A minor change to wording incorporated within the Department of Energy and Climate Change’s RO consultation response could mean as much as 1GW of ground-mount solar could fail to qualify for the 1.3 ROC grace period, which closes on 31 March 2016.

Wording within the response has changed the planning requirement from ‘received’ to ‘validated’, meaning that if a project is to qualify for the grace period developers must have received notice from the local planning authority in question confirming that planning documents were both received and considered valid.

The consultation response cites evidence that was allegedly forthcoming during the process which showed a number of invalid or incomplete planning applications being made on 22 July following the announcement of the plans. It suggests that some developers looked to rush applications through to LPAs in order to comply with the grace period requirements.

“The government has therefore been decided to clarify that the requirement is for evidence of a valid planning application as set out in planning legislation across Great Britain,” the response states.

Developers hoping to qualify for grace will be expected to show a letter or email from the local planning authority confirming that the application was both received and validated.

While this will indeed weed out any plans which were submitted incomplete, it will also catch a large number of genuine applications. Furthermore, and given the time requirements for planning applications to be validated by LPAs, it is now highly likely that a legal challenge could target the consultation as being retroactive in its nature.

Writing for Solar Power Portal in a blog post explaining the situation today, Solar Intelligence’s Finlay Colville said: “If you follow the letter of the law only for a change in legislation to come out after the event that then alters the legal framework you were working under in the past, it is a retroactive policy adjustment.”

While Colville has argued that this could simply be a misstep from DECC, he also noted that it could mean that up to 1GW of ground-mounted solar that might otherwise have qualified for grace will now not.

“If the change of wording for grace-compliancy wasn’t intended by DECC, then surely DECC needs to correct this ASAP. If it was a means of creating even more investor uncertainty in solar, then the timing of the announcement before parliamentary recess could be considered job-done,” Colville added.

DECC had yet to respond to requests for comment at the time of publication.