When you install a solar system, as the owner of the system you generate renewable energy certificates called Small Technology Certificates (STC). Each STC equates to 1 Megawatt hours (1000 kWh) of energy your system can produce in the period to 2030 up to a maximum of 15 years. Solar System retailers apply for these STCs on behalf of the consumers and provide you discounts upfront, thereby reducing your initial investment cost substantially.