A UK power station that has received billions of pounds in government subsidies has failed more than once to report it burned wood from primary forests, BBC News has found.

Drax Power Station, which burns wood pellets, is required to report where it sources its wood and whether it is from natural, previously untouched forests.

The company paid a £25m penalty last year for misreporting this data following an investigation by the energy regulator Ofgem and now the BBC has discovered a further year of misreporting that has not been looked at by the regulator.

The company did not deny misreporting its sustainability data but said it is “focused on implementing the lessons learned”.

The power station, a converted coal plant in North Yorkshire, generates approximately 6% of the UK’s electricity and has received billions of pounds in subsidies from the government and bill-payers because wood-burning is classed as a source of renewable energy.

BBC Panorama and BBC News has previously reported that Drax held logging licences in British Columbia, Canada, and used wood, including whole trees, from primary and old-growth forests for its pellets.

These are natural forests that have never been industrially logged and lock up and store significant amounts of carbon as well providing key wildlife habitats.

The company says it does not own forests or sawmills, no longer bids for logging licences and has stopped sourcing wood from some sites, where the British Columbia government has asked companies to pause further logging.

However, public logging records show Drax still sources whole trees from primary forests that are felled by other companies in the province, despite stating in its own sustainability criteria that the company will “avoid damage or disturbance to high carbon forests” which “can be defined as primary forest”.

Modern industrial logging only really began in the interior of British Columbia in the 1960s, which means the areas that have been logged and replanted in recent decades are not yet mature enough for these plantations to harvested.

Nearly all the industrial logging that takes place in the interior of the province is from “woodland of native species where there is no clearly visible indication of human activities and the ecological processes are not significantly disturbed”, the wording used by Ofgem to define primary forests.

Drax was required to report to Ofgem that it had sourced wood from these areas but data obtained by the BBC through environmental information requests shows the company failed to declare any wood from primary forests in the sustainability data it submitted to the regulator regarding its Canadian wood pellets for the year 2020-21.

That year Drax burned just over 1.2 million tonnes of wood pellets from Canada, with a significant proportion coming from primary forests in the interior of British Columbia.

The company did not respond to the BBC’s questions about why it had misreported its sustainability data and whether it had misled both the government and the energy regulator over its use of wood from primary forests.

Drax appears to have since reduced its reliance on Canadian wood. The company said that only around 2.5% of pellets used at its power station in 2023 came from British Columbia, predominantly from public forests that have been designated for harvesting.

The company said it “recognises the importance of sustainably sourced biomass, and we work to ensure our pellets are legally harvested and meet the strict sustainability requirements of the UK, US, and Canadian governments, as well as those of the EU.”

The UK’s current biomass sustainability criteria does not prohibit whole trees from primary forests being used for wood pellets.

The company added that the misreporting previously identified by Ofgem was “technical in nature” and “would not have impacted the levels of ROCs [subsidies] earned”.

According to Ofgem, accurate sustainability data enables the government “to understand and monitor the extent to which both primary forests and sawlogs are used in woody biomass, which has consequences for carbon emissions and biodiversity”.

Following their investigation last year and Drax’s subsequent £25m penalty for misreporting data, the regulator Ofgem said it “won’t hesitate to act” in the event of further wrong-doing.

However, when approached by the BBC the regulator did not commit to any specific action relating to the further misreporting uncovered by the BBC.

In a statement an Ofgem spokesperson said: “We thank the BBC for sharing this information which relates to the same issue that was identified in our investigation into Drax.”

They added that Ofgem is making Drax “conduct a full independent, external audit of its global supply chain profiling data to satisfy us appropriate processes and controls are in place for the future” and added: “If any additional evidence comes to light following the audit, we will investigate again.”

Drax’s current renewable subsidies schemes come to an end in 2027 and the BBC’s discovery of further misreporting of sustainability data by Drax comes as the government is expected to announce an extension of Drax’s subsidies imminently.

The government says it is carefully considering amending the current biomass sustainability criteria and will issue an update shortly but did not confirm whether it will prevent wood from primary forests being used for wood pellets.

A spokesperson for the Department for Energy Security and Net Zero said: “The situation we inherited for large scale biomass generators was unacceptable.

“Ofgem required a further audit to be undertaken and they are working closely with Drax to ensure any misreporting does not happen again.”