Solar power and geothermal energy used in over 9,000 SATOhomes

SATO’s new construction has been on hold due to an oversupply in the rental housing market. Instead of building new properties, we have invested in the maintenance of our existing portfolio and in improving the energy efficiency of SATOhomes. Last year’s most significant energy investments were made in capital region, where we switched to geothermal heating in five properties and installed solar power systems in 60 houses.

In recent years, SATO’s investments in locally produced, renewable energy have been significant. At present, more than 8,500 SATOhomes have their own solar power systems on the roof, and over 2,100 of SATO’s rental homes are heated with geothermal heat produced within the property’s own grounds. During 2025, the number of homes covered by renewable energy increased from around 6,000 to almost 9,200.

By using energy produced locally in our properties, we are able to reduce purchased energy and the greenhouse gas emissions generated by our business.

Locally produced solar power is used in SATO’s apartment buildings as property electricity, for example for lighting and ventilation of common areas. In 2025, no greenhouse gas emissions were generated from the property electricity used in SATOhomes, as all of our purchased electricity came from 100% wind power.

Energy efficiency improves year by year

SATO aims to increase its energy efficiency and the number of rental homes belonging to energy class A, B or C. At the end of the year under review, there were 9,303 rental homes in class A, B or C, accounting for 35% of the total of SATO rental homes. The number of homes classified A, B or C increased by 1,105 apartments over the year. Investments continue this year, too.

Water meters installed in nearly a thousand SATOhomes

Over the past year, we also installed apartment-specific water meters in 901 of SATO’s rental homes. Thanks to these apartment-specific meters, our residents can monitor their own water consumption. Real-time monitoring of water use is available alongside other services in residents’ digital OmaSATO service. According to a study by Motiva, apartment-specific water meters typically reduce water consumption by around 8% per year.

Biodiversity embedded in design guidelines

We also continued our work to promote biodiversity and prevent biodiversity loss in the built environment. We updated our property design and maintenance guidelines, continued staff training and shared best practices from several pilot properties where we tested nature-based solutions such as creating meadows and planting berry bushes on the grounds of SATOhomes. The pilots have generated good feedback from residents and will be continued in 2026, too.

Determined work for sustainability

SATO’s sustainability work is governed by our strategy, sustainability policy and Code of Ethics. Our sustainability priorities and annual measures are based on the themes of our Sustainability Programme for 2023–2026: sustainable housing (environmental sustainability), communities’ wellbeing (social sustainability) and sustainably profitable (economic and financial sustainability and governance). The policies set out in our Sustainability Programme are linked to the UN Sustainable Development Goals.

In 2025, we advanced our sustainability work in line with our targets in all areas. The realisation of the annual measures in accordance with the Sustainability Programme is part of the remuneration of SATO executives and staff as a whole.

Europe’s number one in sustainability leadership

Our sustainability work received significant recognition last year among European real estate companies. We were ranked number one in the Management component of the Global Real Estate Sustainability Benchmark (GRESB) assessment. SATO achieved the highest possible score in sustainability management among more than a thousand evaluated European real estate companies