Ofgem published its decision on parts 1 and 2 of the ECO4 scoring methodology consultation on 12 April 2022, setting out its final position after two consultations held in 2021. The document summarises responses to both consultations and explains where suggestions could not be incorporated1.
The regulator confirmed that full project scores will be based on starting and finishing intermediate SAP bands, and that scores will be segregated into the four floor area segments set out in the consultation. Pre-calculated, deemed partial project scores will be based on floor area and intermediate SAP band, and the final set of partial project scores includes a correction factor of 10%1.
"We will retain our proposed approach and remove the wall type distinction for heating measures."
Other decisions in the document include splitting the standard heating control measure, removing the pre-main heat source for insulation measures, and introducing partial project scores for new district heating system connections in ECO4. Ofgem said it has decided to postpone its decision on one matter until further information on guidance is available1.
The document states that scheme rules will require the partial project score for a measure to represent its average annual energy bill savings, based on the difference in average annual bill expenditure between the starting and finishing SAP ratings of the property. Ofgem said its understanding is that ECO4 legislation will instruct it to calculate scores with reference to SAP 2012, while thresholds will continue to be expressed to one decimal place1.
On related policy, Ofgem noted that BEIS published the Government Response to the consultation on 1 April 2022, and that BEIS decided not to take forward a proposal to make the English Boiler Plus standard a specific ECO requirement throughout Great Britain. A complete edition of SAP 10 (SAP 10.2) was published in February 2022 and is expected to be adopted for Building Regulations purposes in England from June 20221.
| Item | Decision |
|---|---|
| Full project scores | Based on starting and finishing intermediate SAP bands |
| Floor area | Four segments, as consulted |
| Partial project scores | Pre-calculated, deemed, based on floor area and intermediate SAP band |
| Correction factor | 10% |
| Heating measures | Wall type distinction removed |
| Heating controls | Standard heating control measure split |
| Insulation measures | Pre-main heat source removed |
Why it matters for households
The Energy Company Obligation is a government scheme requiring obligated energy companies to deliver energy efficiency measures to domestic premises in Great Britain. It is administered by Ofgem, while policy and legislation are set by the Department for Business, Energy and Industrial Strategy1.
The scoring methodology determines how much credit a supplier receives for a measure installed in a home, which shapes which properties and which measures suppliers are willing to fund. The use of intermediate SAP bands and floor area segments means the score attached to a measure depends on the property's starting energy performance and its size, rather than a single flat value. The 10% correction factor accounts for interaction between measures installed in the same property1.
For a household, the practical effect is that the attractiveness of a property to a supplier under ECO4 depends on its assessed starting SAP rating and floor area, and on which measures are proposed. The document does not set out eligibility rules for individual households, which sit with the scheme's legislation rather than the scoring methodology1.
What happens next
ECO3 ran from 3 December 2018 to 31 March 2022, and ECO4 is intended to run from 2022 to 2026. An interim delivery period allows suppliers to continue delivering measures to ECO3 rules from 1 April 2022 to 30 June 2022, with some exceptions1. The document does not state a date for the remaining decisions it postponed1.