It is one of the perennial problems of developing renewable energy sources – how to produce it on a cost effective, industrial scale that competes with current fossil fuels. While politicians and activists talk of subsidies and carbon footprints, the scientists have been working hard to come up with effective solutions.
Now researchers at the University of Liverpool may have come up with a solution for replacing the toxic components of solar energy cells and the new manufacturing process could well bring down the cost in the process.
The replacement? A material found in bath salts. The research team led by Dr Jon Major believe that it may even bring down the price of solar energy comparable to fossil fuels. It has been a long search for a cheaper version of the solar energy cells. Approximately 90% of them have been made using silicon but around 7% are made from cadmium telluride which is considered cheaper and lighter.
The problem is that cadmium telluride requires toxic cadmium chloride to manufacture, and a large portion of the cost is used in making it safe for people to work with and disposing of the side products. On its own cadmium telluride actually converts 2% of sunlight into useful energy. Add the cadmium chloride and this shoots up to 15%.
The team from Liverpool University has discovered that the process can work equally well with the non-toxic magnesium chloride – a core constituent of household favourites such as tofu and bath salts.
One of the challenges of solar energy has always been how to make it cheap enough to compete with fossil fuel production and, according to some experts, this could be a major breakthrough in making that possible.
It is still early days but Director of the Stephenson Institute at the university, Professor Ken Durose, said that the cost reduction may well bring the price of electricity production for something like a large scale solar farm down below the current cost of gas electricity production.
It is not a claim that has gone uncontested. Some industry experts believe that the scientists may be over stating the potential impact of their discovery. The cost of dealing with cadmium chloride and the use of toxic materials presents a small fraction of the production costs and telluride is too rare a material to ever be manufactured cheaply.
The Stephenson Institute is part of the Faculty of Science and Engineering at University of Liverpool and was set up to explore the future of clean, renewable energy sources.
According to Dr Major: “Cadmium chloride is toxic and expensive and we no longer need to use it. Replacing it with a naturally occurring substance could save the industry a vast amount of money and reduce the overall cost for generating power from solar.” Magnesium chloride can be extracted from seawater
It remains to be seen if this new discovery will have an impact on solar cell production but it is a step in the right direction, helping to bring the cost down and raise hopes of a more sustainable future.