I think that now is a good time to take a fresh look at the role of waste to energy (WtE) in the UK; but perhaps not at the large scale that it has been used before. Smaller WtE project with Combined Heat and Power (CHP) are still quite large compared to most CHP systems. They sit between packaged CHP systems with limited fuel choices and large municipal WtE projects, which can take years to get through planning. My suggestion is that they have some distinct advantages over both, but they get relatively little in the way of government support.
There are some good examples of CHP WtE projects in the UK, which have heat and power outputs of about 10-20 MW. This is a size range that can usefully be deployed on an industrial site or mixed use development, but would be too small by municipal standards. One possible application is to tap into the potential for heat and power from waste, by colocation; building the projects next to (and ideally, at the same time as) the energy users. A waste to energy plant integrated into an industrial estate ensures that there is a ready use for heat and power as well as a disposal route for site waste. These projects are interesting because if they use well established, robust technology so they can accept a wide variety of fuels, which greatly reduces the risk of fuel price variation, but the technology can be expensive. To be clear; I am not suggesting wider use of gasification in these projects. There have been some gasification projects making headlines in recent months and it’s fair to say that subsidies for gasification have encouraged some interesting new technologies into the market. It remains to be seen whether those technologies are robust, or whether that subsidy will deliver long-term value.
The potential role of ‘tactical’ CHP WtE projects is important, at a time when the UK government is struggling to meet its targets for renewable heat. Although we have made good progress in renewable electricity generation in the UK, we are less than halfway towards the target of 12% of heat from renewable sources, according to the Energy and Climate Change Committee. This is in spite of the increased emphasis on renewable heat and the introduction of the Renewable Heat Incentive (RHI) and Contracts for Difference (CfD.)
Within the current tariff arrangements, the income to a CHP WtE project is a combination of gate fee (the fee paid by a waste producer, to the waste disposer) and heat and power sales, unless they burn biomass. The benefit from the current CfD strike prices for CHP WtE projects is marginal at best. What would make these projects much more attractive, is a tariff structure (from the RHI or CfD) aimed less at promoting gasification technology and more about enabling those CHP WtE projects that are already on the cusp of viability.
It seems like too good an opportunity to waste.