Using biomass as a fuel means that carbon dioxide (CO₂) which was absorbed from the air while the plant was growing, is released back into the air when the fuel is burned. The system is said to be carbon neutral. Providing the balance is maintained between the plant growth and biomass use, the system is sustainable and helps combat climate change.

Global climate change is the major environmental issue of current times. Evidence for global climate change is accumulating and there is a growing consensus that the most important cause is humankind's interference in the natural cycle of greenhouse gases. Greenhouse gases get their name from their ability to trap the sun's heat in the earth's atmosphere – the so-called greenhouse effect.

CO₂ emissions are recognised as the most important contributor to this problem. Since the turn of the 20th century the atmospheric concentration of greenhouse gases has been increasing rapidly, and the two main causes have been identified as: burning of fossil fuels and land-use change, particularly deforestation. It is therefore important to stress that there is a vital difference between energy production from fossil fuels and from biomass. Burning fossil fuels releases CO₂ that has been locked up for millions of years in the ground and will require many more millions of years to return back to the ground. By contrast, burning biomass simply returns to the atmosphere the CO₂ that was absorbed as the plants grew over a relatively short period of time and there is no net release of CO₂ if the cycle of growth and harvest is sustained.

The concept of sustainability is summed up in the North American aboriginal idea of a forest for seven generations		Nearly 40 pupils took part in the Surrey Primary Schools' Earth Summit, a ground-breaking event designed to let young people voice their fears about the environment (© Surrey County Council)		Education about sustainable use of forest biomass in Slovenia