The installation by Aimteq of wireless BEMS (building energy management systems) at market-leading public transport provider, Stagecoach, has seen aggregate gas savings across 24 upgraded depots of 20.45% based on regression, and 17.15% based on year-on-year consumption data. Moreover, using the latest savings data, the investment is set to achieve a return of less than two years on a region-by-region basis.
In 2015, Stagecoach launched a new sustainability strategy that included a plan to cut carbon emissions at its transport operations in the UK and North America. Produced in partnership with the Carbon Trust, the ‘Shared Responsibility, Shared Future’ strategy includes aims such as reducing the carbon emissions from buildings by 7% by April 2019.
Within the UK Bus division, this target alone will demand a total capital expenditure of around £1.3 million, and will be focused on lighting, heating, ventilation and air conditioning, as well as behaviour change and monitoring. However, it is expected to deliver cumulative cost savings of £4.7 million by the time of its completion.
“BEMS is one of several initiatives that we are implementing to help meet our carbon reduction target in buildings within the UK Bus division,” states Graham Whitelocks, director safety, health & environment at Stagecoach UK Bus. “Previously, our depots relied on basic heating controls and we felt there were significant gains to be made by switching to wireless BEMS.”
The wireless aspect of the solution was deemed particularly important considering the environment of a typical bus depot.
“Our bus depots generally comprise large structures and in some cases the sites have more than one building, so going wireless is very cost effective as there is no need to pull cables across buildings,” explains Mr Whitelocks. “Wireless is quick and easy to install without causing any disruption to our staff or operations. In addition, a wireless system is much easier to amend as depot requirements change.”
Fully wireless energy management
WEMS, a fully wireless energy management system, and Aimteq, a leading systems integrator experienced in WEMS technology installations, proved to be the perfect fit. As WEMS sensors are wireless and discrete, they can be installed during regular working hours. This means no overnight labour and no costly shut-downs. Sensors can be installed in a matter of minutes, with no cables to run, no ceilings to cross or holes to drill.
“Another reason we opted for the Aimteq/WEMS solution was the bureau service, which meant we could delegate the controls to an expert who could remotely optimise energy consumption across all sites on an ongoing basis,” says Mr Whitelocks. “Leveraging a bureau service would remove the need for an in-house BMS expert at every depot.”
Duly convinced of the benefits on offer, Stagecoach first ran a pilot at its Barking (East London) and Worksop (Nottinghamshire) depots during the 2014/15 heating season.
Following the immediate success of these installations, a further 22 depots have since been upgraded across the country. To date, the WEMS system has been installed in the London (seven depots), East Midlands (eight depots), Manchester (six depots) and Liverpool (three depots) regions.
“There have been no disruptions to daily operations, allowing our staff to continue with their work during BMS installation,” says Mr Whitelocks.
Each system controls the depot’s gas heaters and boilers, maintaining the temperature in the workshop area at an agreed set point of 16°C. In fact, heating is matched to the occupancy at each depot for both normal working days and weekends. Another feature sees the heating system connected to the workshop doors, allowing the heating to be turned off when the doors are open.
Importantly, the bureau can remotely change any parameters, such as timing schedule or temperature set point, at the request of Stagecoach.
“We have a partnership-based relationship with Stagecoach,” states Vipul Palan, business development manager at Aimteq. “We go far beyond what is expected of a ‘regular’ system integrator, working together closely on a strategic level to ensure carbon reduction targets can be met. The bureau service offers a ‘centralised control’ concept that allows us to implement a consistent heating strategy across all depots, in liaison with Stagecoach. This ensures ideal environmental conditions for staff while reducing the risk of heating being left on during non-operating hours. Where requested, we have installed ‘view only’ access to the WEMS system, allowing depot managers to monitor gas consumption and temperature profiles within the workshop.”