A Ghanaian scientist has developed new materials that can be used to fabricate solar cells with improved efficiencies. The feat by Selina Ama Saah a lecturer at the Department of Chemical Sciences at the University of Energy and Natural Resources, Sunyani, could allow for solar cells to be manufactured locally, making it more affordable.
Until recently, hydro-electric power was the main of source energy in the country. Recurrent energy crisis which peaked in 2014 saw the break-down of key sectors of the Ghanaian economy.
The Institute of Social, Statistical and Economic Research indicate that erratic power supply cost the nation 3 billion dollars. Consequently, thousands of Ghanaians lost their jobs as many businesses either folded up or operated below capacity. Search for alternative sources of energy became more prominent and intense.
“At a point the Ghana Energy Commission came up with an energy policy for Ghana which indicates by 2030, 10 percent of the fuel that we use for our cars should contain renewable forms of energy.
“So we started looking at different types of feedstocks,” Prof Johannes Awudza, who is a solar energy expert at the Kwame Nkrumah University of Science and Technology said. Besides generators, solar-powered devices and solar panels became the most available means to ensure the constant supply of power.
“We added solar energy it is known that if we use solar energy then we reduce environmental pollution significantly,” he said
Unfortunately, these never come cheap because, for years, the basic manufacturing material for solar cells is silicon which is expensive. Use of high-purity silicon, high installation and importation costs are the main reasons behind the high cost of these solar cells.
She bumped into lead-based semiconductors during investigations into materials with properties similar to silicon for solar cell fabrication.
“Lead, we all know is toxic but it’s part of our environment because it’s the seventh most abundant heavy metal in the Earth’s crust.
“This research looked at alternative uses of lead not just being there and killing us but rather channeling it into energy. Lead-based semiconductors can be synthesized from lead complexes using simple spin coating techniques followed by annealing,” she said. Selina has so far developed an absorber which is part of the active layer in polymer-based solar cells.
The next stage of the research, she says, will be blending the materials that have been made with polymers to make a complete solar cell. “In the near future, we hope to see solar cells which are on plastic substrates that can be part of the device fabrication, so you need not to put the silicon on top of the roof; it can be with you wherever you go because it will be like the sticker type,” she stressed.