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