Keeping cool in an ever-warming world

Here in Canada, we love summer.  Our winters are cold, and our summers are relatively short.  Each year as our long dark winters come to an end, we are eager to shed our heavy clothing for shorts and T-shirts, get outside and enjoy the sunshine.  So, who would imagine that in what most would consider a cold country, we would have to learn how to live with summer after summer of extreme heat? 

Yes, it is hot outside.  Record-breaking heat waves in North America and Europe have resulted in thousands of heat-related deaths, devastating wildfires, and catastrophic floods.  In Canada, we learned about “heat domes” in late June with headlines like “‘Heat dome’: Ontario, Quebec battle scorching temperatures”.  And just this week we see it in the United States as “100 million to swelter daily in massive US heat dome”.  This relentless warmth has become a defining feature of daily life for millions around the world.

Extreme heat puts immense stress on power grids, as surging temperatures drive up demand for air conditioning and cooling. Transmission lines and transformers operate less efficiently in hot weather, increasing the risk of equipment failures and localized blackouts. Utilities are forced to balance record-setting peaks in electricity usage just when their infrastructure is most vulnerable, often resorting to rolling outages or emergency measures to maintain grid stability. As the world is getting hotter, more people are finding that air conditioning is not just desirable, it’s essential.

Yet, when we talk about future electricity demand growth, it is Artificial Intelligence (AI) and its voracious appetite for electricity and the massive growth of data centres that are in the headlines.   Today, data centres make up about 1.5% of global electricity demand which is expected to double by 2030.  On the other hand, air conditioning is currently around 7% of global electricity demand and according to the International Energy Agency (IEA), is expected to triple by 2050, becoming one of the largest drivers of global electricity consumption.

This surge is driven by population growth, urbanization, and a rising global middle class—especially in countries with hot and humid climates like India, Indonesia, and parts of Africa. The result? A dramatic and sustained increase in electricity demand, particularly during the hottest parts of the day and year.

Globally, only about 1 in 10 people in the hottest regions have access to air conditioning, compared to over 90% in wealthier countries like the United States and Japan. As incomes rise and temperatures soar, demand for cooling is expected to skyrocket – especially in countries that are already energy-constrained.

This isn’t just a future problem for tropical nations. In North America, the effects are already visible. In Canada, electricity demand is shifting.  While winter heating has long been dominant, many provinces are now seeing record summer electricity peaks driven by air conditioning loads during heat waves.  In the United States, heat-related demand spikes are even more dramatic. In July 2023, for example, Texas set an all-time record for electricity demand—over 85,000 megawatts—as air conditioners strained to keep up with a prolonged and dangerous heat dome.  Similar records have been set in California, the Midwest, and New England.

Ensuring there is sufficient generating capacity to meet this growing demand while also making our grids more resilient to extreme weather is critical.  Nuclear power can provide reliable electricity to help meet this growing need.  Cooling is becoming central to health, productivity, and economic development. If we want to meet that demand cleanly, affordably, and reliably, nuclear power must be part of the solution.