Hacker News Reader

Comment by llm_trw | Hacker News Reader

I worked as a quant in energy for the Australian market.

I did the same thing as OP but didn't assume electricity teleported 3,000 km from Tasmania to Northern Queensland.

Using the proprietary data for what each pole could carry I build a first principles simulation of the Australian grid to find where medium sized battery installations should be placed to provide maximum grid frequency correction.

The grid is already close to collapse on 40C days.

Forget moving to a renewable grid, keeping the lights on during a five day heat wave over the eastern seaboard is currently impossible.

View on HN

At moments like this it is important to remember that models are notoriously wrong. The take away for me is that we're getting to the threshold where solar is genuinely an economic option and if the price of solar energy keeps coming down it'll probably be the energy source of choice in Australia.

The article talking about 'replacing' is a bit weird, that doesn't make any intuitive sense. We'd keep the existing generation infrastructure then start augmenting it with cheap renewables.

Solar is stupidly cheap. I'm building a 40kw hybrid system with 50kwh of storage for less than 20k USD in Thailand. It's this cheap because there is 0% duty on my solar panels and inverters, I was able to source locally made aluminium racking. Of Course that is a DIY price, commercial installation would have been a lot more. However there was still 30% duty on the batteries that doesn't need to be there IMO.

Australia should negotiate a deal with China, remove all import tariffs on green energy products in exchange for guarantees of local manufacturing being setup here within 5 years and then subsidize the shit out of everyone doing rooftop solar with storage. If you remove the tariffs on LFP you can easily get down to $100USD/kwh for storage and similarly for panels $125USD/kw for rated power.

If everyone is running rooftop solar w/storage and not doing any export (or minimal export) the grid impact is purely positive and doesn't require smart grid shit to regulate things. It's possible to add an absolutely massive amount of capacity this way cheaply, without tech or solutions that don't exist yet and without much political capital being burnt other an upsetting some butthurt Americans that you are doing business with China.

What's the net metering situation in Thailand. I assume not that good if you decided to get storage. Did you get a lifepo4 battery?

There is net metering but it has two major problems.

1) It's hard to get approved, doubly hard for a DIY installed system, even if I could jump through the hoops (eletrical engineers drawing etc) there is also a quota so there isn't a gaurantee it would be approved.

2) The rate isn't that great, it's about 30% of retail.

However all of that is moot in my case because my power needs exceed that of the available utility power at my location.

So I essentially have a 3 phase completely off grid solar system. So why did I say hybrid? Well that is because I do have a utility supply but it's a 15/45A supply but it's got horrible voltage drop (I'm 2.5km up a mountain from the transformer) and it's 1ph and I need 3ph power for my EV charger, air conditioning and pool pumps.

So what I did was add an AC charger that is configured to charge from grid if the batteries drop below 30% state of charge. So it's essentially a hybrid system, DC coupled to the 48V batteries but really the grid supply is just a backup, the system is specced to operate completely off-grid.

Yes the battery system is LFP, I went for 5 x 48V 200AH server rack mounted packs in parallel.

I'll probably also eventually add a diesel generator so that there is no way I will ever lose power but for now the batteries + grid charger are going to be enough.

Pardon my ignorance, but isn't aircon an easy case for the grid? The same sun that causes the heat can power solar panels, so it doesn't even need storage or long-range transmission.

You are assuming that you don't need an aircon at night. Something that's very much not the case during a multiday Australian heatwave.

Do you have any insulation? I'm in the UK, and my previous rental had walls that leaked any heat within half an hour, but my current one, it heats up to 23 in the day due to the large windows facing the sun, and barely drops to 18 at night when it's 5-10 degrees outside.

>Do you have any insulation?

No, this is Australia. Houses are more like tents than actual buildings.

Tents are sturdier.

> No, this is Australia. Houses are more like tents than actual buildings.

Pre-AC being ubiquitous (or being invented), the way for people to cool off in summer was to have airflow. Insulation was a more of a cold climate thing, as keeping the heat in / cold out was more intuitive when burning wood or coal: thermal boundaries were more 'needed' when there was snow outside.

Having thermal boundaries in your structure didn't make sense when it was as hot inside (due to lack of AC) as it was outside, and it has only been in recent years that people clued into that fact. But unfortunately there's a large stock of housing around that was built pre-clue in.

Even now there are people who insist that houses need to "breathe", i.e., have holes / be drafty. They do not:

* https://www.energyvanguard.com/blog/Myth-A-House-Needs-to-Br...

* https://www.greenbuildingadvisor.com/article/most-houses-tha...

* https://www.greenbuildingadvisor.com/article/buildings-dont-...

Buildings need to be as air tight as possible, and be ventilated through mechanical means so that stale air is vented out and fresh air is brought in after being filtered and tempered (via an ERV).

>> Buildings need to be as air tight as possible

Perhaps in California, Australia or other desert areas. The pacific northwest had major issues when OSB met the concept of "air tight" housing. No airflow in/through walls leads to condensation, mold and collapse of many "engineered" wood products held together with glue.

> The pacific northwest had major issues when OSB met the concept of "air tight" housing. No airflow in/through walls leads to condensation, mold and collapse of many "engineered" wood products held together with glue.

These are not indicators that air tightness is bad, but rather that people don't understand building science. Washington state (for one) has mandated air tightness levels (§R402.4.1.3) and testing (§R402.4.1.2):

* https://sbcc.wa.gov/sites/default/files/2023-04/2021_WSEC_R_...

Air tight passive houses are built without issues in the US PNW:

* https://phnw.org

* https://hammerandhand.com/high-performance/passive-house-bui...

* https://asiri-designs.com/f/how-to-design-an-energy-efficien...

The province of BC is mandating near-passive house levels of air tightness:

* https://www.energyadvisor.pro/airtight-energy-advisor-contac...

* https://energystepcode.ca/how-it-works/

* PDF: https://www.bchousing.org/publications/Illustrated-Guide-Ach...

Build your structure according to how physics works and it will work just as well from the tropics (IECC Zone 1) to the arctic (IECC Zone 8):

* https://buildingscience.com/documents/insights/bsi-001-the-p...

* https://basc.pnnl.gov/images/iecc-climate-zone-map

Air tightness is coming to building codes everywhere, and if you can't make it work then you shouldn't be building because you are incompetent:

* https://www.iccsafe.org/building-safety-journal/bsj-technica...

You massively overestimate how deserted Australia is. Most of the population of Australia lives in the greener areas near the coast, which has a much more moderate climate.

...also I doubt anyone from e.g. Brisbane would need to be told about mold and condensation.

> Pre-AC being ubiquitous (or being invented), the way for people to cool off in summer was to have airflow.

Modern A/C was invented in 1901, and A/C penetration in Australia is not that far behind the US.

But much as in Texas where houses are also made of paper and cardboard, cheap energy has made forcing temps down via AC much simpler (for property developers).

I have a "normal" Melbourne brick veneer home, with decent roof insulation and insulated curtains. It handles the heat well for 1 day but a 2 or 3 day heatwave of 38 degree plus temperatures the bricks heat up in the sun and it gets quite uncomfortable even at night.

outside sun shield like German houses have is the way to go. Any curtains inside does not work very well

Spent some time in Oz in the 90s- trying to sleep at night in my 2nd floor apartment as the heat rolling off the desert met the Brisbane coast without air conditioning remains some of my most unpleasant memories to this day.

Despite a fan pointed right at me I’d awake every morning with a sweat soaked mattresses…

Brisbane is quite pleasant compared to the NQ. Good times.

Source: In brisbane and lived in the north.

Yep, visited Townsville and it was even more hot/humid, I imagine places like Cairns take it up even further but don’t have quite as much hot desert air sweeping in as Brisbane since its more of a peninsula.

How did people in Australia get by before air conditioning?

I'm not saying that to be snarky, I would generally love to know. I live in a moderately cold climate (England) and I often wonder how people here survived through the winter before the comforts of modern technology. And England's not that cold - how the hell did indigenous Canadians do it, for example? Did people just shiver by a fire for months at a time?

EDIT: I didn't think I was being snarky in my original final sentence, but to avoid misunderstandings I've removed it.

The first sentence is a good question, the last sentence is unnecessary snark.

I think there are two main things at play: buildings used to be built differently, and yes, people prefer not to suffer these days.

Old Australian buildings (e.g. "Queenslanders") were often built on poles to let the air circulate underneath, they'd have the roof extend far over windows to stop sunlight (and heat) getting in. Those are not the most enjoyable places to live in, these days people prefer a bit of sunlight during the day, and a constant draft is not pleasant in winter.

And yes, I imagine people just didn't sleep all that well and spent heatwaves sitting around in the coldest spot in the house waiting for it to be over. These days people want to sleep well throughout the year and want to be productive even during heatwaves.

People were also a lot harder back then because life was harder through the entirety of their existence. Obesity was rare, the average level of fitness was much, much higher, and the teens and adults probably showed a bunch of survivorship bias for hardiness because the weakest died during childhood pretty routinely. I suspect environmental conditions that would kill the average diabetic, obese 45 year old today was just a normal summer day to people back then and was well mostly well tolerated.

I live in Minnesota and have spent a reasonable amount of time winter camping. You use these cool canvas tents and a small, packable wood stove. This has brought me into contact with some folks that live lifestyles somewhat closer to those old days than the new ones - so far as expectations on infrastructure go. For one, they wear warm clothing almost all the time. It’s significantly more efficient to heat yourself (through clothing, food and movement) than heating an entire room/building.

Also: wood stoves large and small can pump out a lot of heat. You can kick up the small tin metal camping stove and make your canvas tent 75 degrees, dry out any wet clothes. Likewise, a large iron stove can make a room boiling. After all, saunas - in one form or another - are a common feature of northern cultures.

Fans and light clothes, mostly.

A lot more people live out in cheaply built homes with small, barren yards and dark roofs that are literally designed for air conditioning. Older homes often have better airflow.

An example of a newer suburb in Sydney is Marsden Park: https://www.youtube.com/watch?v=WzV3H_K73To

I don't use/have aircon in my home in Brisbane and I get by fine :) Although it is nice to have aircon in the summer when I'm working on the computer and need to concentrate (my office at work is air conditioned, like most).

Go to the rural Philippines and you'll find plenty of homes without air conditioning in 40+ heat.

You'll also find westerners accustomed to air-conditioning who live there and have "adjusted".

It takes about 2 weeks and your body makes some sort of adjustment.

It's an interesting phenomenon that maybe someone here can comment on more fully. By that I mean what exactly is happening to us when we adjust? Is it purely psychological or are there actual biological changes/effects at play? Whatever it is you really do "adjust" and it's not that bad after a few weeks. You even learn to sleep well at night in sweltering heat...again after you adjust.

Of course there are limits but we're built to handle the heat.

Heat comes from the sun, but in reality after the sun. Generally speaking, the hottest time of the day (late afternoon) isn't when the sun is brightest (noon). Then people need to sleep, which means they want to be cooler during the evening.

One way to beat the heat is to adjust the workday. Start work at noon. Let people sleep during the cool of morning. But that is a bridge too far for most cultures.

Start at noon? That’s the exact opposite of the approach people take when it’s hot around here (I live in southern Australia where it regularly breaks 40C in summer). Start early - before the sun’s up if you can - and be ready to knock off soon after lunch.

Where I live (French Alps) that's true, because there is a big circadian delta, meaning I can have 30+℃ (86℉) during the day, but at 7pm the temperature is already 25℃ (77℉), at 9pm 20℃ (68℉), at midnight 17℃ (63℉) etc.

But where I was born (northern Italy) the circadian delta is MUCH lower, if it's 35℃ during the day, the night minima is 30℃ at miminum. So you need aircon 24/7, not just during the day.

The grid was much nearer to collapse seven years ago when there were actually brownouts, and renewables have been entirely responsible for its improvement. Moving toward renewables and keeping the lights on in Australia are the same thing.

It's amazing to hear people arguing that the highest electricty prices in the OCED are somehow a sign of a working system: https://www.leadingedgeenergy.com.au/blog/highest-electricit...

Not only does the Australian market have the highest consumer prices it also has the highest number of negative pricing events.

In short: the only reason why the grid hasn't had a brownout since 2019 is because there hasn't been a major heatwave since 2019.

The article you linked is from 2017. 80% of Australia's solar was installed after that came out. Hard to argue that it's somehow responsible. Seems like your knowledge is a bit outdated.

Do you have 40C cloudy days? If not, you don't need to teleport electricity to handle sunny days, you just have to build more local solar generation.

This is what the sky looked like the last time there were more than three days over 40C in a row in Melbourne: https://i.insider.com/5dfc7162e94e8636622f1667

It is also somewhat difficult to use solar power for cooling at midnight when it's still 35C.

It's super easy. Cool to 20C during the day and close your windows. In the morning you should be well under 22C.

I can do the inverse: warm my house to 22C and turn off the furnace overnight when it's -30C. The house won't drop below 20C. And that's a 50C differential. A 14C differential is trivial in comparison.

So you have thousands of dollars worth of insulation because you live in an arctic climate.

Congratulations I suppose.

Now instead of just spending hundreds of billions on building a new grid Australians will also have to spend hundreds of billions on insulating their houses.

To be completely honest, they probably should, and people don't talk enough about proper insulation regardless of the region.

E.g. in colder climates many modern buildings are just hermetically sealed boxes with issues around CO2 levels etc.

For a 14C differential you don't need insulation, you just need to seal leaks.

> For a 14C differential you don't need insulation, you just need to seal leaks.

And hope that your inside air temperature is not at the dew point of the hot, humid air that is outside (thus causing condensation).

If your house had problems with condensation forming on the outside then I hope it never rains where you are.

Water in liquid form (e.g., rain) will (mostly!) go down with gravity, and so overhangs will help a lot, as will proper grade sloping away from your foundations.

Water in vapour form will be more diffuse and be everywhere the air is.

Further, your cladding / water control layer (which deals with rain (and UV)) generally needs to be open to air so that it can dry properly:

* https://en.wikipedia.org/wiki/Rainscreen

so that can lead to moist air getting places that water may not, and if you don't have insulation between the warm-moist outside and the cool-dry inside:

* https://buildingscience.com/documents/insights/bsi-001-the-p...

problems can start.

The picture in my mind was: You have overbuilt solar charging nearby batteries (lithium ion, sodium ion, whatever) to cover the 4-hour busy period at night, and smaller amounts of longer duration storage like pumped hydro to cover the quieter periods after 10pm.

I'm not sure if that'd work out to be cheaper than doing the proposed 60% wind/45% solar mix with inter-state transmission. It would reduce the need for new transmission lines, though.

Aka, really sunny just as suggested.

Cooling at night requires batteries, but their cost is offset by how cheap they are to charge with excess solar resulting in positive feedback loops.

Further, AC needs to work far less hard at night as you avoid solar gain through windows etc, fewer devices are on reducing heat gain, outside temperature drop further reducing heat gain while also increasing AC efficiency.

Or, to echo the main point of the OP: just use gas peakers for these rare events, and when climate deniers try to give you grief for not being 100% pure, wipe your tears with the millions of dollars you've saved by adopting cheap renewables for the other 97% of the time.

I do wonder why there isn't far more solar in Australia already everywhere, given that it's a country of dry deserts and strong sun.

Australia is transitioning >3% of their electricity supply to solar per year and still accelerating. Rooftop solar is near 50% uptake. Combined with wind, they are on track to almost fully in the next 10 years. So there will be soon.

Half the population of Australia (marked in red): https://imgur.com/dA92oJp

Most of the dry desert is irrelevant.

If nobody lives there, it's a perfect place to put some panels.

If you did the same thing as the OP then you'd have some numbers to share, rather than vague fearmongering about grid collapse.

That sounds really interesting. How did you go about creating such a simulation?

Reply on news.ycombinator.com