British Land saved £45,000 in the first year and expects to achieve payback in 18-24 months.
Back in 2009, British Land’s trialled an AMR metering system at its Head Office, York House, which is situated in London’s West End. The building offers over 8,400m2of office space, of which British Land occupy 3,700m2. An important aspect of the project was to learn from the experience and assess the potential for a wider roll-out across its property portfolio.
Challenges & Actions
The main aims of the AMR metering solution were to achieve more accurate utility billing and occupier on-selling, as well as improving energy management to help reduce CO2 emissions from the building.
As a result, British Land developed a metering strategy which included the replacement of the main utility electricity meters and installation of an additional 6 sub-meters, including the re-commissioning and connection of approximately 50 sub-meters pre-existing sub-meters to an AMR systems.
The sub-metering comprised:
- Sub-metering of each occupier’s demise. This measures the total amount of lighting and small power to each occupier’s demise
- Sub-metering of common services: heating, ventilation and air-conditioning
- Sub-metering of common parts: lighting and small power.
- In addition the system received gas and water data through pulse pick-ups.
The meters transmitted data at 15 minute intervals via a hard wired communication line direct to a central server communication network in York House. The data is then transmitted from the server to their external service provider, EP&T via ADSL every four hours.
The external service provider undertakes off-site data analysis to identify any issues/anomalies in the patterns of energy consumption, and to indicate potential energy and cost savings which can be made through appropriate energyef ciency measures which are then reported to the on-sitebuilding engineering team. With a detailed knowledge of what equipment or BMS setting each sub-meter is measuring it is often possible for the service provider to indicate to British Land engineers which piece of equipment or BMS setting is causing a problem.
Each month British Land receives reportwhich highlights the nancial impact of actions completed, aswell as providing an on-going record of outstanding actions. The offsite team also have a short teleconference each month with the site team to discuss the report and have technical discussion to consider solutions to more complex problems.
Critically, the service provider guarantees a minimum amount of cost savings in common parts and central heating and cooling plant. The service provider’s ‘top-up’ guarantee is applied to York House as well as a number of other British Land buildings which relies on the offsite monitoring team finding enough operation savings through the process described over a 3-5 year period to ensure that the building’s consumption in these areas is reduced by approx 10%-12.5% against a baseline year set before the service was introduced.
The service provider also supplies a statement for each occupier’s energy bill which the managing agent then uses to produce an invoice for each occupier.
Lessons & Results
A significant benefit of the metering system is how it has helped British Land engage with their occupiers. British Land uses metering data to individually review with each occupier their contribution to the overall energy use in the building, and to discuss how to make savings. Metering data is then also used to demonstrate improvements and savings over time. The AMR software is web-based and can be accessed by occupiers and owner alike on a shared license to provide real transparency and data sharing between the two.
Overall, British Land has invested approximately £65,000 in installing the metering system, and there is an on-going cost of approximately £12,000 per year for maintenance of the metering and off-site analysis and reporting.
This has helped optimise the heating and cooling system (including prompt identification of a broken sensor that had been causing constant gas use for heating and re-programming of the Building Management System to introduce economy cycles and new deadband set points for cooling).
As a result, BritishLand saved £45,000 in the first year and expects to achieve payback in 18-24 months.
