The lower house of the Polish parliament, the Sejm, has reduced the minimum distance required for new onshore wind projects to 700 metres from homes in a move the nation's wind industry slammed as next to useless.

The amendment to a highly damaging law dating from 2016 reduces the minimum distance from a previously enforced 10 times the turbine's tip height, which often meant 2,000 metres or more, meeting a long-held demand of the industry.

But lawmakers at the last minute changed the level to 700 metres from 500 metres previously planned by the government, which the Polish wind energy association (PWEA) condemned as a grave mistake.