My Off-Grid Solar Power Solution
Solar Power – The Environmentally Sustainable Energy Solution
The sustainable energy solution I’ve implemented (care of Roland Lawrence) is 100% electricity – in the form of Solar Panels and a battery.
My costs and projections page with all the information about costs and payback periods has old information on it. But I will update it soon I promise.
Solar panels on my front roof
I live in a heritage conservation area and that means I’m not permitted to put solar panels on my front roof. As you can see, the home solar system we have designed uses the front roof. If I want to be 100% self-sufficient with energy then I need to use as much roof space as possible. I am 100% on board with maintaining our heritage, but at this stage of the climate emergency, I think the costs of not being able to implement a temporary structure that can be removed outweigh the requirement for aesthetics.
I am extremely lucky to live in Sydney’s inner-west area and the Inner West Council is committed to moving to zero net carbon emissions. So I am hoping they will be supportive of my request when I lodge the final DA (maybe around Christmas 2025). I would be extremely grateful if you would sign my letter to the council asking that they consider my request for panels on the front roof given we are running out of time to tackle our emissions crisis.
Solar Power vs. Natural Gas
What is the environmental impact, and why did I choose solar power? Before we get into more detail on my sustainable energy solution, I wanted to outline the 3 reasons I chose solar power over natural gas.
1. Research shows households are likely to generate fewer emissions using electricity when compared to gas, particularly in the future. This is what Renew Magazine wrote in their article ‘Emissions intensity of household electricity vs gas’:
“Renew’s research, along with existing studies and academic literature on household fuel choices, demonstrates a strong case for home electrification. The data from this study shows that throughout the NEM, most households would generate fewer GHG emissions when heating with efficient reverse-cycle air conditioning instead of gas units.
“Although gas, hot water, and cooking appliances still produce lower emissions than their electric equivalents in most areas, the difference is increasingly marginal and, because the emissions intensity of electricity networks will continue to decrease into the future, households making the switch to electric appliances today are investing in a low-emissions future.”
2. Gas is not renewable and it’s WORSE than coal for global warming. The sun’s rays aren’t going to run out and we don’t have to dig up the ground to extract energy from it. The Climate Council writes:
“It is true that gas, if produced and consumed in Australia without being liquefied, is 30-50% more carbon-efficient than coal at the point it is burned to produce electricity. But this benefit is substantially eroded by the emissions created when gas is vented or flared during the exploration, extraction, transport and distribution processes.
Gas is mostly composed of methane, the most significant climate-warming agent after carbon dioxide. Methane survives for a shorter period in the atmosphere, but over 20 years has 86 times the planet-warming potential of carbon dioxide.
In 2019, the venting and flaring of methane accounted for 6% of Australia’s emissions – and this is likely a significant underestimate. These so-called “fugitive emissions” massively detract from the purported climate benefits of a gas transition.”
3. I want energy security, I don’t want to rely on the grid. (I will also have a solar battery for this reason). We know that climate change was in part responsible for the worsening fire conditions (despite what Barnaby Joyce says – I prefer to get my information from the experts). If the bushfires over the coming years get worse, I’m not convinced our leaders are well-positioned to stop our energy grid from burning down.
My Solar Power Solution
Off-grid solar power system
Solar array: 9.135 kW
Panels: 21 panels (18 REC Alpha Pure-R + 3 WINAICO WST-525NGX-D3)
Solar array layout:
• W1 – 250° orientation – 23° tilt – 4.2 kW – 10 panels
• E1 – 69° orientation – 23° tilt – 1.575 kW – 3 panels
• N1 – 340° orientation – 30° tilt – 3.36 kW – 8 panels
⚠️ This setup is meant to include 8 more panels on the front roof — but due to heritage restrictions, I haven’t been allowed to install them… yet.
Inverters: Fronius SCERT-5.0-1 + Selectronic SP Pro
Battery storage: 6 × PowerPlus ECO4840P = 24 kWh total
Charge controller: Victron MPPT 250/100
Monitoring: Select.Live
Estimated annual generation: ~11,368 kWh (~31.1 kWh/day)
Estimated daily usage: 17 kWh
Estimated self-sufficiency: 98% (I’m going for 100% obviously…so I gotta get those kWh down!)
CO₂ savings: ~3.6 tonnes/year
System cost: $54,499.99 (after STCs)
Once I get approval for those 8 front roof panels, I’ll be one big step closer to genuine 100% energy self-sufficiency year-round.
Curious about solar?
If you want to get a quote:
SolarQuotes is a great tool — not an ad, just genuinely useful.
If you want to explore your home’s solar potential:
SunSPOT lets you model what’s possible based on your location and roof orientation.
Battery safety and the fireproof bunker
My home is made of timber. After more than eight years of building it, I’d really prefer it didn’t burn down. That’s why we built a fireproof bunker to house the batteries.
Bunker features:
• Fully lined with compressed cement sheeting (another compromise on my sustainability goals)
• Access hatch for maintenance
• Interlinked hardwired smoke alarm
Purpose-built to house:
• 6 × PowerPlus LiFePO₄ batteries
• Fronius inverter
• Selectronic SP Pro
• Victron DC isolators
• Subboard and controls
Battery fire risks?
Not as scary as some headlines make out.
• Over 200,000 home batteries have been installed in Australia
• The Canberra Battery Test Centre found performance issues, but no safety problems
• Globally, there have been fewer than 400 verified EV fires across 40 million electric vehicles
• LiFePO₄ batteries (what I use) are among the most stable and safest available
More on battery safety:
SolarQuotes: Battery Safety
See my step-by-step breakdown for urban off-grid living
Everything I wish I’d known before I started
Solar Power Battery Storage System vs. The Grid
What’s better – Being plugged into the grid or having a solar power storage solution?
From a purely cost perspective? Not yet. BTW I am in the process of re-doing my calculations and costs page
But I still chose a battery because:
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I want full energy independence
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I don’t want to burn coal during blackouts
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I believe in investing in early tech to help push it forward
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And, increasingly, grid power isn’t guaranteed in climate emergencies
Batteries won’t be cost-effective until more of our grid is powered by renewables. But we’re getting there, and household batteries will be part of that transition.
Is a battery or grid connection better for the environment?
This question comes up a lot. As with everything technology-related, things change quickly! On top of that, the modelling usually assumes that the current mix of coal/renewables in the grid remains the same. To do any type of modelling, you need to make assumptions, but you should also be aware of how changes to those assumptions can change the output.
In 2024 According to SolarQuotes, on-grid home batteries do not reduce emissions. Not yet.
A battery today probably increases your lifetime emissions. Here is why:
• During the day, solar can meet most of the grid’s demand
• If enough solar is exported, fossil fuel plants can be switched off completely
• If I store my solar instead, that clean energy never reaches the grid
• The grid still needs to meet demand, and may have to turn on a coal or gas plant to cover the shortfall
• Turning on a big plant just to fill a small gap is inefficient and polluting
• At night, there is not enough stored solar to meet everyone’s needs
• Fossil fuel plants are already running by then
• Using my battery does not avoid emissions
• The best chance to cut pollution is during the day, by exporting solar and helping the grid switch off coal and gas
Right now, exporting solar is better for the climate than storing it.
But that will change. In the future, when we have so much renewable energy that the grid cannot use it all, batteries will help by storing the extra clean power that would otherwise go to waste.
Until then, the smartest climate choice is to install more solar, improve energy efficiency and export what you can.
And Renew’s Andrew Reddaway adds:
“Installing a grid-connected battery generally doesn’t benefit the environment directly, but does help to develop economies of scale in battery manufacturing and installation, which will assist our longer-term transition to a 100% renewable electricity system.”
So I am hopeful that our government will wake up and smell the smoke and materially increase the contribution renewables have to our grid and soon! This, coupled with my desire for energy security, is why I am going for the more costly battery option.
Solar Power Facts
Busting some solar panel energy myths!
People ask if solar panels are worth it. There are a few mistruths around solar power, and the myth I hear most often is that solar panels do more harm to the environment than good. Let’s look at the truth around these myths.
Myth 1: The energy that goes into making a solar panel is more than that panel will produce over its lifetime.
Fact: The energy payback time for many modern systems is probably less than 2 years. I’m expecting my system to last at least 20 years given the warranties. So it will more than compensate for that embodied energy cost.
Myth 2: Solar panels are toxic.
Fact: There are no toxic materials except for a small amount of lead used in the solder, and the use of solder is being phased out.
Myth 3: Solar panels can’t be recycled.
Fact: Currently 85% to 95% of a panel can be reclaimed and recycled.
The problem is that we don’t have the facilities to do it yet!
I found this fantastic website – CleanEnergyReviews.info – that busts the myths I’ve listed above (as well as others). They provide links to actual research, so you know it’s not based on ill-informed opinions.
Optimising Your Solar Power Home Usage
Analytics – How to maximise your solar power usage
To make sure you maximise the use of the sun’s power and to maximise your $$$ you’ll need to install a monitoring system. I’ll be tracking my solar generation and usage through Select.Live, which came with my setup. It gives me access to real-time data, so I can monitor how much I generate, store, and use, especially once I’m fully off-grid. My Dad has Solar Analytics, and he thinks they’re pretty good. An analytical system will allow you to figure out the most cost-effective time to turn on the dryer, washing machine or dishwasher. It will also help you to understand if your system is generating the amount of energy the system is supposed to and if there are any faults.
I’m still figuring out how to optimise my usage. I’ll add it all to the website when I pull my socks up and finish doing the analysis
But in the meantime this is what my Dad (aka Tony Peppercorn – yes that’s his real name!) has to say about Solar Analytics:
“Solar Analytics as the name suggests is a product that monitors your solar output and usage 24/7, using a combination of hardware and software. A module installed in the meter box monitors the output of your solar panels breaking it down into the amount consumed on-site and the amount exported to the grid. It also monitors the amount of electricity imported from the grid. It does this in real-time and sends all this data to a central server via a 4g Connection. This data can be viewed in 5 minute intervals via a web browser. Full details can be found on their website, Solar Analytics how it works.
I bought a Solar Analytics subscription at a Sydney Renew Sustainable House Day in September 2016. One of the things that impressed me was that it was a local company and also the product is vendor independent. Since then it has been pretty reliable with only occasional outages which are promptly notified by email. These seem to be mostly related to extreme weather events.
How I use it: I mostly use it to monitor time of day usage so I can use as much solar output as possible on site. I also use it to monitor the output and efficiency of the panels. I recently got some panels cleaned for the first time since installation in 2011. The increase in output showed up in a Solar Analytics graph which showed output starting earlier in the day, finishing later and peaking higher.
One thing you need to watch out for is whether you have an available slot in your meter box. Also, if you get more panels and another inverter you may need another unit and another slot in your meter box.”