Our sustainability journey

In the dark ages of the mid-noughties when my wife Leeanne and I started our sustainability journey, the average solar panel system was 1kW and that cost an eye-watering $12,000.

Thankfully, the Federal Government helped support early adopters to make the change. After all the rebates and grants our first home sustainability upgrade in 2009/10 cost us $14,500. This was helped by a $10k, interest free, Green Loan.  

We installed a vacuum tube solar hot water system, a 2kW solar PV system. and a stainless steel rainwater tank. Back then, the feed-in in tariff (FiT) was 66c/kWh!

We wanted to spruik our newfound sustainability to everyone so we hosted the CSIRO’s Energymark series of community workshops at home in 2010 to explain climate change and the necessary transition from fossil fuels to renewable energy. We also ran workshops on composting and worm farming and opened our home to the public for Sustainable House Day in 2010, 2011 and 2012.

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After moving to Empire Bay, on the NSW Central Coast in December 2016, we decided to increase the size of the 1.5kW PV system on the pre-existing home we bought to 6.5kW. The roof was perfectly oriented due north. That cost us $4,000 in late 2017.

When we moved to Bundanoon, in the NSW Southern Highlands, in December 2019 we were immediately thrown into the bushfire crisis, along with all the residents of the Wingecarribee Shire. We evacuated twice. The wonderful community of Bundanoon welcomed us and we were soon helping care for the surviving wildlife.

In February 2020, we installed a 13.2kW/10kW (panels/inverter) which cost $8,000.

The following year we planted 285 native Australian plants to provide habitat for our local fauna.

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We've learnt a lot from carrying out these three home sustainable retrofitting exercises over 13 years. Initially, we were motivated to reduce our greenhouse gas (GHG) emission footprint and to take advantage of the generous Government grants and that huge solar feed-in tariff (FiT).

Roof orientation and the number of roof surfaces is extremely important. A single roof surface facing due north is by far the best location for PVs.

Maximising the installation size is essential to get the most out of your system. You can install one third more kWs of generation than the inverter rating. The benefit of “oversizing” your system is to enable more generation in the morning and evening during winter.  During summer, you’ll get even more generation and the inverter will clip at 10kW but that will be infrequent in most cases.

We also learned that many PV installers will want to sell you the most expensive system they possibly can. However, the electrons aren’t any better if you buy a more expensive system, so I don’t believe there is a significant benefit to the householder from an expensive system.

I always ask for a budget system quote. So far, none of the three installations we’ve bought, or the two others I’ve assisted, have had any serious problems. Also, microinverters are only of benefit if your roof is intermittently shaded all day, every day. In general, a standard, wifi string inverter is more than adequate.

Batteries remain uneconomical. We use the grid as a virtual battery. There is a premium to pay when importing electricity from the grid, but this is far less expensive than the cost of installing a battery.

In our case, since the price increases on July 1, we pay 36c/kWh and our FiT is 12c/kWh. Ultimately, once the grid is upgraded to handle bidirectional EV batteries, EVs will become integral to the stability of the grid.

In September 2022, we replaced our eight year old Mazda CX 5 with a BYD ATTO 3 Extended Range EV. Other than the published range being way over specced, it has been fantastic!

We decided not to install a home charger because our driving patterns meant that by simply plugging in to a standard power point we could charge one third overnight. That is perfectly adequate for us. We save about 80% on the running costs compared with our old CX 5.

We then purchased battery powered garden and lawn maintenance  equipment including a mower, line trimmer and leaf blower.

Recently, getting off gas has been front and centre for us. However, the cost to do that can be quite daunting.

In July, 2023, we finally decided to replace our 900cm gas cooker with a ridiculously expensive induction cooker. That, and the necessary rewiring to handle its large power demand, cost $8k! (You don't have to spend as much as that on an induction stove though - Ikea has portable single induction cooktops for $69).

We no longer use the gas heater in our living area. Our only gas use is for instantaneous hot water for two showers daily. The high cost and low GHG benefits of replacing it with a heat pump just weren’t worth it.

We have continued our outreach by joining not-for-profit Wingecarribee Zero Emissions (WinZero).  WinZero “was an idea that began under the haze of the 2019/20 bushfires (that) came together during the global pandemic and will continue on for decades”.

Their goal is “to achieve net zero carbon emission for the Wingecarribee Shire by 2050, if not before”. WinZero’s latest project is Fossil Off!, aimed at getting households in the Shire off gas by 2030.

Win Zero is working closely with the Wingecarribee Shire Council on a new initiative called Good for the Hood, with a mission to “empower Australian individuals and organisations to create positive environmental and social change in line with the UN Sustainable Development Goals.” They offer workshops on a range of topics including: reducing food waste, composting, solar power, EVs, cloth nappies and sanitary products and low impact beauty and cleaning.

So, in a nutshell, that’s our sustainability journey. I encourage you to follow suit where possible.