An office building in Norway has been renovated to produce more energy that it consumes. Powerhouse Kjørbo is located near Oslo, and according to Powerhouse, it is Norway’s first energy-positive building and the first in the world to be renovated into an energy-positive structure.

Powerhouse is a consortium of firms aiming to develop energy-positive buildings. It comprises architecture firm Snøhetta, construction company Skanska, environmental organization ZERO, aluminum supplier Hydro and property management firm Entra Eiendom.

"As far as we know, this is the first building in the world that has been renovated into an energy-positive structure," says Ståle Rød, chairman of the Powerhouse consortium and CEO of Skanska Norway. "It is the unique collaboration we have had from the very start that has made this possible."

By Powerhouse's standards, an energy-positive building is "a building which generates more clean and renewable energy in its operational phase than what was used for the production of building materials, its construction, operation and disposal."

Powerhouse Kjørbo is actually two 2,600 square meter (27,986 sq ft) buildings on the Sandvika seafront in Bærum municipality. Their energy consumption prior to renovation was 650,000 kWh every year. Following the renovation, the energy requirements of the buildings are expected to be reduced to around 100,000 kWh per year in total.

Energy is generated by solar panels. It is expected that the solar array will produce over 200,000 kWh annually, with any excess energy being supplied to the power grid. Heat loss, meanwhile, is minimized by using tight-fitting walls, ceilings and windows, as well as insulation. Exterior sun shading and exposed concrete decks are two means of reducing temperature in the summer.

"Powerhouse Kjørbo illustrates that it is possible to construct a building that is both environmentally correct and profitable, and this makes us tremendously proud," says chief executive officer Klaus-Anders Nysteen of Entra Eiendom, which owns the building.

Source: Powerhouse