OPEI Small Engine Fact Sheet
The tens of millions of small engines that power equipment all across the country are more efficient than ever before, and they play a vital role in the global economy. When firefighters use chainsaws to fight fires and clear debris after a storm, or when business owners use water pumps to clean out a flooded store after a hurricane, or when homeowners use portable generators to provide power after a tornado, they’re using small engines.
Small engines are ubiquitous
Outdoor power equipment is found across the United States and across the world in garages, maintenance sheds, fire stations, on construction sites, and at the front lines during natural disaster emergency response.
Landscapers, firefighters, construction crews, homeowners, and business owners use their outdoor power equipment every day, and small engines are core critical in equipment servicing the landscape, golf, forestry, construction and many other industries.
OPEI members produce those small engines and the equipment they power, including lawnmowers, chainsaws, UTVs, snow throwers, generators, trimmers, trenchers, power washers, blowers, garden tractors, chippers, grinders, concrete saws, power trowels, compact construction equipment, water pumps, and more.
In 2016, nearly 30 million small engines were manufactured in the United States – and each one was subject to stringent emissions regulations by both the U.S. EPA and the California Air Resources Board. Engine manufacturers work hand in hand with these agencies, as well as international regulators, to make sure their small engines are compliant with strict emissions regulations wherever they are used.
Small engine technology advancements
Outdoor power equipment has come a long way since your grandfather’s lawnmower. Today’s small engines are highly regulated, resulting in higher efficiency and lower emissions than previous engines. A series of regulations imposed during the last 25 years has driven major engine design and technology changes. New two-stroke engine technologies, such as air scavenging and exhaust system catalysts, are common.
In many applications, two-stroke engines have even been replaced by more efficient four-stroke engines. Four-stroke engines have improved as well: Automotive overhead valve technology is now the norm, resulting in more complete and efficient combustion. Today’s products also now incorporate low-evaporative emissions fuel system components like tanks, fuel lines/hoses, caps, and carbon canisters to further reduce emissions. Electric fuel injection options are growing and manufacturers have introduced gasoline and diesel hybrid models.
Beginning in the 1990s, both the California Air Resources Board (ARB) and the U.S. EPA put in place stringent exhaust emissions requirements that all small engines (less than 25 horsepower) had to meet. As a result, small engines became much cleaner – in some instances small engine exhaust gas emissions were reduced by up to 90 percent. In all, EPA estimated these initial regulations would reduce emissions by 32 percent, eliminating almost 35 million tons of pollution and saving nearly 220 million gallons of gasoline though 2020.
In the early 2000s new ARB and EPA regulations again reduced small engine exhaust emissions by lowering exhaust limits and requiring engine-life durability testing. EPA estimated that the new rules would further reduce emissions from small engines powering ground-supported equipment, such as walk-behind mowers and lawn tractors, approximately 60 percent, and reduce fuel consumption an additional 15 percent by 2027. EPA also estimated the new rules would further reduce emissions from handheld equipment, such as string trimmers and chain saws approximately 70 percent, and reduce fuel consumption an additional 30 percent by 2027.
The third, and most current, stage of regulations was phased in though the late 2000s. This stage included additional emission reductions for engines powering ground-supported equipment, as well as the introduction of evaporative emission controls for other small-engine powered equipment.
And we’re not done yet
Small engines are now regulated on a global level. New emission regulations in Canada, Europe, China, and Australia will be effective soon. And manufacturers continue to work with the California ARB and EPA as they work to implement regulations on future small engine emissions. As a result, manufacturers continue to look for ways to improve the efficiency of the small engines they make to benefit both consumers and the environment.