“Everyone agrees that we don’t want to use fossil fuels, but unfortunately we’re not investing in the alternatives. Current global annual consumption is 160,000 TWh, and most of this, more than 80%, is not at all eco-friendly. Cutting our dependence on fossil fuels now would lead to catastrophe: we have to keep carbon going for a while longer, to avoid unmanageable human consequences”, says Xavier Crispin, professor of organic electronics in the Laboratory of Organic Electronics.
Forecasts in the World Energy Outlook for 2020 also show that it is uncertain whether the ongoing pandemic will lead to the current trend of a rapid increase in renewable fuels and electricity production continuing or not. Even in a positive forecast, based on the political landscape as it is now, the fraction of carbon-based energy will not fall below 20% before 2040.
Xavier Crispin has calculated that an area of solar cells corresponding to 240,000 km2 would be necessary to satisfy global requirements, slightly more than half of the area of Sweden, using currently available technology. Is that possible?
“Oh yes,” he claims, “but it would need huge amounts of material to deal with the solar energy produced. This would require a realignment in society.”
Vast numbers of solar cells are required, preferably eco-friendly organic solar cells, and organic batteries that store sun and wind energy and can compensate for load variations in the electrical supply grid through the day. The technology is available: batteries are currently manufactured as rolls in a printing press by Ligna Energy in Norrköping, a spin-off company from the Laboratory of Organic Electronics. The batteries consist of forest-based raw materials: cellulose and lignin. Their efficiency is about the same as conventional car batteries, but they can be recharged at least 5,000 times and can be incinerated when no longer in use since they consist of natural raw materials.
Researchers at the Laboratory of Organic Electronics have recently developed and patented a completely organic “redox flow battery”. While it is true that the current battery is rather large, it is based on water, safe, and can be recharged without limit. The battery is ideal for charging with sun or wind energy, and for use as a power bank for electric cars.
Printed solar cells
Solar cells that harvest energy from ambient light to power sensors and other equipment in the home is already available in rolls. Olle Inganäs lies behind the technology.
Photo credit Thos BalkhedSolar cells can also be manufactured on rolls in a printing press, and here another spin-off company from Linköping University, Epishine in Linköping, is leading the field. The first product is a solar cell that harvests energy from indoor ambient light, used to power sensors and other gadgets in the home. The company, however, has much higher ambitions. The solar cells can be printed onto large surfaces, in different colours, and they can be installed in windows and on building façades.
Olle Inganäs, professor emeritus in organic electronics and one of the true pioneers in the field, lies behind the technology.
“If we could get the same budget for research into organic solar cells as the motor industry has for marketing cars in southern Italy, we would be able to make major progress into solving the world’s energy problems”, Olle Inganäs claims.
Environmentally friendly fuels
Another example of research at the Laboratory of Organic Electronics is a quest for new and environmentally friendly fuels for fuel cells. The hydrogen gas used in fuel cells is currently derived mainly (96%) from non-renewable sources. Research groups at Campus Valla have similar projects under way, in which, for example, a research group led by senior lecturer Jianwu Sun is using solar energy to convert carbon dioxide and water to fuel. Maybe in the future we can use plants to store energy. This research has also made major progress, under the leadership of research fellow Eleni Stavrinidou, in the Laboratory of Organic Electronics.
In the near future, research carried out within traditional silicon-based electronics will also bring major changes to our everyday life. Professor Atila Alvandpour and his group in the Department of Electrical Engineering have, for example, developed small electronic circuits powered by energy that they harvest from the surroundings. These circuits are used in, for example, pacemakers charged by the energy from heart beats, and in other medical implants where changing batteries is not possible, or causes serious problems.
To sum up: bring research results into use, so that we can better use the renewable energy we have around us. Large and small energy contributions – we need them all in a world of increasing sustainability.
Translated by George Farrants