Sustainability Case Studies

Sustainability Case Studies

Flinders Sustainability Group
Sustainability Case Studies
The “Grey House”
dscf1206[1]The “Grey House” is a recently-built Flinders house, constructed with sustainability issues front and centre. The owners have described the house and its features as follows:
“The 90 foot wide block allowed us to site the house across its width, rather than lengthwise, to have maximum north-facing exposure of the living areas. The north-facing rooms have large windows and glass doors, and we have wide eaves to ensure that the sun can penetrate deep into the rooms in winter, but is cut off in summer. We have double glazing throughout.
“A key aspect is the use of internal masonry walls and light external cladding. The masonry walls are Besser brick, back-filled with concrete. They completely line the large living room and kitchen and, together with the slab floor, act as a large thermal mass for levelling out temperature fluctuations. The light external cladding (corrugated iron and Hardieboard) allows heat to readily escape and not build up during summer. High rating rock wool insulation is used in walls and ceiling. An exhaust fan is installed in the roof at the southern end and is used to extract heat from the roof cavity in the hotter summer weather.
“During winter, the main heating is a Coonara wood heater. Reverse cycle air conditioners (heat pumps) are installed in the living room and main bedroom but are not often needed. We have 18 PhotoVoltaic panels installed, providing 3 kW (peak) of electricity. The excess is fed into the grid and more than pays for our power. We receive the Premium Feed-in Tariff and are currently well in credit to the power company.
“Toilet water and water for the garden is supplied from two tanks, with a total capacity of 17000 litres. Hot water is supplied from a Qantum heat pump, for which for which the running costs (electricity) are less than one third of those for a conventional electric HWS so it will quickly pay for itself.”

The “Monie House”

img_2474[1]“Having installed a Solar hotwater system in 2002, we decided to become more sustainable with a 1.6 Kw Photo-voltaic system in 2005. To ensure greater independence from the electricity grid, we installed a battery system which ensures we have light for some days independent of the grid and gives us limited power options as well, particularly for the Fridge/freezer.

Since our house was built in 1979, it has inadequate seals and insulation and of course does not have double-glazing; this we are planning to rectify, but retro-fitting is difficult.

For the garden (including vegie garden) and some household requirements, our water-tank capacity of 36,000 litres is adequate except in the case of prolonged drought. For the garden we have a computerised watering system which ensures watering in summer even when we are absent.

For heating, we use a fan-less wood heater which is adequate for the living area and we do not heat bedrooms. We have a back-up heater/airconditioner (reverse-cycle) which is rarely used.

We joined the Premium Feedin Tariff (PFiT) gravy train in Sept 2011 after 17 months of haggling, meter changes and general bureaucratic inertia. But, to given Origin some credit, they have back-dated everything to May 2010 which was when we applied”


The “Trahair House”

img_2541In March 2002 the Trahairs installed a 2KW photo-voltaic (PV) system, possibly the first in Flinders to install solar power. Their motivation was pollution reduction, never expecting that their investment would bring a financial return. They also installed a battery system, so that they would be less dependent on the grid – outages were very common in those days.

Solar hotwater was installed at the same time.

In 2008, they installed more PV panels, and in November 2011 brought their system up to 4.9KW, the maximum allowable for a domestic system wanting to claim the Premium Feed-in Tariff (PFiT). They have recently signed up with Lumo after AGL who, after five years and without notice, ceased to accept the presence of their solar export meter installed in March 2002.

Double-glazing was installed in all windows except those facing north.

They have installed rainwater storage of 18,000 litres and are virtually independent of the reticulated water supply. They have been connected to it for emergencies but rarely has it been necesary to use reticulated water. Instead of a septic tank they installed a worm-waste sytem for all household waste, excluding plastic, stone and glass; this system, like the many others in the Flinders village and elsewhere, made it unnecessary to connect to the recently established sewerage system.


Sustainability – Looking for More Case Studies

The FCA is interested in what members are doing to increase the sustainability of their households. There are many approaches to this: reduction of power and water use; generation of renewable energy (most often solar arrays and/or solar hot-water); installation of water tanks; installation of improved insulation and/or double glazing; installation of wind turbines; other innovative approaches.

If you have done any of these things at your Flinders’ address, we would be interested in a quick report from you. We are planning to write-up a few case studies of people’s experiences, highlighting difficulties encountered and assessment of results – these would only be published with your agreement, of course.

Please send your initial short report to Peter Monie (convenor of the Sustainability group) at or ring on 5989 0539.





Your Association (FCA) has set up a group to work on ways to bring about a greater degree of energy saving and, hopefully, renewable energy production in our area. Individuals and Households can achieve a great deal without waiting for governments to act.


MPS Group Buy Scheme

The Mornington Peninsula Council has published its list of preferred suppliers for Solar Hot Water and Rain Water Tanks as part of its Group Buy Scheme. More information can be obtained by going to the MPS website:
We hope you will consider one or both of these for installation at your place in Flinders. There are rebates available which are particularly attractive for the solar hot water option. You can ring the Council on 1300 850 600 to register your details and mention the Group Buy Scheme.


Solar Feed-in Tariffs

For those of you with PV solar cells and connected to the grid, Victoria has introduced a feed-in tariff of about 60 cents per kw hour. You should contact your retailer to make sure you receive this rate. You may be interested to read Moreland Energy Foundation’s assessment of the various electricity retailers’ offerings.

Since the FCA’s AGM, at which a loose-knit group of more than 100 people called “Power Partners” was mentioned, we have been in touch with the Convenor, Peter Strickland, of Balnarring. There were articles in the Age recently which dealt with some of their concerns.
Click below for article:

If anyone wants to join the “Power Partners” email list, write to Peter and Kathie Strickland

In Flinders, Mark Aarons has been trained as a Household Energy Assessor; he can be contacted on 59890881 or email:

For more information, or if you would like to join the Flinders Sustainability Group, please ring Peter Monie 59890539 or email to: or ring Tony Stafford on 59890602.