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How to calculate heating bills in an apartment block

Topics: Billing

While most new apartment blocks have communal heating systems with meters providing accurate data for each home, what can be done about older buildings?

An efficient way to provide heat to an apartment block is through a communal heating system. This provides independent heating and hot water to each residence, negating the need for each dwelling to have a flue, gas supply or additional ventilation.

Communal systems integrate easily with renewable energy sources and are more efficient as they dramatically lower kW loading compared to separate boilers. Usage is measured by a meter in each home, which can be monitored remotely for billing and management. The system can also be serviced easily without the need for visiting each resident and as a result are becoming increasingly popular with UK energy users.

Converting existing buildings to communal heating systems can be expensive. This is when sub-metering can help by providing a way to collect live data, enabling the property manager/landlord to send tenants regular and accurate bills. This information can then be used to understand why and where energy performance is poor, you can then find ways to improve it.

Below are two common methods of sub-metering…

Heat energy meter

This is a device which consists of a flow meter of heating fluid, two temperature sensors and a calculator which converts the consumption into kilowatt-hours (kWh). Metering devices need to be installed into every apartment, while the individual heating costs are calculated by combining the cost of heating the apartment and the communal areas.
The benefits of this system include measuring consumption in kWh units and splitting costs for each apartment is straightforward. However, this system requires two-pipe heating systems and only measures the overall heat consumption of a flat, not single rooms.

Heat cost allocator

These electronic devices are installed directly onto the majority of radiator types and detect the heat output of each radiator in the apartments. Bills are calculated by dividing the total cost for heating of the building proportionally to the measurements of the allocators. Another benefit is that data collection can be done remotely, without the need to visit each apartment.

Benefits of sub-metering

Both these types of sub-metering are good options for primary metering where it is not possible to interfere with existing meters. It can also help with producing accurate Display Energy Certificates, an annual requirement for public sector buildings of more than 1,000 square metres, and for the annual CRC energy efficiency reporting.

Here at ista, we’re experts in ensuring heating costs are distributed fairly with everyone only paying for what they consume. Whether it is at the apartment heat meter or our innovative heat cost allocator (radiator) meter, we calculate each tenant’s bills and ensure regulatory compliance.

Our systems deliver a flexibility to match your organisation and allow your tenants to receive their bills in a number of convenient forms. We give you confidence and transparency in the full settlement of your community or district heating across your buildings and whole estate.


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