The European Commission has published good practice guidance to help implement the EU's Energy Efficiency Directive. The Directive requires individual measurement devices, 'heat meters' or 'heat cost allocators', to be installed in buildings that contain several apartments or are multi-purpose and which are supplied with heating, cooling or hot water from central or collective systems. Known as 'sub-metering', this system allows individual consumers to pay for their own consumption. As a result, it tends to stimulate behaviour that is more energy efficient and creates substantial energy savings for the building as a whole. This new guidance advises national authorities and building owners and managers on how to determine which buildings may reasonably be exempt from the Directive's requirement for sub-metering because it could not be installed in a technically feasible or cost-effective way.
Sub-metering can be used to save energy alongside other means of improving the energy efficiency of buildings (for example, by installing better insulation or heating systems).
After initially being published in June 2016, the guidance has been refined and elaborated following a series of workshops with representatives of national authorities and stakeholders. It also discusses how best to take into account both individual occupants' energy consumption and the energy efficiency of buildings as a whole when billing consumers: this is known as 'cost allocation'. Cost-allocation rules that are seen as fair and transparent by occupants are critical for the smooth introduction of sub-metering in buildings where energy bills were previously calculated using different criteria, e.g. in proportion to the share of the building's total floor area occupied by the person paying.