The great energy debate

It took me a little while to track down the details of the Spanish solar installations.

The first two are small at 10MW (this wouldn't power our feed pump for one unit at work) and 20MW. The third installation is the one with the salt beds. They are all what I call solar thermal in that they heat up a tower to produce steam, which in turn drives a conventional steam turbine.

This is the link:

http://www.cleanenergyactionproject....ar%20Plant.pdf

You have to read down a little way to get the story on their reduced output by heating the salt beds.

"Because of the large storage capacity, the output capacity of the turbine is smaller than would be expected from a plant of its size. While the thermal receiver has a 120 MW thermal capacity, the generation plant only employs a 19.9 MW turbine."

That is in fact a six to one ratio by my reckoning so there are considerable losses in storing the heat. The pictures also show another drawback. That of the huge amount of space they occupy. The 20MW plant occupies 75 acres. The power station I work at is small at 870MW (the previous one was 2640MW and has been increased in size since then). A solar installation of the same size would occupy 3225 acres. My previous station would require a solar equivalent of 9900acres.

Of course in Australia we have vast tracts of hot land, but that is not where the people are and the transmission costs are too expensive. Places like Mt Isa and Broken Hill are not on the general grid for that reason and are stand alone systems. Just too far away.

Sorry to sound negative. I don't mean to be and in fact I firmly believe that once the government stops pandering to the lobby groups of the various interested parties, alternative energy development will accelerate at an exponential rate. The playing field needs to be leveled.

Two days ago I had a talk at work with one of the managers as part of an interactive discussion programme. This manager is not one to whom I report and that is a deliberate strategy. One of the questions he put to me was how do I feel about working for the company and am I comfortable working for them. I pointed out that if I have to work for an environmentally polluting electrical generator this is probably the best one I could choose, but I am looking forward to the day they build a solar plant so I don't have to apologise to people for placing CO2 into the atmosphere.

That probably tells you a bit about where I stand on the alternative energy options, but at this point in time I don't see them as economically viable......I would very much like them to be. That time is still to come and it is getting closer.

Regards
Paul

OK, this may be a bit rambly and long.
I noted before that, like Bushmiller is now, I was an operator at a power station. You can see from my profile I am in SA and it doesn't take to much to work out where that might have been, just the same as we can readily tell where Bushmiller is.
I'll give a little of my history and then I'll make some comments on the discussion so far. Noting that nothing that I can see so far has been outright wrong and a lot of it is correct (if limited).

I _was_ an operator more than 25 years ago (whew, that does sound a long time now that I wrote it down) but it was an old station even then and to "get on" I got some further pieces of paper that allowed me to move to more "senior" areas of work. For a time I was involved in some interesting areas of work, including being involved in a total power station refit and I was later the site representative for the sale/privatisation which happened in the late 90s in SA. I moved out of generation about 15 years ago, but am still in a closely related area in the electrical industry. My thinking on the future of many things has changed over the years.
In the 90s I believed that most fossil fuel stations would run, almost forever, with continual refits and upgrades. there was evidence of this in the US of stations built in the 30s being kept going 50+ years. Callide A in Australia seemed to be another one. However, there was starting to be evidence, even then, that greenhouse gasses could be an issue. If you think this has been an issue of the last few years you are really wrong. As part of the power station sale process I saw documents that indicated some sort of carbon price was expected by purchasers within the next few years (ie they expected to see a carbon tax in the early 2000s). Frankly I am surprised the carbon tax took so long to implement. My view is, when the carbon tax or some form of trading is reintroduced (and it will be) the remaining fossil fuel stations will take a hit. (Bushmiller, at least one of the _hidden_ subsidies Millmeran and others have is the free disposal of pollutants, CO2 being one. Economists call them "externalities" but what they mean is a cost that is too hard to work out, so they just ignore it).

So about 2000 I left the power station, mainly for my kids future, but also I had doubts about the medium term longevity of the station itself. As I type, that station is closing and guys I worked with for years, some of who I went to primary school with, will be finished up in about 7 months time. This has not been a surprise to them as it has been on the cards for a few years. I thought the carbon tax would do for them, in the end it appears to have been the wind farms.

So baseload...
As others have said, baseload is a bit of a furphy, and bear this in mind with Bushmillers 100MW machine example, which is correct as a first approximation (and also his points about the Spanish solar thermals) but the likely real situation is more dynamic than that.
Once a long time ago when generators were just becoming commercial it was difficult to get a steady load throughout the day.
Efforts were made to smooth out the load by giving people discounts to use power in the evening, such as electric hot water heating. But it turns out that a large part of the overall load is daytime load, unsurprising as thats when most people are awake and doing stuff, which aligns very nicely with solar PV generation. In fact if we do the opposite of what we did all those decade ago, and encourage power use during the middle of the day, solar would be an excellent match. Of course, it can't do everything and we still need to cover the times when it isn't available. That is where batteries etc come in for individuals and wind and fossil (and theoretically nuclear) for the overall system.
Another side effect of PV means that the power an individual house needs is reduced, so the utility wire might be OK to be smaller. In fact even if you don't have PV but those around you do, it means they support your load locally and the power required by the whole area reduces (and so does size of wires, transformers etc). This is a very interesting technical problem (as in the Chinese curse, may you live in interesting times!)

Do we need fossil fuel...
Well I have thought all my working career, yes. But now I am not so sure (talking only electric generation here). I have seen interesting papers which plausibly suggest we can get away without it. So what is the state of fossil fuel in SA, and Bushmiller is correct that different places have different circumstances so what is true for SA may not be exactly so for other places. BUT what SA shows is that there can be places where the circumstances are right. If you hear anyone say wind (for instance) can't replace coal (or gas or whatever) as a categorical statement, they are simply wrong.
The current state of SA generation is this. Coal power will be shut down next year. It is dead in SA and will never come back. Even without the carbon tax the particular power station was struggling to compete in the market (it was in 2000, it always has been*). In fact the last few years it was taken offline for 6 month winter periods, to reduce market losses. Their breakeven cost was usually higher than the market rate. And this is the interesting bit. When you hear the discussion that subsidising wind power means that the subsidy "costs" money and is passed on to the consumer so electricity is "more expensive". That is only half the story. Once the wind generator is in the market, its fuel costs are zero and it can bid in at much lower costs, which the other generators have to compete with, driving down the overall cost of electricity in the market. So we can get to the stage that subsidising wind, drives the total price down. This isn't guaranteed as the subsidy and the savings counter each other. But I think that is where SA is, ie our savings have been greater than our subsidy.
As for gas, there are two baseload stations and a few smaller turbine peakers in SA. The biggest of these is permanently half shutdown and the other is in hiatus for the foreseeable future. So, SA currently has/will shut down or indefinitely taken off the grid; coal generation of approx 780MW, and gas 960MW _all base load_. To get that in perspective SA typically runs 2000+MW loads daily average and summer peaks a bit above 3000MW. And 1750MW of fossil fuel "base" load has now been taken out of the system.

(*There are technical issues which Bushmiller may be interested in but which aren't relevant here. Was subcritical Benson type boiler which meant it ran very badly in any role other than base load and with no top drum couldn't really make any money from ancillary services either, plus had coal transport costs. I think, the average generation cost was about twice Millmeran, but Millmeran also has economies of scale not available in SA too)

Nuclear?...
Will never happen. Forget all the stuff about NIMBY and radioactive pollution and capital costs and government subsibies to make them profitable which are all big problems. There is a simple technical problem which is never talked about. A single generator cant be too big in a system. Think about if all NSW was fed by one generator and it tripped for some reason. Everyone loses power till another station starts up. Rough rule of thumb a generator cant be more than about 10% of the total system. As above SA about 2500MW, NSW about 7000MW (from memory) and QLD somewhere between (Bushmiller?). The smallest commercially available nuclear power generator is 800MW. It is too big to use in SA (by a very long way). Too big for Qld and Vic, maybe marginally possible for a location somewhere around Sydney if the NSW grid grows (and then the political issues will kill it, like it did in the 70s).

The future...
Some things take a lot longer to happen than you might think due to difficulties to implement (eg technical development) and underestimated blocks (political opposition from negatively affected parties), but often, when they do go they go in a rush (a paradigm change was the buzzword) and the changes take people by surprise.
Bearing in mind my views have morphed as time passed, I think this is what will happen, and it will happen at various rates in different places:
Solar thermal we wont see for decades (but it will displace fossil peakers when/if it comes).
Nuclear, in Australia we will never see.
Wind and solar (PV) will continue to grow and displace fossil fuel especially those that consider themselves base load now.
Transmission and distribution systems will still be needed, but they will be smaller (due to increases in local generation, mainly PV) and older (because what we have now has to last) and a big headache to their owners.
There will still be fossil fuel, but less than we have now (and zero in some areas).
The fossil fuel will be peaking types, mostly gas turbine based.

Regards
SWK

That was an interesting read, and a view on nuclear power viability I hadn't heard before.

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Originally Posted by DonIncognito

That was an interesting read, and a view on nuclear power viability I hadn't heard before.

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+1 Indeed it was.

Perzackly what is baseload then? I know it's for industry, and therefore big draw, but is it still 415v and very large amperes, or.......

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Originally Posted by swk

(*There are technical issues which Bushmiller may be interested in but which aren't relevant here. Was subcritical Benson type boiler which meant it ran very badly in any role other than base load and with no top drum couldn't really make any money from ancillary services either, plus had coal transport costs. I think, the average generation cost was about twice Millmeran, but Millmeran also has economies of scale not available in SA too)

Nuclear?...
Will never happen. Forget all the stuff about NIMBY and radioactive pollution and capital costs and government subsibies to make them profitable which are all big problems. There is a simple technical problem which is never talked about. A single generator cant be too big in a system. Think about if all NSW was fed by one generator and it tripped for some reason. Everyone loses power till another station starts up. Rough rule of thumb a generator cant be more than about 10% of the total system. As above SA about 2500MW, NSW about 7000MW (from memory) and QLD somewhere between (Bushmiller?). The smallest commercially available nuclear power generator is 800MW. It is too big to use in SA (by a very long way). Too big for Qld and Vic, maybe marginally possible for a location somewhere around Sydney if the NSW grid grows (and then the political issues will kill it, like it did in the 70s).

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Thanks SWK for a most interesting and well thought out post.

I would like to think that you are right about nuclear power not getting a look in here in Australia. Until they work out what they are going to do with the waste I don't believe it should be given the time of day. There are a whole host of problems associated with the nukes, but I won't go down that track again.

I noted that most of your time as an operator was spent in SA, which apart from Tassy has the smallest load demand out of the Eastern states. The nature of the load has changed significantly in the last fifteen years. The peak power demand used to be in winter. During the start of the 21st century it changed to a peak summer demand, which of course suits solar.

The generation demand generally has decreased. In years gone by I saw almost 14,000MW in NSW and almost 9000MW in QLD (can't remember VIC but probably 10,000). Typical demand in NSW now would be around 9000MW, QLD just under 7000MW and again I can't recall VIC. SA is about 1800. Add ten to fifteen percent to those figures for extreme conditions.

Generally the largest generators are in NSW where they have twelve 660MW machines installed across four stations (Bayswater, Eraring, Vales Point and Mount Piper). I believe these machines have now been upgraded in varying degrees up to 725MW or slightly more.

The largest individual unit in Australia is in fact in QLD ,being the giant (for Australia) 780MW unit at Kogan Creek. Of course your comment that the generators have to be of a compatible size for the system is quite correct. I was amazed when I heard about Kogan Creek being built as it was out of kilter with anything else up here (I think 450MW is the next largest). To some extent the whole of the eastern seaboard is linked into one grid. I qualify this by pointing out that there is only a partial exchange of power possible between states because of limitations in the transmission lines. So QLD cannot supply all NSW's power and VIC cannot totally supply SA. Think more like ten percent.

However, what those larger units does mean is that, if the minimum size nuke is 800MW (I don't know what sizes they come in, although the US definitely has some 1300MW sets) it is not inconceivable that it could happen here. I believe that more of a barrier at the moment is the huge capitol cost of the nukes combined with the fact that power stations in the future in Australia will probably only be privately owned. I have not gone into the relative costs of operating a nuke, but hopefully, they are unlikely to be able to compete with our cheap sources of power, which for the moment are thermal, but may well be in the future, solar and wind to name two.

Regards
Paul

Bushmiller, SWK & others, thanks for making this an interesting discussion rather than an argument, and for your informed contributions which I, for one, have found most educational.

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Originally Posted by Bushmiller

I noted that most of your time as an operator was spent in SA, which apart from Tassy has the smallest load demand out of the Eastern states. The nature of the load has changed significantly in the last fifteen years. The peak power demand used to be in winter. During the start of the 21st century it changed to a peak summer demand, which of course suits solar.

The generation demand generally has decreased. In years gone by I saw almost 14,000MW in NSW and almost 9000MW in QLD (can't remember VIC but probably 10,000). Typical demand in NSW now would be around 9000MW, QLD just under 7000MW and again I can't recall VIC. SA is about 1800. Add ten to fifteen percent to those figures for extreme conditions.

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Paul,
ALL my time as an operator was in SA :U
I assume your numbers are from AEMO and more up to date, mine were from memory somewhat but SA summer record peak was about 3400 in 2010/11 and slightly lower in 2013/14. Last summer was lower but this next summer will be interesting as the El Nino looks like it is on the way. We'll see if the PV can really lop the summer peak. The AEMO data does not include PV which is only estimated and not included in the generation stats (as far as I know) and which is another reason the thermal stations took a hit, but yes SA is small and the demand has decreased somewhat. SA always used to get bigger summer peaks from at least the early 80s so that hasn't changed for us.

As for nuclear, like I hinted, stability issues really limit where a commercial generator can be located due to their size. I said minimum size is 800MW but these are older designs generation 3 (look up CANDU in google if you are interested, the Indian nuclear program is based on this reactor and I think some of the European ones too). I think the actual up to date ones, generation 3+, are in excess of 1000MWe.
There are generators smaller than this but they are either old (Magnox type, really used to make material for nuclear weapons) or not developed yet (integral fast reactor). The new ones won't get a look in for at least a couple of decades as the developmental costs and risks are too great, the companies that tout them will not develop them unless they are assisted by government money (at least the more reputable western companies).

Regards
SWK

SWK

The disturbing point I was making was that in QLD the authorities approved a generator that was getting on for twice the size of the next nearest unit.

It is because of this alarming development that your very sensible and logical premise may be tested down the track. I very much hope that you are right.

I think Kogan Creek may have been the last coal-fired thermal station built in Australia.

Millmerran power station was built by the American and I was here during commisioning. The American crew had an alarming rate of chronic sickness and, yes, they had all worked on nukes.

Now I am sure the protagonists will say, but that was the old reactors. Well maybe....


Regards
Paul

Fence furniture,
no, not really. The baseload hasn't got anything directly to do with industrial, domestic etc. In its simplest it is the minimum amount of power which is always needed in a system.

Imagine a 24 hr day in 4 quarters.
Midnight to 6am most people are asleep, but there are still street lights, hospitals and maybe some factories. To Make up some numbers, say 500MW of power is needed for these.
6 till mid day, people get up and go to work the load increases to 800MW.
In the arvo, 12 till 6pm industry is flat out people working hard say 1000MW, then in the evening everyone is home, cooking tea, watching telly before bed etc say back down to 700MW.
And this cycle repeats every day.
We can think of this as a "base" load of 500MW with an additional 300/500/200 MW "peak" depending on the time of day.
(Of course it isn't blocks, its a smooth curve and there could be more than one peak and other things affect the daily cycle. Weekends are different from weekdays and winter is different to summer, but these complications aside this is the concept).

Now, if you are a command economy like China or a (semi)state run enterprise like the old Australian electricity commisions, the obvious solution to your planning is to have 500MW worth of generators which run all the time (base load) and another set of generators which you can run up and down each day (for the peaks). Anything that makes a steady amount of steam to drive a turbine and generator is good for base load, in fact they really don't like changing loads. Run them flat out and steady for months (coal, gas or nuclear) is best*. Cover your peaks with gas turbines (comparatively expensive, high maintenance etc), hydro (capital expensive) or diesel (expensive fuel) generators which can be started and stopped quickly.

*In fact, if you can spread out some of that peak across the full 24 hrs of the day (instead of having 500/800/1000/700 we can get 700/800/800/700) you can have more easily managed base load machinery and less expensive peaking, which is why you as a consumer might be able to wangle cheaper electricity at "off peak" times.

So about 20 years ago there was a bright idea to create a national market of electricity because that would be more efficient than the old long term state planning. Bushmiller said;
"I recall when the competitive market was first mooted nobody knew exactly how the competitive aspect would pan out except there would now only be three concerns:
Price: Price and Price."

And now the system is driven by what is cheapest. So instead of a planned system with an orderly use based on the most suitable type of machine, whoever can undercut the others gets to make money and whoever misses out doesn't make money that day (in fact loses it in overheads)
Back to our system using 500/800/1000/700 in a day. We introduce 100MW of renewables and everyone ignores it because it is too small and puny to make much difference. Say its solar power. It can generate say between 6am and 6pm although the quantity might be less than its rating. It is competing with the peakers, but because every MW of solar is cheaper, whatever they generate will displace whatever the peakers used to generate. The peakers now don't have the income they used to have. Hmm... nothing stops them turning around and competing with baseload if their cost structures allow it. So the cheapest of the peakers can knock out the more expensive base load during some parts of the day.
Now someone puts 100MW of wind into the system. Wind also might not always give its full nameplate rating, but it can operate at different times during the day and, same as solar, it is cheap and will be preferred generation so all the wind generation will sell into the market, and this time on some days when the wind is blowing after midnight, it competes directly with the base load stations as well.

But remember the base load generators really weren't meant to run their load up and down, particularly if they come off all together it can takes hours (days!) to get back on. In an effort not to come off some of the more desperate base load will bid into the market free. They will generate for free for a short time because it costs less than coming off and back on again. In rare cases they may even _pay_ to generate. How long is that business model sustainable.
Eventually the more expensive peakers and base load go bust and drop out of the system. And then, in theory, after a while the price of electricity goes up and it becomes favourable for investment and private investors will add more competitive generation to the system. However, now we have that paradigm shift. No private investor is going to shell out billions (really) for a big power station (coal, gas or nuclear) where the market risk is so high and chance of return is so small. Instead they will invest in a lot of smaller and distributed generators, which is why a point comes where wind farms and PV farms spring up everywhere and big thermal stations become a thing of the past.

The buzzword is disruptive technology.

And part of the reason this happened/is happening in SA was because after 1985 the state government didn't invest in generation, so SA was poised to go down this path earlier, but barring some big game changer (like climate change??) the other states will follow in time, although it might be some time for states with newish infrastructure (like QLD). Any form of carbon tax/trading will also give it a kick along.

Regards
SWK

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Originally Posted by Bushmiller

The disturbing point I was making was that in QLD the authorities approved a generator that was getting on for twice the size of the next nearest unit.
It is because of this alarming development that your very sensible and logical premise may be tested down the track. I very much hope that you are right.

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I don't know how it is done in QLD, but I am sure that choosing one unit was a commercial decision by the investors, based on certain assumptions, and the stability issues were reviewed by someone independant in QLD (regulator or NEMMCO?). It will be interesting to see how the future of that station pans out. IE were the original assumptions reasonable. How many times has Kogan Creek been resold (that might be a clue to how well it is doing)

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Originally Posted by Bushmiller

I think Kogan Creek may have been the last coal-fired thermal station built in Australia.

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I think you are absolutely right there.

Regards
SWK

I agree with Alex's sentiments. The thread is a fascinating read, with loads of background and detail. Thanks to the major contributors, in particular swk and Bushmiller.

So, the question is, should solar energy fit-outs for households be subsidised or not? Obviously the main power generators wouldn't think so and could be expected to lobby hard against it, but surely that would have to go a reasonable distance towards achieving a "proper" reduction (i.e. >26%:~). After not too long the investment for each household is recouped - perhaps the govt could recoup the subsidy from electricity fed back into the system for a period.

Just a thought, and no doubt there are downsides to it.

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Originally Posted by FenceFurniture

So, the question is, should solar energy fit-outs for households be subsidised or not? Obviously the main power generators wouldn't think so and could be expected to lobby hard against it,

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Brett

The burning and most emotive question of all. The alternative energy industry and in this case solar had to be given a kick start. Without it the necessary development was just not going to occur. The irony was that the subsidy itself pushed up the price of the installations!

Speaking for myself, I took out a loan to afford the solar panel installation. At the time I calculated it would take a minimum of eight to ten years to break even. So a way of looking at that is that I am subsidising the market for that period of time. Agreed, if the panels and associated equipment last the distance, I will make some money after that time.

Regards
Paul

I was scaning the TV programmes and saw this on SBS about a show on uranium:

"In our energy hungry, warming world, uranium both tempts with unbelievable power and threatens all life on earth. Destroyer and saviour, dream and nightmare: the extraordinary paradox of uranium."

I thought it was appropriate having regard to earlier comments about the "nukes."

Regards
Paul

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Originally Posted by Bushmiller

The irony was that the subsidy itself pushed up the price of the installations!

Speaking for myself, I took out a loan to afford the solar panel installation. At the time I calculated it would take a minimum of eight to ten years to break even. So a way of looking at that is that I am subsidising the market for that period of time. Agreed, if the panels and associated equipment last the distance, I will make some money after that time.

Regards
Paul

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Surely that can be put down to rorting by the installers, just as there was with the doomed insulation fiasco.

It sounds like you went solar a few years ago? If that was the case then the time to recoup investment is still +- a similar time. Panels are apparently significantly cheaper in the last couple of years or so, but the return for putting lecky back into the system is rubbish now (in NSW anyway). I suppose the recent large increases in power cost would mean a shorter return time though.

As bushmiller said, subsidies of any kind distort the market.

Think back to the LPG installation subsidy, almost overnight the cost of LPG installations increased by the same amount as the subsidy, as the subsidy reduced, the cost of installation reduced by the same amount. To add insult to injury the government then decided to recoup these subsidies by increasing the excise on LPG, which of course affected every user of automotive LPG, not only the ones that "benefited" from the subsidy.

First home owner grants are another prime example, I could go on.

Subsidies are used by governments (of any colour) for political gain, but ultimately it totally distorts the market and all consumers and tax payers finish up paying more than the subsidies ever put in the pockets of the recipients (usually the industry - not the consumer it was aimed at).

Economics 101.