Solar Wonders, ©2007 Florida Solar Energy Center 1 A Renewable Energy House in Australia A case study of a successful renewable energy project

Solar Wonders, ©2007 Florida Solar Energy Center 2 Summary The Arrillhjere Demonstration House, part of the Gloria Lee Environmental Learning Centre, was built in the harsh, arid climate zone of central Australia using ecologically-sustainable design principles. It has its own water- collection and energy systems based on renewable energy sources.

Solar Wonders, ©2007 Florida Solar Energy Center 3 Background Because of the home’s harsh environment, it presented a design challenge to achieve comfortable living conditions during both the hot summers and the cold winter nights.

Solar Wonders, ©2007 Florida Solar Energy Center 4 The home features: Minimal energy use in construction Energy costs below $197 U.S. per year Large shaded outdoor spaces PV panels and solar water heater

Solar Wonders, ©2007 Florida Solar Energy Center 5 Electricity is provided by a 720-W solar system made up of six 120-W monocrystalline photovoltaic panels. The system is connected to a bank of lead acid batteries. The thermosyphon solar water heating system is mounted in front of the PV system.

Solar Wonders, ©2007 Florida Solar Energy Center 6 Weather conditions In summer, the mean daily maximum temperature is 95.9 o F, with highs reaching 113 o F. The winter mean temperature is 38.5 o F, with temperatures often dropping much lower. The average annual median rainfall is 257 mm.

Solar Wonders, ©2007 Florida Solar Energy Center 7 Conventional indigenous housing in the area Local homes in the region typically have diesel generators, septic tanks and minimal shading. Arrilhjere is a private house, built to show what can be achieved with sustainable technologies.

Solar Wonders, ©2007 Florida Solar Energy Center 8 The demonstration house This home has a self-supporting, steel-framed umbrella roof which creates shaded outdoor spaces and provides shading for the external walls. The enclosed floor area is 135 m 2.

Solar Wonders, ©2007 Florida Solar Energy Center 9 The large umbrella roof creates comfortable, shaded outdoor living spaces.

Solar Wonders, ©2007 Florida Solar Energy Center 10 Building methods Earth-building methods were adopted to achieve a culturally- appropriate, environmentally- responsible living environment. The walls are constructed from hand- made earth bricks, with a sand-filled cavity to provide thermal mass and lower the embodied energy compared to conventional construction.

Solar Wonders, ©2007 Florida Solar Energy Center 11 The walls are waterproofed to last longer and have a more efficient life-cycle cost. Earth-based paints were used to lighten the internal walls. The house is linear in design with an east- west axis to minimize wall exposure to the summer sun and to improve cross- ventilation.

Solar Wonders, ©2007 Florida Solar Energy Center 12 Ventilation Five stationary ridge vents connected by a flexible duct to an adjustable ceiling fan help provide ventilation. Ceiling fans on timer controls help eliminate the need for air conditioning and improve health conditions.

Solar Wonders, ©2007 Florida Solar Energy Center 13 Rainwater Rainwater is stored in two large steel tanks. When water is needed, a circulating pump sends it to a tank and then it is drawn by gravity into the house. Water-saving devices are attached to the shower and sinks, and a composting toilet further reduces water demand. Used household water is recycled to the fruit tree orchard.

Solar Wonders, ©2007 Florida Solar Energy Center 14 PV system provides electricity The six north-facing panels are mounted on the roof and connected to 24 batteries, managed by a solar regulator and inverter. No back-up generator is used. Energy-efficient appliances are used in the house.

Solar Wonders, ©2007 Florida Solar Energy Center 15 The solar water heating system The solar water heating system operates in a closed circuit with a heat transfer fluid to prevent freezing.

Solar Wonders, ©2007 Florida Solar Energy Center 16 Performance The PV system typically produces 2.8 to 3.8 kWh/day. Battery capacity is 5 kWh. It provides power for lights, ceiling fans, freezer, washing machine, water pump, iron, toaster, microwave oven, computer, television set, video recorder and a radio.

Solar Wonders, ©2007 Florida Solar Energy Center 17 The rainwater system provides enough water for two to three people. The only non-renewable fuel used is liquid propane gas, used for cooking and to operate the refrigerator.

Solar Wonders, ©2007 Florida Solar Energy Center 18 Economics The cost of all materials, equipment, appliances, management and labor for the house was about $93,200 U.S. This included about $26,300 for the extra costs of the sustainable technology components and renewable energy systems, including: $10,500 for the PV system. $1,200 for the solar water heater

Solar Wonders, ©2007 Florida Solar Energy Center 19 Savings The only energy costs in this home are for the LPG – under $200 per year. It is estimated that the minimum energy costs for hot water, cooking and electricity in a non-solar house would be $650 to $900 annually.

Solar Wonders, ©2007 Florida Solar Energy Center 20 Further benefits Without the passive solar design aspects, space heating and cooling costs would increase significantly. Further, living conditions in the home have been greatly improved as compared to typical indigenous housing in the region.

Solar Wonders, ©2007 Florida Solar Energy Center 21 For more information... To learn more about this project, contact: Gloria Lee Environmental Learning Centre P.O. Box 7951 Alice Springs Northern Territory 0871 Australia

Solar Wonders, ©2007 Florida Solar Energy Center 22 This case study is adapted from renewable energy Technical Brochure No. 103 of CADDET (the Centre for the Analysis and Dissemination of Demonstrated Energy Technologies). Published More information on CADDET projects is available at

Solar Wonders, ©2007 Florida Solar Energy Center 23 Discussion Questions Would this home be efficient and comfortable in the U.S.? If so, where? What applications used on this home would work on a home in your community? Why? Are there are changes you would make in this house as described in this case study?