The average home creates around 6-7 tonnes of carbon dioxide every year from the energy it uses. Some of this comes from fossil fuels actually burnt in the home such as gas in a central heating boiler or from electricity consumed in the home but released from the power station where it was generated.
It's true to say that no source of energy is totally carbon free, even renewable energy has some carbon cost in the manufacture and maintenance of the equipment.
All fossil fuels contain carbon and hydrogen in different combinations and energy is released when they are burned. The process is a chemical reaction in which oxygen from the air combines with the carbon to create carbon dioxide and with hydrogen to create water vapour. Both are greenhouse gases which enter the atmosphere.
Carbon dioxide is needed for the growth of vegetation but not all of it can be absorbed by plants and the oceans and the remainder continually adds to the concentration already in the atmosphere. These gases are called greenhouse gases because they create a layer in the upper atmosphere that traps heat.
The presence of this layer is natural and maintains the earth's warmth but as its concentration increases the ability of the atmosphere to release excess warmth is impaired and the fear is that the climate will become out of control.
Whenever we waste energy through inefficiency or unnecessary use, we add to the problem for no good reason. We only need part of the energy we consume and whatever we can save means less pollution is produced.
All fossil fuels contain carbon and produce carbon dioxide when burned, but in varying amounts. Gas produces the least compared to the amount of energy produced. LPG produces about 20% more, oil produces 30% more with coal nearly 80% more. Electricity is generated from a mix of different fuels and creates around 100% more than gas.
Renewable energy generation creates significantly less carbon dioxide with wind and hydro power similar to nuclear at about 0.1% of gas, solar PV 6% and biomass 10%.