‘Climate protection is our job’

Climate change, energy transition, gas crisis – energy and sustainability are the topics of the day. How are these developments affecting building technology and the real estate industry?

Let me start by saying that our employees are already contributing to climate protection on a daily basis. For example, every old boiler that is replaced with an energy-efficient system, every heat recovery system we plan and build into ventilation systems, and every operational optimisation carried out by our FM colleagues reduces CO2 emissions and conserves resources. What is new is the increased public interest in climate protection for existing buildings, partly due to the current gas shortage. This is not surprising, given that around 35 percent of total energy consumption in Europe takes place in buildings. The energy transition is a Herculean task overall. As building technicians and facility managers, we can make a significant contribution to its success. So we are all an essential part of the solution through our jobs. Personally, I find that highly motivating.

Where do you see the decisive levers in the traditional trades of heating, cooling, ventilation and electrical engineering that can be used to reduce energy and CO2 in buildings most quickly, say by at least 15 per cent?

There are simple things, such as lowering the room temperature when heating, significantly reducing heating, air conditioning and ventilation, and even switching them off outside operating hours, and much more. This alone brings significant savings. And there are technical measures, some of which require investment and for which we, as building services engineers, are in demand. I will list the most important ones. Adjust the hydraulic balance. Here you need to check whether there is sufficient ‘spread’, i.e. the temperature difference between the flow and return. In the cooling range, this should generally be 6K, and in heating mode between 5 and 30K, depending on the heating consumer. Old heating pumps, known as constant speed pumps in the control circuits, should be replaced as a matter of urgency with regulated automatic pumps. It is important to ensure that the new pump is not oversized, otherwise even the latest pump will run at poor efficiency. Incidentally, this and many other measures are subsidised, with the government covering up to 35 per cent of the costs.

In general, sustainable planning of conversions and renovations. Here, it is important to find the right system concept, lower the system temperatures and opt for new heating systems such as a heat pump in combination with solar technology.Increase the heating surfaces in existing properties so that lower temperatures can be used in winter. To do this, we literally go ‘to the ceiling’ and work with heating and cooling ceiling elements.And last but not least, the building automation in the property must be optimally adjusted. In addition, I recommend using an intelligent self-learning system in larger buildings, such as Recogizer. The investment is relatively low and can bring further savings of around 20 percent. This makes particular sense where the physics of the system, regulated pumps, hydraulic balancing in the heating and cooling systems, and so on, are already in place.

If you could decide, what would you introduce, change or subsidise in Germany as a matter of priority in order to achieve significant climate-positive effects in existing buildings quickly?

I don't have to think twice about that. There are approximately 10 million gas and oil heating systems installed in Germany. A good 60 percent of these systems are 20 years old or older. They need to be renovated and replaced with climate-friendly systems. This certainly includes photovoltaic systems. To promote them more effectively, I would significantly improve the remuneration for the electricity generated and fed into the grid for system operators. For example, if you purchase electricity for your home, it costs around 400 euros/MWh, and the price is rising. If, on the other hand, you produce electricity that you do not consume yourself, you only receive a constant 60 euros/MWh for it. This would benefit owners who invest in the environment and their security of supply.