Emissions up in Greater Toronto and Hamilton Area as reliance on gas power deepens: report

The increased use of natural gas to power the Greater Toronto and Hamilton Area is “undermining” efforts to cut into carbon emissions, according to a new report looking at the area’s planet-warming pollution.

The Atmospheric Fund, a regional climate agency, says emissions were up by one per cent in 2024. That marked slower growth than in previous years, but was well off the 11 per cent annual cuts the report says would be required to hit the region’s 2030 climate targets.

The report says electricity emissions were up 28 per cent — outpacing a two per cent demand increase — as a “direct consequence” of Ontario’s increasing reliance on natural gas to power the energy grid, which is expected to deepen over the next decade.

At the same time, the report says there are signs some climate actions are delivering results. Per-capita emissions dropped by three per cent even as the area added about 300,000 new residents.

Some of that progress is linked to home retrofit programs and electric vehicle charging infrastructure, the report says, underlining Toronto’s recent milestone of 100 electric buses in its transit fleet.

“Every retrofit, every electric vehicle, every clean energy investment creates jobs, drives innovation, lowers energy bills and builds resilience,” the agency’s CEO, Julia Langer, said in a statement.

Yet Langer said recent funding and climate policy rollbacks are “concerning.”

A major piece of Toronto’s climate plan is under scrutiny by the provincial government, after it passed legislation earlier this year that aims to prevent Ontario municipalities from enforcing mandatory green building standards.

More than a dozen Ontario municipalities have followed Toronto’s lead by pushing developers to design more energy efficient buildings with lower greenhouse-gas emissions, beyond what’s required by the provincial building code’s minimum standards. The report notes Ontario’s building code has not seen substantial updates to its energy or emissions requirements since Premier Doug Ford’s government came to power.

Most municipal standards are voluntary, but Toronto and Halton Hills are among those with mandatory requirements. Toronto has argued it still maintains the authority to enforce its standard, despite the law.

The province says the inconsistent standards lead to higher costs and added complexity for homebuilders. It’s currently holding consultations on the law.

Tuesday’s report says even though the recent law “complicates the picture,” it recommends municipalities should “maintain and enhance” the green standards.

Buildings account for just under half of the GTHA’s emissions, largely from gas-powered electricity and heating. Those emissions rose by 1.7 per cent from 2023 to 2024.

Ontario’s energy grid is the most polluted it’s been since 2012, before coal power was phased out. It was 84 per cent emissions-free last year, down from a high of 96 per cent in 2017, due to rising natural gas use.

Climate advocates have said the trend reflects the province’s failure to sooner invest in renewable energy and battery storage. The government, meanwhile, suggests it still plans to have an almost entirely clean grid by 2050 and the recent rise in natural gas is partly due to its flexibility and ongoing nuclear refurbishments.

“Ontario is focused on keeping costs down for families,” Energy Minister Stephen Lecce said in a written statement critical of rising utility bills under the previous Liberal government.

After buildings, transportation is the GTHA’s the next highest-emitting sector at 37 per cent. Return-to-office mandates are making it “increasingly difficult” to cut into those emissions, the report says, and it could likely get harder as the province directs all Ontario public servants back to full-time office work starting next year.

Transit ridership was up across the region but still remains about 13 per cent below pre-pandemic levels. Nearly 100,000 electric vehicles were registered in the GTHA last year, a 34 per cent increase over 2023.

“It is crucial that EV adoption continues to be accelerated through supportive policies and incentive programs,” the report said.

The GTHA covers Toronto and Hamilton, along with the surrounding regional municipalities of Durham, Halton, Peel and York. It represents 46 per cent of Ontario’s emissions.

This report by The Canadian Press was first published Nov. 18, 2025.