In Australia, a home battery boom has helped cut wholesale power prices • Hacker News Board

Re: In Australia, a home battery boom has helped cut wholesale power prices

#281

Post by throwaway2037 » Sat, Aug 15, 2026, 4:01 AM UTC

dhx wrote: post #144

m101 wrote: post #111

Is the only reason that a behind the meter subsidy is more efficient because it reduces the upfront for an equivalent kWh storage (with the consumer footing the difference)? I would have thought few, larger, batteries at local substations was more efficient otherwise.

Distribution infrastructure capacity is a current and ongoing concern for summer peak loads (every house turning on air conditioners at once) even with the large government subsidies that have existed for residential solar panels, residential batteries, reverse cycle heat pump cooling/heating and insulation. The cost to rebuild every distribution substation, change every pole-top transformer and rewire suburbs would…

    > As a side note, perhaps Australia perhaps has the most open and transparent electricity market in the world?

I did some light research. I would mostly agree. Other honorable mentions: The Nordic Pool, Europe, Great Britain. They are all excellent.

How do you know so much about the Australian power grid? Is it a hobby (personal interest) or profession-related?

Re: In Australia, a home battery boom has helped cut wholesale power prices

#282

Post by throwaway2037 » Sat, Aug 15, 2026, 4:05 AM UTC

skissane wrote: post #248

tialaramex wrote: post #151

Earlier quoted context omitted.

As you say, Australia is very big. Big sections of it are also, as a result, empty. The coast-to-coast "long distance transmission" is not in fact a thing in Australia. China has long distance HV transmission, but it's crazy expensive and they built it because most of China's people live near its coast but most of its solar power is in the interior so the power needs to be moved. Australia is exceptional for having a…

> The coast-to-coast "long distance transmission" is not in fact a thing in Australia. The main Australian electricity grid reaches from Cooktown in far northern QLD [0] through to the Lower Eyre peninsula in South Australia [1] and down to the Huon Valley in Southern Tasmania [2]. So if by "coast-to-coast" you mean "East Coast" to "South Coast", then literally we have it already. Of course, I take it you actually me…

Speaking of insanely good solar power potential in large parts of Australia: I am surprised that we have not seen huge solar farms setup to power aluminium smelters. I guess that the economics still doesn't work. As I understand, all the cheapest places use hydroelectic as their power source.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#283

Post by throwaway2037 » Sat, Aug 15, 2026, 4:09 AM UTC

testing22321 wrote: post #30

I put 7.3kw of panels on our roof for $0 of our money thanks to a $5k rebate and $8k interest free loan. It makes 7.2Mwh of power a calendar year, which would cost $1000 if we had to pay for it. So for 8 years we pay the loan instead of for the power, then we get -25 years of $1000 a year in our pockets. The price of power is also pre approved to increase a minimum of 5% a year every year here, so the savings will be…

I think it would be less click-baity to re-write your first sentence as:

"I put 7.3kw of panels on our roof for a $8k interest free loan and a $5k rebate."

    > The price of power is also pre approved to increase a minimum of 5% a year every year here, so the savings will be more than that.

That 5% growth rate sounds economically unsustainable. Power prices in rich, highly-developed countries in the last 50 years surely have grown much slower than 5% per year.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#284

Post by skissane » Sat, Aug 15, 2026, 4:18 AM UTC

stubish wrote: post #262

skissane wrote: post #238

Earlier quoted context omitted.

> Residential demand is only down by 6% and part of that is likely due to the effective ban on gas in new residential construction which started in 2023 in Victoria. Prior to 2023 residential gas usage was increasing. There's a lot of people who would get gas if only it were available. My house (in NSW), the gas main ends two streets away, they won't connect me unless I paid them some insane amount of money ($100K or…

With gas getting more and more expensive here in Victoria, and electricity prices plummeting and already free if you get a decent sized battery, the gas connection ban seems mostly pointless. Nobody will pay $300/year for the connection (+installation) so they can have the privilege of paying for their heating and cooking, and even without a battery you are still looking at 3-4 times the cost with gas heating vs. ele…

A lot of people still prefer gas stoves for cooking

Yes you can get bottled LPG gas, but it is a pain – you worry about running out, you have to call up and get them to deliver it. With piped gas you just set up a direct debit for the bill and never think about it ever again.

Also, some people prefer gas heaters because it is a different kind of heat. My father replaced his wood combustion heater with a gas one, even though he already had reverse cycle air-conditioning. Maybe just using the air conditioner would have been cheaper (he already has rooftop solar–I don't think he has a battery, but could easily put one in), but it wasn't what he wanted.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#285

Post by stubish » Sat, Aug 15, 2026, 4:23 AM UTC

Wacari wrote: post #9

so in other words, heavily subsidize another technology (introducing cost shifts onto non-adopters, typically poorer people) to try and solve operational problems directly caused by oversubsidizing rooftop solar (another regressive cost-shift and extremely inefficient cost allocation relative to tx-connected solar) by bringing down wholesale prices (already a minority of the utility bill). Fixed costs, the majority o…

In Victoria, today, you could get a $10,000 loan, install a battery in your apartment, and switch to a free power or VPP plan costing just $0.30/day after kickbacks, and have it all pay for itself in 5-10 years. The people being left behind are renters, so some incentive there still needed to get landlords on board. Or legalize and subsidize the wallsocket plugin batteries now on the market so renters can make their own investment.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#286

Post by defrost » Sat, Aug 15, 2026, 4:30 AM UTC

throwaway2037 wrote: post #282

skissane wrote: post #248

Earlier quoted context omitted.

> The coast-to-coast "long distance transmission" is not in fact a thing in Australia. The main Australian electricity grid reaches from Cooktown in far northern QLD [0] through to the Lower Eyre peninsula in South Australia [1] and down to the Huon Valley in Southern Tasmania [2]. So if by "coast-to-coast" you mean "East Coast" to "South Coast", then literally we have it already. Of course, I take it you actually me…

Speaking of insanely good solar power potential in large parts of Australia: I am surprised that we have not seen huge solar farms setup to power aluminium smelters. I guess that the economics still doesn't work. As I understand, all the cheapest places use hydroelectic as their power source.

Nyrstar Port Pirie isn't 100% renewable, it should be now be recovering blast furnace heat as electricity to reduce demand and that demand is partly met by South Australia's renewable generation which covers the non industrial demand with excess left over for some industry.

That aside (I'd be interested in further detail there) Rio Tinto is asserting the the largest aluminium smelter in Australia ( Tomago smelter near Newcastle ) will be 100% renewable energy within the decade:

Australia’s largest aluminium smelter to run on renewables by 2033 after Rio Tinto strikes $2.5bn taxpayer bailout deal - https://www.theguardian.com/business/2026/aug/13/rio-tinto-a...

Rio can be a bit performative in it's claims though; its battery electric haul pak "fleet" is over stated and they didn't do nearly as well at not blasting protected sites to smithereens as they pinky promised they would.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#287

Post by lazide » Sat, Aug 15, 2026, 4:37 AM UTC

sarchertech wrote: post #241

lazide wrote: post #217

Earlier quoted context omitted.

Uh, why do you think the Fed injects funds the way it does?

Sure that’s one of the argument for why they do it but the money doesn’t directly to most small businesses, we do have small downturns, and they don’t result in the majority of small businesses going out of business.

have you seen the turnover stats on small businesses? most ‘die’ in a few years anyway.

look up the history of why the fed exists and you’ll see why we have ‘small’ downturns.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#288

Post by stubish » Sat, Aug 15, 2026, 5:03 AM UTC

skissane wrote: post #284

stubish wrote: post #262

Earlier quoted context omitted.

With gas getting more and more expensive here in Victoria, and electricity prices plummeting and already free if you get a decent sized battery, the gas connection ban seems mostly pointless. Nobody will pay $300/year for the connection (+installation) so they can have the privilege of paying for their heating and cooking, and even without a battery you are still looking at 3-4 times the cost with gas heating vs. ele…

A lot of people still prefer gas stoves for cooking Yes you can get bottled LPG gas, but it is a pain – you worry about running out, you have to call up and get them to deliver it. With piped gas you just set up a direct debit for the bill and never think about it ever again. Also, some people prefer gas heaters because it is a different kind of heat. My father replaced his wood combustion heater with a gas one, even…

Key words here are 'some people' and 'prefer'. I think this causes prices to spiral up (but this might be papered over by government subsidies). Do you prefer gas enough to pay $300/year for the connection fee? Or will you take the less-preferred but economically more palatable option and disconnect? And everyone who disconnects drives the prices higher for the fewer holdouts. Until retailers and suppliers pull the plug because there is no profit in it, and most people won't support bail out subsidies for the some people.

For your father's gas heating, this really sounds like an emotional decision. Modern gas heating produces the same heating as reverse cycle, where air is passed over a hot bit of metal and expelled into the room. One bit of metal is heated by an enclosed and externally ventilated flame and the other bit of metal is heated by a heat pump, but the interior side is practically the same. He might be paying hundreds or thousands of dollars a year because the fan in the gas heater happens to blow the hot air more where he wanted it or more where he was used to it.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#289

Post by testing22321 » Sat, Aug 15, 2026, 5:03 AM UTC

throwaway2037 wrote: post #283

testing22321 wrote: post #30

I put 7.3kw of panels on our roof for $0 of our money thanks to a $5k rebate and $8k interest free loan. It makes 7.2Mwh of power a calendar year, which would cost $1000 if we had to pay for it. So for 8 years we pay the loan instead of for the power, then we get -25 years of $1000 a year in our pockets. The price of power is also pre approved to increase a minimum of 5% a year every year here, so the savings will be…

I think it would be less click-baity to re-write your first sentence as: "I put 7.3kw of panels on our roof for a $8k interest free loan and a $5k rebate." > The price of power is also pre approved to increase a minimum of 5% a year every year here, so the savings will be more than that. That 5% growth rate sounds economically unsustainable. Power prices in rich, highly-developed countries in the last 50 years surely…

Our local power utility has realized they’re waaay behind on maintenance. This year power went up 7% in town and 16% for those out of town.

Both going up 8% next year.

Re: In Australia, a home battery boom has helped cut wholesale power prices

#290

Post by jiehong » Sat, Aug 15, 2026, 6:14 AM UTC

wolvoleo wrote: post #231

AnotherGoodName wrote: post #17

It started with a solar boom, many small home scale solar roofs popping up everywhere. Australia has a free trade agreement with much of the world, including China, and solar panels have literally dropped to 1/50th of the price they were in 1990 ($10/W to $0.2/W today). A shout out to the work that was done to establish dynamic grid pricing too. Anyway that caused power prices to reliably go negative during the day a…

Free Trade is amazing when it works. But it doesn't in many cases. Even with those solar panels: China has put many western manufacturers out of business by selling them under cost price with government support. It's cool for the consumer but it's an artificial trick that actually reduces the free market viability. They did this with a reason. Either to raise prices later or to create a dependency. Even if you don't…

Solar panels and batteries aren’t something you use up daily and have to buy constantly.

So, if by creating a dependency you mean they hope you buy again in 20 years, sure, but it’s not petrol style dependency, and those batteries and panels can be recycled locally instead of sent back to China.