UK tech start-up Gravitricity has unveiled plans to explore the energy storage potential of South Africa’s former mine shafts, thanks to a £300,000 funding boost from government agency Innovate UK. The company’s energy storage technology works by raising multiple heavy weights, weighing up to 21,000 tonnes in total, in a deep shaft and releasing them again to power a generator when the energy is required.
“The country has ambitious plans to develop more renewable energy, but at the same time there is a lack of supply and robust grid infrastructure to carry power to factories and people’s homes – particularly at peak times,” explained Gravitricity’s managing director Charlie Blair. “Our technology uses repurposed mine shafts to store excess energy and then release it when required – either in very rapid, short bursts or over a long period of time. This takes pressure off the grid and helps smooth supply at vital times. And because South African mines are so deep, this means we can store even greater quantities of power.”
“The South African electricity market is in crisis,” said Melani De Lima, research analyst at RESA. “Since 2008 the country has been faced with intermittent periods of load shedding. Even though the renewable energy technologies brought online by the country’s Renewable Energy Independent Power Producers Procurement Programme [REIPPP] provide a cleaner, greener solution to our country’s electricity supply problems, it does not solve the problem of intermittent electricity supply to the South African grid.”
Source: Business Green
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