Swapping gas mowers for electric could help solve Colorado’s ozone problem: report

Trading in gasoline-powered lawn equipment for electric and battery-operated models could help curb the ozone pollution plaguing Colorado’s Front Range, a new report has found.

Making such a switch could achieve nearly one-fifth of the reduction needed to address the region’s unhealthy levels of this atmospheric contaminant, according to the report, released on Thursday by the Colorado Public Interest Group (CoPIRG) Foundation.

Operating a commercial gas-powered lawnmower for just one hour generates as much ozone-forming emissions as driving a 2017 Toyota Camry about 300 miles from Trinidad, Colo., to Cheyenne, Wyo., the authors said. 

Meanwhile, an hour of commercial leaf-blowing produces what the researchers described as “a staggering amount of ozone-forming emissions” — the equivalent of driving 1,100 miles from Denver to Calgary, Alberta.

“Gas-powered lawn mowers and leaf blowers may seem small but they pack a big pollution punch,” Kirsten Schatz, a clean air advocate for CoPIRG Foundation, said in a statement, noting that a phaseout of these devices could “go a long way.”

“To address Colorado’s unhealthy ozone pollution, it’s important we start transitioning away from gas-powered lawn and garden equipment as soon as possible,” Schatz added.

CoPIRG Foundation’s report was released ahead of a Colorado Air Quality Control Commission hearing on Dec. 13, at which time the agency will consider adopting an ozone reduction plan.

The Front Range — the section of the Rocky Mountains that runs from southern Colorado to southeastern Wyoming — has for decades grappled with significant ozone pollution, particularly in the summer.

A portion of that range, from just south of Denver to the Wyoming border, has for years failed to comply with federal ozone standards, according to the Colorado Department of Public Health and Environment.

An invisible but insidious pollutant, ground-level ozone can cause asthma attacks and respiratory illnesses, as well as damage agriculture.

Ozone forms in the atmosphere from chemical reactions of hydrocarbons and carbon monoxide in the presence of both nitrogen oxides and sunlight — meaning that summer is a peak period for ozone pollution.

Vehicles and oil and gas operations are the biggest local sources of the pollutant, according to scientists at the National Center for Atmospheric Research.

But prevailing daytime winds also transport ozone to the west — into the foothills and up to remote areas in Rocky Mountain National Park, the scientists found.

To meet federal air quality standards, the Front Range needs to bring ozone pollution down from a high of about 84 parts per billion to 70 parts per billion, according to the CoPIRG study.

Gasoline-powered lawn and garden equipment amounts for around 2.5 parts per billion of the Front Range’s ozone contamination, the authors added, citing data from the Regional Air Quality Council.

This is equivalent to almost one-fifth of what the region needs to cut, the authors stressed.

As a basis of comparison, all the region’s “on-road vehicles” contribute an estimated 6.8 parts per billion, according to the study.

The CoPIRG report authors recommended that consumers take proactive steps such as choosing an electric model when purchasing a new mower, leaf blower or power tool.

Meanwhile, they urged commercial operators and large institutions, including academic campuses and golf courses, to make similar transitions and thereby offer quieter experiences for their customers.

The report also highlighted the “Mow Down Pollution” incentive program offered by the Regional Air Quality Council, an agency that serves the Denver and north Front Range area.

While the program’s general funding is now depleted, some residents can still receive vouchers for purchasing electric gardening equipment.

The report expressed support for funding programs such as Mow Down Pollution and proposed extending such initiatives to commercial operators.

The authors also suggested that Colorado adopt regulations similar to those approved by the California Air Resources Board last year.

In December 2021, California’s board advanced measures that will require most new small off-road engines — which includes leaf blowers and lawnmowers — to be zero-emission by 2024.

“When we have so many zero-emission electric and battery-powered options to choose from, it’s silly to keep using polluting lawn equipment,” Schatz said.

“Not only is electric lawn equipment quieter, but it also requires less maintenance, and it’s cheaper and easier to power rather than running to the gas station with a can every time you need to fuel up,” she added.