With the current consultation ongoing with regard to the Renewable Heat Incentive there is currently renewed interest in the supply of heat as well as electricity from facilities that extract energy from waste. For traditional energy-from-waste plants, heat supply is also an essential to have the opportunity to qualify for Renewable Obligation Credits (ROCs) for the electrical output derived from renewable sources.
The RHI and ROC incentives should, if correctly implemented and incentivised, make the supply of heat more commercially possible
We must not forget that it is also the most sustainable solution and one that we all therefore strive to achieve where practically and economically feasible. The RHI and ROC incentives should, if correctly implemented and incentivised, make the supply of heat more commercially possible. At Sita UK, we have endeavoured to try find outlets for heat for all of our energy recovery plants either by locating the facility near existing heat users or grid networks or, by co- locating with new developments which are built with heat supply in mind or by attracting heat users to develop near an existing plant or one that is proposed.
The use of heat, either as a primary output or a secondary output from energy recovery plants fuelled by waste has been a goal for many years in the UK but generally has failed to materialise. In Europe, it is the exception and not rule to supply heat. For instance, in Germany over 80% of the EFW/RDF to energy plants export heat either as a primary or secondary output. In excess of 44 plants supply electricity and heat, nine plants supply heat as steam and two supply heat to district heating schemes.
While electricity networks are almost everywhere and gas grids reach the majority of homes and business across the country, heat is more difficult to supply because our community infrastructure lacks a heat network. This hurdle is one that has often been insurmountable even through the original Non-fossil fuel obligation (NFFO) incentive schemes which included heat and were designed to encourage commercial supply. In the majority these did not achieve their goal. Although it could be argued that the incentives were too low, the answer is probably more complex than that. Low primary energy prices historically meant there was little incentive on heat users to adopt a different method of supply and thus although there was a push from Government to supply heat there was not the same pull from users to want to be connected.
So what’s different now? Well not only does it appear that we have or will have incentives to supply but also energy security, increased energy cost and the cost of carbon through the various carbon mechanisms are providing a desire for heat from users and thus a commercial reason to be connected exists.
There are a number of schemes currently trying to move forward for the industrial scale supply of heat to traditional large industrial users such as is proposed for our Cornwall Energy Recovery Centre (CERC). However, there is also a small revolution going on for the small, community scale plants such as some of the plants being developed by our partner Cyclamax, where the whole concept of the plant is about an integrated energy centre for the local area.
Working with industrial customers for on-site industrial solutions or developers and development agencies for new projects will help maximise the opportunity for heat supply through having heat supply in mind at the start of the development when infrastructure costs and local disturbance are minimised. This will avoid the need to retrofit heat supply pipes and mains through existing roads and infrastructure with the associated disturbance and increased cost. Grid capital cost is especially important for small scale schemes where large supply infrastructure capital burdens will often overwhelm any supply incentive influence in the economics.
Stuart Hayward-Higham is technical director at Sita UK