Saving energy costs: What can you do as an investor in residential and office buildings? __

Saving energy costs: What can you do as an investor in residential and office buildings?
28. June 2022 6 min.

Buildings are generally known for being energy guzzlers. The reasons can be the lack of thermal insulation or outdated heating and cooling technology. In addition, residential and office buildings often still rely on fossil fuels. Appliances that consume too much energy are often found in these buildings and the high costs from the factors mentioned above burden many different parties involved in the construction of the property. This includes investors.

A large number of sustainable energy concepts are being implemented in the new construction sector but new buildings only account for three percent of the energy consumption of buildings in Germany. The much larger share must be attributed to the aforementioned existing buildings.

Due to this situation, investments cannot only be made in the construction of sustainable new buildings. Existing properties must be looked at closely and energy-efficient refurbishment considered. Although this requires investors to make financial resources available, the investment in the sustainability of a building is worthwhile in the long term.

The following examples highlight the options which investors can use to reduce energy costs of residential and/or office buildings.

Why is it important for buildings to become more sustainable?

Since 2019, the European Green Deal has tightened the previously set climate protection targets. The associated measures also include the EU taxonomy and this is linked to assessment criteria for the real estate industry.

Further measures of the EU taxonomy result from the ESG requirements. They are considered standard criteria for sustainable investments and decisions by investors, real estate owners, as well as municipalities and companies. In order to meet the ESG criteria, climate-protecting individual measures, such as the installation of photovoltaic systems or the improvement of thermal insulation, must be implemented.

Residential and office buildings that meet these criteria have a positive public image as they are considered to be as sustainable and energy-efficient as possible. Investors benefit from the sustainability and low operating costs of the buildings in which they have invested.

Compliance with ESG criteria is becoming increasingly important, as the construction industry accounts for a high proportion of global energy consumption and is responsible for a large proportion of energy and process related CO2 emissions. For all those involved in a construction project, such as architects, planners, and investors, energy-saving and sustainable measures for real estate are becoming increasingly important.

How can energy costs in residential and office buildings be reduced in the long term?

In order to reduce the costs for energy, there are a wide variety of concepts and construction methods. The following examples in the residential and office sector present some of these ideas, many of which have already been implemented and built.

All properties have one thing in common: they rely on a mix of different energy sources to cover the energy needs of a building. At the same time, this variety of sources also means that the operating costs of the property are significantly reduced in the long term.

Residential buildings: The aquatherm project HUF City Living Montabaur

The HUF City Living complex in Montabaur not only contains 44 residential units, unusual architecture and state-of-the-art technology also come together here. The exclusive residential project was built in accordance with the KfW 55 energy standard.

In HUF City Living, aquatherm black was installed within the ceiling. This surface heating and cooling system from aquatherm made an important contribution to meeting this standard and was a significant component of the project.

In this environmentally friendly energy concept, heating storage meets a power roof

Ice energy storage, photovoltaics, hot water collectors, and heat pumps were combined as energy sources in the sophisticated energy concept for these residential buildings. aquatherm black formed part of this concept asthe system is self-sufficient and invisibly installed within the ceiling or floor in all flats. The central element is the ice energy storage tank asthis feeds several heat pumps in the individual technical rooms of the buildings and is coupled with many solar double modules on the shedroofs of the houses.

This allows the ice store to bundle the energy from the ambient air, solar radiation, and the ground. Another part of the heating energy is covered by crystallisation energy and three buffer storage tanks, which generate the reserve energy without clocking the heat pumps, are used per house.

Further information about aquatherm black

The surface heating and cooling system is manufactured in a compact register construction and has future-proof technologies. aquatherm black can be installed in the wall, in the ceiling and in the floor. The surface temperature of the elements can be adjusted a few degrees above or below the desired room temperature. The radiant energy thus generates pleasant heat or cooling without disturbing draughts.

For more information about the aquatherm surface heating and cooling system, please visit the following product page:



Three sustainable energy sources make residential projects low-maintenance and emission-free

In order to be able to operate the heat pumps, photovoltaic systems were installed on the roofs. Significant savings can be made with the energy generated annually. Air absorbers can use the waste heat from the solar modules and cool them at the same time. Instead of using absorber pipes, aquatherm black is used here. In addition, the power roof has high surface efficiency.

The aforementioned double modules not only generate PV electricity, but also solar thermal heat. This heat is fed into the ice storage and the electricity generated is used to operate in the public areas such as building services and lighting. The flats can be cooled almost free of charge in summer with the surface heating and cooling system.

The combination of the three energy sources mentioned above is a resource-saving basis for the air-conditioning of the flats, as well as being low-maintenance and emission-free. Investors who rely on ice storage, heat pumps, and solar twin modules can save a lot of money in the long term on their residential buildings.

BVF Award

The specialist planners Etgenium, fabricator Jupp Willing Heizungsbau and aquatherm accepted the BVF Award 2016 for the building project. With this award, the Bundesverband Flächenheizungen und Flächenkühlungen e.V. (BVF) (Federal Association for Surface Heating and Cooling) recognises the professional interaction between building owners, specialist planners and the system manufacturer.


Measures and ways to save energy costs in office buildings

The climate balance of office buildings is inferior to that of residential buildings. In addition, retail and hotel properties are also counted as commercial properties and in Germany these account for about twelve percent of the total building stock. On paper, this figure seems small. But this percentage consumes 40% of the total energy of all buildings in Germany.

There are now ways and means to measure the sustainability of buildings - such as the Sustainable Building Rating System. In addition, architects and planners are working with investors to construct office buildings that are (more) sustainable and climate neutral.

Assessment system for sustainable building (BNB)

This assessment system is regarded as a holistic assessment methodology for (office) buildings and their immediate surroundings. The BNB shows how a property affects its surroundings in terms of ecological, economic and socio-cultural quality.


In the case of office buildings, the Sustainable Building Rating System takes into account criteria such as the impact on the environment, user-friendliness, comfort, health, use of resources, space efficiency, adaptability to use, deconstruction, separation and recycling possibilities of materials used.


Possibilities for sustainable and climate-neutral design of office buildings

It’s not just new buildings that can be sustainable and climate neutral. Existing buildings can also be designed accordingly. By refurbishing existing buildings, construction waste that would otherwise be generated by demolition and the emissions associated with new construction, can be avoided from the outset. Old buildings often lack thermal insulation but when this is added, energy efficiency can be significantly improved.

The use of photovoltaic systems is not only worthwhile for residential complexes, but should also be a must for office buildings. If architects opt for modular construction and use wood as the main material, an office building can become CO2-neutral and fully recyclable.

Energy refurbishment of existing buildings

Far too few existing properties are refurbished in UK. The problem is that there aren‘t any concrete targets for refurbishment. Moreover, energy-efficient refurbishment means a considerable investment for the property owner.


However, investments in the sustainability of buildings can pay off in the long term for building owners, property operators and investors. Photovoltaic systems and geothermal systems recoup their costs after a few years. With these investments, the operating costs of an office building can be permanently reduced. This development should not be forgotten in the overall economic result.


How dekoGraphics meets its primary energy needs efficiently, environmentally friendly, and economically

The new building, which was built for the market leader in thermal transfer printing in St. Leon-Rot near Heidelberg, contains a heat pump system with 45 kW heating capacity in combination with a 70,000 litre ice energy storage tank. In addition, there is a power roof including a photovoltaic arrangement and a charger system.

An important part of the overall set-up is aquatherm black, the harp-shaped pipe system made of the corrosion and UV-resistant plastic polypropylene. This was mounted as a solar air absorber on the flat roof of the building and filled with a water-glycol mixture. The system extracts heat from the ambient air and solar radiation, which is used as a direct source for the heat pump as well as for regenerating the ice storage tank.

aquatherm black contributes significantly to the cooling of the photovoltaic system thus increasing the efficiency of electricity generation. The power roof, with its ice storage and heat pumps, is currently one of the most efficient, environmentally friendly and economical heating systems in Germany.

Electrical energy can be used to drive the heat pump and other electrical consumers in the building. Thermal energy is used directly via the heat pump and stored temporarily in the ice store. All this occurs without harming the environment and allows dekoGraphics to make use of its properties and contribute sustainably to the reduction of CO2 emissions.


Conclusion: In the long term, the environment and investors benefit:

If the measures and energy concepts presented in this paper are implemented, residential and office buildings can not only cover their own electricity needs, but also feed surplus electricity into the existing grid. Sustainable and energy-efficient buildings reduce their own operating costs, fulfil the ESG criteria set by the European Union, and make an important contribution to climate and environmental protection.

Would you like to learn more about how aquatherm lives sustainability? Or do you want to know how you can achieve your goals in this area with our piping systems? Then we recommend you to take a look at our sustainability page.

Achieving sustainability goals with aquatherm piping systems