University of Calgary Study Finds Large-Scale Adoption of PHEVs in Alberta Could Support Wind Power; PHEV GHG Benefits Range from 40-90% in Emissions Reduction
The environmental benefit of a large-scale deployment of plug-in hybrid electric vehicles (PHEVs) in the Canadian province of Alberta could vary significantly, ranging from a 40% to a 90% reduction in greenhouse gases, according to a study by electrical engineers at the University of Calgary’s Schulich School of Engineering. The study found the environmental impacts of PHEVs in Alberta would depend on factors such as vehicle battery size, charging time and wind production levels.
Power generation in Alberta is thermal-dominated. Of the installed capacity of just above 12,000 MW, approximately 49% (5,893 MW) is coal fired, 39% (4,686 MW) is gas-fired, 7% (869 MW) is hydro, and 4% (497 MW) is wind powered. However, the Alberta Electric System Operator (AESO) has nearly 11 GW interest in wind power developments, and is facing an operational challenge given a thermal-dominated system with limited flexibility. The AESO has thus been actively looking at ways to mitigate the high volatility of wind.
Optimal use of clean energy is especially important in Alberta, the Canadian province with the highest amount of thermally generated power in Canada and also home to the majority of oil-sands production. More than 90% of electricity in Alberta is produced by methods that emit greenhouse gases: burning coal, oil or natural gas.
Considering the potential application of PHEVs as a distributed storage system, the researchers note, PHEVs could be further promoted by the regulator in the province as a tool to offset wind intermittency.
The research of professors Hamid Zareipour, Bill Rosehart and PhD candidate Mahdi Hajian will be presented next week at an international power engineering conference in Calgary, the Institute of Electrical and Electronics Engineers (IEEE) Power & Energy Society General Meeting.
They say Alberta needs smart charging systems to make the most of the province’s wind resources. Infrastructure would include technology with communication links to allow system operators to distribute electricity to vehicles when wind power production is at its highest, usually at night.
Even in a thermal-dominated system like Alberta, we can still benefit significantly in terms of environmental impacts by using plug-in hybrid electric vehicles. If we plan to charge them in a smart way, we can reduce a significant amount of emissions in the transportation system.—Hamid Zareipour
Smart charging systems would also help the power system handle the increased demand for electricity resulting from widespread adoption of hybrid cars. Cars would be charged outside of peak demand times to avoid overloading the grid.
The whole idea is to consume the wind power in the system as much as possible. Unfortunately, the wind is unreliable because it’s not always blowing when we need it. Smart charging systems would help us harness the wind so we can store it in the vehicles’ batteries for later use.—Mahdi Hajian
The researchers used 2007 wind production levels and assumed 30% of Albertans were driving PHEVs when they considered four charging scenarios: battery charging at night, during the day, randomly through the night and randomly over a 24-hour period.
While wind energy production mostly happens at night, all four scenarios point to the need for smart charging systems. The results of the study are specific to Alberta but the conclusions could be applied elsewhere.
The researchers say other provinces should also have smart charging systems, but the need would depend on electrical load patterns and the availability of clean energy sources such as hydro.