Clean, quiet and fast, electric or hybrid vehicles are the future of automotive transportation. But today’s models could be even more efficient if improvements were made to their air conditioning systems. “It takes as much energy to run the air conditioning as it takes to push the car to 80 km/hr,” says Todd Pratt, CEO of Future Vehicle Technologies (FVT), maker of a high performance electric sports car in Maple Ridge, BC. FVT is an industrial partner in a $1.38M research collaboration led by SFU engineering science professor Majid Bahrami.

This next-generation system will improve the efficiency of lithium/ion battery systems in electric vehicles. One idea is to use the low-grade heat generated by the batteries, power electronics and electric motors to power a new adsorption air conditioning system to cool the passenger compartment as well as the batteries themselves. Bahrami says, “A major problem with these electric vehicles is that as soon as you use the battery to drive a compressor in the air conditioning unit, you reduce the driving range of the vehicle by up to 38%.” By exploiting waste heat to power the air conditioner, Bahrami’s technology avoids this problem. “That’s why both NSERC and Automotive Partnership Canada has funded this project,” says Bahrami. The Canada Foundation for Innovation and Natural Sciences & Engineering Research Council of Canada are contributing $798,906.

“Refrigeration and air conditioning research has been overlooked in Canada,” says Bahrami. He points out that 8% of the energy consumed by human society is related to refrigeration and air conditioning. Think of the storage and transport of milk, for instance. Virtually all refrigeration systems are based on a vapour compression cycle in which a compressor runs on electricity and ultimately from fossil fuels, so refrigeration has a significant greenhouse gas component. “We need to shift to low grade thermal energy sources, temperatures of 200C or less, to create sustainable air conditioning systems,” says Bahrami. This is heat that is typically discarded, such as the exhaust from an internal combustion engine or car radiator.

Adsorption cooling has been around for 150 years. It adsorbs a refrigerant (e.g. water or methanol) with no environmental impact because all the materials are benign. The key bottleneck is finding a way to enhance heat and mass transfer inside the adsorption beds, the heart of the system. “Our focus is a zeolite and water pair,” says Bahrami. His research team is  working on reducing current bulky systems by employing microstructure porous media.

“I’m very excited about this. It’s one of the hottest research areas in the world,” says Bahrami. “If we can do it, we’ll be one of the pioneers in this area.”
Bahrami spent his undergraduate years at Sharif University of Technology in Tehran. He then worked for five years in the air conditioning industry as a researcher in Iran, Germany and Canada before completing a PhD at Waterloo University. He came to SFU in January 2009.

Bahrami says, “We are very serious about alternative and sustainable energy conversion systems and we are open to collaboration. Our lab is one of the best in the country, when it comes to sustainable refrigeration research.”