Two stories about water caught my attention this week – how an ancient technology is helping to cool a Spanish city, and how abandoned coal pits and stone quarries are increasingly popular in Europe as a site for ‘floatovoltaics’ – floating solar panels.

I have been interested in ‘floatovoltaics’ since I read about the plans to install solar panels on two wastewater treatment plants in Healdsburg, California, in November 2021. At the time, it was thought to be the largest such installation in North America. Researching further, I discovered that Asia was far, far ahead of North America, although it wasn’t easy to find an authoritative overall source for such an emerging technology.

Now it has really caught on in Europe, and governments, businesses and utilities are “scouring out-of-use industrial areas for available bodies of water,” says a recent Bloomberg story. “At the top of the list are ponds and lakes that don’t attract many visitors, and which have steady water levels that won’t disappear beneath snow pack in winter.”