With the save the world ideology going around, would you be more inclined to hire a company that was dedicated to this approach? Following a discussion with a local Co-operative extension agent this idea started growing. Looking at equipment possibilities, even thought about putting solar panels on the truck to help push the idea.
To be blunt (hang in there, there's some positive follow up...), "Zero Emission" lawn care service is BS, it's just magic marketing words with zero meaning. And in terms of opportunity cost (diverting from meaningful action), it may be a net negative.
Demonstrated by
"putting solar panels on the truck to help push the idea.". If one is serious about being 'green', a truck is one of the last places you'd put a solar panel (OK, maybe better than trying to build them into roads). A solar panel should be placed where it will be in the sun all day, at the best angle to capture the most energy possible. Putting it on a truck just wastes that potential - you might not even ever recover the energy used to make the thing, so it could be a net negative (though opportunity cost is very real as well). The weight and air drag of that panel will lower the MPG or "MPGe" of the vehicle, wasting more energy that could be used by the equipment. It's a stupid idea.
OK, the positive - If by "zero emissions" you mean battery powered (which is NOT zero emission, it just moves it to the power plant), well, there is a good case for it. Those small engines used in lawn equipment put out a lot more pollution than a modern car (esp hybrid). Cars can afford cat converters, fuel injection, computer control, variable vale timing, etc. Those technologies do not scale down to a small engine. So I do believe (that unlike EVs), replacing these small engines with batteries is a good move for the environment, because the small engines are so bad. Even a fossil fuel plant, coupled with losses to the battery, will be cleaner than that lawn equipment.
But labeling it "zero emissions" is BS, and I wouldn't trust any business that tried to pawn that scam off on me, and that had solar panels on their truck as some sort of "virtue signalling".
That said, most people haven't looked into it at that level, and fall for the virtue signalling hook-line-and-sinker, so as a business move, it could work. I'd prefer the business be honest about what they are doing, as there still is an advantage - why be manipulative about it?
-ERD50