The dena has presented a detailed analysis of the building transition in Germany with its Building Report 2026 Update September. The results indicate that development varies depending on the market segment. Particularly in the heating sector, there is a significant increase in demand for heat pumps, while gas heating is losing relevance in new builds. In contrast, the expansion of building-integrated solar systems has shown a noticeable decline after adjustments to the framework conditions in the Solar Peak Act and due to uncertainties in funding.
Corinna Enders, Chairwoman of the dena management board, noted that the current figures demonstrate the rapid progress and the standard character of the shift to modern, climate-friendly heating systems in new builds. She emphasised, however, that the pace of transformation in existing buildings must be accelerated. With the Building Modernisation Act and the new BEG funding conditions, the necessary clarity has now been established. The task now is to communicate the regulations clearly and enable homeowners to plan their investments with certainty. She highlighted the necessity of long-term reliable framework conditions as crucial.
Dominance of heat pumps in new builds and need for action in existing stock
The data included in the update clarifies a distinct shift in heat supply in new builds towards renewable energies, electricity, and district heating. These three areas already reached a share of over 89 percent in completed residential buildings in 2025, compared to approximately 85 percent in 2024. Heat pumps were the decisive factor here last year, with a share of just under 74 percent. Gas heating, however, reached a historic low of around eleven percent.
In the existing building stock, the change is progressing more slowly. In 2025, gas heating continued to dominate the housing stock, but showed a slight turnaround. After continuous increases in previous years, its share registered a first slight decrease in 2023 and fell from 56.2 to 56.1 percent in 2025. The share of heat pumps in existing buildings rose by 5 percent in 2025 compared to the previous year. Current sales figures for heating systems confirm this trend: In the first half of 2026, 194,500 heat pumps were sold, representing an increase of 40 percent compared to the same period last year. Sales of gas heating units stood at 134,000 devices, a slight increase of one percent compared to the previous year's figure. Already in 2025, with approximately 299,000 units sold, the heat pump was the best-selling heating system in Germany, increasing its market share from 48 percent (2025) to 55 percent (1st half of 2026). Ms Enders expressed hope that this trend would soon also be observed in building efficiency, insulation, and window replacement.
Restrained solar expansion and growing battery storage market
The update report paints a mixed picture for building-integrated solar expansion. In the first half of 2026, the addition of solar systems decreased by 17 percent, although it remains at a high level. The mark of approximately 80 gigawatts of building-integrated solar has been reached overall. The development of battery storage, however, is significantly more positive. In July, storage capacities of 30 gigawatt-hours (GWh) and approximately 2.6 million devices were reached. Currently, around 47,400 new storage units are added monthly. Particularly strong growth is currently observed in the segment of large-scale battery storage systems. Nevertheless, the majority of installed storage capacity, around 24 GWh, is accounted for by home storage in residential buildings. The storage market has been growing faster than the solar market for over a year, underlining the increasing importance of flexibility and self-consumption for the energy transition in the building sector.
