New technology will give us energy for the future
Most of the energy we use today comes from fossil fuels. Whenever we heat our buildings or use electricity at home or at work we are contributing to global carbon dioxide emissions and the accelerating greenhouse problem. Using energy more efficiently and turning to alternative sources of energy have to be high priorities now and in the future.
Energy can be divided into renewable and non-renewable forms. Non-renewable energy comes from the Earth’s reserves and takes the form of fossil fuels or nuclear power. Renewable energy sources can be divided into flow resources and stored resources.
The main non-renewable sources of energy are fossil fuels such as oil, coal and natural gas. When fossil fuels are burned they produce carbon dioxide, which contributes to the greenhouse effect. The burning of coal releases the most carbon dioxide, while natural gas releases the least.
Renewable energy sources can be divided into flow resources and stored resources. Wind, sun and water are all flow resources.
Stored resources are bioenergy that we harvest from the fields and forests. These are sources that store energy from the sun, and when used at the correct rate can be regarded as inexhaustible.
This latter category also includes biogas that is produced when household waste and other biodegradable waste break down in the absence of oxygen. Biogas can be extracted from water treatment plants, landfills and other sites where biodegradable material is collected.
One third of the energy that is used in Sweden at present comes from renewable energy sources. The proportion of bioenergy has more than doubled since 1970, but this share needs to increase further if we are to reduce our negative impact on the climate.