Let’s begin by saying this is a story about a laboratory experiment that may be good news for renewable energy advocates in the future. It has no practical industrial application at the present time. But how a technological breakthrough in solar panel design came to be is fascinating.
Dr Gavin Bell and Dr Yorck Ramachers are researchers in the physics department at the University of Warwick in Coventry, England. They recognized that conventional photovoltaic solar panel technology has reached a practical limit when it comes to improving efficiency and lowering manufacturing costs. Any gains from this point forward are likely to be incremental at best.
So, the pair went back to the research and writings of Nikola Tesla and Albert Einstein to see if the work those pioneers did could point the way to a better panel design. A present, a solar panel relies on a vacuum between the outer surface and the solar cells inside. What if, Bell and Ramachers asked themselves, they used a gas like argon to fill that space? What they envisioned was really a variation of a modern double-glazed window.
In the prototype the scientists built, the outer pane is transparent and conducts electricity. The inner pane is coated with a special material developed in the lab which releases electrons when illuminated by sunlight. They call that layer a “photocathode.” In the presence of sunlight, electrons are kicked loose from the photocathode, travel through the gas. and are collected by the outer pane. Dr. Bell says, “It’s satisfying to find a new twist on ideas dating back to the start of the 20th century, and as a materials physicist it is fascinating to be looking for materials which would operate in an environment so different to standard photocathodes.”
Bell and Ramachers hope their work will act as a catalyst for further investigation by materials engineers. The optimum composition of the photocathode layer is yet to be determined. Although, they think a thin diamond film would be very durable. They also think the photocathode layer could have variable transparency, making it suitable for solar windows. Filling the inside of the panel with an inert gas like argon could also cost less to manufacture than creating a vacuum.
“We think the materials challenge is really critical here so we wanted to encourage the materials science community to get creative,” says Bell. “Our device is radically different from standard photovoltaics, and can even be adapted for other green technologies such as turning heat directly into electricity, so we hope this work will inspire new advances.”
We know you get tired of hearing news of potential breakthroughs in the lab that promise better electric car batteries, better solar panels, or better ways to make hydrogen from water. Most of those developments never make it out of the laboratory. There is no information available yet on how much electricity one of these gas-filled double-glazed solar panels can generate, how efficient it might be, or what it might cost. All those answers are yet to be supplied or discovered.
What deserves our attention, though, is the willingness of two scientists to go back and do a total rethink of solar panel technology. Maybe nothing will come of their work. But then again, they may have just made a quantum leap in renewable energy technology. This is one story of an advance made in a laboratory worthy of following.
Source: University of Warwick