RIIO Mid-Period Review (RIIO T1 and GD1)

The RIIO final proposals included a provision for a potential Mid Period Review (MPR) of network company output requirements under the eight year period of the RIIO-T1 and GD1 price controls.

When we developed the RIIO price controls we recognised that there were potential uncertainties that could affect the outputs companies would need to deliver and the expenditure requirements to deliver them. We also acknowledged, given the shift from a five year to an eight year price control period, the potential uncertainties could be greater. So to address this and to ensure the companies continue to deliver the outputs consumers will benefit from, various types of uncertainty mechanisms were included in the RIIO model, including a review of outputs half way through the price control – the Mid-Period Review (MPR). 

Here you can view and download documentation on the RIIO-T1 and RIIO-GD1 MPR process.

For information on working groups held as part of the MPR including agendas, actions and key presentations, please see the RIIO-T1 and GD1 Mid-Period Review forum.

The MPR process

We set out in Final Proposals a proposed three-phase process for any MPR.

Phase 1

We consult and set out any potential issues that may be relevant for initiating an MPR.

Phase 2

If an MPR is found to be needed, we would assess and develop any proposed changes in Phase 2.

Phase 3

We would consult on any proposed changes and make any necessary amendments to the licence to implement these during Phase 3.   

Publications and updates

  • Published: 4th Aug 2017
  • Decisions
  • 3 Associated documents
Decision to modify the RIIO-T1 and RIIO GD1 PCFMs to account for the LMP refund and the National Grid voluntary deferral.

  • Published: 4th Jul 2017
  • Closed: 1st Aug 2017
  • Consultations and responses
  • 9 Associated documents
We are consulting on changes to PCFMs accounting for two recent decisions (National Grid allowance deferrals and Cadent refund for medium pressure iron mains

  • Published: 4th Jul 2017
  • Decisions
  • 14 Associated documents
We made our MPR parallel work decision, which considered several transmission and gas distribution price control issues.

  • Published: 17th May 2017
  • Charts and data, Decisions
  • 3 Associated documents
The decision on modifications to the RIIO-ET1 and RIIO-GT1 PCFMs to incorporate the mid-period review.

  • Published: 22nd Mar 2017
  • Closed: 21st Apr 2017
  • Consultations and responses
  • 8 Associated documents
The Statutory Consultation on modifications to the RIIO-ET1 & RIIO-GT1 PCFMs to incorporate the mid-period review.

  • Published: 24th Feb 2017
  • Closed: 21st Apr 2017
  • Consultations and responses
  • 9 Associated documents
MPR parallel work takes a look at several areas in our transmission and gas distribution price controls. Our consultation document sets out our proposed approach.

  • Published: 24th Feb 2017
  • Decisions
  • 4 Associated documents
From our mid-period review for RIIO-T1, we have decided to reduce National Grid’s allowances across gas and electricity by £185m.

  • Published: 18th Aug 2016
  • Closed: 6th Oct 2016
  • Consultations and responses
  • 13 Associated documents
We are consulting on our proposals for changes to RIIO-T1 outputs and allowances as part of the mid-period review (MPR) for electricity transmission and gas transmission.

  • Published: 12th May 2016
  • Decisions
  • 1 Associated documents
We have decided to launch an MPR for RIIO-T1 looking at specific issues in Electricity Transmission and Gas Transmission for NGET and NGGT. We have not identified any MPR issues for the Scottish TOs. We have decided not to launch an MPR for RIIO-GD1.

  • Published: 12th Nov 2015
  • Closed: 12th Jan 2016
  • Consultations and responses
  • 11 Associated documents
We are consulting on whether there is a need to initiate an MPR in Electricity Transmission and Gas Transmission, and Gas Distribution.