What is Sustainable House Day? Sustainable House Day gives visitors a chance to inspect firsthand houses that have been designed, built or renovated with sustainability in mind as well as the opportunity to talk to owners and receive unbiased advice. Register here to attend Sustainable House Day on Sunday 17th September 2017 and to receive information in advance of the day. Once you have registered there is no need to register in subsequent years. (house addresses will only be displayed in full 2 weeks prior to the open day) In 2016 17,287 people visited 154 homes across Australia. Online and print media stories reached a targeted audience estimated at over 160,000,000 million (based on circulation/readership figures). Sustainable House Day is an event of the Alternative Technology Association (ATA). The ATA is a not-for-profit organisation that exists to enable, represent and inspire people to live sustainably in their homes and communities. Established in 1980, the organisation provides expert, independent advice on sustainable solutions for the home to households, government and industry. The ATA also produces the high-quality magazines, Sanctuary: modern green homes and ReNew: technology for a sustainable future to provide ideas and inspiration on how to make your homes and lives more sustainable all year long.
The house from planning stage, was always designed to be a sustainable house, though in essence, is a retrofit of the builder’s existing design. It is ALL ELECTRIC, with cooktop and oven (though this is not recommended for Off-Grid), plus everything else electric. The whole of the house has LED lightfittings throughout, plus running two 520 Lt fridges and a 350lt Solar Hot Water system. With the two 5kW Inverter/10-14kWh storage batteries we have split electrical circuits between the two, one supplies the air conditioning & oven, the other power & light circuits. It is really quite suitable for small split-system Air Conditioners (one or two simultaneously max). All walls are acoustically insulated, the windows are NOT double glazed, but have 10.38mm glass. The ceiling is double insulated and the roof has a Solar Ceiling ExhaustVents installed.
The solar ceiling exhaust vent is incredibly effective in creating an insulating airlock in the ceiling cavity. The solar vent is equivalent to 9, yes, nine whirly birds because of its capacity. Apart from the 12-volt brushless motor, the fan is insect proof and of galvanised steel or aluminium construction. The BEST PART about this exhaust fan is that it ONLY works when it needs to because of the thermostat within, which is set at 28 deg. So regardless of the outside temperature – the ceiling air space stays at a constant 28 deg. And this insulates the ceiling from temperature fluctuations, so the room temperature throughout the whole house is at a liveable moderate temperature from the top. This is a great cost saving on your heating and cooling.
Battery storage system
The type of battery storage unit we use are the “All-in-One” (AIO) type systems, that is, the batteries, inverter and electronics are all contained in an attractive upright cabinet. The advantage of having all components in ONE BOX / CABINET is that you are not fighting with three or four different manufacturers (battery / inverter / controller / etc) when you have a warranty problem. This was a terrible experience during the 1990s when we did stand-alone systems at that time. The owners were left without power for days or weeks. By insisting on the “All-in-One” system, warranties are handled by only one manufacturer should anything need attention. These systems also have On-line monitoring via the Internet, allowing you to watch how your system is performing, as well as the manufactures and, from time to time, enables software/firmware updates can take place remotely, along with problem solving.
The Samsung SDI All-in-One ESS is an on-grid model we are using off-grid. It has a 5kW inverter and 10.8 kWh capacity, using 3 x 3.6kWh NMC (Lithium Nickel-Manganese-Cobalt) battery modules (Allows either 7.2kWh or 10.8kWh configuration). The Samsung is connected to 6kW of BYD solar panels, which average about 27 kWh of energy harvest a day. There is also an Alpha OF-5 AIO ESS (5kW Inverter / 14.4kWh Storage) off-grid model, that we are evaluating. The Alpha uses 4.8kWh Lithium Ferro-Phosphate (LiFePO4) battery modules & can be configured to store up to 19.2kWh. These battery chemistries don’t have the same risks as the Lithium-Polymer batteries of mobile phones and other electronic devices.
Both Alpha & Samsung offer on-grid models. Energex Regulations only allow for one ESS of 5kW inverter capacity connected to the grid. However, the Grid connected models operate seamlessly with the grid, tapping grid power when your house’s usage exceeds the parameters or capacity of the battery, grid feed excess solar generation and provide power during grid outages.
Both the Samsung & Alpha model require a data connection to the internet, via modem, to allow On-line monitoring and remote servicing.
OFF Grid Living – last three years
Our sustainable house at 10 Jeffreys Road Glasshouse, is 3 yrs. old this August (Built 2014). It has never been connected to the Electricity Grid, nor Town Water or Sewerage. All our power comes from Solar Panels through Lithium-ion Batteries and our tank water needs our electric pump to bring the water supply into the house, as well as serving the Bio-Cycle sewage treatment system. (Septic type tanks).
For the first 16 months, the house operated on 2 x BYD AIO battery storage systems with a 3kW inverter and capacity of 10kWh per unit. This was replaced when the Samsung SDI AIO ESS (All-in-One Energy Storage System) 5kW/10.8kWh battery storage unit when the Samsung became available. Our second battery is an Alpha OF-5 AIO ESS (5kW/14.4kWh) that we are evaluating. There is now nearly 10kW of solar panels shared between the two ESS Batteries.
After three years of living without Energex, we have run out of power twice, due to inclement weather conditions and that is when normally a generator would be used on these rare occasions. Even on cloudy days, you can still expect to receive some power from your solar system, so it is an advantage to have the maximum amount of PV panels on your roof connected to your battery storage unit.
You do need to be extremely energy wise, if you are in an All Electric house with off-grid batteries. The oven plus a hot-plate or two will exceed the 5kW continuous Inverter power capacity. Remember that you have a limit of 5kW of inverter power to run all your electrical demand in the house, this will take a little time getting used to but is quite easily managed after a few stops and starts. If on the other hand, you are using GAS to cook and / or hot water, then 5kW inverter should be more than adequate. Those with experience with Lead-Acid Off-Grid Battery systems will marvel at the marvel at the simple function of the Samsung SDI. Improving your home energy usage efficiency is the key to living from battery storage. Residential Solar PV is the cheapest electricity. Insulation to roofs, walls & windows, low wattage lighting & appliances, Solar Outdoor Lighting, Roof Vents & Sky-lights with Passive & Active Air Conditioning are often the easiest and cheapest ways to save electricity.