A New Cooling Device
Chris - What is it that you have invented?
Alex - Our team has discovered a giant electro-caloric effect in thin films. The electro-caloric effect is a change in temperature in an insulating material. It is made through the application of a voltage.
Chris - So what you're saying is that when you apply a voltage to something, it changes temperature.
Alex - Yes, exactly.
Chris - So was this known before you came along or is this new?
Alex - The electro-caloric effect has been known for several decades and prototypes of electro-caloric fridges were built in Russia and the States. They were not commercially feasible because the electro-caloric effect in normal materials was not large enough.
Chris - Ok, well just talk us through step-by-step how it all works and what you actually do.
Alex - You take a piece of silicon which is about half a millimetre thin and about one centimetre squared. You then deposit a thin ceramic film on it, and then deposit an electrode on top of your film. The application of a voltage causes the film to change its temperature and if you build a snadwich structure, then this sandwich structure can develop a temperature difference of up to about twenty or thirty degrees centigrade.
Chris - But it's presumably not efficient for fridges? I say that because a fridge is already so effective that this wouldn't add much to that.
Alex - Yes. Fridges are quite efficient but they use greenhouse gases, so those greenhouse gases contribute to the global warming effect. Even if our new device isn't as efficient as fridges, people maybe still want to replace greenhouse gases in their fridges.
Chris - So assuming that that doesn't happen in the near term, what else could you do using your electro-caloric effect invention?
Alex - We can do air conditioners, for example, and that is more interesting because air conditioners usually work all the time. We can compete with traditional air conditioner inefficiency. Surprisingly, the same materials can also be used to convert low-grade waste heat into electrical energy. Waste heat is produced in everything, from computers to mobile phones and indeed in almost all electric and mechanical devices.
Chris - So how did you come to discover this in the first place? You won Science Graduate of the Year this year and that's pretty prestigious. What actually is that and how did you get to be doing this work?
Alex - The Science Graduate of the Year is an award by the Royal Institution of Great Britain and L'Oreal. That's prestigious and I'm very happy that I won that prize.
Chris - What did you win for winning it?
Alex - I'm a life member of the Royal Institution and I gave a lecture in London in the Royal Institution and I'll give a lecture in Paris. They also gave me some cash.
Chris - Which is always nice! Alex Mischenko, thank you very much.