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Using subsi­dies to heat more effi­ciently

We have set a course for the energy revo­lu­tion. Heating plays a very impor­tant role here. With state-of-the-art heat pumps, gas condensing boilers, etc., effi­cient system compo­nents from ebm-papst, and attrac­tive state funding, envi­ron­men­tally friendly construc­tion and reno­va­tion are now moving full steam ahead.

The EU’s main objec­tive: climate neutrality by 2050. The driving force behind this is renew­able energy. And this is exactly where the big poten­tial for heating is: around 40 % of total final energy in Germany is consumed in build­ings; around 85 % of the energy is used for building heating and hot drinking water supply.

Millions of heating systems in Germany are more than 15 years old and their energy effi­ciency is far lower than the latest tech­nology. But which systems should house builders or buyers turn to? We show which heating concepts are partic­u­larly envi­ron­men­tally friendly, how system compo­nents from ebm-papst support climate protec­tion, and which funding program is worth­while for which solu­tion.

Effi­cient energy from the envi­ron­ment

Heat pumps are becoming increas­ingly popular for sustain­able heat gener­a­tion, as they mainly obtain their energy from their envi­ron­ment, i.e. from water, air, or earth. Ideally, power for oper­a­tion can also be obtained from renew­able ener­gies using photo­voltaic systems. In the future, this will also make heat pumps inde­pen­dent of increasing elec­tricity prices and will cut oper­ating costs. During oper­a­tion, heat pumps absolutely have to be quiet, regard­less of whether they are installed indoors or outdoors.

The new AxiEco series is there­fore a perfect compo­nent for modern heat pumps, as the axial fans are well suited for appli­ca­tions in noise-sensi­tive areas due to their low noise emis­sions. They also work with optimum effi­ciency. The extra advan­tage is that there are many ways of using predic­tive main­te­nance for the fans thanks to Green­In­tel­li­gence.

The new AxiEco Perform EC axial fan from the AxiEco series in the air-to-water heat pump appli­ca­tion example. It is well suited for appli­ca­tions in noise-sensi­tive areas due to its optimal flow and the resulting low noise emis­sion. (Photo: ebm-papst)

Bridging the gap with gas condensing tech­nology

In order to generate heat, modern gas condensing boilers not only use the gas itself, but also the latent heat of the water vapor contained in the exhaust gas due to the combus­tion process. This increases effi­ciency and also decreases the demand for fuel. This is currently the most impor­tant bridging tech­nology in the energy revo­lu­tion – simply by replacing old heating systems with gas condensing tech­nology and achieving the asso­ci­ated CO2 reduc­tion. It can also be easily combined with other heating concepts, for example with solar heating or a pellet stove. That makes it “renew­able ready” – which means that it can be expanded with renew­able energy sources later.

The CleanEco pneu­matic combus­tion control system (top) and the Clean­Vario elec­tronic combus­tion control system (bottom) offer a perfectly coor­di­nated complete system consisting of boiler control unit (BCU), gas valve, venturi and gas blower. (Photo: ebm-papst)

Modern condensing boilers are controlled elec­tron­i­cally and adapt the heating output very flex­ibly to the required heating load. The ebm-papst CleanEco (pneu­matic) as well as Clean­Vario (elec­tronic) combus­tion controls provide a perfectly coor­di­nated gas/air ratio control system including combus­tion control. This means that the optimum, stable mixture of oxygen and fuel is always produced. Modu­la­tion levels of 1:10 are now possible, which contributes to increasing effi­ciency and ensures very envi­ron­men­tally friendly oper­a­tion.

Whether by control­ling the gas valve with the aid of a vacuum (CleanEco, see top illus­tra­tion) or with the aid of elec­tronic control of the gas valve (Clean­Vario, see this illus­tra­tion), the optimum, stable mixture of oxygen and fuel is always created. (Photo: ebm-papst)

Hybrid systems: The best of both worlds

Hybrid systems consisting of a gas condensing unit and a heat pump are partic­u­larly useful if the gas power is required in booster mode (water heating) or at very low outside temper­a­tures. The advan­tage to you is that the heat pump is respon­sible for the heating base load; if the outdoor temper­a­tures drop signif­i­cantly into the sub-zero range, the gas condensing boiler works as a booster to provide consis­tent heat.

In order to do without fossil fuels for as long as possible, the oper­a­tors can indi­vid­u­ally control the point at which gas condensing tech­nology takes over them­selves and thus choose the cheapest oper­ating mode – depending on the elec­tricity and gas prices. This makes the hybrid system a future-proof solu­tion, as it works inde­pen­dently of indi­vidual energy sources.

A higher-level control system provides the intel­li­gence for consis­tently cozy heat – the 900H Series Control Plat­form from ebm-papst, which controls the output of the gas condensing unit and the heat pump in a targeted manner, depending on the situ­a­tion, and coor­di­nates the connec­tion or sole oper­a­tion of the condensing boiler during peaks. Here too, Green­In­tel­li­gence plays a role by ensuring predic­tive main­te­nance of the hybrid system.

The higher-level control system, the 900H Series Control Plat­form from ebm-papst, regu­lates the hybrid system’s output in a targeted manner depending on the situ­a­tion and coor­di­nates the addi­tional igni­tion of the condensing boiler when temper­a­tures are signif­i­cantly below zero. (Photo: ebm-papst)

Don’t forget about funding

It’s worth taking a look at the funding oppor­tu­ni­ties before building a new building or refur­bishing one: Germany has around six billion euros of funding avail­able for 2021. This is avail­able for both the construc­tion or the initial purchase of resi­den­tial build­ings as a KfW Effi­ciency House (building that is promoted by the KfW promo­tional bank) and for indi­vidual measures for existing build­ings (BAFA – German Federal Office for Economic Affairs and Export Control), as shown by the Feder­a­tion of German Heating Industry. This includes heat pumps, “renew­able ready” gas condensing tech­nology, and hybrid systems.


KfW program – energy-effi­cient construc­tion

Would you like to build or purchase a KfW Effi­ciency House? Depending on the level of the Effi­ciency House (the lower the level, the more effi­cient the house), the building work or purchase is supported in the form of a repay­ment bonus. A maximum of 120,000 euros per resi­den­tial unit is avail­able.
Require­ments Repay­ment bonus
KfW Effi­ciency House 55 15 %
KfW Effi­ciency House 40 20 %
KfW Effi­ciency House 40 Plus 25 %

KfW program – energy-effi­cient reno­va­tion

Would you like to opti­mize an existing heating system which is older than two years and is in a building where the building appli­ca­tion was created before December 1, 2002? This funding program from the KfW banking group promotes reno­va­tions with these kinds of indi­vidual measures and reno­va­tions to make the prop­erty a KfW Effi­ciency House with a repay­ment bonus or invest­ment grant. The basis for this is 100 % of the invest­ment costs eligible for funding. The maximum for each resi­den­tial unit is 120,000 euros for a reno­va­tion to make the prop­erty a KfW Effi­ciency House, and 50,000 euros for indi­vidual measures – up to 40 %.
Require­ments Repay­ment bonus Invest­ment grant
Indi­vidual measures 20 %
KfW Effi­ciency House 115 25 % 25% (max. 30,000 per resi­den­tial unit)
KfW Effi­ciency House Monu­ment 25 % 25% (max. 30,000 per resi­den­tial unit)
KfW Effi­ciency House 100 27,5 % 27.5 % (max. 33,000 per resi­den­tial unit)
KfW Effi­ciency House 85 30 % 30 % (max. 36,000 per resi­den­tial unit)
KfW Effi­ciency House 70 35 % 35 % (max. 42,000 per resi­den­tial unit)
KfW Effi­ciency House 55 40 % 40 % (max. 48,000 per resi­den­tial unit)

BEG EM – German federal funding for effi­cient build­ings – indi­vidual measures

Would you like to imple­ment indi­vidual measures in an existing building? The German Federal Office for Economic Affairs and Export Control (BAFA) will support your project in the form of non-repayable subsi­dies propor­tionate to the costs eligible for funding. This also includes the above-mentioned heat gener­a­tion systems such as gas condensing boilers, which are “renew­able ready”, gas hybrid systems, and heat pumps. The maximum for resi­den­tial build­ings is 60,000 euros per resi­den­tial unit. Heat pumps receive the highest funding rate of 35 % to 45 %. Tech­nical plan­ning and building support can also be supported at 50 %. 

Indi­vidual measure Funding rate Funding rate with replace­ment of oil heating Tech­nical plan­ning and building support
“Renew­able ready” gas condensing boiler 20 % 20 % 50 %
Gas hybrid system 30 % 40 % 50 %
Heat pump 35 % 45 % 50 %


You can find more detailed infor­ma­tion on the funding programs in the brochure from the Feder­a­tion of German Heating Industry.

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