THE brains behind an award-winning solar power system says harnessing the sun’s unlimited energy is the way to go in addressing Lesotho’s electricity needs.
National University of Lesotho (NUL) lecturer, Anadola Tšiu’s solar energy system won a “Future Energy” prize at the BIE-Cosmos Expo 2017 in Kazakhstan in September.
Six projects from across the world were shortlisted to be showcased in the Energy Best Practices Area of Expo 2017 Astana, following a call for applications in February 2017. The jury recognised the relevance of the NUL project with regard to the “Future Energy” theme of Expo 2017 and its commitment to promote energy for all.
The solar energy system is an initiative of NUL’s Department of Physics and Electronics. It is a low-cost flat plate solar energy collector which uses the sun’s energy to heat water for purification and cooking, thus improving living conditions in rural areas of Lesotho where there is limited access to clean water and energy.
Dimitri Kerkentzes, Deputy Secretary General of the BIE, described the NUL project as “a concrete example of the core values of both Expo 2017 Astana and Expo ’90, to promote sustainability and environmental protection”.
Shinya Kubota of the Expo ’90 Foundation stated: “The National University of Lesotho’s project fully embodies the harmonious coexistence of nature and mankind, the fundamental principle of the Expo ’90 Foundation.”
Mr Tšiu said conventional solar heaters captured the sun’s energy and stored it in water, producing water circulation in the absence of electricity.
“But our solar water heater system is a bit more advanced; actually it offers three functions in one,” he said.
“It offers the traditional water heating for general use, space heating which includes under floor heating and wall radiation, and it can also generate electricity using the smart little known Organic Rankine Cycle technology.”
Explaining how the Organic Rankine Cycle operates, Mr Tšiu said: “We heat water first, and the water in turn transfers its heat to a refrigerant, which, upon evaporation, drives a turbine, producing electricity.”
He said it works much like an old steam engine except that steam engines were notorious for losing energy into the atmosphere. Our system conserves as much of the energy as possible.
“Once the refrigerant has been used to produce electricity, it is again cooled. It is cooled with water and the water in turn gets warm. Here is the beauty of our system, we don’t throw away that warm water, we use it to warm buildings,” he said.
Mr Tšiu also indicated that they were conducting trials in rural parts of the country to assess if they can build the solar water heater systems in bigger sizes.
The innovation has already been piloted in Nazareth, with two placed at the Pitseng High School hostels for both girls and boys.
Mr Tšiu also came second a year ago with an innovation focusing on addressing the energy needs of Basotho held in Germany.