Hi Shadow,
You're right - I'm not. I'm an easy target! But this isn't about me, but about the whole Blakers Australian National University team comprising Andrew Blakers, Matthew Stocks, Bin Lu and Cheng Cheng.
"The energy of a hydroelectric system refers to the amount of energy stored as potential energy in the upper reservoir. It is typically measured in Gigawatt-hours (GWh). A reservoir with 10 GWh of storage could operate with power of 1 GW for 10 h.
The head refers to the altitude difference between the water intake and the water egress. Since the cost of most components is largely independent of the head, a larger head will generally allow cheaper electricity generation and storage on a per-unit basis. Typical heads are in the range 100–800 m, although larger and smaller heads are sometimes used. The electrical power generated by the water as it passes through the turbine is equal to the product of the head (in metres), the water flow rate (in l s−1), the gravitational constant (9.8 m s−1) and the generation efficiency.
The efficiency of generation is about 90%. This means that 10% of the energy stored in an upper reservoir is lost when the water passes through the turbine to produce electricity. In a complete PHES cycle, water is pumped from a lower to an upper reservoir and at a later time returns to the lower reservoir, with a round-trip efficiency of about 80%. In other words, about 20% of the electricity is lost in a complete pumping/generation cycle.
For example, a flow of 100 m3 of water per second through a turbine/generator operating at 90% efficiency in a system with a head of 570 m will yield electrical power of 500 MW.
http://iopscience.iop.org/article/10.1088/2516-1083/abeb5b

Hi Fester,
As I used to say, "Denier's don't debate, they rotate." You’re starting to just rotate.

I'm glad by your silence you have conceded that a tiny decrease in performance of OLDER turbines doesn't undermine the LCOE for wind, that ONE company going out of business hasn't undermined the whole industry but just a few turbines, and that your REF link was paid for by anti-wind activists. Good.

"Every time I start doing calculations for renewable energy I stop after a short time as I realise how expensive it is. As an example consider how much electricity would cost to provide a continuous output using solar generation and closed loop pumped hydro."
There's your first mistake. Most models use a 60% wind, 40% solar ratio because wind complements solar in many instances especially over a wide enough grid. I repeat - this has been STUDIED! PEER-REVIEWED! The experts KNOW this stuff and your back of the envelope work is a strawman!

" Let's assume an average daily capacity factor of 25% and a minimum daily capacity factor of 15%."
America's EIA says solar is 29% CF! Pages 6 to 8 here will help you. http://www.eia.gov/outlooks/aeo/pdf/electricity_generation.pdf

They rate the batteries as requiring a 10% CF for firmed solar for LCOS (Levelized Cost of Storage) but I don’t know WHY they use batteries when PHES is the cheapest. (Again, SM has PHES efficiency TOTALLY wrong – it’s 80% efficiency SM!) Ah, but the fine print on page 8 admits they only model 4 hours battery storage. So their idea of ‘firmed’ solar must also rely on wind as per the Blakers model?

Hi Max,

What I understand of wind generation is that it becomes uneconomic after about 15 years, not because of the decrease in performance, but because of the increase in maintenance costs.

As for the efficiency of pumped closed loop hydro, it relates to the product of the efficiency of the pump (70-90%), the efficiency of the motor running the pump (maximum 75%), and the efficiency of the turbine (90%), so you have a range of SM's 45% to a maximum of about 60%. Note that this assumes your motor is running at maximum efficiency. At minimum efficiency you have a 30% to 40% efficiency range. So 60% efficiency is the gold standard, yet Andy B claims 80+%. Why might that be?

So how would you calculate the efficiency of pumped hydro Max? Would you try to find out by yourself or would you just take Andy B's word for it?

Hi Fester,
you're just making wild assertions without any credible source references. The efficiency of Pumped Hydro is well known. Of course there can be local variations, but there are many studies published free online if you bother to look.

"Founded in 1984 by a bipartisan group of members of Congress to inform the debate and decision-making on energy and environmental policies, the Environmental and Energy Study Institute (EESI) is a 501(c)(3) non-profit organization dedicated to promoting sustainable societies. Today, our mission is to advance science-based solutions for climate change, energy, and environmental challenges in order to achieve our vision of a sustainable, resilient, and equitable world."

70 – 85%
http://www.eesi.org/papers/view/energy-storage-2019

Then of course there's "A review of pumped hydro energy storage"
Andrew Blakers2,1, Matthew Stocks1, Bin Lu1 and Cheng Cheng1
http://iopscience.iop.org/article/10.1088/2516-1083/abeb5b

Wikipedia agrees:
"The round-trip energy efficiency of PSH varies between 70%–80%,[4][5][6][7]"
Those sources are from:-

The Economist:
http://www.economist.com/technology-quarterly/2012/03/03/packing-some-power

Dr Thierry Jacob from about 2000
Stucky Consulting Engineers Ltd
http://web.archive.org/web/20110707003324/http://www.stucky.ch/en/contenu/pdf/Pumped_storage_in_Switzerland_Dr_Jacob.pdf

PUMPED HYDROELECTRIC ENERGY STORAGE AND SPATIAL
DIVERSITY OF WIND RESOURCES AS METHODS OF IMPROVING
UTILIZATION OF RENEWABLE ENERGY SOURCES
Jonah G. Levine
B.S., Michigan Technological University, 2003
http://web.archive.org/web/20140801113053/http://www.colorado.edu/engineering/energystorage/files/MSThesis_JGLevine_final.pdf

Yang, Chi-Jen (11 April 2016). Pumped Hydroelectric Storage. Duke University. ISBN 9780128034491.

But we all know this - and know what's going on with you and SM.

THIS is what's really interesting!

"In just three years' time, the world will get more power from wind and solar sources than from coal, according to the International Energy Agency."
http://www.cbsnews.com/news/solar-power-will-beat-out-coal-globally-in-three-years-international-energy-agency/

Thanks for pointing out the error in my calculation Max, but you could have done so more economically if you did the calculation yourself. Did you notice that all those glossy brochures you referenced showed pumped hydro to be more expensive than battery storage?

LCOE Max. You wont see Andy B and his chums say much about this measure as it demonstrates what an expensive source of energy renewables are compared to nuclear.

“Did you notice that all those glossy brochures you referenced showed pumped hydro to be more expensive than battery storage?”

Which paragraph in particular from which study? See, it depends on context. Fast dispatchable for 4 hours, or DAYS of storage? Batteries for the former, PHES for the later.
“LCOE Max. You wont see Andy B and his chums say much about this measure as it demonstrates what an expensive source of energy renewables are compared to nuclear.”
I don’t think you’ve understood a thing on this thread then!
See, there’s nuclear in South Korea where it’s kind of mass produced.
Then there’s nuclear in the Western world where you can pay $10 billion per GW! I wish it were not so, but it is. Unless we were to get Australia to buy say 30 CAP1400’s which would be AWESOME and really bring the price down. But here’s the thing. Aussies hate nukes. It’s just. Not. Going. To. Happen.

We’ll be 80 to 90% renewable in just 8 years.

You’ll love us when we win.

You’ll turn around on this, and say “I always knew it would work IF we did XYZ – and look we did XYZ. So I was right after all!”

You’ll disguise it, dress it up, do anything to avoid it.

But deep down you'll know that 'we' were right - and 'we' turned out not to be crazy hippie dippie tree huggers - but hard nosed energy engineers wanting the best for Australia. (I'm not, but the people I read are.)