To support its entry into the Australian housing sector, Ichijo Technological Homes used the concept of passive design as the foundation of its heat recovery ventilation system to achieve over eight stars in the NatHERS rating.
Energy efficient power, insulation, lighting and hot water have all become the norm in today’s environmentally sustainable housing market.
Other factors to be considered include the sustainable life-cycle assessment of material used, and ensuring that indoor environmental quality standards meet occupant comfort demands. The main aim is to minimise demand on resources and energy consumption over the lifetime of a building.
One company that has been at the forefront of the design and manufacture of energy saving domestic heating and cooling systems is Stiebel Eltron. Through its subsidiary, Stiebel Eltron Australia (SEA), the company’s products have been available in Australia since 1996.
SEA's sales manager for NSW, Jason Kerr, said that to withstand the extremes of the Australian environment, the company has had to design custom equipment including heat pumps, water filters and heaters for the local market.
When Ichijo Technological Homes entered the Australian market in 2010, it knew that top-quality, effective heat recovery ventilation systems would be required. Ichijo builds more than 10,000 homes each year in Japan, the US and now Australia.
Stiebel Eltron’s LWZ 270-plus is a central ventilation system designed to supply fresh air to medium-sized apartments and family homes with living areas of up to 290 square metres.
Using a counter-current flow, it uses thermal energy from air being extracted from a residence to heat up the incoming fresh air.
The design of the unit allows up to 90 per cent of the energy from the vented air to be recovered. The heat exchange system is equally effective in warmer climates where incoming air is cooled.
It is known as the Passive House (Passivhaus) building standard, which first originated in Germany in 1988.
The quality of the air and the effectiveness of the filtration incorporated in the ventilation system has helped Ichijo’s demonstration home in Sydney be approved by the National Asthma Council.
It has also achieved an 8.4-star rating for energy efficiency on the Nationwide House Energy Rating Scheme (NatHERS) rating scale.
NatHERS uses computer simulations to assess the potential thermal comfort of Australian homes on a scale of zero to 10 stars.
“Passively” heating the home by making efficient use of the sun, internal heat sources and heat recovery means that the home only requires minimal use of conventional heating.
“It is possible that by incorporating a range of wall insulations, along with argon-filled double glazing for windows, savings of up to 60 per cent of heating and cooling load of a traditionally constructed 5-star building can be achieved,” Kerr said.
The total energy consumption of a certified ‘passive house’ is a maximum of 120 kWh/(m²a) for heat, hot water and household electricity.
As energy savings equals emissions reductions, the ‘passive house’ goal is a sustainable alternative to conventional construction.
The money saved by purchasing smaller heating and cooling systems can be spent on improved windows, thicker insulation and a ventilation system.
A special feature on Indoor Air Quality (IAQ) appears in the February edition of Climate Control News Magazine.