An Australian company, Infratech Industries has built a field of solar panels on top of a wastewater pond in Jamestown, South Australia.Infratech Industries has built a field of solar panels on top of a wastewater pond in Jamestown. Source: ABC news, Image credit: Mike Sexton

It is said to be among the first of its type in the country, and cost AUD$12 million ($9.6 million) to build. Director at Infratech Industries, Felicia Whiting, says the water cools the panels, making them more efficient.

"Solar panels don't really operate when they're at a high temperature, so we get a longevity of the panels and also the solar rafts can shade the water," Whiting says. "We actually get a cooling of the water which is beneficial for water treatment. We can get about 57% more efficiency than a land-based solar system."

The solar field also boosted water conservation by preventing evaporation and blue-green algae outbreaks, according to Whiting.

"For a one megawatt plant, that's about 70,000 kiloliters a year. That's a big saving and it's also a source of revenue for any host water utility to save that water and on-sell it."

The company plans to expand the technology to another pond in the treatment plant.