Hitting environmental targets

Large corporations are consistently being challenged to adopt ground-breaking social responsibility and environmental policies. Engineering and technology experts Siemens put these philosophies into practice by using its own products throughout its estate, achieving impressive energy-savings as well as outstanding working environments for the company’s employees. But to take the leap from manufacturer to end-user, Siemens employed the help of Andromeda to provide integrated control solutions for their building services; offering the missing ingredient for realising a green, sustainable development.

Acting in a responsible way is placed at the centre of Siemens’ operations, representing one of three core company values. Environmental concerns form a large part of this ethos of responsibility, both in terms of striving to develop environmentally innovative products and services, as well as considering the impact on the environment made by the organisation itself. Siemens Real Estate plays a key role in honouring this commitment by ensuring that the company’s own buildings put into practice corporate benchmarks, placing Siemens’ own products at the centre of building services solutions. The 2007 development of a new UK HQ in Frimley, Surrey, gave Siemens the opportunity to demonstrate its innovative practices and solutions and create a commercial office space exemplar.

Sir William Siemens Square is a stand-alone site with four office buildings totalling 183,000 ft2 (17,000 m2), providing offices for 1,400 Siemens employees (who were previously housed in offices in Bracknell and Staines). Andrew Beshaw, Managing Director of Siemens Real Estate, who led the relocation project said: “Our aim was to create an inspiring, environmentally friendly, modern working environment for our employees, helping them to work to their highest potential, productively and in comfort.”

“The relocation of our UK headquarters gave us an ideal opportunity to rethink the way we work and massively reduce our impact upon the environment” said Beshaw. Siemens’ key drivers therefore included legislative and energy-saving benchmarks and the creation of an outstanding working environment for their employees. The move also provided a vehicle for creating a showcase of Siemens’ own technology, with the product portfolio working as a practical demonstration producing tangible results. In this way the Frimley HQ actively portrays the journey from Siemens as manufacturer to Siemens as end-user. But in order to achieve this, Siemens enlisted Andromeda, master integrators of intelligent building solutions, who helped the organisation realise its vision for the new site.

Enhancing the services

As part of the refurbishment of the site, Siemens aimed to significantly enhance the existing building services as the campus had very limited control functionality and was considered well below today’s standard for a corporate HQ building. As Siemens’ partner in the project, Andromeda provided an integrated control solution covering lighting control, dynamic façade control, emergency light testing and monitoring. Vitally, this solution utilises Siemens KNX products, and integrates with the Siemens Desigo HVAC control system via the PX/KNX controller.

A significant proportion of Siemens’ global carbon footprint is due to electricity consumption. It has been well documented that a large portion of a building’s electricity consumption is due to inefficient lighting. A dynamic lighting control strategy was therefore crucial to the company’s plans for the site.  

The lighting control system supplied by Andromeda is a KNX/DALI system utilising DALI ballasts from OSRAM (a Siemens owned company) within all of the DALI luminaires. At the centre of this control system is the KNX/DALI gateway from Siemens housed within the Andromeda control panels.  This DALI gateway allows digital communication direct to each luminaire for switching, dimming and feedback. Intelligent KNX presence detectors from Siemens are connected to the KNX bus for local control. The state of the art presence detectors truly recognise when a building or room is occupied, performing over and above the traditional ceiling mounted PIRs that very often switch off lighting when people are still in the room.

The Siemens presence detectors also perform constant light control, or daylight dimming as it is often called. A design level of illuminance of 400 LUX is maintained at desk level by measuring reflected light beneath the presence detector. The lighting control group is then dimmed by the system to maintain the 400 LUX setpoint. This control strategy is carried out gracefully over a time period to avoid any sudden changes in light level that may draw people’s attention to the lighting. In terms of energy saving, it can generally be seen that a 50% energy saving can be achieved by dimming the lighting load by around 50%. During a reasonably bright day a dim value of this amount is not noticed, and the design level of illuminance is maintained on the desk. This dynamic mode of control is used throughout the Frimley site and is saving around 60% of the lighting electrical load per year.

The lighting control system also provides the functionality of emergency light testing and monitoring, as well as supporting the maintenance operations by providing lamp failure reports.

Building intelligence

For cellular offices and meeting rooms there is manual override provided by an intelligent Siemens KNX push button with glass frame and integrated room temperature controller for the local fan coil unit control. With this push button you can switch, dim and set your lighting to a required level, along with controlling your electric window blind. The four buildings at Frimley are principally glass clad from floor to ceiling as many modern office buildings are. This design concept is excellent for daylight dimming control but can be problematic with regards to solar gain and glare. To resolve this problem Andromeda supplied and commissioned automatic solar reflective blinds on all façades. The blinds are high performance with metallised reflective material to deflect the solar gain and reduce the load on the cooling during the summer months. This reduction in load results approximately in a 40% reduction in electricity consumption. The blinds are controlled via a central weather station over the site-wide IP network.

Andromeda’s solution also provides integration via the Siemens Desigo system, which allows the maintenance team to monitor and analyse the performance of the building over time. Over one year after the move into their new HQ, Siemens has been doing just that, with electricity consumption reduced by 52% compared to that at Bracknell. Beshaw says: “These savings are largely attributable to the lighting control and façade control solutions integrated by Andromeda using Siemens’ products.”

Going green

Highlighting the responses of its Frimley-based employees, Beshaw says that it took time for people to get used to the green measures that the system put in place, such as the blinds moving independently. As the refurbishment evolved, it became important to reach a compromise between the energy-saving system and the individual’s need to feel in control over their environment, meaning that certain local control measures were included in the solution. Vitally though, Beshaw feels it was crucial to stand by a system that may seem radical to people at first, as innovation takes time for people to adapt to. He states: “Staying true to the system’s capabilities is why we have achieved such substantial energy savings.” 

Within its Frimley HQ, Siemens has been able to create an enviable working environment, a showcase for its own products, and save substantial amounts of energy by investing in integrated control solu
tions from Andromeda. As this remarkable project shows, a real commitment to environmental responsibility gets real results.