Everyone talks about the winter when the heating in offices and homes should be turned down to save gas and money.

But the costs are rising, and power consumption in Frankfurt and Rhine-Main traditionally skyrockets with the summer temperatures.

According to the energy supplier Mainova, especially in the city with its office towers, data centers and airport, the hot days are those when a particularly large amount of electricity is consumed.

In view of the increased prices for the building operators, this will be expensive, and so it can now be a bit warmer on hot days like today.

This applies, for example, to the shopping centers that the company ECE operates in Frankfurt and the region.

In My Zeil, Skyline Plaza or in the Main-Taunus-Zentrum, the temperatures have so far been 22 degrees in both summer and winter, only on particularly hot days could it be warmer inside.

"On the one hand, to save energy, on the other hand, so that visitors are not exposed to large temperature differences," said an ECE spokesman.

Now the drop in temperature is getting smaller: "In addition, we are now reducing energy consumption through less cooling than usual."

At the Chamber of Industry and Commerce, which is located in the historic stock exchange building in Frankfurt, 24 degrees is the standard temperature for the summer, but only the rooms in which someone works or that are used for events are cooled, emphasizes a spokeswoman.

In addition, the systems for ventilation and cooling are currently being renewed, including a central distribution of the cooling water and modern control technology to optimize consumption.

Wind, efficient technology and less space

The 259 meter high Commerzbank tower should not be a place to escape from sweating in the heat: Instead of eternal spring temperatures, the building is always kept only six degrees colder than the outside temperature, a spokeswoman reported.

This moderate cooling is provided by ceilings through which cold water is pumped, and the windows are left open at night to freshen up the offices with the help of the wind.

The competitors from Deutsche Bank rely on wind, efficient technologies and less office space.

Ten years ago, when the twin towers were renovated, their energy consumption was greatly reduced.

Now the area that Germany's largest financial institution has available for its employees is being reduced.

"Due to changing requirements, such as mobile working, we have already adjusted our real estate portfolio in recent months," says a spokeswoman.

These efforts are unlikely to change the general trend that summer costs more and more electricity: Over the past ten years, more and more air conditioning systems have been installed in residential buildings, and nationwide the energy consumption for cooling buildings has been increasing significantly for almost ten years and is now at 11 terawatt hours.

However, ten times as much energy is used for heating.