Energy Return on Investment
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The real question is whether the solar panel on a garage roof would generate sufficient power to manufacture its own replacement. Free spirit will answer, "yes, provided you ignore very large sections of its supply chain".
While Free Spirit may debate whether it powers its own replacement, he certainly can't debate whether it can power a car on any surplus after allowing for its own replacement.
SpineyNorman
Inappropriate content removed
I'd rather hear from free spirit if it's all the same - you seem to be very blinkered on this stuff and although I've found your posts informative you appear to be incapable of taking onboard, or even engaging with, anything that contradicts your catastrophist outlook.
"What is the Minimum EROI that a Sustainable Society Must Have?" (Hall 2008) is very clearly written and addresses the usual misconceptions. The answer is that a ratio of 3:1 might allow a civilisation of sorts to function, but would leave no discretionary surplus for all the things we value about civilization: art, medicine, education, etc.
Well that's the laws of physics for you, I suppose.
bi0boy
Power User
It's simply saying that when calculating EROI one should take into account the cost of making the energy available at the point of use. School kid stuff basically. Where is the proper research integrating environmental and societal impact?
Indeed. But apparently sufficiently unintuitive as to cause a very large number of people to imagine that 7 billion people and an industrial civilisation can be sustained through the conversion of tanning studio emissions. Interestingly, the school kids I talk to get it, which more or less supports your point, if not in the way you intended.
That would be in the "environmental and societal impact" research paper. Are you suggesting that no paper is complete or useful unless it addresses your areas of interest?
An equivalent 50mpg car needs 5000 gallons of petrol to drive 250,000 miles. Cost at £3 per gallon = £15,000.
A 5kw solar PV system costs approx. £7000 to install.
In this example, using cost as a rough guide, the EROI of Solar PV is double that of Oil.
bi0boy
Power User
What? I think most people understand that energy sources requiring more energy input than they produce of output are of limited use. You don't have to hold any views as to the sustainability of civilisation to agree with that.
Where's that to then? I'm suggesting it's no more useful than a research paper on solar panels concluding that not only should they ideally be pointed towards the sun most of the time, but that they tend to produce less energy when sited in regions with a cloudy climate.
Hall & Klitgaard (Springer, 2012) - Energy and the Wealth of Nations
free spirit
more tea vicar?
No, I'd answer yes if reasonably well situated, it can over it's first few years of operation cover both it's direct energy costs, and the proportion of the energy costs that should fairly be allocated to it for replacing the rest of the supply chain over time, and still have a significant amount of generation to contribute to powering the rest of society.
It's true that there is a significant up front energy investment required that for each panel will take maybe 3-5 years to payback, but then the majority of those panels should still be functional for well over 50 years, quite possibly a lot longer in many cases, albeit with performance degrading slightly year on year (around 0.3-0.5% per year output reduction seems to be what's coming out of the long term tests for quality panels).
Most EROI calculations come up with something in the region of 8:1 EROEI for solar PV, but they mostly use 25 years as the lifespan. If you use 50 years as the lifespan, which is realistic IMO, then it's going to be more like 10-15:1 EROEI (allowing for reductions in output, and a replacement inverter)
In this respect the energy payback situation is relatively similar to Hydro - even more so if it turns out, as I suspect, that a lot of the panels are still in use in 100 years time.
fwiw, this is a 30 year old PV panel that's been in continuous use outside for since 1980, and according to the owners tests, is still kicking out roughly it's original specified output - actually it was kicking out more than it's rated output in the test probably due to the cold panel temperature, and maybe higher than 1000W/m2 solar input.
The backsheet is yellowing a bit, but other than that it looks in reasonable condition.
free spirit
more tea vicar?
I'm not surprised, I'm sure you can put together a really plausible presentation for school kids on this subject.
It does seem though that the greater the depth of knowledge someone has about the subject, the less they'll agree with all of your analysis on it.
free spirit
more tea vicar?
ps In the UK, we've just passed the 2GWp mark for installed capacity, with apparently 0.5GWp being installed in this quarter alone, mostly on solar farms rushing to get installed before a reduction in the ROCs rate they get paid, and most of the smaller scale side of the industry still relatively idling, so I reckon we probably have the capacity now to be installing at around 1GWp per quarter in peak summer months, or maybe 2-3 GWp a year between the ground mount and roof mounted segments, if government and EU policies would give us the clear framework to get on and do it.
That's around the equivalent of a 1GW nuclear power station that we as an industry could install every 2-3 years as of right now given the right policy framework, with Germany currently installing around 8GWp per year, which is around an equivalence to a 1 GW nuclear power station being installed per year in terms of the annual energy output from both.
Globally we're at just under 30GWp being installed a year now, expected to double over the next 5 years with particularly strong new demand growth expected from China and Japan, with actual manufacturing capacity already in excess of 45GWp per year if there was the market for it.
These are not small numbers, and in much of the world solar PV is already price competitive with at least the consumer price paid for electricity. We're talking here about the equivalent of 3-4 1GW new coal, gas, nuclear power stations being installed a year globally, and that's at the point where it's only just about becoming price competitive. Once it becomes fully price competitive without subsidy, which isn't far off now at all, then there should be huge market growth in areas of the world that aren't able or willing to offer the sort of kick start subsidies Europe in particular has been funding to get us to this stage.
There have been and remain some massive challenges in the global PV market, not least of which is the current EU anti-dumping madness that's seen the EU announce that they might impose a retrospective punitive import duty on any Chinese panels imported into the EU after 6th March just gone, but won't make the final decision on that until later in the year... as a ridiculously counterproductive response to accusations the Chinese are dumping panels on to the EU market and unfairly propping up their manufacturers to undercut EU manufacturers (aka Solarworld of Germany)... ignoring the fact that the reason for the recent massive price reductions is that the global manufacturers expanded their capacity between 2010-12 following a 160% increase in the EU solar market in 2010, only to find that austerity policies across the EU had resulted in the market only expanding at 5% per year in 2011 and 12, so there was massive oversupply globally, resulting in huge price reductions as manufacturers tried to keep the volumes up to stay in business... so it was really European policy decisions that caused the problem in the first place.
The nuts thing about decisions like the drastic 75% Feed In Tariff cuts we endured in this country last year is that the UK solar industry would have contributed far more in tax and reduced benefit payments to government coffers last year without these cuts than the Feed In Tariff subsidies would have cost the UK public, so in the short term a better managed staged reduction in FIT rates would have resulted in higher tax revenues, lower unemployment costs, and barely noticeable changes to energy bills.
I reckon in the UK that the combination of various government fuck ups in schemes to support solar PV, solar thermal, heat pumps, biomass, and insulation has probably cost somewhere between 50,000-100,000 full time jobs directly and indirectly in the last 12-18 months, which is a ridiculous state of affairs at this crucial point in history when both the jobs and the resulting energy savings / increased renewable generation is so desperately needed.
That's around the equivalent of a 1GW nuclear power station that we as an industry could install every 2-3 years as of right now given the right policy framework, with Germany currently installing around 8GWp per year, which is around an equivalence to a 1 GW nuclear power station being installed per year in terms of the annual energy output from both.
Globally we're at just under 30GWp being installed a year now, expected to double over the next 5 years with particularly strong new demand growth expected from China and Japan, with actual manufacturing capacity already in excess of 45GWp per year if there was the market for it.
These are not small numbers, and in much of the world solar PV is already price competitive with at least the consumer price paid for electricity. We're talking here about the equivalent of 3-4 1GW new coal, gas, nuclear power stations being installed a year globally, and that's at the point where it's only just about becoming price competitive. Once it becomes fully price competitive without subsidy, which isn't far off now at all, then there should be huge market growth in areas of the world that aren't able or willing to offer the sort of kick start subsidies Europe in particular has been funding to get us to this stage.
There have been and remain some massive challenges in the global PV market, not least of which is the current EU anti-dumping madness that's seen the EU announce that they might impose a retrospective punitive import duty on any Chinese panels imported into the EU after 6th March just gone, but won't make the final decision on that until later in the year... as a ridiculously counterproductive response to accusations the Chinese are dumping panels on to the EU market and unfairly propping up their manufacturers to undercut EU manufacturers (aka Solarworld of Germany)... ignoring the fact that the reason for the recent massive price reductions is that the global manufacturers expanded their capacity between 2010-12 following a 160% increase in the EU solar market in 2010, only to find that austerity policies across the EU had resulted in the market only expanding at 5% per year in 2011 and 12, so there was massive oversupply globally, resulting in huge price reductions as manufacturers tried to keep the volumes up to stay in business... so it was really European policy decisions that caused the problem in the first place.
The nuts thing about decisions like the drastic 75% Feed In Tariff cuts we endured in this country last year is that the UK solar industry would have contributed far more in tax and reduced benefit payments to government coffers last year without these cuts than the Feed In Tariff subsidies would have cost the UK public, so in the short term a better managed staged reduction in FIT rates would have resulted in higher tax revenues, lower unemployment costs, and barely noticeable changes to energy bills.
I reckon in the UK that the combination of various government fuck ups in schemes to support solar PV, solar thermal, heat pumps, biomass, and insulation has probably cost somewhere between 50,000-100,000 full time jobs directly and indirectly in the last 12-18 months, which is a ridiculous state of affairs at this crucial point in history when both the jobs and the resulting energy savings / increased renewable generation is so desperately needed.
free spirit
more tea vicar?
yeah... the key point there would be that this study relates to the authors experience working on one of the worlds first 1MW scale solar farms in 2006, with energy inputs including flying experts in to help from around the world, and building a road to the site. The picture also shows a tracker based system, which uses around 20 tonnes of concrete per tracker, for a 20-30% increase in yield, which I'm not really sure works well on the EROEI front either, but isn't being used that much any more.
In fact, I'd expect the road was needed to bring he concrete bases in for the trackers.
Either way, if a road we needed, then I'd just be using temporary trackway, but mostly it's not AFAIK, an it'd be pretty rare for anyone to need to fly in experts these days.
I'm intrigued why they felt the need to release a study on this 6 years after that build, but it does make me think that maybe the author hasn't had much involvement with the industry since then.
FWIW, the reduction in the rates of subsidy have helped to drive down costs and increase efficiencies, which means cutting out a lot of the wasteful energy aspects of the installs, such as using pile driven posts rather than concrete blocks for each post, not building maintenance roads as they're not needed etc.
And I'm not sure where one of the 'experts' quoted in the article gets his info from, but the 'cheap panels' used in farm scale installs are virtually all poly crystalline panels, which are in general around 50-70% of the energy input of Mono panels, it's part of the reason they're cheaper to produce ffs.
Looks like we might be sub-contracting on some of these big solar farm jobs later this year, so I'll be sure to report back on the amount of road building I see going on on site.
elbows
Well-Known Member
Its still not clear to me that hardly anyone is prepared to shift their assumptions at this point, no matter the data or studies. I think we'll be waiting a bit longer, perhaps a lot longer. Personally I expect the worst but do not rule out the possibility of the picture at least remaining somewhat mixed for years to come. In some ways this bothers me, e.g. in terms of how dramatic the eventual correction to peoples expectations will be. On the otherhand at least we cannot be said to be giving up prematurely.
By the way I finally got round to seeing some of the old nuclear war drama Threads the other day. The resulting primitivism dramatised in the latter part of it reminded me of some of the arguments about our energy future on this forum. Threads suffered from the same funny mix that almost inevitably comes with topics that involve the end of a way of life - perhaps useful for thinking the 'unthinkable', and necessarily shocking, but still hard to watch it with a straight face. Mostly due to some absurdly simplified assumptions about quite how the surviving humans will cope with their plight, and how many fronts they will rapidly regress on.
By the way I finally got round to seeing some of the old nuclear war drama Threads the other day. The resulting primitivism dramatised in the latter part of it reminded me of some of the arguments about our energy future on this forum. Threads suffered from the same funny mix that almost inevitably comes with topics that involve the end of a way of life - perhaps useful for thinking the 'unthinkable', and necessarily shocking, but still hard to watch it with a straight face. Mostly due to some absurdly simplified assumptions about quite how the surviving humans will cope with their plight, and how many fronts they will rapidly regress on.
Just so we are clear about the magnitude and complexity of "the supply chain" - the "supply chain" stretches from the ball bearing in the truck that mines the gypsum for the bricks for the factory that makes the oxygen for the smelter, right through to the hydrocarbon powered industrial agriculture facility that makes the protein in the solar installer's sandwich.
For connoisseur of this kind of nonsense, the key phrase I've bolded is lethal. Here's how it works.
1. Solar is, by many accounts, the least unsatisfactory substitute for hydrocarbon (the numbers vary, depending on how much of the candidate substitute's supply chain is ignored in its EROEI calculation, but solar is regarded as capable at least of exceeding unity).
2. So, in meeting a given power demand, a basket of substitute technologies has a lower aggregate EROEI than meeting the demand purely by solar.
3. So if solar can't power the global industrial manufacturing system it is the product of, nothing can. i.e. any other combination will perform worse than solar alone. (I am not talking about hoping the wind blows when the sun isn't shining, I'm talking about intrinsic EROEI).
Then to rephrase Free Spirit: "Provided the technologies that are worse than mine can power the fraction of the global industrial manufacturing supply chain not accounted for by my demand, my demand is sustainable."
They can't. So his isn't.
Again, connoisseurs: note the use of the word "big" in relation to that fraction of power demand currently supplied by solar.
Argument: current toy sized projects can be maintained using existing infrastructure. Therefore full scale (i.e. country sized) projects can be maintained without access and transportation infrastructure after the current infrastructure has degraded.
Also note the "we". This is not an unbiassed view point. As Upton Sinclair said, "It is difficult to get a man to understand something, when his salary depends upon his not understanding it".
The big problem with these EROI studies is that they are only useful when applied to fuel sources with a finite and diminishing supply. As in individual an oil well or field.
The author of the above report, Mr Hall, is a biologist who tries to apply studies of animal populations to economics. His theories are not accepted as valid by economists.
Some of the problems with EROI are explored in this study
http://www.sciencedirect.com/science/article/pii/S0301421512002133#BBIB38
Economics is formally indistinguishable from pseudo science. Economics, in its current form, consist of a series of unverifiable propositions about the physical world which would have to be true for it also to be true that economic expansion is not limited by resource scarcity.
They make such propositions on the basis of statements about the physical world which are an embarrassment to anyone with a passing familiarity with the physical sciences (I speak as someone qualified in both).
Hall merely points that out. Of course his theories are not accepted as valid by economists.
Your reference, by the way, falls into the classic trap of proceeding from "Assume the existence of a global, industrial manufacturing system. In this study … etc." to a set of conclusions which are irrelevant because the assumption is not warranted.
It also fails on the fundamental point that, in addition to making a statement about EROEI which at best betrays a fundamental lack of understanding about what it measures, fails to note that, while the energy source may be theoretically inexhaustible, the resources required by the apparatus necessary for its capture, upgrade, transportation and end use most certainly are not and must be accounted for in any estimate of EROEI.
The main component of solar pv is silicon, the second most abundant element on the planet.
Not sure how this qualifies as a 'limited supply'.
The other main elements used in solar pv are aluminium and copper, both can be recycled.
The existing fossil fuel infrastructure is being replaced by renewables. The process is going to take a couple of decades.
You seem to think renewable energy must exist entirely separate to the rest of society. Why?
Think about the coal powered rail network. That was built by men with shovels with the help of horses for transport, over the course of many years.
Not sure how this qualifies as a 'limited supply'.
The other main elements used in solar pv are aluminium and copper, both can be recycled.
The existing fossil fuel infrastructure is being replaced by renewables. The process is going to take a couple of decades.
You seem to think renewable energy must exist entirely separate to the rest of society. Why?
Think about the coal powered rail network. That was built by men with shovels with the help of horses for transport, over the course of many years.
free spirit
more tea vicar?
yeah - all of which is already included within the energy required to keep the country running, it can't and shouldn't be specifically allocated to solar PV in the EROI calcs, as should be obvious to anyone with half a clue about the subject. This is to say that roads and infrastructure of this country that already exist would need to be maintained with or without solar PV installations, the energy input from solar PV is therefore a net contributor to the energy required to maintain this infrastructure and other purposes... actually I doubt it'll have much direct impact on road building, but could do by replacing oil for energy generation or heating, which would then be available for the road maintenance.
You continually act as if solar PV has to be able to power everything by itself to be worthwhile. It doesn't.
1GWp being installed a year is a little above toy scale, and that's the level we've achieve after just 3 years of serious investment in the industry, and the industry has the capacity to roughly double every year to 18 months with the right policy framework in place.
yeah well, if you were being fair you'd have to note that my viewpoint was the same before my salary depended upon it, I just now have a lot more expertise and experience in the industry to back that viewpoint up.
free spirit
more tea vicar?
But what proportion of the ballbearing should be allocated to solar PV? What proportion of the output of that brick making factory is to be used in the solar PV supply chain?
These figures are already included proportionally within the embeded energy figures for each material input that's used with a LCA for a solar PV module. It's not necessary for anyone doing a LCA of solar PV to then also do a LCA of every single element of the supply chain below it, because those figures are already usually available from previous work someone else has done. If this were not the case then it would be virtually impossible to work up a LCA for any product as you'd have to go back through the entire supply chain every single time in the way that you continually tie yourself up in knots over.
I wish you'd get your head around this as it's really boring having the same conversation again and again to explain what should be a pretty basic concept for someone who's apparently got 2 masters degrees in related fields.
If you'd actually looked into this in detail as well, then you'd realise just how small a part of the embeded energy costs of a panel you're arguing about. For example a fairly small aluminimum smelting plant such as Fort William, produces 40,000 tonnes of aluminium a year, and has been operating for over a century. So there's maybe 4 million tonnes of aluminium produced so far from that plant, a plant that's powered via an 85MW hydro power plant... so what proportion of the embeded energy do we think would be represented by the embeded energy contained in the buildings themselves vs the actual direct energy used to directly smelt those 4 million tonnes of Aluminium at around 85MW peak operating power input (and I believe this power input actually includes most of the power supply to the workers homes, or at least it did on initial commissioning)?
I'm not going to work out the figures, but it's obviously an absolutely tiny proportion, and most of the stuff you mention would also represent absolutely tiny proportions of the total energy input to each individual panel, so even if the estimates used weren't particularly accurate, it would still be unlikely to make anything like eve 1% difference to the actual figures for each panel.
You'll also hopefully have noted the fact that that plant has been successfully running from hydro power for nearly a century.
wtf are you on about now?
hydro, tidal, tidal stream, wind should all have better EROI than solar if located in suitable locations. As I'd expect would biomass and biogas, and energy from waste though these are all subject to the thermal inefficiencies that coal, gas and oil are - a point that gets repeatedly missed in these discussions, where people conveniently ignore the 60% thermal losses from coal generated electricity when pointing at coal's high EROI figure for thermal use, not electricity generation.
free spirit
more tea vicar?
are you saying that the current global industrial manufacturing system doesn't in fact actually exist and is merely a figment of our imagination then?
or do you just need to conveniently ignore its existence in order to justify your position?
Personally I like to start from the situation we're in now and work from there, rather than some fictitious situation.
I'd love to see Falcon's recipe for baking a cake...
Add flour, then add more flour, then add more flour, then add more flour, then put it in the oven.
if you find that the cake isn't up to scratch, then assume that it's impossible to bake a cake using flour, and flour is useless as an ingredient and must be disregarded in favor of an oil based substitute that can give you the same energy value of a proper cake with just one ingredient, and since oil is running out we're just going to have to get used to not eating cake anymore.
I'm saying the global industrial manufacturing system very definitely exists.
I'm saying that, without a functioning global industrial manufacturing system, which extends to the food supply for its workers, your technology cannot exist.
I'm saying that, because of its complexity, the global industrial manufacturing system requires an energy source of an EROEI > 50 to function (EROEI is a function of complexity) - currently supplied by hydrocarbon. The statement that it can function with lower EROEI energy sources is at best untested and in fact implausible.
I'm saying that there are no renewable energy sources even theoretically capable of providing the minimum EROEI required to maintain the complexity of the industrial manufacturing system.
I'm therefore saying your question about which bit of the global industrial manufacturing system your toys should be allocated to post-hydrocarbon is meaningless, as it presumes there will be one post-hydrocarbon, when there won't.
We know the first step of yours. "Assume the existence of an oven".
SaskiaJayne
Rural Guerrilla
Something I've always wondered. How long would one of those wind generators standing in the sea off Clacton have to run for to generate the power used by the total amount of fossil fuel used to manufacture/transport/erect & to get that windmill up & running. I would have thought that until windmill has 'repaid' the energy used to get it to the stage where it is generating power it cannot be said that it is producing 'green' energy. I guess the same question could be asked about solar farms or even just solar panels on a house roof.
& is this even a relevant question, I'm not really sure?
& is this even a relevant question, I'm not really sure?
free spirit
more tea vicar?
And I don't disagree with you on that, the mix of all energy forms available combined needs to be capable of supplying the energy needs of that extended global industrial manufacturing system.
PV alone does not need to be capable of supplying it all by itself in order to be an important and useful contributing part of that energy mix.
Out of all the statements you've ever come out with, that must rank among the least supportable of them.
If that were the case then an industrial society based largely on electricity from 30-40% thermally efficient generators would have been completely impossible as it involves throwing away 60-70% of the energy content of the fuel vs 2% of energy used in extraction at 50:1, 5% at 20:! or 12.5% at 8:1 EROEI.
The efficiency of conversion should logically have a far greater impact on the economic value of that fuel to the economy than any difference in EROEI figures from about 8:! upwards.
These 2 factors are entirely intertwined, yet you never address the efficiency of generation of electricity, or consumption of energy - why is that?
But you base this on a completely false premise.
Why would I assume there wasn't an oven when I can clearly see that there is an oven that's in full working order?
You've developed a theory of how everything works that is so divorced from reality that to make it work you have to assume that the entire industrial infrastructure doesn't already exist and must be built from scratch entirely powered by each renewable energy source alone for those renewables to have any viability.
The reality is that we're transitioning from one energy mix to another, and at the same time we're getting much more efficient in our utilisation of that energy.
Renewables also can not be compared directly with fossil fuels in EROEI terms without taking account of the fact that the energy they generate directly is high grade electrical energy, vs fossil fuels which might have a higher EROEI for thermal purposes, but that need to be burnt in 30-60% thermally efficient power stations to generate that electricity, or in 30-40% efficient internal combustion engines to power vehicles.
Basically your entire theory is built on completely false foundations that ignore entirely the way that energy is actually used once it's pumped from the ground, or absorbed and transformed from sunlight, focusing instead on only one method of analysing one narrow part of the picture.
Indeed, renewables in Germany have reduced the cost of wholesale electricity for industrial use during the working day to such an extent that companies running fossil fuel power generators are crying foul. A fine turnup for the books
free spirit
more tea vicar?
TBF the market is distorted by the subsidies, which will be correcting itself over the coming years as the level of subsidy is now massively reduced, but yes there can be lots of energy available for industry in the middle of the day when it needs it most.Indeed, renewables in Germany have reduced the cost of wholesale electricity for industrial use during the working day to such an extent that companies running fossil fuel power generators are crying foul. A fine turnup for the books
I believe that the industrial minnow that is Germany was at 50% of it's electricity supply being from wind and solar combined for a good part of the middle of the day today. Not bad for some toys eh.
I understood that the pricing structure favours power generators with lower marginal cost, and solar has none. (compared to fossil fuels where you have to pay for the fuel, to make that really clear...)
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