PASSIVE HOUSE

PASSIVE HOUSE

Comparison with zero energy buildings

How does it work?

More information

What is a passive house ?

A net zero-energy building (ZEB) is a building that over a year does not use more energy than it generates. The first 1979 Zero Energy Design building used passive solar heating and cooling techniques with air-tight construction and super insulation. A few ZEB’s fail to fully exploit more affordable conservation technology and all use onsite active renewable energy technologies like photovoltaic to offset the building's primary energy consumption. Passive House and ZEB are complementary synergistic technology approaches, based on the same physics of thermal energy transfer and storage: ZEBs drive the annual energy consumption down to 0 kWh/m² from the already low PassivHaus criteria of 120 kWh/m² with help from on-site renewable energy sources. Energy Plus houses are similar to both PassivHaus and ZEB but emphasize the production of more energy per year than they consume, annual energy performance of -25 kWh/m² is an Energy Plus house.

- The term passive house  refers to a rigorous, voluntary standard for energy efficiency in a building, reducing its ecological footprint.

- The Passive house standard originated from a conversation in May 1988 between Bo Adamson of Lund University, Sweden, and Wolfgang Feist of the Institute for Housing and the Environment, Germany. Their concept was developed through a number of research projects, aided by financial assistance from the German state of Hessen.

To minimize the total primary energy consumption, the many passive and active daylighting techniques are the first daytime solution to employ. For low light level days, non-daylighted spaces, and nighttime; the use of creative-sustainable lighting design using low-energy sources such as 'standard voltage' compact fluorescent lamps and solid-state lighting with Light-emitting diode-LED lamps, organic light-emitting diodes.

Normal house VS Passive house

Performance Characteristics ;

How many ?

• Annual heat requirement ≤ 15 kWh/m2/year

(4.75 kBtu/sf/yr)

• Primary Energy ≤ 120 kWh/m2/year (38.1 kBtu/sf/yr)

• Passive houses sometimes have a dual purpose 800 to 1,500 watt heating and/or cooling element integrated with the supply air duct of the ventilation system, for use during the coldest days. It is fundamental to the design that all the heat required can be transported by the normal low air volume required for ventilation. A maximum air temperature of 50 °C (122 °F) is applied, to prevent any possible smell of scorching from dust that escapes the filters in the system.

Estimates of the number of Passivhaus buildings around the world in late 2008 ranged from 15,000 to 20,000 structures.As of August 2010, there were approximately 25,000 such certified structures of all types in Europe, while in the United States there were only 13, with a few dozens more under construction.The vast majority of passive structures have been built in German-speaking countries and Scandinavia.