Decarbonising residential buildings: ista acquires Homenergy

• ista expands its energy solutions business for residential buildings to include heat pumps and photovoltaics
• Opening up new future markets
• Bringing together two companies and their respective strengths

Essen, 1 October 2026 — Energy and real-estate service provider ista is acquiring Homenergy GmbH, an established provider of planning and installation services for heat pumps, photovoltaic systems and complementary energy solutions. With the acquisition, ista expands its range of integrated energy solutions for the decarbonisation of buildings.

In the past four years alone, Homenergy has sold and installed around 4,500 heat pump and photovoltaic systems. Its offering also includes battery storage, wallboxes, home energy management systems as well as service and maintenance.

"With Homenergy, we gain an experienced team and a powerful platform that enables the decarbonisation of buildings. As ista, we want to use this expertise for all our customers to make decarbonisation as simple as possible," says ista CEO Hagen Lessing. "But the energy transition in the building sector takes place not only in multi-family buildings, but equally in millions of single- and two-family homes. With Homenergy, we plan to open up an important future market and expand our offering with solutions for climate-friendly energy supply. Overall, we are bringing together two companies with their respective strengths."

Energy solutions from a single source

With the acquisition of Homenergy, ista consistently continues its strategic course of becoming a full-service provider of integrated energy solutions for buildings. "Our customers want solutions that combine energy efficiency, climate protection and economic viability. Together with Homenergy, we will be able to support them even more comprehensively in transforming their properties," says Lessing.

Supporting customers in transforming their energy supply

Homenergy has a fully digitalised customer journey and covers key parts of service delivery — from sales and technical planning through project management and installation to service.

"Together with ista, we can take Homenergy to the next stage of development," says Hannes Münzinger, Managing Director of Homenergy. "We combine our experience in heat pumps, photovoltaics and digital installation processes with ista's reach, customer relationships and infrastructure. This gives us the opportunity to help significantly more customers transform their energy supply."

Strong growth in heat pumps

The German heating market faces a long-term transformation. In the first half of 2026, the German heating industry sold significantly more units than in the same period of the previous year, above all heat pumps. According to the Federal Association of the German Heating Industry (BDH), around 352,000 heat generators were sold from January to June, 19 percent more than in the first half of 2025. Heat pumps accounted for more than half of all installations (194,500).

About Homenergy

Founded in 2022, Homenergy is a provider of energy solutions for residential buildings. The company plans and installs heat pumps and photovoltaic systems in particular, and offers complementary solutions such as battery storage, wallboxes, home energy management as well as maintenance and service. Homenergy employs around 65 people and has locations in Munich and Essen.

About ista

We give houses a future — with products and services that help reduce the CO₂ emissions of buildings. We manage data and processes that make energy consumption transparent and properties safer. Our products and services are digital at their core. With more than 50 million radio devices in use worldwide, over 6,800 employees in 20 countries and more than 470,000 customers, ista's products and services are used in over 14 million apartments and commercial properties. In 2025, the extended ista Group generated revenue of €1,279 million. More information at www.ista.com.