Why Electricity is Called Hydro in Some Parts of Canada

28 May, 2026

You might hear someone say “I ran hydro to that building” or “they put new hydro lines in.”

Water? No. Electricity.

Why?!

“Hydro” is a shortening of “hydroelectricity,” which is electricity generated from dams using gravity and a turbine.

In Ontario, the word gained popularity when the Hydro-Electric Power Commission of Ontario was formed in 1906 to build power lines from private dams to municipalities. The Commission was later renamed to Ontario Hydro.¹

Considering they owned the power lines, it makes sense to say, “We ran Hydro to the new building.” Notice my intentional capitalization. I think that the first uses of “hydro” referred to the power lines owned by the hydroelectric corporation, and over time, “hydro” evolved to refer to the electricity carried by those lines.

The earliest reference to “Hydro” in the OED is from Ontario, and it’s capitalized!² I think this is good evidence that the author was referring to the corporation rather than to electricity.

By 1970, the example usage is in lowercase and clearly refers to electricity.

In Ontario, as towns became electrified, they likely picked up on the colloquial name “Hydro” pretty quickly. Many Ontario municipalities have a long history of using water to power factories and mills. So there’s a chance that “Hydro” had a familiar, affectionate tone to it.

Many provinces have similarly named power corporations, although they were established much later. Usually in the 1950s-60s: Quebec has Hydro-Québec, Manitoba has Manitoba Hydro, and they even named their office building “Manitoba Hydro Place,” Newfoundland and Labrador has “Newfoundland and Labrador Hydro,” referred to as “Hydro” on Wikipedia,³ and British Columbia has BC Hydro.

I’ve extracted some commentary from two Reddit threads^{4 5} below so you can see how the language around electricity changes from one region to another. I have tried to be accurate here and represent the difference between the word for what runs through the lines (power/electricity/hydro) and the name of the bill.

I’ve left cells blank where I couldn’t find what the correct word was. You can see that it’s common to refer to the bill by the name of the company that delivers the electricity. Ontario is the only province where I could find a reference to someone simply saying “did you pay the hydro?” without “bill” on the end. Similarly, as I noted with the Wikipedia page for Newfoundland and Labrador Hydro, Newfoundland is the only place that still refers to the power corporation as “Hydro” with a capital letter.

Is it really Hydroelectric Power?

No. Nationwide, 61.7% of Canada’s electricity was generated by hydroelectric dams in 2022.⁶ Pretty good! Actual numbers vary from province to province and year to year. The remainder of the nation’s electricity is from natural gas, nuclear, coal, wind, and solar.

In Ontario, only 23% of the generating capacity is hydroelectric—hardly “hydro” at all—the rest is:

• 34% Nuclear
• 28% Oil and gas
• 15% non-hydroelectric renewables⁷

Manitoba, Quebec, and British Columbia top the list for their hydroelectric capacity, all well over 90% of their total capacity.

While Manitoba has the highest hydroelectric capacity as a percentage of its total capacity, Quebec generates more megawatts overall since its total capacity is higher. For example, Quebec can produce 37,370 megawatts of hydroelectricity ⁸ whereas BC can produce 12,049 megawatts,⁹ and Manitoba can produce 6,100 megawatts.¹⁰

“Hydro” seems to be a uniquely Canadian word for “electricity,” and its usage varies across the country. The irony here is that in a province like Ontario, people say “hydro” where “nuke” might be more appropriate!

“Ah shoot, the nuke went out in the middle of baking a cake!” just doesn’t sound right.

#blog #electricity