Luciferase,

"Free energy" isn't my mantra, and my objection to Prieto and Hall's figures isn't because they destroy any mantra of mine, but because they're so misleading!

Far from being "the only voice of real, experience in mass PV installations", Prieto and Hall's figures are distorted to the point of uselessness. Pretending their figures are the true EROEI is fraudulent. I repeat: FRAUDULENT! But that doesn't mean I want to ignore P&H, it means I want everyone to understand the fundamental flaw in their methodology:

MONEY IS NOT ENERGY! Prieto and Hall's conversions are based on the average amount of energy it takes to make a certain profit. But in reality the amount of money in circulation depends on how much banks lend, not how much profit is made. So financial inputs don't have an energy equivalent.

The unbuffered figure is the appropriate one because it makes sense to go for the low hanging fruit first. There's plenty of opportunity to replace fossil fuel. According to an SMH report I read yesterday, SA's already getting an average of 40% of its electricity from renewables. Yet there's no grid level storage in SA.

Eventually of course we will need storage. But by then EROEI is likely to be much too high to be of any concern (if it isn't already).

Lending cheaply to finance renewables will probably be revenue neutral, but will definitely reduce electricity prices. There's no way the public purse can't afford it. Meanwhile nuclear's far from cheap.

And until this post I never mentioned Elon Musk.

Spencer, domestic PV is very much viable, although it is a little costly at present. That cost is going to plummet very soon. I'd go further and say that domestic (and rooftop commercial) PV is essential, especially when combined with storage and interactively controlled grid connection (smart grid).

Some (by no means all) important reasons are:

1. It reduces the need to design reticulation systems or central generation systems for high levels of peak demand. Therefore, there is a large efficiency dividend from highly distributed systems.
2.It smooths the supply fluctuations due to variability of sunlight. The more widespread PV is, the less a local clouding event matters. Especially with storage to buffer the grid connection.
3. It allows the widespread adoption of HVDC reticulation which adds to the efficiency dividend discussed in 1.
4. It allows for the ready adoption of more efficient DC motors in domestic appliances.
5. Properly broad adoption of PV will include the rollout of new technologies, including dye-sensitised coatings, perovskite-based films and so on that operate well under low ambient light and are hence useful for recapturing energy within homes and in shaded areas.
6. It provides a demand base that allows large scale manufacturing at efficient scales, driving costs down.
7. It drives industrial development servicing, installing and designing the technology and new technology that is enabled.
8. It provides resilience against natural disasters damaging reticulation systems. Cyclone Ada, that hit Cooktown a little while back knocked out power for 3 weeks. Similarly, the cyclone that hit Rocky earlier in the year knoocked out power for some time. One of Nepal's major problems is lack of power after their earthquake.

A systems approach is needed and rooftop PV has to be a large part of that.

Aidan, you make a good point wrt money and energy. It seems to me that a large part of the problem with our present economic model is that money is decoupled from energy. If it were more closely coupled, it could represent a useful feedback mechanism to enable close control of financial and trading systems, rather than acting as an arbitrage mechanism that allows for positive feedback and hence destabilises the operation of markets (and distorts calculations of value).

Craig,

You may be right. I was referring to current solar which is not competitive with large-scale renewables for cost of emission abatement, breakeven timeframe, or return on investment compared to large-scale renewables.

The cost of emission abatement for the small-scale renewable energy scheme has been put at $100 to $200 per tonne. Large-scale is more efficient (though it incorporates wind and hydro so not a direct comparison with PV, but a comparison in the sense it is an alternative).

On the provision domestic solar and batteries reduce in price significantly, and likely increase in efficiency, then an off the grid house would be preferable, because around 70% of Australia's electricity costs are from the distribution grid and retail mark up - this is why it is good to compare a year of electricity bills to the cost of domestic PV for an estimate, rather than comparing to the cost of wholesale electricity.

However, there would need to be a significant breakthrough in both battery technology and PV solar efficiency. I've done off the grid cost calculations and considering you need to consider having enough storage for at least a week of no sunlight, a backup generator big enough to power most of an average home, and a pretty big solar system, the cost is so prohibitive that the take up rate would struggle if the price was a third of what it is now.

Additionally to get rid of the distribution system requires everyone to have that system, which is highly improbable. Therefore large-scale is preferable to domestic from a costs/breakeven/ROI point of view.

Moreover, areas of high electricity usage per square meter, such as in the CBD would not be able to rely on solar off the grid. So small distribution networks would still exist even if every household was off the grid.

I know much of this wasn't your point. Domestic solar is growing pretty quick, and is one of the three biggest reasons for declining electricity usage in the network. So, it is working in that sense, and people are free to pay for good feelings

Spencer Wright,

You are displaying denial and intellectual dishonesty. Am I correct you are dodging this: http://forum.onlineopinion.com.au/thread.asp?article=17320#306836 and diverting to other subjects you'd prefer to discuss because you know it is correct and explains why your pet idea is economically irrational and would deliver no net benefits?

As previously mentioned, I will not engage with you.

Considering you have drawn the conclusion that a provision in legislation is merely my belief demonstrates that you are a cockroach that trolls the internet.

If anyone else wants to ask me the same question I really want to dismiss these false and misleading statements.