Recovering energy from our waste
Residual waste is any waste material that cannot be viably recycled. However, although this material cannot be recycled, it does represent an important source of energy.
There are several processes that can be used to recover energy from residual waste, such as incineration in specialist energy from waste plants, methanation or the production of Solid Recovered Fuel (SRF) which converts the waste into solid fuel to replace coal used inenergy-intensive industries, such as cement works.
In 1988, SUEZ won its first waste management contract in the UK. At this time, the country produced 400 million tonnes of waste a year, most of it ending up as landfill. To comply with EU directives, the UK started recovering energy from its waste instead. Today, SUEZ provides solutions and services to almost 12 million people and treats over 9 million tonnes of household, commercial and industrial waste.
In 2013, West London Waste Authority signed a 25-year Public-Private Partnership (PPP) for the recovery of residual waste into energy. The consortium, led by SUEZ in partnership with Scottish Widows Investment Partners and ITOCHU Corporation, designed, financed and built the waste-to-energy plant and will now operate the facility, with a process capacity of 300,000 tonnes of waste a year.
The residual waste produced by 1.6 million inhabitants of West London will now be transported by rail to the new Severnside Energy Recovery Centre (SERC). The 34 MW facility will produce electricity to power the equivalent of 50,000 households and could also provide hot water to local businesses. The plant will enable 96% of waste to be diverted from landfill for recovery.
In 2014, SUEZ and its Sembcorp Utilities UK and ITOCHU Corporation partners signed a 30-year PPP contract with Merseyside Waste Disposal Authority (MWDA).
The consortium financed, built and will now operate the new facility, which will recover over 430,000 tons of residual household waste a year into energy for the equivalent of 63,000 households. The facility is also capable of providing heat to local businesses and factories.
Residual waste will be collected and transported by rail to a new transfer station, before being taken to the 49-megawatt waste-to-energy facility at Wilton International industrial estate at Teesside.
The solution will enable 92% of residual waste to be diverted from landfill and will also reduce CO2 production by approximately 130,000 tons a year compared with landfill disposal. The use of rail transport replaces the equivalent of 21,000 days of road transport a year.
 This figure only includes the energy produced by EfW plants and not the part coming from Solid Recovered Fuel (SRF) and biogas.
 These processes produce both heat and electricity at the same time.