Power shares

[Snoopy]

Last time I checked, 15,000 x10 = 150,000 = 150MWh

Most Leafs in NZ only have 8-12 KWh of battery capacity remaining, and require a significant amount of this to act as a transport machine

Batteries degrade with cycles, time, usage, temperature

Say a leaf owner charges at $0.15/KWh, sells 5KWh at $0.30/KWh, with energy recovery of 85%, they make $0.63 before tax. Who would bother?

This V2G concept appears to work on paper but will not work in reality

Thanks for checking the maths on my quote from Peter Olorenshaw. It goes with the narrative of architects having great but impractical ideas! It did occur to me that he might have made a mistake in the basis science. But I didn't expect he would trip up on the multiplication!

SNOOPY

[xafalcon]

Thanks for checking the maths on my quote from Peter Olorenshaw. It goes with the narrative of architects having great but impractical ideas! It did occur to me that he might have made a mistake in the basis science. But I didn't expect he would trip up on the multiplication!

SNOOPY

I make home solar energy storage systems using "retired" Nissan Leaf batteries. I obtain the batteries by purchasing a cheap Nissan Leaf with a degraded battery and swap in a good battery from a collision damaged vehicle. The car gets sold with a useful second life, and I get a battery that is perfectly good for home storage for the next 10+ years. By that time I assume battery recycling will be widespread so the cells will have a significant scrap value

So I have a good understanding of the state of NZ's Nissan Leaf fleet, and their batteries

[LaserEyeKiwi]

I make home solar energy storage systems using "retired" Nissan Leaf batteries. I obtain the batteries by purchasing a cheap Nissan Leaf with a degraded battery and swap in a good battery from a collision damaged vehicle. The car gets sold with a useful second life, and I get a battery that is perfectly good for home storage for the next 10+ years. By that time I assume battery recycling will be widespread so the cells will have a significant scrap value

So I have a good understanding of the state of NZ's Nissan Leaf fleet, and their batteries

fantastic - bravo to you good sir. Is this a relatively common thing or are people doing this rather rare in NZ?

[LaserEyeKiwi]

I am not sure it is fair to call Onslow a 'white elephant'. Ciaran Keogh of Environmental Consultants Otago Ltd. thinks there are better solutions. But if we start producing hydrogen fuel in Southland, and Rio Tinto looks to keep the aluminium smelter going down there as well, suddenly we may not have the surplus of power down south that we thought we had. In such a circumstance, having a 'local battery', like Onslow, might be just the thing to have and be in just the right place.

Responding to this article by Dr Kevin E Trenberth

https://www.newsroom.co.nz/kevin-tre...431c1-97981709

Peter Olorenshaw (Architect) has a novel alternative solution based on the number of Nissan Leaf cars already 'installed; in New Zealand.

"And just on batteries - you may be forgetting the batteries we already have here in the form of our Nissan Leafs already set up for Vehicle to Grid operation. They may well be a useful way to store daytime summer solar power and I came across an Australian article. Below is the link to an article on this Vehicle to Grid technology just come to Australia may help out as a grid solar load balancing thing."

https://www.abc.net.au/news/science/...alia/100811130

"While of course we need to reduce our energy consumption and beware of just producing more energy to support our current lifestyles, the thing is that this uses what we’ve already got - these EVs sitting idle for 95% of the time. (And the thing is that Lithium battery chemistries in these EVs seems to be considerably different to other chemistries we may be more familiar with. It appears that the primary degradation in EV batteries is through simple calendar degradation, not number of cycles. In fact Flip. the Fleet found that the more EVs were drive, i.e. the more charges they have, the better condition their batteries were in. So for EV owners if there is no battery longevity downside in using your car battery for grid support and you charge them up at the very low nighttime rates and discharge at very high peak rates, being handsomely rewarded for doing so, why wouldn't you?)"

"The article laments that new EVs will have to be made compatible with V2G applications and that currently only Nissan Leafs and Misubishi Vehicles can do this - But we’ve got some 15,000 used Nissan Leafs here in NZ already, let alone new ones! - the trick is to have them plugged in when we have a solar surplus. Some will be at home during the day, some will be at peoples work places. It would of course need these trick wallboxes wherever the EV is parked most - be that work or home."

"And just how big is that battery capacity available? - if we assumed 10kWh* from 15,000 Nissan Leafs then that is 1,500MWh = about an hour and half of Huntly Power Station going flat out or 3 hours of Benmore station (largest hydro station after Manapouri). In comparison the much celebrated big Tesla grid battery in South Australia (which doesn’t use cars) is 200MWh - so we are talking about 7 times the amount of this celebrated big battery, just from our old Leafs around NZ."

"* The First Nissan Leafs that came out had 24kWh batteries, next model had 30kWh, New shape ones have 40-64kWh so assuming 10kWh from every Leaf is surely not too far out for this back of an envelope calculation."

However, I believe there is flaw in Peter Olorenshaw's calculation. V2G technology was first trumpeted with the second generation Nissan Leaf that started appearing around 2020. So I don't think all of those earlier Nissan Leaf's from 2010 to 2019, which make up the bulk of the NZ Nissan Leaf fleet, have this V2G technology fitted.

https://www.nissan.co.nz/about-nissa...australia.html

Tesla, with the number new vehicles that have appeared on NZ roads since the referenced Newsroom article, may be able to help. Officially Tesla do not promote V2G technology. However, according to this article:

https://electrek.co/2020/05/19/tesla...ging-features/

the hardware does exist within the more recent model 3 and model Y vehicles to make V2G use possible in the future.

SNOOPY

I am pro-Onslow, but in regards to the leaf battery suggestion, Why not just subsidize built for purpose home battery installations instead?

[Snoopy]

I am pro-Onslow, but in regards to the leaf battery suggestion, Why not just subsidize built for purpose home battery installations instead?

Because if you have a battery at home already inside your Nissan Leaf, there is no need to subsidise anything more?

1/ Incremental cost of a pile of Leafs all over the country: $0
2/ Incremental cost of the Lake Onslow 'battery project': $4,000m

So which to choose? Hmmmm?

SNOOPY

[mfd]

Because if you have a battery at home already inside your Nissan Leaf, there is no need to subsidise anything more?

1/ Incremental cost of a pile of Leafs all over the country: $0
2/ Incremental cost of the Lake Onslow 'battery project': $4,000m

So which to choose? Hmmmm?

SNOOPY

The leaf batteries (and any other sensible home battery situation) do nothing for Onslow's primary purpose of being a dry year battery. Last time I did the maths I think you needed to spend something like a trillion dollars putting a couple of hundred Tesla power walls in every house in NZ to match the sheer storage capacity of Onslow. This is not even considering how well they could hold charge over a few months or years.

Could be a good solution to daily balancing of power maybe allowing some extra renewables into the mix (and I believe one of two gentailers are looking at grid scale batteries for this purpose) but this is only an incidental benefit of Onslow as I understand it. The main job is being a big puddle of water to make up for low hydro generation in a dry year, to replace the big pile of coal currently doing the job.

[xafalcon]

fantastic - bravo to you good sir. Is this a relatively common thing or are people doing this rather rare in NZ?

There may be a couple of hundred in NZ

Kiwi ingenuity (number 8 wire) is a dying thing. Apathy, lack of general skills, higher priority use of spare time etc, all contribute to a society that is increasingly reliant on purchasing items rather than making them or repairing them when they break

Our household is entirely electricity self sufficient (saves us $3000pa). We have cheap commuting Nissan Leafs that we charge from our solar (saves us $4000pa). And we sell our excess power back to the grid ($1500pa). System materials cost was $22000 (no cost for my labour). So the maths stack up for those prepared to put in the effort to DIY

[Jantar]

The leaf batteries (and any other sensible home battery situation) do nothing for Onslow's primary purpose of being a dry year battery. Last time I did the maths I think you needed to spend something like a trillion dollars putting a couple of hundred Tesla power walls in every house in NZ to match the sheer storage capacity of Onslow. This is not even considering how well they could hold charge over a few months or years.

Could be a good solution to daily balancing of power maybe allowing some extra renewables into the mix (and I believe one of two gentailers are looking at grid scale batteries for this purpose) but this is only an incidental benefit of Onslow as I understand it. The main job is being a big puddle of water to make up for low hydro generation in a dry year, to replace the big pile of coal currently doing the job.

The primary purpose of Onslow is to allow more intermittent generation like wind power, and to act as a load follower that geothermal cannot do. The dry year risk is a secondary function, but is the one that media appear to concentrate on.

Contact have given up the idea of grid scale batteries for the moment, but may reconsider sometime in the future.

From Energy News

Contact puts battery on ice as prices surge

Steve Rotherham - Thu, 18 Aug 2022
Contact Energy had hoped to have a 100 megawatt battery up and running by late 2024 – about the time its Taranaki Combined Cycle gas plant is decommissioned. But skyrocketing lithium prices have put that on hold, possibly for years.
Managing director Mike Fuge tells Energy News that Contact received preliminary bids from several parties.
“None of them were prepared to take lithium risk, and it just escalated the costs,” he says.
The company isn’t expecting price relief any time soon, says chief financial officer Dorian Devers.
“We suspect that with the length of time it will take new lithium supplies to come to market, it’s going to a while before a new battery is in the money for an investment decision.”

[mfd]

The primary purpose of Onslow is to allow more intermittent generation like wind power, and to act as a load follower that geothermal cannot do. The dry year risk is a secondary function, but is the one that media appear to concentrate on.

Contact have given up the idea of grid scale batteries for the moment, but may reconsider sometime in the future.

From Energy News

Contact puts battery on ice as prices surge

Steve Rotherham - Thu, 18 Aug 2022
Contact Energy had hoped to have a 100 megawatt battery up and running by late 2024 – about the time its Taranaki Combined Cycle gas plant is decommissioned. But skyrocketing lithium prices have put that on hold, possibly for years.
Managing director Mike Fuge tells Energy News that Contact received preliminary bids from several parties.
“None of them were prepared to take lithium risk, and it just escalated the costs,” he says.
The company isn’t expecting price relief any time soon, says chief financial officer Dorian Devers.
“We suspect that with the length of time it will take new lithium supplies to come to market, it’s going to a while before a new battery is in the money for an investment decision.”

Perhaps the primary vs secondary purpose is a little subjective - I was guided by the Government's investigation of Onslow being under the 'NZ battery project' explicitly looking for a solution to the dry year problem which doesn't involve fossil fuels:

https://www.mbie.govt.nz/building-an...my/nz-battery/

However, I'd assume that the main way Onslow would earn money would be through the higher frequency buffering rather than pumping water and sitting on it until a dry year arrives.

I didn't realise Contact had parked their battery plan - Meridian are still looking at batteries as of a couple of weeks ago, "currently tendering for 100 MW/200 MWhcapacity battery". Hopefully they don't reach the same conclusion.

http://nzx-prod-s7fsd7f98s.s3-websit...479/377303.pdf

[Jantar]

Perhaps the primary vs secondary purpose is a little subjective - I was guided by the Government's investigation of Onslow being under the 'NZ battery project' explicitly looking for a solution to the dry year problem which doesn't involve fossil fuels:...

I was involved in the operational modelling for one of the consultants to MBIE. With the dry year backup as the primary focus, there was no way that Onslow could ever be operational, nor financially viable. The only way it could work is as a buffer for renewables while building up the storage for dry year back-up. This is also mentioned in Megan Woods' cabinet briefing paper.

50 Operating solely for dry year security by limiting its operation to set thresholds could
risk distorted market signals and result in higher prices at times of scarcity and less
private investment in other renewable generation. It would likely prevent it
contributing to managing calm, cloudy periods of low wind and solar generation, and
to unforeseen supply emergencies. Having set triggers for when a pumped hydro
scheme operates could also reduce its revenue and make it more susceptible to
gaming.
51 Conversely, operating on a continuous basis means that the asset can be used much
more efficiently, and support security of supply through a broader range of system
challenges (including future calm, cloudy periods, and events like that on 9 August
2021). If operated on a continuous basis, it could be broadly revenue positive, though
will have significant variability in its revenue between wet years (where it would be a
net consumer of electricity as it pumps and stores energy) and dry years (where it
would generate and draw down on its storage).

https://www.google.com/url?sa=t&rct=...ZtjMqlbdqaGUDr