Reply #21: Cats eventually die

[Daedelus76]

They wear out. Then you get more pollution.

Much better idea would be to encourage houses with smaller lawns or rocks instead of grass. Then spend money on researching direct injection for small gasoline engines, so that you can eliminate the need for catalytic converters.

Companies lik Piaggio/Aprilia already have small 5-7 hp 2-stroke engines they use for motor scooters. They have no catalytic converters, they use a computer to time the injection of fuel directly into the combustion chamber. The result is less pollution than many 2-stroke and 4-stroke engines that use catalytic converters, but there is still an economy of mechanical efficiency. They meet the Euro 2 vehicle emisions standards.