Australia is the third largest market in the world for grid scale batteries, and has the highest per-capita capacity in the world; https://www.pv-magazine.com/2025/10/21/australia-becomes-wor...
Not to mention more than 200k new household batteries installed in 2025 (out of roughly 10 million households).
After all, if the highest demand is between 16:30 and 19:00 you could use batteries to store power at 12:00 and sell it at 18:00 - or in famously sunny Australia you could build enough solar panels that solar output at 18:00 matches power demand.
If batteries have a solid 9% return on investment, but solar panels have an even better 12% return on investment, panels will outpace batteries even though the batteries are a decent investment.
(Also, from a politican's perspective, making batteries highly economical is how you get batteries built. And an awful lot of pro-environment policies involve raising taxes, banning things and creating new chores; it's nice to have some green policy announcements that actually benefit voters in the short term.)
No you could not. For half the year the sun has set by 18:00.
It's not entirely due to the apparent size of the sun — refraction due to the atmosphere has a slightly greater effect.
(Singapore is also in the 'wrong' timezone. The sun sets around 7 pm every day, giving it effectively permanent daylight saving time.)
But regardless, Australia is not near the equator. The timezones are mostly ok. In most of the country (for most of the population anyway) the sun sets before 18:00 for roughly half the year. No amount of solar is going to power the evening peak demand without storage.
> If batteries have a solid 9% return on investment, but solar panels have an even better 12% return on investment, panels will outpace batteries even though the batteries are a decent investment.
Sorry, normally I hate this follow-up on HN, but can you share a source? I tried to Google for sources, but there is a pretty wild range of ROI in different countries/regions. My point: Ideally, can you provide personal/anecdotal experience, or something that is specific to a country or region?EDIT
I forgot to say: I like your idea of intraday arbitrage using batteries! It is a very cool idea. Surely, this could be well modeled to know your expected ROI before investment/build-out.
Fire control in Australia is first and foremost about limiting spread - the bush in Australia goes off if it catches hard.
"Mini" pumped hydro is a thing here (in places): https://www.abc.net.au/news/2024-12-01/australian-first-mini...
Are they a hoarder of old car batteries and the like?
If you know your way around high voltage DC, got a tractor and appropriate emulator - not exactly difficult or super expensive to pull off.
Granted it's pretty uncommon setup as grid batteries themselves are pretty cheap too and used EV battery is simply too large for home user, too much hassle, liability, etc to save like $2-3k.
Here are two of SA's (which has the most renewable generation): https://en.wikipedia.org/wiki/Hornsdale_Power_Reserve https://web.archive.org/web/20220523164905/https://www.elect...
They are super economical in Australia and the government even offers discounts and interest free loan of 15k to buy them.
the gov't also offers interest free (but inflation indexed) loans to tertiary education.
Just because there's a subsidy, doesn't mean the tax payer is paying a price for inefficiency. The policy itself needs to be individually examined to determine whether it's an efficient use of funds, not simply that it's a subsidy (time frame needs to be taken into account too).
- home batteries cost more
- homeowners buying batteries are already pretty well off on average
- a large portion of the population (renters) is excluded from the policy.
- prices are falling anyway so the subsidy is just a waste of tax dollars, arguably
- grid scale batteries are more cost effective and benefit everyone via cheap prices broadly, instead of specific homeowners.
Etc. but pork barreling be pork barreling.
Meanwhile the government doesn't have any of its own money, so it can't really give you something that was yours to begin with, all it can do is take it from you and then give it back with strings attached. How is that helping you? Instead of subsidizing something you can make up your own mind about whether you want, they should just lower your taxes by the amount of the subsidy and let you use your money for that or something else at your choice.
Spoken as someone who never been poor. There is definitely a ton of stuff people with money can do to save more money, that is completely out of reach for the people who would actually benefit from those savings the most. Subsidies is quite literally about reaching these folks that others tend to forget about.
> all it can do is take it from you and then give it back with strings attached. How is that helping you?
Compared to "take it from you and not give it back to you", it's definitely helping people who have less money. Not sure how this needs explaining.
Except that there is no additional money, its just your own money but now there are strings.
On top of that, that still isn't necessary for things that save a non-trivial amount of money, because that's what loans are for. If it has a $100/mo loan payment and saves $150/mo on the electric bill then you take out a loan or buy it on an installment plan and don't need to have any accumulated capital in order to do it.
> Compared to "take it from you and not give it back to you", it's definitely helping people who have less money. Not sure how this needs explaining.
Why would anybody want that either, instead of just not taking it from you to begin with?
Upthread: "interest free loan of 15k" https://news.ycombinator.com/item?id=48904009
>>> If it has a $100/mo loan payment and saves $150/mo on the electric bill then you take out a loan or buy it on an installment plan and don't need to have any accumulated capital in order to do it.
This depends on whether you'll pay back the loan. Just because paying the loan back saves you $50 / month forever starting immediately doesn't mean you'll do it. You might be the kind of person who takes out a loan, spends all your money on something else, and lets the bills go unpaid.
If you aren't that kind of person, you probably do have some accumulated capital.
But if you are, just the fact that the loan is hugely profitable and you should be able to pay it back - if you were a completely different person - doesn't mean you'll be able to get the loan. You shouldn't be able to get the loan, because you won't pay it back.
And there's your grift. As soon as the home owner wants to allocate the "profit" of install to themselves, it is a swift kick in the ass but that will go to our buddies, and thank you very much for your taxes.
[] https://www.energy.nsw.gov.au/households/grants-rebates/home...
I understand what you mean, and yeah, "it's just your money", but also, it really isn't. Poor people have to pay taxes, no way around it, getting them back as subsidies is still better for them than not getting it back at all. The choice isn't "Keep the money or have subsidies", the choice is "The money goes to other stuff or get subsidies".
> On top of that, that still isn't necessary for things that save a non-trivial amount of money, because that's what loans are for. If it has a $100/mo loan payment and saves $150/mo on the electric bill then you take out a loan or buy it on an installment plan and don't need to have any accumulated capital in order to do it.
Are those interest-free or managed by for-profit entities? Because "loans" are vastly different things compared to subsidies, but I'm guessing you already knew this.
> Why would anybody want that either, instead of just not taking it from you to begin with?
Because "not taking it from you to begin with" isn't a practical and realistic alternative, that's not how the world, and especially taxes and government works...
That's the false dichotomy that happens in a broken government, but then why hold that out as something desirable?
> Are those interest-free or managed by for-profit entities?
Is the larger amount of mortgage or car loan debt they have to carry when they pay the extra money in tax?
> Because "not taking it from you to begin with" isn't a practical and realistic alternative, that's not how the world, and especially taxes and government works...
Your argument seems to be that lowering taxes on ordinary people is impossible?
Personally I see it as stuff that happens in countries where the government care about the well-being of all, not just a select few (usually the ones with the most money). It's desirable that society improves, lots of that happens because of tax money. Subsidies usually means re-allocating funds, not raising taxes, although that might happen over time. Still, increasing taxes isn't inherently bad, especially when used for good. But I also know this is a somewhat controversial point of view in many hyper-capitalistic societies.
> Your argument seems to be that lowering taxes on ordinary people is impossible?
Yeah sure, I'm also clearly arguing for murdering children. Fun discussion, hope you'll enjoy the rest of your Tuesday :)
I don't think that's entirely unreasonable. After all there are hardly any personal incentives for individuals to invest into infrastructure, education or healthcare of people who can't afford it and plenty of other areas even if that's what allowed them to accumulate a significant proportion of not the overwhelming majority of their wealth over the long term.
Given that most taxation done with the the advertised goal of helping the poor in Australia does happen with popular assent of individuals, I would theorize your position is false and that people do have some individual incentives to develop services offered to the poor -- for profit, humanitarian / charitable reasons, and a variety of other considerations.
I never said that wasn't the case but historically that "some" was never sufficient. On average people are rational and selfish to a larger extent than they are altruistic.
> taxes in that pursuit are illegitimate under a theory taxation happens by the assent of the people
Well the whole concept of an organized society falls apart if individuals can personally freely chose which laws to obey and which taxes to pay. You have to have a balance based on a reasonable consensus, otherwise you end up with totalitarianism or anarchy (and in that case the people who have the means and resources to do that will establish alternative power structures and will end up subjugating those who do not AND also outcompete those how have the means but are unwilling to do the same).
It can't simultaneously be true that most don't want to help the poor at their own cost while also the tax has been legitimized by the majority wanting to help the poor at their own cost. Only individuals or representatives elected by individuals can vote and if their incentive was to not help the poor then they'd vote not to and that would be that.
Or people have a tendence to perceive a system where everyone is required to pay their "fair share" as more just and are more willing to (often begrudgingly) participate in it. If the system was fully voluntary the average contribution would be significantly lower that it is now. Also a significant proportion might feel they benefit from this system more than they pay into it (or are risk averse and prefer having the safety net even if they contribute more than they benefit)
> decided they individually are incentivized to help the poor develop infrastructure
Well I'm generally vaguely incentivized to help the poor and develop infrastructure. Would I be willing to voluntary give up 40% of my income to do that rather than a significantly lower proportion? No, of course not. When it comes to infrastructure I'd be willing to pay very little or nothing at all if I know my neighbour isn't contributing anything. I don't think the average person would behave particularly differently than me.
It's actually quite rare to find someone who says I will help the poor, but only if my neighbor also pays, otherwise they can get fucked. This is very bizarre thinking. The people in my basically ancap-dystopia neighborhood don't even behave in this sadistic way. It honestly sounds more like a manufactured "gotcha" to win an argument than a way someone would think.
In reality the fraction people that would vote to tax themselves, are more than willing to donate in the case they don't get the tax, your sadistic MAD view where you punish the poor just because some other guy didn't help too is relatively rare and not indicative of the mindset of most people who are voting to help the poor. I honestly think that most anyone who would vote for the tax, does not act that way when dropped in a neighborhood like mine, and you probably would not either.
When you get money, you can choose to spend it on what's worth the most to you. Thus "strings attached" on the opposite.
…assuming people are good at math.
And given that most people probably don't have a bunch of cash just sitting there doing nothing, they will have to take out a loan and most folks probably don't like going into debt even though 'the math says' it's a good ROI.
The idea that 'ROI good, therefore people will do it' is the 'spherical cow' of economics. In reality there are all sorts of other motivations for human economic actions:
It looks more like to me some installers saw their industry was becoming commoditized and the government got together with them to figure out how to grift taxpayers into making the more connected ones command a premium while simultaneously being better positioned to eat the lunch of the small middle class "guy and a truck" who does cash jobs for cheap but has no resources to become "accredited" on a subsidization list.
E.g., if the marginal cost of supporting 1 kW of new capacity may be X, while the current averaged cost of 1 kW provided to existing customers may be Y, with Y < X.
The customer will calculate their ROI on a battery purchase based on the cost Y of kW to them, which may be poor (4%), while on the government level of the ROI may is closer to that implied by the cost X (say 10%). However, the government cannot easily pass on the "marginal cost" to customers as there is no specific kWh which is that marginal one across all customers.
In this case a subsidy directly picks out customers who can reduce their demand by buying a battery (e.g., a subsidy which raises the ROI to somewhere between 4% and 10%).
This is what loans and installment plans are for, the payments for which come out of the savings on the utility bill.
> It's beneficial for society here if the government redistributes wealth for the benefit of all.
Which has nothing to do with batteries. If you want to do that then provide them with a refundable tax credit that allows for a negative tax rate in cases where that's deemed desirable.
And even that doesn't apply to the majority of people who are currently paying a non-negative amount of tax. Why attach strings to the money going to a middle class homeowner who should have just been allowed to keep that portion of their own salary?
Neither loans nor subsidies are dirty words IMHO.
But that's the point. It isn't. Electricity costs more in the evening than during the day and there is a technology that can profitably be used to arbitrage the difference. There is no coordination problem at all, people have the direct individual incentive to buy the technology, on credit if necessary, without any form of government subsidy or involvement whatsoever.
Yet people frequently don't. This assertion and reality disagree.
The money saved is distributed across the community, for both those that directly benefit and those that can't (eg renters, apartments etc). The general benefit is of greater value than the individual savings.
Your attitude that somehow taxation is theft is a very silly Ayn Randian Objectivism outgrowth that has never been true, even in the most "free" US states.
Only if the utility company is pricing things incorrectly.
If the price of electricity is ~free during the day and expensive in the evening then the individualized incentives for installing a battery line right up.
> Your attitude that somehow taxation is theft is a very silly Ayn Randian Objectivism outgrowth that has never been true, even in the most "free" US states.
Whether it's theft or not doesn't change the arithmetic. When you're paying them the money they're paying you, it was your money to begin with.
So the thing everyone correctly maligns because it's generally some form of corruption or inefficiency?
I think the likely cost would have been hundreds of billions considering Australia does not have a nuclear energy generation industry. It currently has a very small nuclear workforce as it only has a small nuclear medical reactor on the outskirts of Sydney.
It's just a treasonous level of corruption.
Voters opting to be extorted like this would have been stupid.
$15 billion is far more than Snowy 2.0 should have cost. But it remains substantially cheaper than any lithium-ion battery build for bulk storage. Storage on this scale is essential in a post-coal electricity grid, and batteries are not (yet) plausible substitutes for bulk storage.
[0] This assumes linear scaling. In reality, placing an order like this would grossly distort supply and demand on many levels. Thus the cost would ultimately be superlinear.
And the comparison shouldn't be to batteries alone, but solar/wind and batteries. The former can be used directly and fill the batteries repeatedly on a timeline that is predictable.
It provides no extra value for the electricity to be stored long term if for the same money you can generate and store it short term.
Article on the various restrictions on Snowy 2.0:
https://theconversation.com/snowy-2-0-cost-blowouts-might-be...
The cost of the Snowy 2.0 pumped-hydro project is estimated to range from \(\$12\) billion to as high as \(\$42\) billion depending on the scope of costs included (such as direct construction, interest, and broader transmission). Originally announced in 2017 with a $2 billion price tag, the project has faced massive scale and logistical blowouts. The cost of the Snowy 2.0 pumped-hydro project is estimated to range from $12 billion to as high as $42 billion depending on the scope of costs included (such as direct construction, interest, and broader transmission).
That said , hydro systems have a LONG LIFESPAN - 100 YEARS ?
Batteries need to be replaced every X years.
So the ecomiomics of the comparisoan would need to be calculated ...
One of the scariest industrial deaths you can imagine: cutting into a pocket of shale and the TBM and crew just vanishing into the maw of the Midgard serpent and the whole tunnel filling.
https://www.abc.net.au/news/2024-05-22/tunnel-boring-machine...
[1] https://en.wikipedia.org/wiki/Dinorwig_Power_Station
[2] https://www.waterpowermagazine.com/analysis/re-planting-the-...
It didn't work at all for that though - we had a lot of private investment in large-scale batteries anyway, because the cost came down quickly just as most people (apart from the conservatives) expected. Then the other side of Government got in and put a subsidy scheme to get hundreds of thousands of home batteries installed, which has been multiple times better bang-for-buck than the Snowy 2.0 scheme, as well as taking far shorter a time. At the same time coal plants are shutting down as expected because they are increasingly unreliable given their old ages.
Snowy 2.0 be an expensive stranded asset basically, it will work and be somewhat useful but extremely uneconomical so basically relying on the cost being written off - if it had to recoup any investment then it couldn't run because it'd never be able to sell the power for high enough.
And you can get out every drop. And it’s always ready to go. Do need to cycle your inventory.
Fire departments probably wouldn’t be happy about it.
(did you mean 20kwh per user, or 20GW overall?)