GrowSmarter

The project worked with integration of energy retrofitting into a full-scale renovation of residential buildings owned by a public housing company, Stockholmshem. The scope of the energy retrofitting was very broad with a combination of passive and active technologies. The outcome for tenants was apartments with higher standards and better indoor comfort after renovation, while the property owner benefited from lower energy and maintenance costs. Skanska AB (project development and construction group) implemented energy efficiency measures in six buildings with a total of 323 apartments in the area of Valla Torg in Stockholm. The refurbishment involved the upgrade of thermal envelope and a combination of district heating, geothermal heat pumps, exhaust air heat pumps, photovoltaic cells and heat recovery from waste water. A new smart building management systems and indoor temperature sensors were installed. Tenants were also offered to have a home energy management system installed to help monitor and optimize their use of energy and hot water. The business model for the refurbishment was to lower the energy and maintenance cost of the building. Overall, the measure lowered the total energy consumption of the buildings by up to 76% and made heating saving up to 78%. Low-energy retrofitting like the one done at Valla Torg are expected be part of an attractive market in the future due to the low energy consumption and carbon footprint of the building.