Suburban wind power generation practical?

Forums › Home Workshop DIY › Suburban wind power generation practical?

1 | 2 | 3 | 4 | 5

441 posts

Ultimate Geek
+1 received by user: 289

#3381585 7-Jun-2025 15:49

The segment of society that finds it troubling (mostly engineers) call wind & solar 'unreliables'...

As Spain & Portugal just found out, it's challenging to keep a grid reliable when it drops below a preponderance of power generation with rotational inertia.

And wind & solar don't have it.

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3381588 7-Jun-2025 16:18

variable power sources need storage for them to work well. in fact thats whats happening here and around the world, lots of power storage is being installed. we have one up here in ruakaka and there is a big one planned for huntly.

pdh

441 posts

Ultimate Geek
+1 received by user: 289

#3381613 7-Jun-2025 18:07

>...here and around the world, lots of power storage is being installed.

Umm, well not really.

That's a popular narrative - but you need to be arithmetically challenged to believe it.
Projects are being done - but at tiny scale and enormous cost.
Humanity doesn't have enough money to build sufficient battery or pumped storage for anything but spikes & surges.

Right now, on a not-too-cold Saturday afternoon in June, Auckland is using 1000 MW.
I believe we can peak at about 5 times that.
So a battery for Auckland (right now) would need to be rated 1000 MW.
And to keep us going for an hour, it would need a capacity of 1000 MWh (mega-Watt-hours).
To keep us going for two hours... a capacity of 2000 MWh, and so on.

Australia is building one of the biggest battery storage parks in the world - the Waratah Super Battery.
It's going to have a capacity of 1400 MWh - so 84 minutes for Auckland.

If we needed it on a cold winter night - at our peak load - it would keep us going for 17 minutes.

And it's costing 1 to 2 billion $A (hard to get an accurate figure, because it's politically embarrassing).

So... to keep Auckland running over an extended period of cloudy/dark & no-wind/still conditions (ie: German 'Dunkelflaute')...
Let's say 2 days at 1000 MW - that's about 35 Waratahs - or about 100,000 $NZ dollars for every family in Auckland.
Need that in mid-winter and/or throw in a few more BEV's and it'll cost you x5.
And those batteries don't last forever.

Perplexity tells me that 2024 World Installation of Grid-Scale Battery Storage was 160,000 MWh - 65% in China.
Yes, that's 100 Waratahs - and up y-o-y by 50% - but it's still only going to keep China running for 7 minutes.

Don't trust me - or, of course, anyone on the internet - but please run some numbers for yourself !
And cogitate on why all the AI boys & girls are suddenly polishing the tarnish off Nuclear...

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3381648 7-Jun-2025 19:04

i wasn't suggesting they are a giant ups, but rather to smooth out the peaks and throughs of solar/wind. this makes it easier for the hydro/thermal/etc to control their supply. so when the sun goes behind a cloud your lights don't go dim etc. soak up any oversupply and supply when demand peaks.

Yoban

453 posts

Ultimate Geek
+1 received by user: 86

#3381658 7-Jun-2025 20:20

This as a solution https://thearchimedes.com

kiwifidget

"Cookie"
3640 posts

Uber Geek
+1 received by user: 1969

Lifetime subscriber

#3381662 7-Jun-2025 20:27

Yoban:

This as a solution https://thearchimedes.com

and what happens when you blow in to a seashell? 🤪

Delete cookies?! Are you insane?!

Dyson

Shop now for Dyson appliances (affiliate link).

timmmay

20858 posts

Uber Geek
+1 received by user: 5350

Trusted

Lifetime subscriber

#3381697 8-Jun-2025 08:43

Yoban:

This as a solution https://thearchimedes.com

Interesting, thanks. The larger 1.5m diameter one can produce around 500W, so to get a useful amount of power you'd need 4-6 of them, which seems impractical.

RunningMan

9184 posts

Uber Geek
+1 received by user: 4834

#3381701 8-Jun-2025 09:06

Wow, they don't even know the difference between Wh and W. https://thearchimedes.com/products

The AWM comes in two sizes:
The 1.5 meter diameter with a rated power of 700 Wh and a maximum of 1 Kwh and the 0.75 meter diameter with a rated power of 125 Wh and a maximum of 150 Wh.

Not excusable when that is your primary product for sale.

mudguard

2327 posts

Uber Geek
+1 received by user: 1250

#3381702 8-Jun-2025 09:12

I've thought about this a little. We are on mains gas and and live on a bit of a hill where it's almost perpetually windy. The only issue I have with solar is we have faux terracotta roof tiles (concrete I assume) and a few others have solar and the black rectangles are quite jarring.

Whereas a single vertical turbine on top of the roof would be quite discreet. And if all it did was heat a hot water cylinder it may make a useful difference.

mudguard

2327 posts

Uber Geek
+1 received by user: 1250

#3381704 8-Jun-2025 09:18

pdh:

Let's say 2 days at 1000 MW - that's about 35 Waratahs - or about 100,000 $NZ dollars for every family in Auckland.
Need that in mid-winter and/or throw in a few more BEV's and it'll cost you x5.
And those batteries don't last forever.

Perplexity tells me that 2024 World Installation of Grid-Scale Battery Storage was 160,000 MWh - 65% in China.
Yes, that's 100 Waratahs - and up y-o-y by 50% - but it's still only going to keep China running for 7 minutes.

Don't trust me - or, of course, anyone on the internet - but please run some numbers for yourself !
And cogitate on why all the AI boys & girls are suddenly polishing the tarnish off Nuclear...

I veiw it a little bit like water though. In Auckland it seems ludicrous that water storage isn't mandatory for housing. We get so much water during winter that it would a decent difference if each household hung onto some of it.

I think of electricity a bit the same way. If every home had solar, wind and storage, what would that do to demand?

tweake

2641 posts

Uber Geek
+1 received by user: 1137

#3381717 8-Jun-2025 10:21

mudguard:

I veiw it a little bit like water though. In Auckland it seems ludicrous that water storage isn't mandatory for housing. We get so much water during winter that it would a decent difference if each household hung onto some of it.

I think of electricity a bit the same way. If every home had solar, wind and storage, what would that do to demand?

water of course has hygine requirements and the whole point of town supply is to ensure everyone has clean healthy water supply. however you need enough people on it to make it economic. a local town here banned tanks in town (many old houses still had tanks) to get more people on it so they could afford to run the system (and then found the system could not keep up and ask people to put tanks back in).

with power you also need enough people on the system to pay for the system. the good thing is theres plenty of people on the power grid, so even if every house had solar, the system will still earn enough to pay for itself. it also means companies won't have to expand as quickly as the population grows.

in places like usa they spend huge amount on improving homes efficiencies and industrial power usage, there is huge rebate provided by power companies (as well as state etc), because reducing the demand means they don't have to spend huge amounts to rapidly upgrade the grid.

Dyson

Shop now for Dyson appliances (affiliate link).

morrisk

367 posts

Ultimate Geek
+1 received by user: 161

Lifetime subscriber

#3381740 8-Jun-2025 14:52

I found this video gives a good overview of wind power generation - UK based but still sets out the basic issues.

https://www.youtube.com/watch?v=HW4iyMnblZ8

pdh

441 posts

Ultimate Geek
+1 received by user: 289

#3381777 8-Jun-2025 16:38

>I think of electricity a bit the same way. If every home had solar, wind and storage, what would that do to demand?

I believe that this is a very common point of view.
And you need to think it through - to see the problem.

Our civilisation is built around expecting energy reliability.
We schedule school, work meetings, meals, transport - expecting electricity to facilitate this.
In a looser way of life, we might accept that we could only do stuff when the sun shines.
We'd accept being really cold on windless nights.

So - the more solar we have, the less value conventional power stations have to sell for many (sunny) days of the year.
But we insist that 'they' provide us power in a Dunkelflaute - and they must supply us all - and all the power we might ask for. To be available, they have to maintain a full-size & very reliable 'backstop' power supply & grid. Machinery, people, maintenance, etc. All sitting there - waiting to be needed.

But we only want to pay them for power on the bad days...

See the economic problem with this scenario ?
The closer we get to a full-scale wind & solar power grid - the closer we get to double the cost of Electricity.
Ask England and Germany about this...

Until we crack the problem of excess solar/wind power storage - this is the Achilles heel of unreliables.
And an economic solution is not Lithium, nor pumped hydro, indeed is not yet known.

SomeoneSomewhere

1882 posts

Uber Geek
+1 received by user: 1086

Lifetime subscriber

#3381791 8-Jun-2025 18:35

There's a lot that could be done with demand response (particularly hot water, a bit of space pre-heating/pre-cooling, and EV charging) before we get to the 'shed load' stage. Ripple relays are going out of fashion for no good reason; lines companies have no incentive to fix a generation problem.

Remember that NZ has around a gigawatt of geothermal base load, plus a fair bit of run-of-river hydro and minimum expected wind. We are not expecting batteries to handle the entire grid being turned off for 48 hours.

Spreading batteries out residentially doesn't make it any cheaper than doing it centrally. Likewise with wind generation. Solar is somewhat comparable because you generally don't need to buy the land or build as much structure.

IIRC the small couple-of-kW turbines weren't really economically competitive with solar when that one in Tawa was installed 20 years ago - one went up at Inglewood High School about the same time; would be interesting to see their stats.

Handle9

11924 posts

Uber Geek
+1 received by user: 9675

Trusted

Lifetime subscriber

#3381794 8-Jun-2025 19:23

tweake:

in places like usa they spend huge amount on improving homes efficiencies and industrial power usage, there is huge rebate provided by power companies (as well as state etc), because reducing the demand means they don't have to spend huge amounts to rapidly upgrade the grid.

New Zealand has done much the same though EECA and insulation/heat pump subsidies. The schemes are a little different but much the same net effect. In addition decarbonisation subsidies are generally energy efficiency projects.

As energy prices increase they become less necessary as the business case becomes more and more attractive. A lot of companies stopped applying for subsidies as the technology was demonstrated and had attractive ROIs. The biggest one I was involved with in New Zealand had a cost in the millions with simple payback of less than 5 years.

1 | 2 | 3 | 4 | 5