It depends on how much your electric company will pay you for excess energy production. Currently you may get a good rate, but as more people install solar panels that rate is going to get worse, as it gets more expensive to deal with all the homes with solar. So figure out what the deal is in your location, don't get a battery until you need it. I Don't know, but I realize in the future if Austin Energy doesn't pay well for excess production I will.
You can also size your panels such that you never produce excess energy but you will be leaving a lot of roof space that could be making energy to waste. A sunny winter day still makes a ton of energy.
You can also size your panels such that you never produce excess energy but you will be leaving a lot of roof space that could be making energy to waste. A sunny winter day still makes a ton of energy.