Solar panels begin to show a return on your investment when they produce more energy than you’re using, or that you can store. Since the start of 2020, energy suppliers have been obligated by law to pay households for any energy they export back into the grid. This is known as the Smart Export Guarantee and since you don’t have to sell your excess energy to the same provider you get your current electricity supply from, it’s worth shopping around for the best rate per kWh of energy you produce.