ECO4 scoring methodology

This page contains the ECO4 Partial Project Scores Matrix and the ECO4 Full Project Scores Matrix.  

Each measure or package of measures installed under ECO4 receives a score which determines the contribution that the measure makes towards a supplier’s Home Heating Cost Reduction Obligation (HHCRO) obligation. Scores are based on the annual cost saving achieved by a measure or package of measures when installed in an eligible domestic premises.

Full project scores (FPS) are awarded in respect of packages of measures where the relevant minimum required SAP band improvement is met. FPS are based on the difference in expected annual energy costs between the starting and finishing intermediate SAP band, and the floor area of the premises.

Partial project scores (PPS) will be awarded as each measure within a project is notified and approved. These are interim scores which represent a proportion of the bill saving improvement of the measure. In most cases, once the project meets the relevant minimum requirement, the PPS will be replaced by FPS.

PPS for measures other than infill measures are subject to a 20% deflator (reduction). The deflator has not been applied to the PPS in the matrix. It is applied by the ECO4 Register when a measure is notified to us.

In certain circumstances, ‘uplifts’ or ‘increases’ may be applied to the cost savings which increase the value when determining a score. Increases (for heating repair and replacement and building fabric repair) are included in the PPS matrix. Uplifts are applied by the ECO4 Register and are not included in either matrix.

Full guidance on the partial project scores and full project scores can be found in Chapter 6 of the ECO4 Delivery guidance.

Further information on the development of the partial project scores and full project scores is published on our ECO4 scoring consultation decision page.

If you have a query about the scores or their use, you can contact us at eco@ofgem.gov.uk.

ECO4 full project scores matrix - version information

Full project scores matrix version 2 – published 13 June 2022

• The full project scores matrix originally published on 11 May 2022 was updated due to legislative requirements. Projects with a post-project SAP rating of Low A or High A are to be treated as High B. Therefore, full project scores with a post project rating of Low A and High A have been reduced to equal the corresponding full project scores with a post project rating of high B.

ECO4 partial project scores matrix - version information

Partial project scores matrix version 2 – published 25 October 2022

Three sets of scores/score variants have been added:

• Scores for the insulation of park homes (PHI).
• Boiler upgrade scores with room heater pre-main heat sources.
• First time central heating scores with the electric storage heater pre-main heat source.

Corrections have been made to some heat source and measure category names.

• Post-main heat source ‘mCHP’ corrected to ‘Fuel Cell mCHP’.
• Post-main heat source ‘Shared ground loop GSHP’ corrected to ‘Shared Ground Loop GSHP’.
• Pre and Post-main heat sources ‘DHS_CHP’ and ‘DHS_non-CHP’ corrected to ‘DHS CHP’ and ‘DHS non-CHP’ respectively.
• Measure category ‘Uplift’ corrected to ‘Fixed Value Increase’

Partial project scores matrix version 1 – published 13 June 2022

The partial project scores matrix was largely complete, however scores for specific measure types were still to be added:

• Park home insulation scores were still under development.
• Boiler upgrade measures: we reintroduced separate scores for the installation of boiler upgrade measures in homes with and without pre-existing heating controls. Both sets of scores are included in this version of the matrix, however the scores for homes with pre-existing heating controls are preliminary versions. The preliminary scores are the minimum that will be awarded for these measures: we have taken a cautious approach in creating them, such that any revision will be upwards.