We need energy for everything we do. For our bodies the energy comes from food. But for everything else, like the machines we depend on for our transport, communications, entertainment and health, we need to produce energy. Though we normally use the word ‘produce’ the total amount of energy in the universe is, in a sense, fixed. So when we commonly speak of production, we mean the conversion of it from one form to another, usually in order to perform work.

The word energy is derived from the Greek ‘energos’, meaning work. At the dawn of the Industrial Revolution, human muscle provided 70% of the energy needed; the rest came from wind, sun and water.

The burning of coal provided most of the energy needed for the Industrial Revolution. This coal-burning actually released millions of years of stored energy made by plants from photosynthesis. These fossilised plants turned into coal and oil, hence the term ‘fossil fuel’. During the Industrial Revolution, thanks to coal, the total energy use by humans worldwide increased by a factor of five, while the discovery of oil and natural gas increased energy usage by another 16 times. These fossil fuels currently account for 86% of the world’s energy.

• Crude oil accounts for 39% of global energy.
• It is followed by coal, at 24%.
• Then comes natural gas with 23%.

But it is the richest nations that use most of this energy. The United States alone, with just 3% of the world’s population consumes 25% of global energy, whereas 2 billion people, primarily in Africa and developing Asia, do not have access to fossil fuels and rely on wood as their sole source of energy.

The connection between energy use and poverty is quite clear. Access to cheap and plentiful fossil fuels has enabled the western, more industrialised world, to enjoy high standards of life, while lack of energy access has kept other countries in poverty. And because of this many countries are willing to do anything to keep their access to energy sources like oil and coal, including start and fight wars.

Many other problems are related to energy use. When one form of energy is converted into another to perform work, because of the inefficiency of our machines and the quality of our energy sources, only a portion is obtained as energy; the rest is given off as heat and waste gasses and ash. These waste products, especially the waste gasses, are a major factor in global warming. This, coupled with problems of availability, has lead to the search for other sources of power. But they are going to be difficult to find and many of them have their own environmental problems. And our dependence of fossil fuels -- most obviously in the case of oil to power cars and other forms of transport -- is going to be very hard to give up.

In India, many alternatives to fossil fuels exist and are regularly used. These range from high technology alternatives like nuclear power, which is used to generate electricity, to dried cow dung used for household heating and to cook food.

Wood
But of all the alternative sources of energy used in India and the rest of the developing world one of the most interesting is wood. People burn wood to heat their houses and keep warm. Compared to other sources, wood fire seems very basic and in some ways primitive. It was probably the first source of energy when man first evolved, and some people credit our understanding of managing fire as a first step in the process of civilisation. Yet even now, 70% of the world’s developing population relies on wood for its primary fuel. It is a fuel of poor or poorer people, those who cannot afford gas and electricity. (In most developed nations, wood accounts for less than 3% of total energy.)

Africa has the highest wood fuel use per capita, and wood provides over 45% of the continent’s energy needs. In some countries, notably Uganda, Rwanda and Tanzania, wood accounts for 80% of total energy.

In India, wood accounts for around 20–30% of the total energy consumption in the country. Most of this, 90% of the total quantity of wood, is used in the domestic sector, for cooking and heating water. Wood is also used at cremations, and in small hotels or eating places like dhabas.

The first thing that needs to be understood about wood is that although we speak of it as one thing it is actually quite varied and of different ‘economic’ types. Wood from larger trees is used as timber, for building and for making furniture. But this is valuable and too expensive to be burnt as firewood. It is mostly smaller tree branches, twigs, wood shavings, bark and roots, all which cannot be used elsewhere because they are of inferior quality, that are used for burning. Most of this kind of wood falls off trees or can be cut off without damaging the living tree itself, which continues to grow to provide more wood for burning later. Also used are cast-offs and waste material from sawmills and timber factories. Except for the time and energy required to collect and carry the wood home from the forest or sawmill, this energy source is free which is why poor people depend on it. People who live far away from electric power lines and roads depend on wood because they have no choice. In many cases, people who can collect wood because they live near or have access to a forest collect more than they need and sell the rest; even in these cases wood works out cheaper than other sources. This is especially true for urban poor people who may have access to other sources of energy if they can afford it, but prefer wood since it is much cheaper. Generally it has been found that when people get richer they move on to cooking with coal, kerosene, electricity, or liquid petroleum gas, all of which need to be bought.

Apart from its cheapness there are some other very positive things about using wood as fuel. Wood is renewable and if properly maintained can be self-sustaining. Although wood use as fuel has supposedly contributed to the degradation of forests, around two-thirds of wood used for fuel comes from non-forested areas. It needs very little physical or chemical inputs to make trees grow. Waste products like ash can be returned to the environment and helps maintain the soil. An advantage of wood is that it contributes much less greenhouse gases than fossil fuel.

But there are also problems with using wood. One of these is that people who are too poor to afford other forms of fuel are usually also too poor to afford proper ventilation for their homes or even stoves that are efficient. This leads to the waste gases from burning wood being a major cause of respiratory illnesses. A second problem stems from the fact that in most Indian rural communities it is generally women who collect wood, spending a lot of time roaming in the forests trying to collect enough to help their families survive. This adds on to the time women spend collecting fodder and water, meaning that when young, they are the ones who drop out of school to perform these time-consuming and occasionally dangerous chores, adding to the gap in education between men and women.