Solar power could transform food industry in hot countries

Projects are underway to explore solar power’s large scale commercial and domestic potential to heat and chill food in developing countries, according to a leading figure behind the research.

Dr Christopher Sansom, concentrated solar power team leader and senior lecturer in ultra-precision engineering at Cranfield University in Bedfordshire, told FoodManufacture.co.uk forms of solar power had massive potential in hot countries.

He had been involved initially in looking at the domestic potential of solar power in countries such as Africa, Asia, India, Pakistan and South America.

“We were looking for countries that have high direct sunlight and remote communities that have no way of cooking food.”

More well-known photovoltaic (PV) solar power converted the energy from the sun’s rays into electricity, he said. But other solar thermal initiatives he had been involved with used parabolic mirrors to focus the sun’s heat, which could then be used immediately to cook food or stored for later use.

Easier to store heat

One major advantage of the system over PV systems was that it was much easier to store heat than electricity, for hours or days if necessary, said Sansom.

“With the amount of energy from hot countries you can build a nice cooker to fry food that can get up to 200⁰C with a few mirrors.

“We have a number of people working at the moment on trying to design a community level system … we are looking at scaling up from domestic to community to industrial.

“To start with, the technology could be used to create heat to dry crops, tea or coffee – any food that requires drying processes, for which you need temperatures of up to 100⁰C.”

Store crops

This would enable indigenous communities to store crops over longer periods, rather than having to sell them right away, helping them to achieve better prices, he said.

However, as methods developed, any industrial process requiring temperatures of up to 250⁰C should be possible, he said.

The process could be used to heat up oil or to boil water to generate steam and run steam turbines, producing electricity to run freezers and chillers and store food safely. This would offer considerable benefits to areas currently without electricity, said Sansom.

The technology could even be used to power desalination processes, so could be used to produce drinking water, he said.

“I’m working on a project with a company in Italy to manufacture low cost systems up to 250⁰C. It will be about three years before you could get something that would be a good investment for a company.”

Systems were currently too expensive to be commercially viable, he said, but he added: “In Italy and Germany we are building machines that will manufacture these systems much more cheaply.”

Sansom said some projects were being funded by the UK government and others by cash channelled through the European Commission’s Framework 7 research programme.