By Susanna Twidale

LONDON (Reuters) – Britain’s energy regulator Ofgem said on Thursday power firm Drax misreported some data about biomass imported from Canada and would pay 25 million pounds ($33 million) to Ofgem’s voluntary redress fund.

Drax, Britain’s largest renewable power generator by output, has converted four coal-power units to use biomass and operates hydro power projects.

The investigation found Drax did not have adequate data governance controls on biomass imported from Canada during the period from April 1 2021 to March 31 2022 but said it had not found any evidence the biomass did not meet its sustainability requirements.

In Britain renewable power generators can receive renewable obligation certificates which can then be sold to energy suppliers who use them to sell renewable electricity products to customers.

“The investigation found that the misreported data was technical in nature and would not have impacted the level of subsidy Drax received under the RO (renewable obligation) scheme,” Ofgem said.

Drax said it would resubmit its Canadian data for the period and produce an independent audit of its biomass profiling data for the most recent reporting period, April 2023 to March 2024.

“We recognise the importance of maintaining a strong evidence base and are continuing to invest to improve confidence in our future reporting,” Drax Group CEO Will Gardiner said in a separate statement.

Drax says it only uses wood residuals or byproducts from trees primarily used for lumber and that demand for wood from sustainable managed forests can help to increase forest growth.

Green groups have criticised the practice, arguing that it is not a renewable form of energy generation and that pellet production can contribute to deforestation.

Ofgem’s redress fund is used to help charities support vulnerable energy customers.

($1 = 0.7565 pounds)

(Reporting by Susanna Twidale in London and Yamini Kalia in Bengaluru; Editing by Mark Potter)