Faculty Spotlight – Heather MacLean


From plug-in hybrid vehicles to oil sands operations, Dr. Heather MacLean quantifies the environmental impacts through systems approaches such as life cycle assessment. 

While environmental concerns can motivate new energy policies, the complexity and interconnectedness of the global energy system present challenges for regulators. What are the net environmental benefits of a proposed technology? What are the net environmental costs of current practices? The stakes are high, the questions are straightforward, but the answers are very challenging to obtain. Life cycle assessment (LCA) approaches applied to energy systems are useful in providing insight to answer these questions. Life cycle assessment quantifies the environmental impacts associated with all stages of a product or process, for instance from resource extraction through production and finally to product (or energy) end-use.

Working with public and private sector partners, Dr. MacLean’s research has informed a wide range of energy processes. In a recent article in Environmental Science and Technology (2012), MacLean, colleague Dr. Matt Roorda and MASc. student Leon Raykin report how driving patterns and the local electricity grid influence the well-to-wheel greenhouse gas emissions from plug-in hybrid electric vehicles. While plug-in hybrids performed better than comparable internal combustion engine vehicles, the quantified benefit varied widely depending on, for example, hydroelectric vs. coal electricity sources and short vs. long distance vehicle usage. In another recent article, MacLean and collaborators compare two predominant oil recovery and extraction processes applied in the oil sands[EST 2012]. Dr. MacLean’s work has also quantified the environmental impacts of a variety of liquid biofuels and biobased electricity generation strategies, as well as wastewater treatment processes and residential density options. Collectively, this body of work is bringing some clarity to the difficult questions surrounding global energy usage.

More about Dr. MacLean and her research: http://www.civil.engineering.utoronto.ca/staff/professors/maclean.htm