Electricity is a key part of today's society. It is used to provide light, heat, to cook our food and power the appliances we rely on every day at home and in the office. Global demand for electricity is c. 20 billion megawatt hours (MWh) per year, equivalent to the demand of c. 7 billion average UK homes. The vast majority of this electricity consumption is generated through the combustion of fossil fuels, mainly coal and gas, transforming chemical energy that has been formed through the operation of earth's processes over millions of years. The combustion of fossil fuels to extract this chemical energy involves the release of carbon compounds into the atmosphere, contributing to a new flow of carbon from the earth's land system to the atmospheric system. Electricity generation in this way has been responsible for a significant release of greenhouse gases into the atmosphere since the industrial revolution.
Whilst alternatives to fossil fuel electricity (e.g. renewables, nuclear) are increasing across the world, the generation of electricity from coal and gas continues to increase to serve growing global demand, in particular in rapidly developing countries such as China and India. Coal and gas provide reliable, baseload (i.e. consistent) and cheap supplies of electricity required to fuel growth in demand as populations both grow and increase consumption per capita through development; as well as demand from increasing industrial and commercial sectors. This is shown in the graph below.
