Any energy that comes from using wood as a fuel source may be referred to as wood energy. While the term is not a common one, it accurately describes the fuel source and the benefit. Wood energy was once the dominant source of energy used in the world, but has since been replaced by fossil fuels in most areas. Still, there are many people who still depend on wood as a fuel source for energy in a number of different ways.
The most common way to get energy from wood is to burn the material. The heat produced from the fire can be used in a number of different ways. It can be used as space heating, such as with campfires or fireplaces. Also, it can be used for cooking, or even as a way to produce mechanical energy through the creation of steam, such as in locomotives and some power plants. That steam is then used to power gears or turbines to produce electrical or other forms of energy.
Currently, the United Nations estimates that wood energy supplies 14 percent of the world's energy needs. This percentage is much higher in developing countries, where other natural resources, or the ability to acquire fossil fuels, is not as great. Countries in such a situation tend to turn to the resources they have most readily available, which is often wood.
The use of such natural resources has led the United Nations' Food and Agriculture Program to help developing countries by formulating a sustainable plan for wood energy specific to the needs and supply in those countries. This helps these countries maintain a level of energy independence while their economies get a chance to develop further. Many of the countries currently using a great deal of wood energy are located in Sub-Saharan Africa.
The benefits of wood are numerous. In addition to being available in many different areas, wood also is considered a renewable form of energy because it can be replaced in a relatively short period of time. Also wood provides other benefits while growing, such as animal habitat and even carbon dioxide consumption.
The use of wood energy also is criticized by some. Many fear that harvesting wood disrupts wildlife too much, and may be used in a way that is unsustainable in some areas. In addition, although it helps take carbon dioxide out of the atmosphere, burning wood puts at least some of it back into the air.