Passivistas: Transforming a 1960's residential building in Papagos, Greece

The House Project demonstrates that even in economically difficult times retrofitting existing residential buildings so that they generate more energy than they consume is both financially and technically feasible.

Bringing together a team of experts and finding support from private sector partners as well as via crowdfunding, renovation works were carried out in 2015 and 2016 using materials and technologies available on the market. The cost for transforming the 125m2 two-level structure into a positive energy building (PEB) will be amortised in under seven years by energy savings.

The Passivistas team has made a great contribution to raising awareness and building capacities for PEBs with over 1,000 visitors taking part in open house events and seminars. Whilst the project already has great replication potential in Greece and beyond, scaling up the energy efficient renovation of residential buildings could be catalysed further by tailored financial solutions, more ambitious regulations, and incentive schemes.

Read the whole study here.

Powerhouse Kjørbo: Taking a Life-Cycle Approach to Positive Energy Buildings

Powerhouse Kjørbo (Norway) is a renovation project of two former office buildings that were originally constructed in 1979. It was the first time that buildings were renovated to a positive energy building standard.

An important first step towards reaching this target was to reuse and select environmental friendly construction materials. In addition, a ground-source heat pump system was installed in combination with an efficient ventilation system.

Special attention was paid to visual comfort by maximising the use of natural daylight. The heavy concrete structure optimises thermal comfort as the thermal mass tones down temperature fluctuations. Powerhouse Kjørbo received great national and international attention from authorities, politicians and professionals.

The project demonstrates that the positive energy building concept is feasible even in colder climates both in a commercial and environmental context.

Read the whole study here.