I've given some thought as to whether to post this, it's arguably getting a bit off the point of the thread, but I've decided to go ahead with the intention not of arguing but of, hopefully, elaborating on why others have reached the conclusions they've reached.
My real point here not being about the detail of energy production but rather, the overall climate debate. The facts and figures are the basis of my point, but the point itself is the debate and climate.
In the context of running a single house in that part of NSW I don't doubt that an off grid solar PV system can work. FWIW the energy industry itself wouldn't doubt it either - for the record there are oil fields pumping with solar power and there are hydro headworks operated by solar too. So even the "traditional" energy industry is more than happy to acknowledge that the technology works.
But to put some figures on it, there are 688,220 rooftop solar installations in Victoria, data current as of earlier this year so would be a bit higher now. The capacity of these comes to 4,733,666 kW so that's an average of 6.936 kW per roof which is a substantial system.
So how's it going?
Over the last 12 months these solar systems generated 5037 GWh of electricity.
Over that same period Victoria used 47,658 GWh of electricity, plus 54,722 GWh of gas (not including gas used to generate electricity so no double counting), plus 2778 GWh of LPG, plus 100,860 GWh of liquid petroleum fuels, plus 7027 GWh of biomass in various forms (including firewood).
Now looking specifically at yesterday, 3rd June 2024, the figures are typical for winter:
The rooftop solar panels generated 5.7 GWh, 59.7% below their average daily output.
Electricity consumption was 150.6 GWh, 16% above the daily average.
Natural gas consumption, not including gas used to generate electricity, was 200.3 GWh or 34% above average.
Then there's the petroleum fuels which, given it's a working weekday, were also likely above average. Even at the average level though it's still 284 GWh per day including LPG.
That reality is stark. There are 2,810,775 homes in Victoria, not all of which will be suitable for solar due to shading, roof types, high density apartments and so on and we've already got solar on almost a quarter of them. And yet all that did, today, was supply 3.78% of the state's electricity or approximately (making assumptions about liquid fuel use) about 0.87% of total energy.
No matter how you slice and dice that, small scale is not of itself going to replace fossil fuels in Victoria or indeed most places. No amount of plausible improvement in energy efficiency is going to close that gap.
Now here's where it gets to the crunch.....
Tell some engineers there's a problem with fossil fuels and we need to stop burning them and they won't fail to realise what I've just written, if there's one thing engineers do it's crunch numbers. That being so, we know what comes next - they'll start looking for places where large scale projects can be built. They'll look for places with particularly good wind resources that could be easily developed. They'll look for steep, narrow pinch points on rivers where dams could be built for hydro. They also won't fail to realise that a single 4 unit nuclear power plant could of itself generate 115 GWh per day. And they'll be well aware that a high capacity transmission system will be required in order to connect these to each other and to major loads eg Melbourne.
The trouble being, there isn't anything approaching universal support for actually building such things and this is where it all gets confusing. It's the crux of the point I'm trying to make here.
On one hand there's an argument put forth that there's a problem, an actual crisis, relating to fossil fuels.
On the other hand there's a rejection of large scale measures to end the use of fossil fuels. With the twist that those rejecting such measures include many of those saying there's a crisis.
That leaves the engineers stunned in amazement, and it leaves their managers thinking they'd better keep well away from all this since they've no idea how to handle it. And so the reports are buried and replaced with a seemingly safer plan to burn gas instead.
It also leaves everyone involved pondering just how real the crisis actually is if those most concerned about it are rejecting solutions to it? What do they know that the rest of us don't?
Personally I'm in that situation as are many. Go back 25 years and, having heard what was being said, I saw it as the greatest problem facing humanity. Today I'm far less convinced and that's the reason why, I've seen so much consistent rejection of solutions, by those who scream the loudest about the problem, to not have doubts about it all.
Now realise people right up to very senior positions in politics and business have seen and heard exactly the same with their own eyes and ears. They know that any major solution will be rejected, so they're not going to make the mistake of proposing one. Instead they're going to propose modest efforts to cut back but that's where it ends.