Green Group Expands Certifications


An apartment building in Europe has become the first to be certified under a new classification of energy-efficiency that has a rigorous performance-based standard.

The Passive House Institute (PHI) certified a 16-unit apartment complex in Innsbruck, Austria, as Passive House Plus. The new category has a lower limit for primary source energy and requires buildings to generate renewable energy in order to achieve the certification.

“The question whether it is possible to supply a residential building completely through renewables, throughout the entire year, has clearly been answered by ‘Neue Heimat Tirol’: yes, it works," said Dr. Wolfgang Feist, director of PHI, in an Aug. 4 statement about the apartment building certification.

Multi-Family Plus

The complex in Innsbruck consists of two new buildings that are connected through an underground garage. One of the buildings, which contains 10 apartments, was certified under the Passive House Classic standard.

But the 16-unit building uses a ground water heat pump, a solar thermal system and a photovoltaic installation. Those upgrades enabled it to fall into the “Plus” category, PHI said.

PHI introduced the new classes in March. The Darmstadt, Germany-based organization added the Passive House Plus as well as the Passive House Premium standards to focus on not just how much energy a home consumes, but also how much it generates, the group said.

Three Levels of PERs

For all PHI classes—including the original Passive House Classic—the heating demand cannot exceed 15 kWh/(m²a). But instead of focusing on just demand, the classes now categorize a building on Primary Energy Renewable (PER).

For the Classic category, a building cannot consume more than 60 kWh/(m²a) of renewable energy. A Plus cannot consume more than 45 kWh/(m²a) of PERs and the Premium—at the top of the line—can consume only 30 kWh/(m²a), the group said.

But Plus and Premium certified buildings also must generate PERs. For Plus, the PHI standard is at least 60 kWh/(m²a) of energy in relation to the area covered by the building, while Premium standards require at least 120 kWh/(m²a) of energy being generated by the building, the group has said.

In both cases, the sun and wind provide the majority of the renewable energy. However, the buildings also must have a way to store and transfer those electricity resources from times when the energy has a surplus to times when they are more minimal, PHI says.

European Standards

“The energy supply structure worldwide is transitioning from fossil fuels to renewable sources at an encouragingly rapid pace,” said Jessica Grove-Smith, a senior scientist at PHI, in an Aug. 14 article in Architectural Record.

Grove-Smith told AR that not only do the new standards take into account the storage and transmission losses to balance energy demand versus supply, they also intend to meet the European Union’s standards for Nearly Zero Energy Building (NZEB). By 2020, all new buildings must meet those standards.

The apartment complex was not the first building to achieve the Plus certification. A single-family home in Ötigheim, Germany, earned that status in July, PHI said in a statement at that time.

PHI has not certified any buildings under its new Premium class since developing the standards, according to the group’s website.


Tagged categories: Building Envelope; Energy codes; Energy efficiency; Europe; Green building; Green design; Net Zero Energy ; Passive house; Solar energy

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