An expert in solar energy has told me some interesting facts about the price of power.
Consumers typically pay 30c per kwh. Of that about 5 is the wholesale cost of the power (the price retailers pay for the power). 15 cents is line charges (the cost to get the power from the generator to the consumer), and the other 10 cents is the margin received by the electricity retailers.
When a person with a solar system sells their surplus power to the “grid” they are actually selling it back to the retailer, and receive 6 cents (or roughly the price retailers pay the generating companies).