Not sure where the 80% figure comes from. I live adjacent to the Snowy Mountains and used to work in an engineering office in Cooma. I was told at the time by engineers managing Snowy hydro that the "off peak" coal power was used to pump water back up hill between storage's as a "Hydro battery" as a way of increasing the utility of the scheme, which had to balance electricity demand with releases for irrigation. This also provided a useful load for the thermal power stations in the Hunter Valley that had to keep their turbines spinning. The claimed efficiency of this at the time was 6% of the energy used to pump the water.

What is the real number for pumped storage?

Wow, well it has to be somewhere between those two numbers, eh?
Pumped hydro is an excellent method of storing kinetic energy directly but requires the proper geology. A dam in proximity to a mountain lake.

This topic is huge and hugely interesting.
Using the electricity produced by a hydroelectric dam to manufacture solar cells is a form of energy storage.
The lower (and greener) the cost of production, the faster the energy deficit is recouped and the longer the panels can harvest sunlight.

Stored compressed air can be used to turbocharge natural gas turbines and make them burn cleaner and more efficiently.
Liquid salt thermal storage is proven and reliable and durable. Strides are being made in the geometry of mirror arrays to heat it.
Electric car batteries will prove to have a great utility value for the homeowner and a large secondary market is expected for them.
Those flow battery specs are impressive. Especially the cycle capacities.

Strides indeed:
http://cleantechnica.com/2012/02/06/twin-solar-thermal-plants-commence-operation-in-spain/

George Monbiot says it isn't so.
He writes for The Guardian and The Age and the SMH, so he must be correct.
http://www.smh.com.au/opinion/politics/batter-up-oil-enough-to-deepfry-the-lot-of-us-20120703-21fbi.html

And they could be sold without any identification, in the same way that RAM was often stolen and onsold.
Battery rebirthing?

Interesting that compressed air seems to be cheapest. And I imagine you could do it pretty much anywhere.

Gary,

No, compressed air energy storage cannot be done anywhere (it needs suitable geology). Also it uses gas. And it is not suitable for the scale required. See the other charts.

So 10c / kwH is orders of magnitude too expensive?
http://www.electricitystorage.org/images/uploads/static_content/technology/technology_resources/cycle_large.gif
Am I reading that wrong?

Gary,

Let’s look very simply (limit analysis to get a ball park picture) of costs to power the NEM with PV and energy storage. PSH and CAES cannot do it because of suitable sites are not available. The next best option is probably NaS batteries. Let’s do a simple analysis. Here are some inputs:

NEM peak winter demand = 33 GW
NEM average demand = 25 GW
NEM minimum demand in winter = 20 GW
Energy supply for 10 days = 6000 GWh
On overcast days, say 20% is supplied by PV and the remainder from storage
Supplied from storage = 4800 GWh

Capital cost = 4800 GWh x $0.2 billion/GWh = $960 billion

Add PV capital cost
(average power / winter capacity factor over worst 10 days x capital cost per GWh output)
(assume PV minimum capacity factor in winter = say 10% over worst 10 days)

= 25 GW / 0.10 * $0.3/GWh = $75 billion

Total capital cost = $1 trillion

Capital cost for gas turbines to do provide us with a more reliable supply would be = $40 billion

For 75% nuclear 25% gas would be about $100 billion.

Financing costs and O&M must be added to all these figures and fuel must be added to gas and nuclear (nuclear fuel is just 3-5% of the cost of nuclear electricity generation and, for those who inevitably ask, yes that cost includes waste management/disposal).

So, in answer to your question, yes as I said above: “Energy storage is orders of magnitude too expensive to make intermittent, unreliable, non-dispatchable renewable energy technologies economic.”

If you’d like to read about this in more detail see: “Solar power realities – supply-demand, storage and costs” http://bravenewclimate.com/2009/08/16/solar-power-realities-supply-demand-storage-and-costs/
No one is suggesting that the NEM would be powered by PV and NaS batteries alone. It is just a simple way to get an understanding of the total costs. Many costs are buried, hidden and pushed onto others when we pick away at bits of the problem. This limit analysis approach exposes the real costs.

This will give you an idea of the costs to power the NEM with renewable energy (wind, solar thermal with storage, PV and biofuels):
http://bravenewclimate.com/2012/02/09/100-renewable-electricity-for-australia-the-cost/

You have used 20c / kwH in your calculations. This is the upper end of NaS costs and you have completely discounted Pumped Hydro and other cheaper options - why is that?

I note from your links that you are a proponent of nuclear power. What do you think of Thorium?

Gary,

No. 20c/kWh is near the lower end. It is a log scale. 20c is a little below half way between 1c and 100 c.

(Are you looking at the correct figure? this one: http://www.electricitystorage.org/images/uploads/static_content/technology/technology_resources/capital-cost_large.gif ).

I trust after you have read and understood what I've provided above you'll feel able to acknowledge the point I made.

Did you find the two links I provided of interest? If you haven't looked yet, and if you are genuinely interested in the cost of renewables, I'd urge you to consider them (I'd suggest you download the PDF and read it because it contains the appendicies).

Gary,

Sorry, I've made more errors in writing the previous comment, but there is no change to the result.

Wrong sentence says: "No. 20c/kWh is near the lower end. It is a log scale. 20c is a little below half way between 1c and 100 c."

The sentence should read:
"No. $200/kWh is near the lower end. It is a log scale. $200 is a little below half way between $100 and $1000."

These figures are the cost for enery storage capacity that would be required (very roughly).

My original estimated capital cost for the enegy storage capacity is unchanged at $960 billion. I revised up the estimated capital cost of the PV from $75 billion to $125 billion. This is a very rough estimate for reasons explained.)

The total cost, therefore, would be about $1.1 trillion, which is around the times the cost of a nuclear solution which is also near zero emisisons).

I am looking at this chart:
http://www.electricitystorage.org/images/uploads/static_content/technology/technology_resources/cycle_large.gif

which takes into account the lifetimes of the technology and breaks the costs down into cost per kwH of energy stored/discharged.

The costs range from 0.1 to ~2c per kwH for pumped hydro. Flow batteries anywhere from 100 down to 5c and 9 to 20c for NaS (but again the exponential axis - hard to tell exactly).

So if you average it out it looks like 10c/kwH per cycle. Certainly not "orders of magnitude too expensive".

I really am genuinely interested in your opinion of Thorium.

Gary,

We can get to your questions about thorium later. Let’s resolve this cost of storage issue first.

You are misunderstanding the chart you are looking at. It is not the Levelised Cost of Electricity (LCOE) (which is what you are looking for). The figure you are looking at is pretty meaningless the way it is presented. It could also be misleading for many readers who do not fully understand what it is.

To calculate Levelised Cost of Electricity (i.e. in c/kWh or $/MWh), which is what you are asking about, you need additional information, including:

- economic life (years) of the investment - say 20 years
- discount rate - say 10% (10.1% (before tax, real) is the figure used for the technology comparisons in the Energy White Paper and recent studies by government departments such as DRET, AEMO etc)
- the equivalent to capacity factor
- O&M costs

The financing costs alone would about triple the figures you've asked about. Therefore, very roughly 30c/kWh compared with about 3c/kWh for existing coal generation. You also have to add the cost of the renewable energy generation and the transmissions costs. If you look at the links I provided above you will get an understanding of this.

I’ve now provided three entirely separate calculations all of which support my original statement. I’d appreciate your acknowledgement that you accept this before we go on to other questions you may have.

I appreciate your condescending tone Peter - and I don't doubt that you know more about the technicalities than I do. What I do doubt is your objectivity.

Your figure of 30c/kwH is still not "orders of magnitude too expensive". To be "orders of magnitude too expensive" (plural) it would have to be at least 100x too expensive. Also you have still not explained why you have completely discounted pumped hydro and other cheaper technologies.

Gary,

Thank you for your further response. You say:
“I appreciate your condescending tone Peter - and I don't doubt that you know more about the technicalities than I do. What I do doubt is your objectivity.”

Sorry if my tone seemed condescending. Given the many comments from you in the past, where you have made condescending statements, unsubstantiated assertions and have invariably refused to acknowledge when you are wrong, I’d ask you to consider whether your opening remark is appropriate or constructive.

I’ve given you three totally different analyses, all of which showed the cost of electricity using storage to be an order of magnitude higher than our current wholesale price. Some of those estimates are substantially more than an order of magnitude higher. I also gave you links to assist you to understand. You have not acknowledged that you have read the links. Especially you have not acknowledged that you recognise what I am saying is correct.

Most of the figures I gave you were much higher than 30 c/kWh yet you choose to use this one, despite me explaining why it is not appropriate. Furthermore, you seem to be comparing 30 c/kWh with retail prices. You need to compare it with wholesale prices. But anyway, it is not the correct figure to use as I explained in an earlier comment.

If you read the link I gave you, you will understand why pumped storage hydro is not a viable option for Australia (please read it; you’ll find charts showing the costs and the area of land that would be inundated if we could find appropriate valleys where water could be held in pairs of dams separated by say 150 m or more vertically and within a short horizontal distance of each other). Once you’ve read it, that would be the appropriate time to ask questions about what you don’t understand, don’t you think?

You could also read this (and the answers to questions you may have in the comments): http://bravenewclimate.com/2010/04/05/pumped-hydro-system-cost/

The reason I haven't been able to admit I am wrong is because you haven't convinced me. I don't have the time or the background knowledge to go through every line of your analysis and question every one of your assumptions and the only links you provide are links to more of your own analysis. How about some expert opinion other than your own?

It's good to see that you have backed off the "orders of magnitude" bit - what about the "not chanve[sic] of ... becoming commercially viable"? Can you see into the future?

Feel free to admit you are wrong about making such an unsubstantiated all-encompassing statement.

I am sorry - I am getting condescending again. It is what happens when I see people making ridiculous assertions.

BTW Questioning someone's objectivity is quite appropriate.

Gary,

“ It's good to see that you have backed off the "orders of magnitude" bit - what about the "not chanve[sic] of ... becoming commercially viable"? Can you see into the future?

Feel free to admit you are wrong about making such an unsubstantiated all-encompassing statement.

I am sorry - I am getting condescending again. It is what happens when I see people making ridiculous assertions.

BTW Questioning someone's objectivity is quite appropriate.”

I sort of knew it would end up like this: you not admitting you are wrong; you can’t be bothered trying to understand the answer; you won’t read the links (or the links referenced within); I give you other links and you say give me more; then you make dishonest and misleading statements saying I’d made a wrong claim and should admit I am wrong. I am not wrong and I explained and gave you the evidence repeatedly.

Your behaviour here is an example of what the CAGW alarmist do all the time, and it is why they’ve lost their credibility. I find the sort of behaviour you display is unprofessional and distasteful. I don’t trust people who behave as you have here. I’ve wasted all this time answering your questions and you cannot even acknowledge that you’ve been given the answer you were seeking.

You say (including smart and condescending remark about a spelling error):
“what about the "not chanve[sic] of ... becoming commercially viable"? Can you see into the future?”

The answer is provided in the links I’ve given you. Renewables will nbot be viable for providing our electricity supply. Not only because of the cost, but also because of the resource requirements. Read the links. There is no point me rewriting it here because it is clear you don’t want to hear what doesn’t support you ideological beliefs.

You should question your lack of objectivity. You’ve clearly displayed it here.

It is clear you are just another ideologue who is not interested in the facts but wants to continue to believe renewable energy with electricity storage can be cost competitive despite it being not viable by an order of magnitude.

Thank goodness the population is beginning to realise how badly they’ve been misled by you and your ilk.