Energy from waste facilities must utilise their heat potential to maximise efficiency and carbon dioxide emissions savings, says Energos MD.
Speaking at The Waste to Energy City Summit, held in London on 21 June 2012, Energos MD Nick Dawber told the audience that EfW plants should exist within the heart of industrial and residential communities to utilise the heat value of the waste instead of wasting this renewable, low cost energy resource.
He said: “To achieve higher levels of efficiency we need to sell heat - either directly as steam to industrial customers to displace existing fossil fuel supplies - or as combined heat and power (CHP).
“When the ratio of energy used is two parts heat to one part electricity, facilities will achieve up to 50 per cent efficiency, which rises to as much as 85 per cent if you utilise the full heat potential.”
He explained that it is necessary to develop smaller efw plants to capitalise on heat potential since there are more available sites for small facilities, which can be located close to the potential demand for heat and are appropriately sized to satisfy that heat requirement.
He also said that there will be higher public acceptance for ‘community sized’ facilities.
Smaller plants minimise traffic to the site and can sit alongside recycling facilities to provide a local solution for local non-recyclable waste while delivering a renewable supply of low carbon, low cost energy.
He called on the government to accelerate the development of district heat networks, as demanded under the EU Energy Efficiency Directive, to avoid valuable heat resources being wasted.
He stated that a large 400,000 tonnes per annum efw plant, producing around 32 MW of electricity, would have a surplus of around 70 MW of heat that is normally lost to the atmosphere because there are very few industrial facilities that have sufficient CHP demands for large-scale EfW.
Dawber stated: “Small-scale facilities such as Energos’ facilities in Norway and its UK sites, scheduled to open in 2014, can supply usable amounts of energy (up to 20 MW of heat) to local customers.
“Apart from the efficiency benefits, such plants also qualify as a ‘recovery’ plant under the EU Waste Framework Directive and stand to benefit from the UK’s Renewable Heat Obligation.”