The National Audit Office (NAO) has branded the Renewable Heat Incentive (RHI) as not achieving “value for money”.

In its report into the incentive, the auditor said that the Department for Business, Energy & Industrial Strategy (BEIS) “does not have a reliable estimate of the amount it has overpaid to participants that have not complied with the regulations, nor the impact of participants gaming them, which could accumulate to reduce the scheme’s value significantly”.

Ofgem has suggested 4.4% of non-domestic schemes did not comply during 2016-17, with an estimated £3 million over-paid to RHI participants.

The NAO calculated that total payments between November 2011 and August 2017 reached £1.4 billion, and it is expected that outgoings to new participants could reach £23bn by 2040-41.

Only 22% uptake

The NAO also warned that take-up of the scheme had been much lower than had been forecast, with fewer than 80,000 biomass boilers and other renewable heat sources having been installed by December 2017.

The audit watchdog estimates that some 110,000 systems will have been installed by March 2021.

Yet that will only be 22% of the original prediction of 513,000 installations by 2020.

> Download the report