CASE STUDY | EDGE SUEDKREUZ Exposed timber beams on the ofce oors support the concrete deck of the oor above The fire brigade is very sensitive when it comes to electric cars because it still doesnt know the best way to handle them Martin Elze the Carr Building to its smaller sevenstorey sister, the Solitaire Building. This can accommodate up to 218 cars and 300 bicycles. It incorporates an automated parking system to save space by doublestacking parked cars one above the other. Impressively, all the parking spaces incorporate electric charge points. Unfortunately, the citys electrical infrastructure did not have the capacity to power the building, its kitchen, the building services and to simultaneously charge more than 200 electric vehicles. The building had a 7.5MW electrical connection, the maximum available. If everything in the building is running, its total electrical demand is predicted to be 6.8MW. Electric car charging adds another 1.5MW, taking total demand over the 7.5MW maximum. For 99% of the time, electrical demand is not an issue, but when the building is fully occupied, its lunchtime so the kitchen is running at full capacity, and its 40C outside and the sun is shining, then we may need to act, Elze says. In response, the BEMS constantly checks electrical demand. If it does start to come close to 7.5MW, then the building automatically starts to reduce the charging rate for the cars. We had to introduce some load management, so that on the rare occasions when everything is running, the car chargers will only charge at part speed, Elze says. Interestingly, the basement is the only part of the building to have sprinklers fitted. The fire brigade is very sensitive when it comes to electric cars because it still doesnt know the best way to handle them especially an entire car park full of them which is why they have insisted we put in sprinklers, says Elze. Alongside the electric cars, bicycles and sprinkler tanks, the basement also houses Drawing showing the MEP corridor two combined heat and power (CHP) engines. We wanted to connect to the district heating in the city, but heat is still produced using coal in some parts of Berlin, so Edge decided to use CHP engines running on biogas to provide all of the buildings heat and additional power, explains Elze. Clearly, sustainability and occupant wellbeing are important drivers for the Edge Suedkreuz. The designers innovative response to these imperatives has resulted in the building being pre-certified Platinum by the German Sustainable Building Council and pre-certified Well Gold. CJ 78 November 2022 www.cibsejournal.com CIBSE Nov 22 pp74-76, 78 Edge Berlin.indd 78 21/10/2022 16:47