ALTRAV, communities can form their own co-ops and provide their own electricity for distribution within their membership and export excess at market rates. Have a look at Saturday's ABC Landline program: http://www.abc.net.au/news/2018-04-07/people-power:-communities-funding-their-own-wind/9630150 :-)

ALTRAV, regarding your opinion about solar PV owners losing out on the monetary equation, I'd like to point you to this article published in the Finder on March 7, 2018: https://www.finder.com.au/9500-solar-panels-installed-every-day-in-australia :-)

In order to achieve a balance, as requested by the originator, I am posting links to three recent article in the RenewEconomy that specifically address issues raised here:

https://reneweconomy.com.au/tesla-big-battery-is-changing-the-way-people-think-about-the-grid-15923/
https://reneweconomy.com.au/low-income-and-disadvantaged-households-should-be-priority-for-clean-energy-68313/
https://reneweconomy.com.au/solar-pv-wind-track-replace-coal-oil-gas-within-two-decades-21333/

I encourage all of you who answer "No" to Geoff Carmody's question, "Can we afford a renewables-only power supply?" take the time to read the articles above for a balanced perspective. Thanx. :-)

GJOESQ, these articles are skewed towards renewables. We are nowhere near relying on renewables yet. I totally reject any comments/articles/surveys promoting renewables. The current technology is ideologically driven by un-informed and mis-informed people. The latest attempt at pushing sh!t up-hill is ridiculous. Lets look at the current state of the dreamers plans. We begin with wind. Total failures. Any form of machinery used in this fashion is going to fail. And they are, constantly. Solar also a failure but for different reasons. Now they want to throw another bad decision after so many before them. The best way to describe why these are not viable is; imagine an aircraft where the engines are the size of the fuselage and it could only carry four passengers at a time, because the engines were so heavy that it could only carry the weight of four people. That's a reasonable comparison of the efficiency of renewables at present. Then the idea of batteries. A band-aid solution at best. The type of power generation we want/need has to be continuous and at base load levels. The other negative is visual pollution. No one has talked about the size of these wind and solar farms. They will be, at least, double the size of the area/city they will service. You can read, link and refer as much as you like, you and your clan are on a road to nowhere. So, NO! We cannot afford a renewables-only power supply.

GJOESQ, as for your comment on 'selling the excess power to the community at market rates'. You cannot just come 'off the grid', because you say so. Like your sewerage system, once the service goes past your front gate, you start paying. The one thing everyone must pay is for the privilege of having the service 'just being there'. Whether you connect to it or not, you may not pay a 'usage' fee but you pay none-the-less. And as for selling it to the community. Not in this country. You cannot have it both ways. Either you stay on the grid and get nothing other than a cheaper electricity bill. Or you try and get off the grid and find out you can't. Again dreaming. I've explained that you will be subsidising the energy provider by injecting free power into the grid which they will on-sell. You might get a cheaper power bill some months, but they get free power from your SP's and on-sell it to consumers. They will not repair or replace your SP's, you do at your expense. So you will not benefit financially with your extra power. This was the plan from the start.
Big market push, offer big incentives in the form of financial refunds or rebates. Making sure there is a sunset clause and they will cease the incentives. When that happens, the electricity providers will be getting free power from your SP's which they will on-sell to the community. I don't think people thought that one through.

GJOESQ,
The problem with batteries is that they cost a lot more than
the renewables they are designed to support.
At $1 trillion plus they do not generate 1 watt of electricity and in
fact they lose 30% of what they are charged with.
That will never improve more than a tiny amount because the laws of
physics says that when you change energy from one form to another you lose some.
Do you have any idea of the size of the task to install 6000+ of those batteries ?

It is just the way it is !
You are right in that it is possible to go off grid on the scale of
domestic housing and even small factories, but I presume you will
still want to eat. The processing of food and refrigeration are
beyond a few solar panels and batteries for supermarkets.
And that is just one industry, what about all the others ?

It is these fundamentals of physics that has doomed the dream.