Guide

Reduce your business waste to save money

Recovering energy and producing fuel from waste

You may be able to use your waste to recover energy or produce biofuel.

Recovering energy from waste

You can treat waste using thermal and non-thermal technology to reduce the amount of waste sent to landfill and produce heat, gas or electricity.

Energy-from-waste processes may produce waste by-products that need to be disposed of at landfill, such as ash or digestate.

The main technologies for producing energy-from-waste are:

  • anaerobic digestion
  • gasification
  • pyrolysis
  • incineration

Anaerobic digestion

Anaerobic digestion can produce energy on a small scale. It uses bacteria to break down organic matter without oxygen in specially made digesters - see treating and composting biodegradable waste.

Gasification

Gasification involves heating organic waste with a reduced amount of oxygen and/or steam. It produces a synthetic gas, known as syngas, which can be burned independently in a boiler, engine or gas turbine to produce electricity.

Pyrolysis

Pyrolysis is carried out in the total absence of oxygen. It also produces an energy-rich gas and solid residue. These can then be burned separately to produce electricity. In some pyrolysis processes, the gases are condensed into a liquid fuel.

Incinerating your waste

Incineration involves burning organic material such as waste to produce electricity and heat. Conventional waste incineration plants use the heat produced to generate electricity using a steam turbine. In some cases it is also possible to use the left-over heat. The government is encouraging the development of such combined heat and power (CHP) plants which may be able to provide your business with a source of heat, where the necessary transmission infrastructure exists or can be installed at reasonable cost.

Other ways of recovering energy from waste include recovering methane and mechanical or biological treatment.

Some landfill sites recover methane which is produced naturally when biological waste breaks down in the absence of oxygen. It can be used to generate energy. Methane is a potent greenhouse gas and contributes towards climate change if it is not captured.

Mechanical and biological treatment composting units can also produce solid recovered fuel. There are concerns over the toxicity of burning solid recovered fuel, which the government is trying to address.

Producing biodiesel

You may be able to use waste to produce biofuel as an alternative to non-renewable fuels used for transport.