A running commentary on the policy implications of the convergence of energy and environmental issues in Canada and the rest of the world
This site, Electric Power Statistics, provides information about the air emissions associated with grid electric power. This information is presented and organized by power market, and covers grid electricity. Statistics are based on power generator output, which is published by the electricity system operators in each market.
This information allows you to understand the emissions that are associated with the power you are using, in near real-time. This will help you make informed choices about, for example, the best times to operate major electric appliances. It will also help you understand the environmental reasons for governmental encouragement to shift your peak demand to other times.
This information is also essential in planning for the next investments in electricity supply. By seeing the effects of different kinds of power generation on the overall air emissions in an electricity system, you will gain a better appreciation of how upcoming generation investment decisions will affect air emissions in the future.
EPStats.com displays this information in three major ways: (1) emission intensity, in grams of greenhouse gases per kilowatt-hour (kWh), (2) total greenhouse gas emissions during a specified period, and (3) total electricity output from the system in question. Currently this information is presented on a system-wide basis; soon, you will be able to see generation emission breakdowns by fuel type and generator portfolio.
Emissions are measured both as a ratio of generator output, and as total-by-period. The basic metric for the ratio is emission intensity in grams of emissions of greenhouse gases per kilowatt-hour.
Emission totals are calculated from the emission intensity of the fossil-fueled generators in the system. Typically, these include coal, gas, and oil. The emission intensity of fossil fuels depends on the type of fuel (e.g., different types of coal yield different quantities and compositions of emissions when burned), and the technology that is used to burn it.
Power generator output figures come from the Independent Electricity System Operator, which manages Ontario’s electricity system and operates the provincial wholesale power market. The IESO updates generator output figures every hour, at approximately ten minutes past the hour. The published figures represent generator output from two hours prior to the update. E.g., figures published at 0810 represent generator output at 0600.
EmissionTrak™ takes the output from each individual fossil-fired generator and applies an emission factor to it. This factor takes into account the physical characteristics of the generator in question—make, model, technology—as well as the fuel the generator burns.
For a general idea of the emissions relating to Ontario generating plants, see Environment Canada's “National Inventory Report, 1990-2004 - Greenhouse Gas Sources and Sinks in Canada.” Please bear in mind that the electricity generation figures in this document—and the emissions and emission-intensity estimates that are based on them—include off-grid sources. The figures produced by EmissionTrak™ and published in Electric Power Statistics are for grid-connected generators only.
These factors, which are annual averages, are applied to the different kinds of fossil fuel-fired generators that provide power to Ontario’s system. Currently, the emission figures are for greenhouse gases only; emission figures for other pollutants, such as oxides of nitrogen (NOx) and oxides of sulfur (SOx), will soon also be available.
The factors are applied as the IESO data becomes available, so that you can see the emission intensity, and total emissions, associated with Ontario electricity generation in near real-time.
Please note: the emission totals and emission intensity figures are approximations only. While EPStats.com is working with various government agencies and international regulatory bodies to make these figures as accurate as possible, the currently published figures are intended to provide general and approximate information only. They do not currently provide, and are not currently intended to represent, that system’s official emission inventory.