Purchasing a large household appliance, like an oven, fridge, or freezer? I bet you take your time to compare different features of similar products, including their energy efficiencies. After all, a refrigerator will consume thousands of kilowatts of electricity over its lifetime, and cost you hundreds of dollars. You know that better efficiency means you have a greener appliance that saves you money.
Purchasing electricity? (I know you are because you’re reading this blog!) It’s sort of similar to purchasing an appliance. Every time you turn on a light or computer, you’re making a purchase that can result in unintended consequences – like releasing greenhouse gases (GHGs), a major driver of climate change. At the individual level, there won’t be a significant amount of GHGs released from turning on a light. But, everyone’s purchases taken together, combined with the electricity used by companies or institutions, can result in large amounts of GHGs being released. This is especially true during peak demand periods, when more fossil fuel-fired generating stations (like gas-fired ‘peaker plants’) are in the mix.
What’s an enlightened, environmentally conscious consumer to do?
One useful tool is an emission factor: the amount of GHGs released per unit of energy produced by suppliers (and ultimately consumed by users.) The Independent Electricity System Operator (IESO) could make the estimated GHG emission factors for Ontario’s electricity consumption publicly available on an hourly basis. In my Annual Energy Conservation Progress Report – 2011 (Volume One), I recommended that they do just that. This was motivated by my desire for electricity consumers to have information that could help them make environmentally conscious decisions about when they consume electricity.
Right now, such information is available from sources like Environment Canada’s Electricity Intensity Tables, which provide an annual greenhouse gas intensity factor for each province’s electricity system. Unfortunately, this annual greenhouse gas intensity factor doesn’t reflect the hourly variation of our electricity system. Plus, publication of the annual greenhouse gas intensity factor is delayed by a couple of years.
Clearly, an annual emission factor does not accurately reflect the carbon intensity of our electricity system during any given hour of the day. This is inadequate for anyone who would like to reduce their carbon footprint by shifting their electricity consumption.
Why would you be interested in shifting your electricity use? Because Ontario’s sources of electricity supply – and the consequent production of GHGs – vary throughout the day. It is a dynamic system where generators are turned on and off to meet our varying energy needs – and generators rely on different fuel sources and technologies. As energy demand changes hourly, weekly and seasonally, the amount of GHGs emitted to the atmosphere by electricity generators also fluctuates.
I’m not the only person who sees this problem. Last year, my staff met with researchers at Niagara College who published an interesting peer-reviewed approach for calculating hourly emission factors. Other researchers have been exploring similar issues, such as looking at the emission intensity factors for marginal electricity generation.
There’s also momentum from the private sector behind this idea, including the creation of an app to help people see what their hydro bills are paying for. The Gridwatch (Ontario Edition) app was launched last year for iphone users, and is free to download. It provides users with an easy-to-read interface that shows you how much power is being generated, from what electricity source, and it even calculates its own estimate for Ontario’s hourly GHG emissions from electricity generators. This helps consumers learn more about their electricity use and the associated GHG emissions.
Wouldn’t it be useful to have an official method that is endorsed by government and industry to calculate hourly GHG emission factors for Ontario’s electricity consumption? I think so. I believe that an official source for real-time GHG emission factors could help industries calculate their emission reductions from load shifting, could help academics studying GHG emissions from our electricity system, and help you, the public, make decisions on when and how to use electricity with the least impact. The generation data is already being collected and it would improve the public’s understanding of our electricity grid and how our electricity use is related to reducing our GHG emissions. Let’s get an official source of hourly GHG emission data for our electricity system available!