You get a FIT rate for the power you do not use, there is no 3p back to you. If your meter is going backwards when you generate you are not storing it on the grid, you have a meter with no back stop.
My guess is the certification date on that meter is mid to late 80's in which case it's probably not been recording properly for a long time anyway. Life span of a mechanical meter is 20years. Meaning the meter most likely will have been under reading (meaning your Kw's have been shorter than they should be the reverse direction of the meter when feeding back will have added to this degradation)
My guess is the certification date on that meter is mid to late 80's in which case it's probably not been recording properly for a long time anyway. Life span of a mechanical meter is 20years. Meaning the meter most likely will have been under reading (meaning your Kw's have been shorter than they should be the reverse direction of the meter when feeding back will have added to this degradation)