Requires suppliers of energy (electricity, gas, heating oil, LPG, heat, refrigeration) to meet government-mandated targets for energy savings achieved through the suppliers residential and tertiary customers. The energy savings certificates (CEE) scheme is based on a three-yearly obligation to make energy savings under CEEs (1 CEE = 1 kWh cumac61 of final energy). The third period (2015-2017) had a target of 850 TWh cumac for the period, of which 150 TWh cumac is for households in fuel poverty. The fourth period (2018-2020) increases the CEE target for the fourth period (2018-2020) to 1 600 TWh cumac, of which 400 TWh cumac is for households in fuel poverty.