In the ever-evolving, varied world of sustainability, it can be a challenge keeping up with the units of measurement. As SustainableBiz Canada uses these terms frequently, the units of measurement will be explained for the readership to gain an idea of what these metrics mean.

Electricity

Watt (W) – A watt is a unit of measurement for power to represent energy transfer. It is typically employed for household appliances like lightbulbs or home electronics.

Kilowatt (KW) – A kilowatt is 1,000 watts. It is used for moderately energy-intensive home appliances.

Megawatt (MW) – A megawatt is 1,000 kilowatts. It is frequently used for utility-scale and city-wide energy use. Most clean energy and renewable energy projects are megawatt-scale.

Gigawatt (GW) – A gigawatt is 1,000 megawatts. Gigawatts are typically used for expressing the energy generation capacity of several power plants or a province’s energy consumption. The U.S. Department of Energy pegs one gigawatt to 333 utility-scale wind turbines or 3.125 million photovoltaic panels.

Terawatt (TW) – A terawatt is 1,000 gigawatts. Terawatts are best used for national- or international-level energy generation.

Electricity per hour

Kilowatt hour (kW-h) – A unit of measurement for a kilowatt of electricity sustained for one hour. It is often used for home appliances or home electricity consumption. EnergyRates says the average Canadian household uses 11,135 kW-h of electricity per year.

Megawatt hour (mW-h) - A unit of measurement for a megawatt of electricity sustained for one hour. It is often used for homes or utility-scale energy generation.

Gigawatt hour (gW-h) - A unit of measurement for a gigawatt of electricity sustained for one hour. Carbon Collective says gigawatt-hour is frequently used to measure the annual output of power plants and compare different power plants.

Terawatt hour (tW-h) - A unit of measurement for a terawatt of electricity sustained for one hour. The latest figure from the Canadian government puts Canada’s electricity production in 2019 at 632.2 tW-h.

Peak energy

Megawatt-peak (MWp) – The power output of a solar energy system operating at ideal conditions.

Carbon

Tonne of carbon dioxide – Equal to 1,000 kilograms of carbon dioxide. The U.S. Environmental Protection Agency (EPA) lists a tonne of carbon as equal to consuming 2.3 barrels of oil or 1,106 pounds of coal burned.

Megatonne of carbon dioxide – Equal to one million tonnes of carbon dioxide. In 2020, Canada emitted 672 megatonnes of carbon dioxide equivalent.

Gigatonne of carbon – Equal to 1,000 megatonnes. Gigatonnes are frequently used to measure global emissions. In 2022, the world emitted around 58 gigatonnes, according to the Brookings Institute. This is equal to the emissions from 15,525 coal-fired plants, using the EPA’s calculator.