SIEMENS

Buildings literally gobble up energy. In fact, energy expenditures account for around 40 percent of a building’s total operating costs. All in all, buildings are responsible for 40 percent of primary energy consumption worldwide and around 21 percent of greenhouse gas emissions (see feature “Sustainable Buildings”, Pictures of the Future 2/2008). But the potential for savings is also considerable. “Lighting accounts for 19 percent of total electricity consumption worldwide,” explains Peter Dobiasch, a specialist in professional lighting systems at Siemens’ Osram subsidiary. “The use of more efficient lighting systems across all forms of light source would reduce power consumption by a third.”

Even greater savings can be achieved when energy sources and energy consumers are optimally harmonized. That’s just what the Siemens Building Technologies division (BT) is now doing in partnership with Osram. An optimized configuration in an office building might look like this: a presence detector to recognize if anyone is in the room; an air-quality sensor to measure the CO₂ level - if no one is there, lighting and ventilation can be switched off; a dimmer system with a brightness sensor to determine how much, if any, artificial light is required; sun blinds and louvers that automatically track the course of the sun so as to let in the optimal amount of daylight; and a temperature sensor to measure heat input so that the system can determine whether a combination of increased shade and artificial light would be more energy-efficient than turning up the air conditioning. “Smart algorithms are used to calculate which mix saves the most energy,” Dobiasch explains. “A building can achieve savings of as much as 50 percent. Today, Siemens is the only company offering such a holistic system for reducing energy costs.”

In fact, as Dobiasch explains, Siemens even guarantees that its predicted energy savings will be achieved. “The investment pays off - as a rule, within two to five years,” he says. Siemens offers a special contracting service in this field. Once engineers from Siemens and lighting designers from Osram have analyzed a building’s requirements, the company will provisionally finance the installation of the new technology. This means the customer doesn’t have to pay up front but can instead amortize the investment by means of annual savings in energy costs. To date, Siemens has completed over 1,000 such projects worldwide, with guaranteed savings of €2 billion and a reduction in CO₂ emissions of 1.4 million metric tons.

Joint projects of Osram and Siemens BT include the installation of an integrated building management system for the extension of the 100,000-square-meter Vancouver Convention Centre in Canada. As a result, the building has received gold certification of its fulfillment of the Leadership in Energy and Environmental Design (LEED) standards. This U.S. rating system awards points for low energy consumption, green building design, waste reduction, and reduced CO₂ emissions. The Vancouver Convention Center has a 2.5-hectare green roof that will help make the building completely CO₂-neutral from 2010 on.

In early 2010 the Munich headquarters of newspaper publisher Süddeutscher Verlag, with office space for 1,850 employees, was also awarded the gold LEED certificate - the first office building in Germany to receive this honor. This client’s specifications were stringent, including energy efficiency and an optimal working environment, but also flexibility to accommodate different users and potential tenants. The solution was to install an innovative building automation system from Siemens along with individual room control systems featuring presence detectors, so that lighting can be switched off or dimmed when less light is required. In addition, an electronic system provides an optimal mix between a geothermal heat pump, power consumers, incident solar radiation, and ventilation, thus maintaining ideal temperatures in the building without having to draw on the municipal district-heating system.

“Osram and BT have a lot more ideas for the buildings of the future,” explains Tobias Huber, Head of Lighting Business Development at BT. In the event of a hotel fire, for example, the following scenario would be possible: Presence detectors register which rooms are occupied and room lighting is activated to wake the occupants. The blinds are automatically lifted so that access to the windows is not blocked. At the same time, the lighting system is switched to an emergency power supply, lights illuminate the escape route in the halls, and presence detectors help rescue workers locate injured persons.