Cooling is one of the fastest growing uses of energy. Domestic refrigerators and air conditioning systems are selling very quickly as incomes rise in China, India and other parts of the world. Heavy industry, data centres and food storage, processing, distribution and retailing all use a growing amount of energy intensive cooling. Many of the chemicals used as refrigerant coolants are themselves powerful greenhouse gases. All this represents a very serious problem from a climate change point of view. What could be done?
Well designed and insulated buildings can reduce demand for cooling just as they can for heating. Passive house style housing is beginning to take off in countries like Germany and Austria where the main requirement is for heating. High thermal mass, good insulation, breeze capturing windows and towers and well situated shading have all been used in the past to provide comfortable buildings in hot climates and could all be developed and incorporated into more modern urban contexts. Where this kind of design is applied the need for air conditioning will be very much less.
Solid Solar are a pioneering Austrian company designing and installing large scale solar thermal heating and cooling systems. A few weeks ago they installed a 5,000 square metre solar thermal roof to provide air conditioning at the Desert Mountain High School in Arizona. Where air conditioning is necessary this seems to me to be the best way to do it.
In many tropical countries huge amounts of food are wasted due to lack of cold storage and transport, and so naturally more refrigerated trucks are being used in, for example, India. Refrigerated trucks are doubly polluting, using diesel both for movement and cooling. Again, what could be done?
Peter Dearman is the British inventor of the Dearman engine, which uses liquid nitrogen as a fuel for power and cooling. The Croydon based company is expanding with a particular focus on refrigerated trucks especially in rapidly expanding markets such as India. The basic technology could have many other uses where both power and coolness are required at the same location, for example in data centres or supermarkets. This is very exciting and might well be my technology of the year!
SOLID Solar http://www.solid.at/en/