At the moment, more than a half of the City of Helsinki’s carbon dioxide emissions are caused by heating buildings. Very strict and binding energy-efficiency requirements have been established for the City’s own building stock, both for new construction and renovation construction.

The objective of Heka's HELENA project (Heka’s ELENA energy efficiency activities HELENA) is to achieve up to 40% savings in energy consumption of its deep renovation projects commissioning multi-objective optimization for each Heka site going through extensive renovations over the next three years. The optimization will be done for about 170 residential buildings. 

The energy consumption of buildings is built on several variables and there are up to thousands of combinations. The conventional examination of few ways to improve the energy efficiency may not find the best and most cost-effective solutions. Multi-objective optimization compares up to millions of site-specific solutions simultaneously when we want to understand things as a whole and the impact of different variables on each other. The most appropriate optimization package will be selected for every building in terms of life cycle cost and energy efficiency improvement.  

Multi-goal optimisation can help significantly improve the energy-efficiency of residential buildings which will result in a combination of building envelope renovation, heat recovery systems and the installation of building integrated PVs of optimal energy efficiency measures and building-integrated renewable energy sources. The data collected through this project can also be utilised to identify the most profitable ways  

in energy-efficient renovation construction in the private sector in both Finland and Europe.  

The HELENA project is mainly implemented with ELENA funding, a support scheme managed by the European Investment Bank and funded by the EU's Horizon 2020 program. 

  • Duration of the project: 1.10.2020-30.9.2023. 
  • Project budget: 2 034 000 euroa. 

More information: Project manager Jenni Korsrå, jenni.korsra(at) 

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