Waste to energy: how it works and where it fits in the UK
Waste to energy means burning or breaking down waste that cannot be recycled to produce electricity, heat or gas. In the UK most of it happens in energy from waste plants, which burn general waste to drive a turbine. It ranks above landfill but below recycling.
Waste to energy: key facts
| What it is | Making electricity, heat or gas from waste that cannot be recycled |
|---|---|
| Main method in the UK | Burning general waste in an energy from waste plant |
| Place in the waste hierarchy | Recovery: below recycling, above landfill |
| Metal from the ash | Recovered and recycled. It adds about 0.9 percentage points to the UK recycling rate, according to Defra |
| Carbon pricing | The government plans to bring waste burning into the UK Emissions Trading Scheme from 2028 |
How does an energy from waste plant work?
- Delivery. Lorries tip general waste into a bunker.
- Burning. A crane feeds the waste into a furnace that runs at 850 degrees Celsius or more.
- Steam. The heat boils water, and the steam drives a turbine that generates electricity. Some plants also supply heat to nearby buildings.
- Cleaning. The gases are filtered and treated before they leave the chimney.
- Ash. Metal is pulled from the ash and recycled. The rest is used as aggregate in building.
Other ways to get energy from waste
| Method | Waste used | What it produces |
|---|---|---|
| Anaerobic digestion | Food waste and farm waste | Biogas and a fertiliser |
| Landfill gas capture | Waste already in landfill | Gas that is burned for electricity |
| Gasification and pyrolysis | Sorted general waste, tyres, plastics | Gas or oil |
| Cement kilns | Shredded waste used as fuel | Heat for making cement |
Is waste to energy better than recycling?
No. The waste hierarchy puts recycling above energy recovery, because recycling keeps the material in use and saves more energy than burning releases. Waste to energy is the right place for what is left after recycling. It is better than landfill, which is taxed heavily and produces methane.
What it means for a business
Ask your collector where your general waste goes. Many now send it to energy recovery, which helps a business reach zero waste to landfill. The cheaper and greener step is to take recyclable material out of that bin first. Food waste should go to anaerobic digestion through a separate collection. See our guide to commercial recycling.
Frequently asked questions
What is waste to energy?
It is the use of waste that cannot be recycled to produce electricity, heat or gas, usually by burning it in an energy from waste plant.
Is waste to energy the same as incineration?
An energy from waste plant is an incinerator that captures the heat to generate electricity. Older incinerators burned waste without recovering energy.
Is waste to energy good for the environment?
It is better than landfill, because it recovers energy and avoids methane. It is worse than recycling, and burning plastic releases carbon dioxide.
What happens to the ash?
Metal is recovered from the ash and recycled. Most of the remaining ash is processed into aggregate for roads and construction.
What is anaerobic digestion?
A process in which microbes break down food and farm waste without oxygen. It produces biogas for energy and a liquid used as fertiliser.