Most people would respond that "Reverse Metering" is good and I'd go along with that view. I also decided that it was theoretically not so difficult and I was happy with my point of view until someone inserted a bit of reality.
It is being done so the mechanics of the problem are known. There is a lot of scope to get it wrong but that is eliminated in the USA (for instance) by having to get the system inspected rigorously by inspectors before commissioning. I know it involves pure sine wave inverting. Go to any site selling inverters and compare modified sine wave inverters to pure sine wave inverters and you'll see that pure sine wave inverters are at least 3 times more expensive and that is before the synchronizing problem is even tackled. At the level of small turbines of less than 1 KWatt I would think it would be virtually impossible to make it worthwhile from anybody's standpoint ie the utility or the private generator.
However, and this surprised me, the mechanics of the process are not the biggest problem. There are three problems that I can remember - there are more.
The first concerns grid maintenance. In the conventional system that excludes reverse metering when a switch is thrown everything below that switch is isolated and can be worked on. With reverse metering that no longer holds and maintenance becomes difficult and where an end node is not obvious virtually impossible. There are ways around this problem and they are all expensive - for instance duplicate lines. This topic is the subject of major research and for new distributions new workable solutions could be designed into the system. Not easy.
The second is costing. By and large the biggest problem facing a utility is matching power production to power consumption with the production exceeding consumption by the smallest margin practicable. The excess production is lost and the costs involved are simply part of the production costs. However with Reverse Metering the utility is forced to "repurchase" any and all production by the private generator - this is not fair on the utility. The private generator suffers no losses due to overproduction and is not fair "competition" to the utility. One supposes that somehow the utility could control when it will repurchase - another level of complexity !?
The tail can wag the dog. If the utility is not many times stronger/more dominant then the sum of private generation then the utility cannot predictably make production slightly exceed consumption and essentially control is lost over the grid and can lead to massive under-production, a very disagreeable situation. Incidentally it can also lead to massive over-production and who would foot the bill ?
For these reasons alone it is already obvious that although desirable it is simply not simple. I'm not sure that if I represented the utilities I would allow it at all and paradoxically I'm firmly on the side of the private generator.