntsville, Canada

There are lots of crops, such as hemp, clover, and flax, which actually put nitrates back in the soil - no need for oil-based fertiliser there, just crop rotation. Critically, 80% of the UK's farmland is used for livestock rearing, and livestock takes up 7 times the land used for biomass - as well as being one of the major polluters of air, land, and water, being the major player in desertification of the planet, and using more water than can be sustained. We're eating more animal products every day than we have ever used at any time in the history of humanity. Replacing all (OK, being realistic, most) livestock farming with crop raising, including crops for biomass, is surely the single biggest thing we can do to save ourselves from massive environmental catastrophe. We know that Bad Things Will Happen. We're on damage limitation now.
Kaz, Macclesfield, UK

As David Gayler stated, (some) biomass is not 100% renewable. However some forms of biomass, for example Miscanthus, can be considered truely renewable due to their highly efficient nutrient retrieval during senescence. During harvesting barely any trace elements and a very low proportion of proteins (nitrogen) are removed from the land. This means stands of Miscanthus can be highly productive for a decade or longer with no additional fertiliser inputs.

However, even so, my own personal feeling is that only a hydrogen economy, primarily derived from geothermal, solar, wind and water renewable sources is practical. Quite bluntly, the rapidly increasing human population will prevent the wide spread use of biofuels as we have to strive continually to boost food production. The only true light at the end of the tunnel will be when global family size restrictions are put in place at a maximum of 1 child per person to prevent our population vastly exceeding the possible productivity of our fragile planet.
Richard Hayes, Aberystwyth, UK

There is one biomass plant that naturally gives 3 crops a year, with technology could give 6 crops a year, is nutrient neutral, needs no pesticides or fertilizers, is used in soil remediation and every part of the plant is useful. Unfortunately GW Bush is waging war against it, it's called Cannabis Hemp.
Peter, Surbiton

An interesting article - but you seem to have missed out the role that anaerobic digestion of existing organic wastes could play here. This is an area with big potential - one tonne of food waste produces enough biogas to run a car around 1000km. We produce in the UK around 6.7 million tonnes of this waste per annum. Given that the average UK car travels around 16000km per annum, using this resource to produce roadfuel could provide enough carbon-neutral fuel to run around 420000 cars. The residue from this process? A compost-like output which can be returned to the soil, a liquid fertiliser and hot water from the gas-engines. The AD of agricultural slurry and other material brings further possibilities. Not all biofuels are a bad environmental option - some are a considerable improvement on current practices, and reduce carbon footprint markedly.
Adrian Jones, Lydney, Glos

I don't know why the focus is so much on these 'aggressive' bio mass systems, rather than the less efficient but more ecological 'passive' ones: we have one in the region which heats a local swimming pool and school using the heat from animal excrement; but these are not burned only left to decompose/ferment/compost, so in the end the farmers that brought the stuff can leave with better quality fertiliser. It might burn the gas produced by the waste, but other than that does not generate CO2, just exploit the heat generated by a natural process, and return the Carbon in solid form into the soil. It seems a better idea than burning wood and straw, which are raw material that can be used in more productive/constructive ways.

Plus, I'm always surprised that only 'animal waste' is used - why not human waste and all that food we throw away? OK, some pathogens that survive in the heat produced and outside the body would have to be killed, but that can be done...!
Nadine Hengen, Luxembourg

Biomass seems a good idea. Here's another one: my parents' house in Germany was heated by a powerstation burning rubbish for heat. Cheap and also solving the problem of running out of landfill space.
Elena Tompkins, Manchester

Every green solution seems to turn out the same - a lot of green PR - a huge expensive rush based on trying to clutch at carbon targets - then the realisation it isn't quite that simple and in all there enthusiasm and ideogoloy there was no point of ration reflection or even doing the basic maths - the whole idea of so called renewables/sustainables is somewhat flawed - perhaps some in the future will produce good results at a reasonable cost but until then we need to clean up coal and do what scares the more superstitious greens silly - Nuclear power - it may not have the psuedo-rustic asthetic charm of wind turbines which wind supporters seem to desire but we stand a better of actually getting clean reliable energy
Robin, midlands

I agree with some of these comments. While biomass has a role to play, particularly in localised CHP stations (combined heat and power), I have not yet seen any figures which suggest that a realistic proportion of our biomass could be sourced domestically, perhaps I am wrong. Furthermore removing nutrients from the soil must be done with extreme care (in Brazilian sugarcane they must leave 30%-40% of waste in the fields)... Finally, biomass, like biofuels, greatly increases the demands on the land, and while it could have some benefits in the expansion of (hopefully) sustainable forestry, it could also lead to the profliferation of mononculture tree and switchgrass crops.. handle with care.
Alasdair Cameron, Edinburgh/London

As usual, the ecological impacts of a supposedly "sustainable" fuel are hardly mentioned. There is already substantial controversy over use of home-grown wood (eg from coppice) due to its impact on true forest wildlife (which is replaced by more generalist species). Imagine the risks of sourcing wood from overseas, where there are still many species sensitive to loss of forest canopy!

Also as usual, advocates of "renewables" do not stress (or know) the human health risks; the agricultural, transport and conversion process risks in biomass may be far higher than for some conventional sources.

The problems of biofuels (which have apparently surprised some sectors) were predicted years ago by ecologists, so let's not make the same mistake with other types of biomass. Put more effort into efficiency - and remember some forms of ecological damage (such as extinction) have environmental implications over an even longer term than climate change.
Clive Hambler, Oxford, UK

Some aspects of biomass are okay. However in the future a new approach to food production must be looked at. Fertile soil is responsible for 97% of the world's food production. Good top soil is being lost 20 times faster than it is being regenerated according to David Montgomery of University of Washington, Seattle. Therefore crops like wheat,corn,rice should be GMed to become perennials. This would eliminate straw from the equation in biofuels.

Global warming and the rise of CO2 pales into insignificance compared to soil depletion and atmospheric oxygen depletion.As Prof. Daniel Kammen, green advisor to Obama, stated in a National Geographic (Aug.05) article on climate change "We will run out of atmosphere before we run out of fossil fuels."

Anything that uses oxygen for transport and electric power generation must be quickly replaced where possible.
david clemow, Auckland. New Zealand.

Biomass is absolutely the right way to go. Care should be taken not to monocrop to get biomass, instead use should be made of balanced eco-systems. That's the beauty of biomass, one doesn't need to monocrop.
Pat O'Green, johannesburg

Biomass is an essential component of future energy policy, either from straw, coppiced trees or agricultural waste. Biogas (Methane) made from farm waste and sewage by anaerobic digestion also needs to be exploited. Both sources are ideal for supplying local CHP (Combined heat and power) plants.
John E, Southampton

Some additional elements should be added for viability. E.g. 1. Human sewage can be used for biomass crop fertiliser. 2. Biomass power stations can be run either in combined heat and power mode or as backup for other renewables.
Malcolm, Wirral, UK

Presumably the ash will contain the phosphorus, potash, etc which can be ploughed back in. The current system of ploughing in straw means that pellets are needed to contain slugs: I suspect this is behind the collapse of the sparrow population. The humus reduction didn't seem to matter in the past, when straw burning on the fields was the accepted way of getting rid of an unwanted by-product.

Of course there are downsides,but they are a lot fewer than the alternatives like coal and oil. Maybe we could also start burning all the plastic waste from dustbins and stop exporting it to China, where, no doubt, they just shove it on a bonfire.

Julian Flood, Suffolk, UK

Why can't something be done to improve the efficiency of our existing power stations? Take Drax for example, it has 6 or 7 huge cooling towers. That represents a large amount of wasted energy in the form of heat being released into the atmosphere. Coastal power stations release waste heat into the sea. Surely someone must be able to come up with a way to make better use of this energy? If only we could improve the efficiency of the supply side, then that would make a vast difference to the amount of generating capacity we need.
Derek Power, Uxbridge, UK

Monoculture biomass is not good for climate change. Sure you can grow a field of it for a few years and cart it all offsite, but pretty soon if you're not ploughing back the plant material goodness into the earth the soil will degrade. After not many years you will be left with increasingly dusty soil that can be blown away in a strong gale - see China, Brazil, USA right now for evidence of that.

The thing is soils are living eco-systems and if you only take and never give back they will dry and die and eventually just blow away with the wind. You're then left with dry, arid conditions that will grow little in comparison to the nice rich soil that used to be there. And it takes a millenia or two of undisturbed nature to create a decent layer new soil.

For biomass to be "sustainable", do what our forebears did and harvest a small fraction of a mature forest each year, and plant for the next generation.
Andrew Smith, Milton Keynes, UK

Biofuels in general is a good example of policymakers rushing to implement a promising concept without considering the long-term effects. The biofuels industry is already a major driver in the destruction of natural habitat worldwide (Brasilian and Indonesian rainforest is flattened for sugar cane and oil palms), as well as driving up food prices for the world's poor.
Jakob Tendel, Hannover, Germany

What happens to the nutrients in sewage? If these could be harvested and used to provide the fertilzer for biomass production, then surely this would make biomass a renewable source of energy production?
Robin Witt, Frome. England

Dale and David seem to have hit the nail on the head. Plowing back, adapting to how the earth requires us to live in order for the system to work and not the other way around.

All the solutions we are developing to combat climate change and the effects of global warming are simply diversionary and not preventative. At some point we have to take responsibility and change our lifestyles rather dramatically if we are ever going to overcome the problems we face.

I think Dale is spot on again when he says England's power to set an example to follow is enormous. Lets start by not shipping millions of tons of biomass fuel over our borders and into our power grids.
Luke Milnes, Sheffield

This is another miracle cure just like biofuels were supposed to be. It's highly misleading to say that burning dead matter is carbon neutral or renewable. Fossil fuel is a form of biomass that has simply been lying around longer. It's inevitable that not all plant matter burned will be replaced and a globalised economy will ensure that most of the fuel comes from "cheap" third world forests, further exacerbating climate change, environmental degradation, and exploitation of the impoverished.
Daniel Layton, Washington D.C.

Long/Medium term, crops grown in the ground will not be used for fuel. The whole biofuel industry is stalled as it is not sustainable. The answer, of course, is ALGAE. It is a matter of time; many people are anxiously asking when. Imminent energy revolution waiting for algae. Gonna be cool & extremely Earth-friendly.
colin, Seattle, WA

Even with the drawbacks of having wind and solar energy, with its fluctuating amounts of energy generated, it is by far much more reliable than having a system that banks on 20% of its energy supplied by biomass. With wind and solar energy the supply is already there. It just requires more research and advancements to fully harness its power. You could argue that biomass is already there, in readily available forms, but if you factor in the speed at which you would burn through these resources the argument is already settled. It isn't sustainable.

Focus on CHP plants would ultimately strain the already fragile environment. I just see it as another alibi for deforestation.
Michael Enriquez, West Jordan, Utah, USA

As the article says, transporting feedstock negates the carbon efficiency. So large plants are therefore a bad idea. A better one would be more smaller plants. This may be less efficient generation wise but more carbon efficient. Therefore a tradeoff needs to be found for an optimal size that generates efficiently yet does not need feedstock from a long distance away.
Muscleguy, Dundee

Biomass is absolutely the largest of all the renewables. In the future, we can couple biomass to carbon capture and storage (CSS), and generate revolutionary "carbon-negative" energy. That is, energy which takes CO2 out of the atmosphere!

Consider this: traditional renewables (wind, solar) are always carbon-positive - over their lifecycle they add small amounts of CO2 to the atmosphere. For wind this is around 30 tons of CO2eq per GWh. For solar PV 100 tons CO2eq per GWh.

Biomass coupled to CCS generates "negative emissions". These can be as large as -1000 tons of CO2 per GWh.

In short, carbon-negative biomass allows us to use energy while scrubbing the atmosphere.

Top climate scientists like Dr James Hansen have called on this type of carbon-negative bioenergy in order to reduce atmospheric CO2 levels to 350ppm. Wind and solar - being carbon-positive - can never pull this off. Even if we were to switch all of our energy to renewables, global CO2 levels will still rise to catastrophic levels.

We need energy that can actively withdraw CO2 from the atmosphere. And biomass is the key to this concept.
Jonas Van Den Berg, Brussels

I disagree that this is the road to follow. Sure it might make reaching targets twelve years out easier and build enterprise but it does so at a heavy cost. The cost of the retentive and restorative properties of the soil to both retain carbon and support plant life. The less the land is laid bare the more it can contribute to a healthy water cycle and hold onto a micro-ecology that can hold nutrients and help reverse global warming. Plowing back is what is needed to build a healthy environment not fuel based power stations. The longer society remains in denial that a fundamental change needs to occur in the way we think of things the harder it's going to be to stop global warming. England's climate is not typical of the rest of the world but its power to set and example to follow is enormous.
Dale Lanan, Longmont, Colorado, USA

Just a minor point: Biomass is not renewable. There is no free lunch. Whatever you take from the soil, sooner or later must be replaced - even the pioneers of crop rotation understood this truth. So if you continually strip out biomass, be prepared to add yet more fertilizer. In addition, in some parts of the UK, ploughing straw (for example) back in is essential to maintain a friable, breathing top soil full of helpful fauna.
David Gayler, Gloucester, UK

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