Significant savings in carbon dioxide emissions can also be achieved through bioenergy

Biomass-based energy – the oldest source of consumer energy known to mankind – has great potential in helping efforts to tackle climate change as well as meeting growing global demand for electricity and heat in a secure and sustainable way.

A new technology roadmap, released on 29 May by the International Energy Agency at the World Bioenergy 2012 conference in Jönköping, Sweden, projects that world bioenergy supply for the production of heat and electricity could double by 2050. For this to be achieved, around 100 exajoules (5 to 7 billion dry tonnes) of biomass per year will be needed by 2050.

Different uses of biomass

Bioenergy is derived from biomass, which includes any decomposing matter drawn from plants or animals that is available on a renewable basis, such as wood, agricultural crops, municipal organic wastes and manure.

It currently provides around 10% of the world’s primary energy supply, but most of this is in the form of inefficient traditional biomass used for cooking and heating in developing countries. This roadmap aims at the enhanced deployment of advanced biomass cookstoves and biogas systems to 320 million households in developing countries by 2030. This will be as an essential measure to reduce traditional biomass use, which is associated with severe health and environmental problems, and contribute to universal access to modern and sustainable energy.

From a global perspective, following concerted efforts to improve energy efficiency of buildings and to reduce the use of inefficient traditional systems, the roadmap envisions that bioenergy could supply 20% of total world heat demand in buildings by 2050. Moreover, in industry heat from biomass will become increasingly important in replacing carbon dioxide (CO₂) intensive fuels, such as coal and heating oil.

The strongest growth in bioenergy use is projected for the power sector, where biomass could provide 3000 terawatt hours (TWh) of electricity; more than a ten-fold increase compared to the 270 TWh generated in 2010) globally by 2050. This is the amount of electricity that is currently generated by all sources of energy in the European Union. In 2050, it will be enough to meet 7.5% of the world’s electricity demand.

Tackling climate change

“As well as potentially making a significant contribution to the world’s future energy supply, bioenergy can also help efforts to mitigate global warming,” said Bo Diczfalusy, IEA Director of Sustainable Energy Policy and Technology, at the launch.

“Using bioenergy for both heat and power could bring 2 gigatonnes of CO₂ equivalent emissions savings per year in 2050 compared to a business-as-usual scenario, 35% of which from biomass heat in industry and buildings,” he added. This is the equal to saving double the amount of energy-related CO₂ emissions that were emitted by Japan in 2009.

For this sizeable CO₂ reduction to be made, the IEA stresses that biomass feedstocks, such as wood chips, must be produced sustainably and used efficiently. This requires ensuring low or zero net emissions during the whole life-cycle; from planting to cultivation, transportation and conversion of biomass to energy.

To address key environmental, social and economic issues related to bioenergy production and use, governments should adopt sustainability requirements for bioenergy. The IEA roadmap stresses that these schemes should be internationally harmonised, to provide credible certification schemes and avoid market disturbance or the creation of trade barriers.

 IEA analysis suggests that enough biomass to meet the projected demand could be provided by harvesting residues and organic waste, as well as dedicated energy crop plantations on land not needed for agriculture.

Nonetheless, some uncertainties remain related to costs of biomass supply, the impact of large-scale plantations on land competition, and the possible sustainability impacts. The roadmap, therefore, calls for inter-mediate bioenergy targets that will eventually lead to doubling current world total primary bioenergy supply (for heat, power and biofuels) by 2030.

Achieving the targets

The roadmap highlights steps to take to realise the potential of bioenergy in the next 40 years.

Co-firing is flagged as an important, low-cost option, in addition to the development of large-scale biomass power plants. These plants allow for electricity generation at high efficiency and generation costs close to, or even lower than coal- and natural gas-based electricity under favourable circumstances today, and increasingly so in the future. Smaller-scale plants should be best-deployed in combined heat and power mode, when a sustained heat demand is available. Bioenergy can be a competitive source of heat in domestic as well as industrial applications today, particularly when replacing oil as a fuel.

The roadmap also stresses the need to enhance research, development and demonstration efforts to bring promising new technologies, such as small-scale, high efficiency cogeneration technologies to the market.

International trade in biomass will be vital, the roadmap argues, to match the required supply and demand in regions throughout the world which are making efforts to invest in this renewable source of energy. Technical standards for biomass feedstocks, as well as robust, internationally aligned sustainability certification will both be important measures to create a vital, international market for sustainable biomass.

The roadmap stresses that concerted action by all stakeholders in the bioenergy sector and related fields will be needed to achieve this vision of sustainable bioenergy supply. But governments must take the lead role in establishing a framework within which the production of bioenergy electricity and heat can develop in a sustainable way, including through integrated land-use management schemes that aim for a more efficient and sustainable production of food, feed, bioenergy and other services.

Abstracted from: "http://www.iea.org/newsroomandevents/news/2012/may/name,27319,en.html"