I find it strange that this is all of a sudden back, and fast tracked at that just after the recent news about the data centre in Southland.
I find it strange that this is all of a sudden back, and fast tracked at that just after the recent news about the data centre in Southland.
What’s the difference from today? With pumped hydro at least you have somewhere to send excess power generation.
One important thing here is about the ramp up time. I wasn’t able to find anything that explains about how long it takes for a hydro power station to start producing when it’s off (and equally, to stop when it’s on). It feels like it should be quick, open a gate and the water falls and spins the turbine, surely this can happen within seconds or minutes?
If that’s the case, then loading up on solar should effectively balance out the water usage, so you could generate heaps of power on sunny days and use no hydro, then bring hydro online to help cover the night.
At the moment I believe hydro is used a lot for covering the base load, but if it can be turned on and off quickly there’s no reason that needs to be the case. But if it takes hours to turn on or off a hydro station, then the argument for pumped hydro is stronger since you can pump while it’s running (using excess solar generation).
You are mostly correct, hydro is used as base load rather than storage.
The use of hydro is dictated my market forces rather than efficiency.
Hydro ramp rates are fairly fast 15-30 minutes, usually faster because you are not going from stopped to 100%
Batteries should be used to buffer short term fluctuations, these can ramp up in seconds and hold for a while to let the hydro catch up.
Battery storage at grid scale is pretty new, and I don’t think NZ has any yet (just a planned one up north). A big downside too batteries is they will need replacing a lot, I hope we have appropriate recycling facilities to handle it.
One of the main benefits of hydro is the longevity. If you go big then you can build something that will still be going 100 years from now, making a very low cost per watt over it’s lifetime. The scheme in the OP seems like it’s building a whole new dam, they must think that adding the pumping to is is worthwhile otherwise they would just build the dam without the pumping component.
I’m curious what you meant by that, that we use hydro because it’s cheap?
No, they use hydro because they get money now rather than using something else and save the lake level for traditionally dry periods.
Also, over the last decade nonrenewable has been installed at great cost, this is not due to the best choice for everybody, but because the power companies get significant return.
It is really hard to justify anything against solar right now, but we are installing a very small amount.
Our power scheme does seem to incentivise scarcity as then the generating companies get paid more for generating the same amount of power. I see what you mean now about a government owned and coordinated hydro scheme, where hydro is used when it’s the best option instead of when it pays the most.
Are we? Every time I turn around a new solar farm seems to pop up.
In a well run system we would install 10 times as much, while retiring the dirty, expensive and maintenance heavy old plants.
Honestly, the $16B being used for this scheme, spent on solar and and battery would deliver a much greater benefit to NZ, but would ‘crash’ the price of power to historical lows, thus meaning that the investment would be self defeating.
The flow on benefits from such low power process would more than pay for the investment
Haha I keep forgetting that most importantant point. I think building a giant hydrodam would pay for itself over time and provide a lot of much needed power, but I keep forgetting about the opportunity cost! The “what else could we spend $16B on” part of the puzzle!
Yea, to me it is an efficiency problem.
There was an analysis done for the LPG terminal @ $2.7B over 15years. With the LPG we would get just over 1TWh of energy; but the same money, spent on solar would get 1TWh every year.
Extrapolate that out and you would be hitting 5TWh every year with solar. NZ uses around 120GWh/day. Adding 5TWh/yr (would add 13.7GWh/day) or more than 10% of our total generating capacity.
The other thing to remember; is that this is not a generation asset; it a demand shifting system. Very useful, but it doesn’t bring new capacity online, where as the same money spent on solar would bring significant new capacity online.
I may have misunderstood, but isn’t this $16B project to build a brand new dam and brand new hydro generation capacity? It sounds like this hydro would add 8TWh of annual generation capacity:
The pumping part is the demand shift, but the project appears to add significant generation capacity even without the pumping part.