The decision has been made to move from a gasification technology, to a conventional grate technology.
This technology is widely established and proven. It is used in ~90% of the UK’s 48 fully operating energy from waste (“EFW”) facilities and in over 400 EFW facilities across Europe. This will necessitate a new planning application / permission.
There are three primary reasons why the technology for the project is being changed.
In the latter in part of 2019, new standards were introduced, driven by European legislation requiring reductions emissions limits from industrial facilities such as energy from waste. These standards are derived from the “Best Available Techniques Reference Document” or BREF and means that conventional moving grate combustion technology must now be built to achieve the predicted performance of gasification technologies. As a result, the more challenging to deliver gasification option offered no advantages on emissions under these new standards when compared to tried and tested combustion technologies.
The investment decision in September 2019, influenced largely by the uncertainties with BREXIT at the time, shifted away from gasification technologies with less stable supply chains which could no longer offer competitive solutions or guarantee build times required for this £200m investment. The supply chains for a tried and tested conventional moving grate combustion technology are more established, and better able to offer competitive solutions whilst guaranteeing build times in a post-BREXIT UK. Therefore, it was not just technology type, but the deliverability that influenced the investment decision.
During development of the project, there has been an increased focus and effort on removing certain materials from waste streams, which NREL supports, with plastics being a recent example. Conventional moving grate combustion technology offers more flexibility with predictable performance to adapt to these changes in residual waste whilst generating low carbon energy.