Electric lawn mowers are great because they are free of noise and exhaust. However, electric mowers are not perfect.
Battery powered lawnmowers are expensive, take time to charge and can be as heavy as petrol mowers.
Power cord electric lawnmowers are light and cheap but dragging around a cord
is inconvenient and dangerous.
So I propose a wirelessly powered lawnmower. The lawnmower would be inductively powered by an array of solenoids which are buried just below the surface of the lawn.
Each solenoid would be a discrete element inductively coupled to adjacent solenoids (i.e not physically connected). The solenoids would be embedded within plastic shells to prevent corrosion. The shells could be shaped as rocks for aesthetics.
A source of alternating magnetic field would be provided in a relatively safe place (e.g. underneath a path near the lawn). This would be safer than all the solenoids being electrically connected and would also make installation relatively easy.
This system could be used for hand pushed or robotic lawnmowers. A similar system could also be adapted for household vacuum cleaners.