Eco Investor August 2013

Industry Focus

Producing Eco Friendly Bioenergy

A new report by the EU says that the environmental friendliness and efficiency of bioenergy is greater if it is used for heating rather than for transport fuel, if it does not displace existing unused natural land, and if it comes from a broad mix of crops.

The report, by the European Environment Agency (EEA), aims to limit the negative environmental impacts of biofuels and other forms of bioenergy for heating, power generation and transport.

It says bioenergy is an important part of the renewable energy mix - in 2010 bioenergy supplied about 7.5 per cent of EU energy and is forecast to rise to 10 per cent by 2020 or about half of the projected renewable energy output.

The report, EU Bioenergy from a Resource Efficiency Perspective, looks mainly at the potential for energy from agricultural land, but also includes forest and waste biomass.

It says bioenergy production must use resources more efficiently and should follow EU resource efficiency principles, which means extracting more energy from the same material input, and avoiding negative environmental effects. This means reducing the land and other resources needed to produce each unit of bioenergy.

Europe's current mix of energy crops is not favourable to the environment. To reduce environmental impacts, it recommends a broader range of crops, particularly perennial crops, which are not harvested annually. These could be energy grasses or short rotation willow plantations.

These crops would also enhance rather than harm what it calls 'ecosystem services' that are provided by farmland such as flood prevention and water filtration.

Although bioenergy is carbon neutral - in that the carbon dioxide released in combustion is assumed to be compensated by the carbon dioxide absorbed in plant growth - greenhouse gas savings can be negated if energy crops are grown on previously unused land that was forest or savannah. Converting these lands to agriculture harms biodiversity and increases greenhouse gas emissions.

Extensive use of mature trees for energy may have a negative effect on the climate due to the long time it takes for the trees to regrow and re-capture the carbon dioxide released when wood is used for energy.

This carbon debt does not arise if other forest biomass is used instead, such as branches left over from forest harvesting and by-products and waste products from timber and paper production, says the report.

Using organic waste and agricultural or forestry residues is more resource efficient than many other types of feedstock as it does not add pressure on land and water resources and offers very high greenhouse gas savings.

The EU's current EU bioenergy policies only partially account for the potentially adverse environmental effects of land use effects including changes in land management. Additional policies, particularly around water resources and farmland biodiversity, could help reduce these impacts.

The EU’s past and future mix of energy crops.

The analysis says the most efficient energy use of biomass is for heating and electricity and for advanced or second generation biofuels. First generation transport biofuels such as biodiesel from oilseed rape or ethanol from wheat are a far less efficient use of resources.

Biomass to energy conversion technologies vary significantly in their efficiency. Burning biomass to generate electricity is only 30 to 35 per cent efficient, while burning the same material to produce heat is usually over 85 per cent efficient.

So, in general, using bioenergy for heat and power is considerably more efficient in reducing greenhouse gas emissions compared to using bioenergy for transport fuel.

Energy cropping systems can also vary greatly in their productivity and environmental impacts. High yielding systems with efficient conversion can give over 20 times more energy than low yielding inefficient systems using the same land area.

The countries with the largest estimated agricultural bioenergy potential in 2020 are France, Germany, Spain, Italy, Poland and Romania.

The report develops three 'storylines' with different technological, economic and policy assumptions to explore different future options and illustrate which bioenergy types are most resource efficient and which have the lowest environmental impact.

EEA executive director, Hans Bruyninckx, said "This study highlights the fact that forest biomass and productive land are limited resources, and part of Europe's 'natural capital'. So it is essential that we consider how we can use existing resources efficiently before we impose additional demands on land for energy production."

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