In the late 1980s the need to reduce agricultural surpluses resulted in large areas of land being release from agricultural production and the planting of SRC on this land is now eligible under the Woodland Grant Scheme. The Rio Agreement of 1992 set new national targets for the reduction of carbon dioxide and sulphur emissions. This was followed in 1994 by The Declaration of Madrid. Which set the objective of substituting 15% or real primary energy demand in the EU by 2010,
Based on 1990 levels, with renewable energy sources. More recently, the Kyoto Climate Change Conference (1997), with its legally binding target of reducing greenhouse gases by 8% by 2010 has raised the profile of biomass energy production. In the UK there is now increasing interest in the use of SRC as a renewable energy source, especially with the construction of Britain’s first predominantly SRC fuelled power station. The ground Work for this power station commenced in summer 1997. The use of SRC of willow and poplar as a substitute for fossil fuels is environmentally beneficial as it produces no net CO2 emissions from its combustion. Typically 30 MJ of energy can be produced from 1 MJ input of non- renewable energy in growing and harvesting the crop (Matthews et al., 1994). The carbon budget is more favourable when yield is maximised. The combustion of coppice also produces emissions low in nitrogen and sulphur pollutants compared with fossil fuels. The EC white Paper “Energy for the future: Renewable sources of energy” (European Commission, 1997) suggests that biomass could contribute 27 million tonnes oil equivalent (Mtoe) of solid biomass by 2010, which would imply a cultivated area of 6.3 million hectares of land
Research in the 1980s and early 1990s has indicated that willow and poplar clones offer the best potential, and has indicated the yields which might be expected. However, this yield information was based on a restricted data-set, which covered only limited site types. Sound yield predictions, based on a full range of available site types, are therefore needed by potential investors in power stations capable of using wood fuel, by policy makers for determining support regimes and by farmers for deciding whether to become involved in wood fuel production.
This project (Phase IV of the site yield project) will investigate the potential yield of a number of willow and poplar clones over a range of different site conditions. The results from these trials will be used to inform power generations, policy makers and farmers on potential yields and the optimum choice of clones for particular locations. Forty eight sites have been established in earlier phases of this project and soil, meteorological data and yield data are being collected, verified and stored in data banks.