The number of companies buying green energy has hit new levels as renewable energy becomes more affordable.

Bloomberg New Energy Finance found corporations purchased a record 5.4 gigawatts of renewable energy to power their operations in 2017, up more than a fifth from the previous record of 4.4 gigawatts in 2015.

It was also a record year for the Asia Pacific region, with about 1.3 gigawatts of clean energy purchased.

Australia ranked fifth globally for renewable investments, with the country’s market valued at $US6.84 billion ($8.54 billion), according to Inframation Deals data.

“In Australia, where corporations signed power purchase agreements for over 400 megawatts in 2017, expensive wholesale power and the availability of renewable energy certificates have increased the economic incentive for locking into relatively cheap renewable electricity prices long-term,” BNEF said.