Resource hub Funding Watch Feed-In-Tariffs Export tariffs are additional payments if your installation is hooked up to the grid for any surplus energy you generate and feed/sell back into the grid. The tariff per kWh is determined based on the size of the installation, the Energy Performance Certificate (EPC) rating of the building, and installation date. Tariffs are generally updated quarterly. Payments are made for 20 years. Public and private sector organisations. Amount: Variable. Find out more.