Well, it could theoretically be heated by a hairdryer, at least. While that attention-grabbing headline needn't be taken too literally (it appears to refer to the equivalent energy required for heating), in Park Passive House, NK Architects has produced an energy-efficient and attractive modern family home. It also happens to be Seattle's first certified Passive House, and so will hopefully provide inspiration for more similarly efficient homes to be built in its wake.
Park Passive House was completed in 2013 and sits on an urban infill lot – or a lot that isn't typically considered suitable for building upon, usually due to it being located in an underdeveloped or unattractive area – that measures just 185 sq m (2,000 sq ft).
The three-story house has a total floor space of 251 sq m (2,710 sq ft), which includes four bedrooms, three bathrooms, a large double-vaulted kitchen, a children's play area, and living and dining areas. In a small but nice touch that reflects the environmental focus of the design, a salvaged tree was used for the staircase, wall paneling, and bathroom counter.
NK Architects reports that Park Passive House uses up to 80 percent less overall energy, when compared to an average home built in accordance with today's building code standards. While we've no hard figures concerning the actual energy used while all the amenities are running, Passive House certification is a particularly exacting set of standards to meet for aspiring energy-efficient builds, so we should be able to take the firm at its word.
Park Passive House has an airtight (or very near-airtight) envelope that helps it retain an average indoor temperature of 21ºC (70ºF), which is adjusted with passive ventilation by simply opening and closing windows and doors in summer.
When colder weather hits, the house also sports a heat recovery ventilator, while generous and efficient windows ensure that plenty of natural daylight permeates the interior. In addition, Park Passive House also has a heat pump, lots of insulation, and wiring ready for the installation of solar power (though no solar panels have been installed as of yet).
Source: NK Architects via Arch Daily
As for performance, I have data that show passive house does deliver 80% energy reduction. We compared our energy use for the first year of living in our passive house with the energy bills provided to us by previous owner of the house. It did show 80% reduction. You can see the numbers and the energy details on my blog: http://midorihaus.blogspot.com
And, it is a modest sized house at 1569 square feet or 146 square meters.