A sustainable life with profit

TIM Adams and Pip Watt live in an energy-efficient, sustainably-built house that’s warm in the winter, cool in the summer, and has no bills year-round.

Tim designed his 7-star energy rated home on approximately 7 hectares (about 17 acres) in Gherang, near Geelong, in the southeastern part of Australia, in the state of Victoria. The house is equipped with alternative energy systems in addition to various heating and cooling techniques to make the building carbon neutral and comfortable.

Tim is the current President of the Building Designers Association of Victoria, who also runs a sustainable home design business, F2 Design, to produce high performance, energy efficient homes. Tim is also an Accredited Thermal Performance Evaluator for the organization.

He became interested in energy efficiency and sustainable building design after the 1975 global oil crisis.

Tim and Pip have designed a house that has its own electricity, domestic water and sewage treatment systems.

The house has 3 bedrooms, 2 bathrooms and north facing open plan living areas with glazed walls to allow maximum natural light into the floor slab to take advantage of available solar heat.

There are no eaves at Tim and Pip’s house.

Tim said the use of eaves required careful consideration as deep fixed eaves can hamper passive thermal effects if not used wisely.

The day I visited outside it was around 13 degrees Celsius (around 55 Fahrenheit) while inside the house it was 19.5 C (67 F) and the only footwear needed was socks.

Once Tim and Pip chose to install a solar power grid system, they carefully calculated their annual electricity use and arrived at an average daily consumption figure of 9.25 kilowatt hours.

They reasoned that a three-kilowatt solar PV grid-fed system would capture enough sunlight to cope with its use and produce excess to sell to the grid.

The house has a photovoltaic solar energy electrical system that consists of a three kilowatt inverter with 18 solar panels of 180 watts each.

Tim said that when they installed their solar power system there was a state government feed-in rate of 66 cents per kilowatt hour for alternative energy systems, so he agreed to a 15-year contract at this rate with his power supply company.

“The first electric bill in three months with the smart meter in place delivered a $205 credit, even though the average daily sunshine last summer (2010) was 1.5 hours below average,” he said. Tim.

The Adams have a normal range of appliances including a kettle, toaster, microwave, espresso machine, oven, induction hob, full-size dishwasher, fridge, front-loading washing machine, and a variety of entertainment equipment.

The wide V-shaped design of the roof is an important part of the solar energy system of the house.

The northernmost orientation of the two roof sections is sloped to position the solar panels for maximum exposure to the daily passage of the sun.

The idea behind the roof design is worth examining further as being inverted means people are protected from serious injury as any fall means a slip on the long roof gutter, not on the ground 4 meters further down.

Tim designed the roof’s single-box gutter to be wide and deep enough to efficiently collect the rainwater needed for domestic use.

Cleaning it is also easier than a conventional gutter, since it’s wide (Tim calls it his training pool) and can be easily swept and debris removed quickly.

Tim and Pip have plenty of space on the roof of three buildings that act as catchments for their 120,000-liter (26,374-gallon) rainwater tanks.

Hot water for a floor slab heating system comes from 60 roof-mounted solar evacuated tubes plus the back-up of an Italian combustion boiler with a high-efficiency heat exchanger.

To allow internal temperature control, the house faces north and there is no under-slab insulation.

Placing the concrete floor slab directly on the ground allows for a cooler slab to be chosen on warmer days.

To encourage more cooling in hot seasons, the house incorporates cross-ventilation design principles and employs other devices, such as temperature controlled window switches, ceiling fans, and an evaporative water feature designed to channel cool air into the interior. inside.

The house is a 7-star energy rated building due to the fact that only the south side is equipped with double-glazed windows.

There is insulation in the walls and ceiling with standard R3.5 rated insulation batts (R rating in this case means approximately 160mm (6 inches thick) of batts).

The house is essentially a square-shaped building with main supporting walls of plastered brick and windows clad in planks of native plantation wood.

The yellow stringy bark planks that clad the house were produced using an innovative radial-cut process and sustainable farming methods to reduce environmental impacts and waste.

Tim explained that the most expensive outlay they had to make to build their house was a worm-based sewage treatment system.

This cost $10,000 Aus. to install and has a $300 annual service fee, but they figured this expense would be offset by the savings they get from owning their own power and water systems.

Tim said that for a long time he had wanted to build a sustainable design house to test his design principles, but also to show how profitable it was to build such a house.

“I wanted to be able to build a new house and really put my money where my mouth is,” Tim said.

“I made this (design) to use as an example.

“You can do this kind of thing (build a sustainable house) without spending a lot of money.”