I’ve long been a fan of solar powered desalination, and have written about it several times on this blog. It offers the best hope of expanding and intensifying food production to feed a growing global population, and so simultaneously to leave more space for biodiversity to regenerate. So far all the solar desalination projects had been relatively small scale pilot facilities, designed to prove that the technology worked. It did. The challenge then was to build full-scale food production systems in the hot dry deserts of the world. The first such project has just opened.
Last week Sundrop Farms officially opened their newly enlarged facility at Port Augusta in South Australia. They have expanded 100 fold, from 2,000 square metre pilot to 20 hectare commercial scale greenhouses, which now are in full production, growing 15,000 tonnes of tomatoes per year in what was unproductive desert. Mirrors focus the solar energy onto a power tower which can generate up to 35MWt steam, 50% of which is used to heat the greenhouses, 30 – 35% is used to desalinate seawater and the remaining 15 – 20% is used to generate electricity. They get about 320 sunshine days per year, and have on-site heat and water storage to cover for days when the sun doesn’t shine, and also have grid connection for added security. There is a 16 minute video which really gives a good feel of the place and what they’ve achieved.
Sundrop developed from an original idea developed by Charlie Paton, which he called a Seawater Greenhouse. He developed many of the pilot projects. Now he is developing a new lower cost pilot project in Somaliland, utilizing cheap shade netting instead of expensive greenhouses, but still using his original solar and wind powered desalination techniques. He is working with Gollis University in Somaliland and Aston University and DFID in UK.
The Sahara Forest Project is another thing that Charlie Paton originated which has now spun out into a Norwegian based company seeking to develop a number of related ideas and technologies. In 2012 they built a pilot in Qatar. Now they are researching doing a project in Tunisia.
Together all these developments suggest possibilities of more sustainable, and more intensive, food production in the worlds hot dry deserts.