Our architect designed eco-house was purpose built in 2002. Its 243.7 square metre (2,623 square foot) footprint comprises the 158.3 square metre (1,704 square foot) main house, the 24.8 square metre (267 square foot) sunspace and the 60.6 square metre (652 square foot) guest wing. It’s one of the most thermally efficient houses in Tasmania. It’s off the electricity grid, and indeed independent of all services except telephone and internet.
Onemilebridge is independent in electricity production – due to our stand alone (i.e. off the grid) electricity system. Here are some facts about it:
Electricity is generated by photovoltaic panels on the roof. They are made in Japan by Kyocera. We have 12 panels which each generate 130 watts, equating to a 1.56 kilowatt array. The panels lie on the 15° roof in summer (when the sun is high in the sky), and they tilt up to Mole Creek’s latitude 41° in winter (when the sun is lower in the sky). The panels (and the house) face due north to maximise direct solar exposure.
All of the remaining hardware is in a purpose-built battery room directly under the panels.
The 48 volt direct current electricity from the panels is stored in a lead acid battery bank of a total 1,000 amp hour capacity. Each battery is fitted with a hydrometer so it’s easy to check which battery needs topping up with distilled water and when it’s been topped up enough.
The Selectronic inverter converts the 48 volt direct current into 240 volt alternating current which passes through a bank of circuit breakers on its way to the house and the guest wing.
The system is monitored by a Trace meter in the kitchen which displays in real time how close the battery bank is to full charge, the net difference in amps between electricity generation and use, and the number of amp hours the battery bank is below its 1,000 maximum.
To ensure long battery life, we don’t allow our battery bank to discharge below 70% of full charge. So when it reaches 70% we run a backup generator. We only need it for a few hours each year – mainly in May which is our cloudiest month. Generator use could easily be reduced by adding more photovoltaic panels to the array.
Electricity-wise we run a totally normal house – with appliances including cyclical defrost refrigerator, chest freezer, toaster, kettle, washing machine, laptop computers, printer, and fax machine. The range of electrical items we use is not at all influenced by our stand alone electricity system. The only difference is that we don’t have any electricity bills.
Sharing the cooking and serving of food have got to be amongst life’s chief pleasures. Especially with a view of the bush through the kitchen window!
Although we mostly enter and leave the house through the laundry, the kitchen door seems to be in perpetual motion. In and out to pick herbs or to catch a moment’s rest on the kitchen deck, to welcome the sun with a cuppa, or to farewell it with a glass of wine.
The kitchen has room for two cooks, with plenty of storage for all their equipment. The central island bench was made to our design (out of sycamore of course, to match the cupboards) and is on wheels so it can be pushed against a wall or wheeled into the dining area to serve as a buffet.
As our house is about 27 km from Deloraine’s Woolworth supermarket, and as we store bulk food – including 25 kg bags of flour for bread baking, and jars of home-made jam – we have a large pantry. It’s adjacent to the kitchen, and on the house’s southern aspect which keeps it cool all year round and especially cold in winter. It has abundant sycamore shelving, and bench space with adjacent electricity.
The pantry also contains the refrigerator and the microwave oven.
Having enjoyed this pantry for about nine years, I can’t imagine living in a house with a small pantry.
I’m proud of the personality-filled dresser that sits against the wall in the dining area, but still we try to sit guests with their backs to it so that they face out towards the view. The view is, after all, the star of the show here, with diners having ring-side seats to the passing weather and animal antics of Home Paddock.
We probably use this part of the house more than any other. It’s between the kitchen and the living room, so it’s possible to sit here and chat with the cook while sipping on a drink and perhaps shelling the peas.
The living area, at the north-western corner of the house, begins where the dining area finishes.
This area changes character depending on the season. In winter, we light the wood heater and turn inwards to watch its flickering flames. On a sunny winter’s day sun pours in through the double doors that lead out onto the terrace to the north of the house, making the sofa the perfect place to relax with a book.
In summer, the eaves prevent any sun from entering the house and attention turns outward towards the view, and we move away from the heater. There are double doors here that give onto the sunspace, providing a cool breeze and indoor-outdoor living.
This was intended to be nighttime or winter room, a cosy internal nook, a retreat for quiet reading. It turned out to be all that but also a lovely cool place to sit in summer and enjoy the view, as well as a spillover seating area when we have larger groups of visitors.
For some reason it’s just about the best place in the house to enjoy the view – even though all the northern rooms have large windows overlooking Home Paddock and the bush beyond. Maybe it’s because this room is further back and gives a different perspective. Or maybe it’s because you can see through several windows at once – including the double doors of the living room.
