Or just do it the better, manual, way - point a heat lamp and fan at it with the unit open. Even if you melt the ice inside, you still need to remove the moisture. The manual process is not that intensive and needs to be performed very infrequently.
But how about this, maybe something that keeps an eye on the state and rate of ice buildup, and helps schedule doing it when it's actually necessary, and maybe helps spot issues that cause quicker buildup.
That could be useful. An easy implementation might to to track temperature trends with power draw relative to the other units. You might have to account for door openings, but seems like a good way to mark units for mechanical inspection.