Wood for Energy
A new potential opportunity for marketing woodland produce is renewable energy for both heat and electricity production. Forest by-products such as early thinnings and small wood that might otherwise go to waste can be a valuable energy resource.
Processing timber in mills also produces large quantities of by-products which can be chipped for fuel.
Sources of wood for energy can be broadly grouped into:
Biomass
Biomass, comprising short rotation willow and poplar coppice, together with forestry residues and elephant grasses (Miscanthus) offer more than just renewable energy. Huge potential exists for biodiversity, rural jobs and income.
Planting fast-growing broadleaves, especially willows and poplars and managing them by coppicing has attracted a lot of attention recently.
Modern plant breeding is producing new lines of rapidly growing willows and poplars, which are often hybrids, which when planted and managed can be cut and harvested on a short rotation of four to six years.
The notion of growing trees for biomass is particularly attractive in areas where climatic and soil factors make agriculture marginal, but trees can grow. This is especially important where energy consumption per capita is low and there are scarce, or expensive, local fossil fuel resources.
Forest residues like smaller branches are produced as waste in woodland
management operations. Unsuitable for most current uses, they can be
chipped
for biomass for “green energy
”.
Firewood
Firewood is a cheap, non-fossil fuel from a renewable resource. Small-scale firewood production can help revitalize a declining rural economy. To cut logs properly and profitably needs a management plan and an outlet. Depending on the volume of wood to be cut, you may need a felling license from the Forestry Commission. Some trees make better firewood than others. Broadleaf trees are denser than conifers so provide more heat energy volume for volume.
Properly seasoned ash, oak, beech, birch, sycamore and hornbeam are all good firewood.
Conifers are prone to throw sparks as are sweet chestnut and turkey oak although they can be used very dry in a closed wood-burning stove or boiler.
Alder, willows and poplars are poor firewood due to their high moisture content although they are suitable for biomass production for burning in commercial boilers.
People often ask how much firewood they would need to heat their home and provide hot water each year. In round terms, a cottage would need 8 – 16 tonnes, a two or three bedroom family home 16 – 24, and a farmhouse 24 – 32. A 1 hectare (2.46 acres) broadleaved woodland should produce about 5 tones of fresh logs a year.
Although attractive, open fires are not efficient and may waste up to 85% of
the heat. Wood-burning stoves are more efficient and can be visually
attractive and larger models produce domestic hot water too.
Firewood
is a basic essential in the lives of many people worldwide.
Charcoal
The
use of charcoal in Europe can be traced back at least 5,500 years. In the
past, charcoal production was fundamental in Britain to provide the high
temperature fuels needed for industries such as glass-making and iron
smelting in medieval times. Charcoal was an important ingredient in
gunpowder production too.
While industrial use of charcoal has declined, Britain now burns around 60,000 tones a year for barbecues.
Most of that comes from abroad including the endangered mangrove forests of South East Asia.
Locally produced barbecue charcoal is becoming more readily available,
and is normally excellent quality. By buying it people support woodland
management and local rural employment.
