My bill only has a small solar income -why this? Is my system not working properly?
It is possible that your solar system is working well. Your electricity from your solar power system is first fed into your house and then your meter only captures the excess that is not used in your home and exported to the power grid (electricity lines).
So your 4kW system for example generated 1200kW/h in three months (as shown by the inverter monitoring /reading), but your Net meter shows only 300kW/h sent back to the grid. For each kW/h you get 8cents so your solar income will be $24. That relative small amount shows up as a credit on your bill. But don't forget the 900kW/h your system generated and you used in the house. You saved to purchase this electricity from the electricity provider. Let’s say if you are on a flat electricity charge of 30c per kW/h you will have saved $270, which you would have paid if you would not had your solar power system. So your total solar system electricity for that quarter is worth $270 + $24 = $294, even though your bill only showed a $24 income.