More than 1300 schools have put their hands up for airconditioning under the Cooler Classrooms program, but almost a year after the first round of recipients was announced, just 27 have so far received it.

Work has begun at another 23 schools under the five-year, $500 million project, according to figures from the NSW Department of Education. But the NSW opposition argued that at this rate, the airconditioning rollout would take decades.

Some 1300 schools have put up their hand for air conditioning, and 27 have received it. Credit:Quentin Jones

The figures came as a climate expert warned the department was in a race against time to deliver airconditioning, with temperatures across Sydney increasing and each extra degree of heat reducing learning capacity by two per cent.

Some 900 schools were approved for airconditioning in the first round of applications last November. Another 447 schools applied in the second round earlier this year, but those applications have yet to be approved.