Think of greenhouse gas emitters, and images of power plants and long lines of running cars come to mind. Actually, many smaller engines contribute significantly to pollution and global warming. The federal Environmental Protection Agency has been moving closer to tightening restrictions, say, on the 30 million lawn mowers operated weekly in this country.

That makes the work of the Akron-based Hydrogen Energy Systems all the more promising. On Monday, the city announced that it would purchase 20 golf carts from the start-up to be deployed at the city’s golf courses.

The new thing about the carts is the technology developed by HES, a mixing block that replaces the fuel injector or carburetor in a small internal combustion engine, allowing for a blend of gaseous hydrogen and air to deliver the power.

Jeff Wilhite, the company’s chief executive, has explained the strategic progression, building from golf carts to other engines of 30 horsepower or less. He talks about tow motors as the next frontier, then perhaps scooters and even those mowers. Right now, the company will benefit from the platform the city has provided to prove its technology. Here is an example of the public sector playing an indispensable role — a timely catalyst in moving from idea to the marketplace.