Do I have the right under Australian Consumer Law to know why the solar production is 0 for 3 months from my energy supplier, and whether my house is using more energy than my solar panels can produce at a given date? Who do I ask?
Have you contacted your energy service provider (the one who gives you the discounts/rebates) and asked them to provide you with a detailed breakdown of how much energy you are consumer vs. how much you are producing? Also, you can try calling the company from whom you bought the panels from, perhaps they can shed light on the matter. Has your panels every produced solar energy or has it appeared to have stopped in the past 3 months?
If you get nowhere with the above contacts, you can try contacting the Energy and Water Ombudsman Victoria. They are an independent agency that oversees service providers in the energy and water sector in Victoria. They offer a free dispute resolution service to consumers who have problems with their energy service provider. However, do note that the process takes some time as they have their own internal dispute resolution process and may be overwhelmed with complaints at times.