Transport for London (TfL) has run a trial using Wi-Fi sensors to collect data on the occupancy of its buildings and to optimise the ventilation, air conditioning and heating.
A year-long pilot has taken place at its Stratford office and the initiative is now being extended to other sites across the TfL estate.
It worked with smart tech provider LightFi to collect live, privacy protected data on the number of people in the building, rather than generally ventilating the whole building during office hours. This involved installing five sensors on each floor to pick up secure Wi-Fi signals from mobile devices used in the building.
Responding to real time occupancy data, the central air handling units (AHUs) within the building reacted to instructions to reduce air flow - and in turn the electricity used for heating and cooling - while maintaining the quality of indoor air during periods of lower occupancy.
Energy and cost savings
This has led to a prediction that the approach will reduce the total energy used by 12% at the Stratford office building, saving the equivalent of 140 tonnes of CO2 emissions annually - as well as £182,400 in annual operating costs. In the long term, this will extend the lifetime use of building equipment and generate even greater savings with the reduced need for maintenance and repair.
The commissioning trial ran for a year to ensure the system was fit for different seasons, and TfL said that additional wireless sensors monitoring levels of carbon dioxide, temperature and humidity in the building also ensured a comfortable working environment.
The technology has now been introduced to the Pier Walk office in North Greenwich, with plans for installation at the Buckingham Palace Road office in Victoria and Palestra in Southwark to be completed in the first half of this year.
Similar percentages of cost, carbon and energy savings are expected when this technology is installed at those buildings.
Early adopter
Lilli Matson, TfL’s chief safety health and environment officer, said: “We’re pleased to be an early adopter of this smart innovation that we trialled at our Stratford office and are now extending to other buildings in our estate.
“It will help us to cut carbon emissions and save cost and energy without impacting operational performance and staff comfort. We are doing our part on our estate to help achieve the mayor’s goal for London to be a net zero carbon city by 2030.”
