If I produce enough power will my provider give me a cheque back?

Rarely. With today’s low feed-in tariffs, most households won’t earn more from exports than they spend on power and daily supply charges. Some people on old premium schemes still receive credits, but those schemes are closed to new customers. What solar and a battery can do is cut your bill substantially by covering much of your own use. If your account does go into credit, your retailer usually carries it forward or can refund it on request. How much you save is subject to many factors such as usage, tariff and system size.