Can a pond harness solar energy?

Solar Pond

  Solvay mines and quarries in Escuzar, next to Granada in Spain : ore extraction site - settling pond
Solar Pond is a major step towards the use of renewable energies in the European industry. Our technology uses a saltwater pond to capture solar energy and store it for conversion into thermal energy, which can be used to heat buildings, industrial water, or power engines to generate electricity.

How it works
By setting up a vertical salinity gradient, with high salt concentration at the bottom layer, it is possible to create a non-convective zone inside the pond, which is in the base of the pond heat storage capacity. The system can reach temperatures of over 80°C at the bottom and can trap the heat for quite a long time, forming a kind of natural energy storage. 

Solvay uses an interchanger to convert the heat and replace the use of conventional boilers run using diesel fuel. By doing so, we reduce energy consumption and costs, promote waste management, and decrease CO2 emissions.

“We’ve seen that Solar Pond thermal energy can divide by two the amount of gasoil consumed at a plant, and that plants using this technology could recover their investment in just four years’ time, thanks to those significant gasoil savings,” says Carlos Aladjem, Regional Expertise South EU Manager, Solvay Energy Services. 

The Solar Pond project team – which is comprised of Solvay Iberica, Universitat Politecnica de Catalunya (UPC), and Royal Melbourne Institute of Technology (RMIT) University, and is sponsored by Luis Serrano, Regional Manager of Solvay Iberica – is now building a 500 m2 pre-industrial scale solar pond at the GBU Special Chemicals site in central Escúzar, Granada, Spain. The Escúzar Pond Solar pond will be the first built in Europe, and will serve as a role model for the use of renewable energy.