Breaking through the 50MW barrier - finding a sensible way to authorise higher output from existing power stations

It's an issue a number of power stations are facing, particularly energy from waste plants. They have planning permission for a sub-50MW plant, but through technological improvements and efficiencies they find they can now potentially export more than that. It should be a good news story: no increased input (no more waste being trucked to the site or burnt) but more electricity output. But there's a catch – the wording of section 15 of the Planning Act 2008 - which requires the "construction or extension of a generating station" to be authorised by a development consent order (DCO) if it's over 50MW.

Project developers in this situation are therefore wrestling with whether they need a whole new consent (a DCO) to "construct" their project, or to "extend" it. Wheelabrator's approach at Kemsley was to re-consent the "construction" of the power station they had planning permission for and were in the process of building. By the time the DCO was granted, the power station was in fact already operating, but with its output limited down to the 50MW threshold ending grant of the DCO. The Kemsley DCO notionally authorises the construction of the already built plant, as well as its operation up to 75MW, but the conditions in the DCO (known as "requirements") only control the operational phase given the reality on the ground that the plant has already been built (see here). The South Humber project has recently adopted a similar approach although in that case construction had not started at the time of the DCO examination (see here).

There is something odd about re-consenting physical development which has already been consented (via a planning permission) and perhaps already been built. Looking at meeting notes of early meetings between Wheelabrator and the Planning Inspectorate, the impetus for this approach seems to have been concern that there must be an act of "development" to pin the capacity increase to. This is clearly true, given the wording of the Planning Act 2008 – see Michael Humphries QC's excellent explanation in Article 13 of Francis Taylor Buildings' "National Infrastructure Planning Handbook".

However, in our view it makes more sense to pin it to the internal "engineering operations" which enable the power increase, rather than to re-consent the whole plant. As every planning lawyer knows "engineering operations" count as "development" (Fayrewood Fish Farms Ltd v Secretary of State for the Environment and Hampshire County Council [1984] JPL 267). Doing it this way avoids the oddity of: (1) justifying the need for infrastructure that has already been consented/constructed; and (2) putting forward an environmental impact assessment setting out the impacts of construction that may have already happened.

The promoters of the Slough Multifuel Project recently submitted a scoping report to PINS adopting the "engineering operation" approach (see here), which has not been challenged by the Planning Inspectorate, who recently granted a scoping opinion for the project (see here). This should set a useful precedent for other projects. Even better would be if the Department for Business Energy and Industrial Strategy (BEIS) or the Planning Inspectorate brought out some guidance endorsing this approach.

It's one thing to use a DCO to re-consent construction of a power station not yet constructed, or one which is in the process of being constructed. But this legal device feels more awkward if we imagine a power station which may have been built and operating for many years before technology presents the opportunity to break through the 50MW barrier. In our view, the Slough Multifuel approach, which we assisted in developing, provides the route through which is needed.

We are advising several developers on consenting power upgrades. Please do get in touch if you would like to discuss this issue.

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