[Graeme]

Solar, peak oil and net energy

Importantly, it takes energy and capital to drill oil wells, build power stations and erect wind turbines. The ratio of the useful energy produced relative to the energy invested to get that energy is known as the energy-return-on-investment, EROI, or sometimes ‘net energy’. It is the energy surpluses fossil fuels make available that have enabled the development of the modern state, with its advanced education, healthcare, welfare, and the richness and diversity of modern life.

But what if global net energy is on a downward trend? The EROI of the global oil supply is currently taken at between 10:1 and 18:1, and declining. Capital investment for the oil industry has tripled in the past 10 years, but production has plateaued. Oil supply is increasingly reliant on deepwater drilling, enhanced recovery and unconventional oil.

If we take the commonly quoted net energy figures for solar of somewhere between 10:1 up to 60:1—and still increasing—we might assume that PV (photovoltaic solar) is an irresistible ‘disruptive technology’ on an assured upward trajectory. However, it’s not at all obvious that solar provides the same value to society as oil and other energy sources; every one of the more than a million grid-connected PV systems in Australia could be turned off for a week and few would notice, nor would the electricity system reserve margins be adversely affected. Yet even minor disruptions to petrol supplies, natural gas or the internet can have a major effect on daily life. The curious thing is that the literature on the solar life cycle seems to readily accept these high numbers without probing what they really mean.

abc

[Graeme]

Mods, Can this post be moved to this thread?

[sunweb]

New scientific studies show it takes years to payback the energy used in solar electric devices. EROI (Energy Returned on Energy Invested) says it takes energy – mining, drilling, refining, transporting, installing, maintenance, and replacement parts – to make the devices necessary to capture solar energy.
Spain’s Photovoltaic Revolution: The Energy Return on Investment by Prieto, Pedro A., Hall, Charles 2013.
http://www.springer.com/energy/renewabl ... 419-9436-3
and http://energyskeptic.com/2013/tilting-a ... -solar-pv/
also
Energy in Australia: Peak Oil, Solar Power, and Asia’s Economic Growth
By Graham Palmer. 2014. SpringerBriefs.

Spain’s Photovoltaic Revolution presents the first complete energy analysis of a large-scale, real-world deployment of photovoltaic (PV) collection systems representing 3.5 GW of installed, grid-connected solar plants in Spain. Prieto and Hall conclude that the EROI of solar photovoltaic is only 2.45, very low despite Spain’s ideal sunny climate. Germany’s EROI is probably 20 to 33% less (1.6 to 2), due to less sunlight and efficient rooftop installations.

“Solar advocates can learn from this analysis . . . “ Not looking at the reality of EROI “is not good science and leads to wasted money and energy that could have been better spent preparing more wisely for declining fossil fuels in the future.”

This study does not detail the environmental destructive mining, toxic chemicals or air and water pollution necessary to get the materials for manufacturing and installing solar devices. It is the sun not the devices that is renewable, green and sustainable.

Sometimes the truth doesn’t set you free; it simply creates denial for short-term fun or profit.

Invest in solar now while we still have the fossil fuels from fracking, deep water drilling, Canadian tar sands and mountain top removal for coal. Then we can have the massive trucks, large refineries, huge manufacturing facilities for glass, aluminum, copper, and photovoltaic cells that are necessary for these high tech, temporary solutions. Don’t let true science or concern about the earth’s future stand in your way.
http://sunweber.blogspot.com/2014/02/so ... sting.html

[Ulenspiegel]

It is poor performance to post the same nonsense again and again.

Data from last year showed that rooftop PV installations have an energetical pay-back time of less than two years in Germany, that with monocrystalline modules, i.e. it is the worst case scenario.

This means that the EROEI is at least 10, more likely 20 as the oldest German PV installation is around 40 years old and still works with more than 85%.

[Longtimber]

http://www.renewableenergyworld.com/rea ... uly23-2014

Missing the point as you free from the grid, PV Energy is cheap, Storage not, so we size the PV for the 6pm loads, which leaves 300% surplus much of the day. You have to come up with innovative ways to use the power. Hot water / ice.

[sunweb]

Ulenspiegel - and your reference is? URL. Research paper? Independent research?
Try this one: Germany not an example
http://notrickszone.com/2014/04/27/ange ... hancellor-
stuns-declares-germanys-energiewende-to-be-on-the-verge-of-failure/

[GHung]

I'm more on Longtimber's page, but I suppose it depends on your worldview. Those who are arguing whether or not renewables, specifically PV, will affect the human experiment much are barking up a dying tree, IMO. No single technology, indeed, technological solutions as a whole, won't alter the course that humans have taken much. We're too far along the path of depletion for that. Faustian bargains, all.

Many adopters of PV and other renewables see the role of these technological 'solutions' in a different light, with no delusions that they will ''save mankind and the planet''. 'Soft landing', reduced reliance on complex, top-down systems, reduced ongoing support of corrupt corptocracies,,, I can think of many reasons to adopt and promote renewables now that don't include some altruistic, idealogical goal of saving humanity's future and the environment. Not being a mindless gridweenie promotes a way of thinking that carries over into other aspects of life; very much a case of recognizing problems even while acknowledging few of them have perfect solutions, or any solutions at all.

Meanwhile, Sun Electronics has grade A listed panels for 64 cents/watt by the pallet, or 69 cents/watt per panel. You can't smoke'em if you ain't got'em.

I can hear our water pump humming away, moving water up to the ridge tank, just as it's been doing for over 15 years; same pump, same panel. I'm pretty pleased with that.

[kublikhan]

Sunweb, Prieto and Hall's book is not the end all be all of "True Science". There are plenty of "True Science" studies out there that disagree with their numbers. Surf wrote up a rebuttal last time someone linked to this:

EROEI is nothing more than watts in to make it and the Watts it produces. Anything that is not required to produce energy should not be included.
...
Security cameras and electric alarms do consume a small amount of electricity. The 138.6 GW?H/Year factor he applies for security is in my opinion simply ridiculously large.
...
Premature phase out??? Since when does Obsolescence effect the power generation or power required to make something. If a piece of equipment is obsolete but still works and is still being used it will not effect EROEI. And again the 148.4 GWh/year factor is way too big.
...
All of this section is not an energy cost or necessary energy expenditure. They are simply optional financial cost. As far as I know there is no mathematical formula that links dollars to watts. Without such a link dollars spent cannot be considered a watt in or watt out.

Prieto and Hall EROEI calculations have come up before on Peakoil.com. Basically they make one massive mistake in there analysis. They assume Dollars = Watts. It does not. Some people get paid a lot of money for sitting at a desk and doing nothing (or nearly nothing) Others get paid little but do a lot of work. Since most of the cost for anything is the money spent to pay workers, assuming Dollar = watts is simply wrong.

A good EROEI excludes labor. Then electricity, oil, and gas (all in watts or BTUs) is used to make it is totaled up to generate the energy in number. And then all the watts or BTUs of electricity , oil, and gas produced is totaled to generate the energy out number. And then finally the Energy out is divided by energy in to great the EROEI number.

The vast majority of researchers do it right and generate numbers significantly higher than the 2.45 EROEI number Preto and Hall came up with.

And if you wanted to look at one of those "True Science" studies, here you go:

Abstract:
A high energy return on energy investment (EROI) of an energy production process is crucial to its long-term viability. The EROI of conventional thermal electricity from fossil fuels has been viewed as being much higher than those of renewable energy life-cycles, and specifically of photovoltaics (PVs). We show that this is largely a misconception fostered by the use of outdated data and, often, a lack of consistency among calculation methods. We hereby present a thorough review of the methodology, discuss methodological variations and present updated EROI values for a range of modern PV systems, in comparison to conventional fossil-fuel based electricity life-cycles.

Conclusions
Improvements in PV technologies over the last decade have brought about notable increases in their EROI. When calculated in terms of the electricity output per unit of primary energy invested (Eqn. 2), The EROIel of PV ranges from 6 to 12, which makes it directly comparable to that of conventional thermal electricity without CCS.

When instead calculated according to the often employed formula EROIPE-eq =T/EPBT (Eqn. 4), i.e. expressing the energy ‘returned’ by PV in terms of its ‘Primary Energy equivalent’, the EROI of PV is up to 19 to 38, which puts it squarely in the same range of EROI as conventional fossil fuels.

These new results prove that PV is already a viable energy option that may effectively contribute to supporting our societal metabolism, while significantly reducing the depletion of the remaining stocks of non-renewable (fossil) primary energy, and mitigating the concurrent environmental impacts in terms of global warming and polluting emissions.

However, even these remarkable results should not allow one to forget that PV, like all other renewable technologies, must still be supported by an initial investment of primary energy, which is, as of today, of fossil origin. We therefore argue that available monetary and energy resources should be funnelled in the right direction without delay, lest not enough high-EROI fossil fuels are left to support demand during times of gradual shift to renewable resources.

Authors:
Marco Raugei*1,2, Pere Fullana-i-Palmer1 and Vasilis Fthenakis2,3
1 UNESCO Chair in Life Cycle and Climate Change, Escola Superior de Comerç Internacional (ESCI) – Universitat Pompeu Fabra, 08003 Barcelona, Spain
2 Center for Life Cycle Analysis, Columbia University, New York, NY 10027, USA
3 National Photovoltaic Environmental Research Center, Brookhaven National Laboratory, Upton, NY 11973, USA

The energy return on energy investment (EROI) of photovoltaics: Methodology and comparisons with fossil fuel life cycles.

[kublikhan]

Longtimber, It's not quite as cut and dry as that. Solar PV is not sized for peak loads. Rapid response fossil fueled peaker plants handle the increased demand of the peak loads.

The article you linked to says the real problem is not a technical problem, it's a profit problem: distributed solar PV displaces fossil fueled demand(and the utility's profits):

Utilities point to the duck chart as evidence that renewable energy development should be stopped on technical grounds. But it’s in the belly of the beast we find the real utility problem: energy demand displaced by solar represents lost market share for utilities as their customers switch to sunshine.

To paraphrase Mark Ferron, recently retired from the California Public Utilities Commission: it’s open season on the utility’s duck.

Also, the power grid is changing to include demand response and other measures to help alleviate the stress of adding variable renewables into the grid. Here is more from the Department of Energy:

Demand response provides an opportunity for consumers to play a significant role in the operation of the electric grid by reducing or shifting their electricity usage during peak periods in response to time-based rates or other forms of financial incentives. Demand response programs are being used by electric system planners and operators as resource options for balancing supply and demand. Such programs can lower the cost of electricity in wholesale markets, and in turn, lead to lower retail rates. Methods of engaging customers in demand response efforts include offering time-based rates such as time-of-use pricing, critical peak pricing, variable peak pricing, real time pricing, and critical peak rebates. It also includes direct load control programs which provide the ability for power companies to cycle air conditioners and water heaters on and off during periods of peak demand in exchange for a financial incentive and lower electric bills.

The electric power industry considers demand response programs as an increasingly valuable resource option whose capabilities and potential impacts are expanded by grid modernization efforts. For example, sensors can perceive peak load problems and utilize automatic switching to divert or reduce power in strategic places, removing the chance of overload and the resulting power failure. Advanced metering infrastructure expands the range of time-based rate programs that can be offered to consumers and smart customer systems such as in-home displays or home-area-networks can make it easier for consumers to changes their behavior and reduce peak period consumption from information on their power consumption and costs. These programs also have the potential to help electricity providers save money through reductions in peak demand and the ability to defer construction of new power plants and power delivery systems -- specifically, those reserved for use during peak times.

One of the goals of the Smart Grid R&D Program is to develop grid modernization technologies, tools, and techniques for demand response and help the power industry design, test, and demonstrate integrated, national electric/communication/information infrastructures with the ability to dynamically optimize grid operations and resources and incorporate demand response and consumer participation.

Demand Response

[Graeme]

K, Great post. Thanks. Here's another on wind. Also cost for battery storage for EV's is coming down too. Solar PV will become more efficient too.

[KaiserJeep]

OK, I read the above and the words made sense but it flies in the face of actual experience.

I live in Silicon Valley, an area with Smart Grid fully implemented, we all have SmartMeters that rat out our consumption patterns to the power company. A significant number of us have solar PV on our residence roofs, and public high schools and shopping malls have solar pavilions to park under. Basically we have solar PV capacity that today exceeds the peak power demand which around here is early afternoon A/C demands. (Baseline power demands are met primarily with Natural Gas-fired diesel and secondly with some nuclear power.)(Hydropower is way down due to the drought.)

The matchup with distributed solar and distributed peak demand is spectacularly successful. By which I mean I live less than 2 miles from a CALPINE peaking power plant that uses natural gas fired turbines for power generation. The plant is less than 10 years old and very clean, the only way to tell when it is operating is to look for the water vapor plumes from the stacks.

CALPINE is losing money today and will probably shut the NG peaking plant down. Even with the influx of legal and illegal immigrants, the growth in solar PV generating capacity has outstripped the growth in power demand. The NG plant is rarely online any more.

[sunweb]

kublikhan - I have sent the ERoEI info on to Charles Hall and Pedro Pieto for their response if they have the time.

ERoEI is only a part of the restraints on solar. As your report says, "However, even these remarkable results should not allow one to forget that PV, like all other renewable technologies, must still be supported by an initial investment of primary energy, which is, as of today, of fossil origin."
Energy Return on Energy Invested (ERoEI) is a part of the equation. There is also a massive infrastructure of mining, processing, manufacturing, fabricating, installation, transportation and the associated environmental assaults. Each of these processes and machines may only add a miniscule amount of energy to the final component of solar or wind devices. There would be no devices with out this infrastructure.
I have a picture of the robot arms making solar panels in a production line. The immediate energy contribution of the these robots may be miniscule but the system behind it before it ever gets to the factory certainly isn't.

I have a picture of a 4 story dump truck for copper mining. This diesel/electric machine uses 1 gallon every 30 seconds 24/7. The scoop filling the truck dwarfs the truck. Doing that with solar and/or wind? This is only one of the many natural resources necessary.

My internal fan on my inverter for my 3kWh grid-tie system went out last year. (As an aside, I put up my first panels on a ZoomWorks tracker in 1983 using the old massive used telephone batteries for storage). The system can't work with out this small fan. Again, there is a whole fossil fuel supported infrastructure behind this small fan.

And after you make the panels, the support electronics and equipment will you have enough energy available to make the repairs?, replace damaged panels? replace panels in old age? and make all the things you want the panels for? water pump? hair dryer? Without the fossil fuel support infrastructure?
There simply would be no "renewables" without fossil fuels. They are at best a transition energy, but worse they are a false hope.
I know I going to catch hell for this.
http://sunweber.blogspot.com/2011/12/ma ... aking.html
http://sunweber.blogspot.com/2011/10/to ... -bulb.html
and
http://sunweber.blogspot.com/2013/10/a-small-fan.html

[GHung]

sunweb: "They are at best a transition energy, but worse they are a false hope."

You keep repeating this, and I'm waiting for you to propose a better alternative. Life isn't about absolutes or perfect choices; it's about going with the best choices available. It occurs to me that virtually any alternative suffers from at least the same vulnerabilities as PV, most requiring far greater ongoing inputs, more ongoing maintenance, and far more costly decommisioning costs in terms of energy and capital. At least my PV panels aren't going to contaminate my descendants' water supply in a thousand years, long after our generation is forgotten.

If you have a better alternative, I would love to hear about it.
Fans are cheap. Keep spares and hope for the best. I do.

[sunweb]

GHung - there is no alternative to the energy lifestyle we have. That is the problem. Everything proposed is continuing the assault on the only earth we have, the only air we have, the only water we have. Moving the climate towards unlivable if it hasn't gotten their already. Acidifying the oceans. Depleting the ocean fisheries. Poisoning the top soil.

I cut my first cord of wood 40 years ago with a 6 foot saw and an axe. I can tell you, I really liked my chain saw.

The first fencing we put in at our orchard, I hired a friend with a post hole digger on his bobcat. Since, I have dug many posts in by hand. I sure like that bobcat. I actually was out today, digging in a post in a part of my fence that a drunk went through last late fall.

Essentially, what constantly is proposed is some version of more of the same - BAU. Solar would be elegant if it didn't come with all the baggage. I am at 71 probably the last generation to live like a pharoah with many energy slaves. This generation can make the decision not to have resource wars and continue the assault on the environment or it can do what it probably will and leave an earth in pretty rough shape. These decision we are making with so many unknown and unintended consequences is really a moral/ethical one and not an engineering one.
http://sunweber.blogspot.com/2013/11/to-die-for.html

I will take the advice given above, I have said my piece here as noted more than once so guys and gals go for it.

We will do anything and everything to maintain our present personal level of energy use and the comfort it affords us. We will do anything and everything to the earth, to other people and even to ourselves to continue on this path. And if we don’t have the energy level we see others have, we will do anything and everything to the earth, to other people and even to ourselves to attain that level. The proof of this assertion is simple; we are doing it.

[vtsnowedin]

Energy can't = dollars? Please tell my utility that so they will stop charging me 22 cents per KWH.
Why isn't the cost of something installed in dollars a good proxy for how much energy it took to make it, transport it, and install it? Say that fan costs $100 installed. Is it not a good bet that it took no more then 455 KWHs of energy to create it and get it there? It might be less of course, some middle man skimming off a big markup but it certainly won't be any more.

[yellowcanoe]

We will do anything and everything to maintain our present personal level of energy use and the comfort it affords us. We will do anything and everything to the earth, to other people and even to ourselves to continue on this path. And if we don’t have the energy level we see others have, we will do anything and everything to the earth, to other people and even to ourselves to attain that level. The proof of this assertion is simple; we are doing it.

I'd agree that the vast majority of people are trying to maintain their personal level of energy use and the comfort it provides. However, I'd hardly characterize Ghung as being one of those people. Yes, with the pv systems he has put in place and spare components he has collected he is positioned to maintain his current level of energy consumption for hopefully several decades. However his level of energy consumption is far less than what the average person consumes (or would consume if they could afford it). My recollection is that he is running lighting and refrigeration, which are pretty valuable uses of energy. He isn't trying to run things like dish washers and air conditioners. We'd be better positioned for the future if more people could become self sufficient for their most basic energy requirements and greatly reduce their overall energy demands.

[sunweb]

I just received this. I am waiting for a reply from Pedro Prieto. I think I will also ask Graham Palmer in Australia who came up with similar results for a reply.
Charles Hall replies :

For a real energy system you must include the energy actually used, not some arbitrary subset. We used actual data for a modern, comprehensive system that Pedro Prieto was intimately associated with. Pedro and I assumed that where ever money was spent some energy must be used to give value to that money, otherwise the actions could not take place. Energy is used not only for running e.g. cameras but for designing , building, installing and repairing them. We used the best estimates of someone who has been doing these studies for 30 years for energy available per Euro for engineered (constructed) components, for business/financial services and more generally as detailed in our book. We have discussed at length elsewhere the need to improve these numbers, using for example methods pioneered at Univ. Illinois in the 1970s but unavailable today due to lack of funding. To say that you do not have to include all energy costs for security systems is ludicrous, since already a large number of PV systems (and cameras) have been made inoperable before their energy breakeven as desperate Spaniards have broken in and stolen e.g. copper wires.

People sitting at a desk still consume some energy, plus the (amortized) energy to construct, maintain, heat and cool buildings, computers, automobiles used in business etc etc. This was very clear in the old U. Illinois studies plus the newer Carnegie Mellon. We used a conservative value for the energy associated with these activities.

For the record we did not assume premature phase out (although its happening at much more rapid rates than expected due to maintenance issues) or give an energy cost to labor. Did you read our book? Additionally we gave credit in the last chapter to the energy quality of electricity to get an EROI of 7.2:1 and noted that PV plants were much more efficient than thermal stations in turning fossil fuels into electricity -- if you are willing to wait a long time. All of these issues are reflected in the much higher unsubsidized cost of PV electricity compared to fossil fuel electricity.

We are well aware of and respect the good work of Raugei et al. and have interacted with him on many occasions. To the best of my knowledge the last time we discussed this he did not dispute our use of more comprehensive boundaries but thought we should give more attention to increasing efficiencies of the panels. I would guess if you asked him he would say we differed over details and assumptions but he would not dismiss our studies as you wish to. Additionally at least two other recent peer reviewed studies on EROI of PVs (Graham Palmer and Weissbach et al. ) have come up with results very similar to ours. We all hope that efficiencies and EROIs are improving, but the realities are probably very different , at least in Spain (Pedro --add some).

We will be the first to say that we all need better data, and that governments are increasingly letting us down in that Department, but until we see other papers that have done their homework on actual field data as comprehensively as ours we stand behind our numbers, at least for the system we analyzed.

[StarvingLion]

"Invest in solar now while we still have the fossil fuels from fracking, deep water drilling, Canadian tar sands and mountain top removal for coal."

...and then comes the 10,000 isobreeding Liquid Flouride Thorium Reactors generating free electricity to split hydrogen from water and nanotechnology based sieves to trap carbon from the atmosphere. I'ze got this chit all figured out because I'm a genius:

Step one: trap CO2. This can be done using specially selected amines, like triethanolamine. Aminosilicones (a common chemical used in hair conditioner), can also do this.

Step two: release trapped CO2. In case of triethanolamine you'll have to boil mixture.

Step three: mix CO2 with hydrogen (hydrogen is produced by electrolysis of water). Volume proportion should be somewhere 1:3.

Step four: threat the mixture with proper catalyst. This step may be divided into two stages: reverse water-shift reaction and some variant of Fischer–Tropsch process with some type of alcohol synthesis as very interesting candidate. There are some multi-functional catalysts that can perform both stages at once.

Another variation on step 4 is the Sabatier process, which involves generating methane from CO2 and hydrogen. Typically the catalyst is Rainy nickel (powder).

The required energy in form of electrical current is probably from 1.5 to 3 times of heat of combustion of resulting fuel, which is in turn at least twice more that can be converted into actual work again.

All you need is free electricity and it works. I flunked out of high school and look how easy it is. And the bozo clown phds in Germany are fiddlin with panels and windmills.

[kublikhan]

vtsnowedin, of course anywhere dollars are spent energy is used. But there is a vast difference in the amount of energy dollar A uses vs dollar B. Sunweb illustrated this point with a machine that gulps down a gallon a fuel every minute. Contrast that with the dollars that went to pay for the CEOs of America's biggest companies, all $5.2 billion of that. How big do you think the spread is on watts per dollar between feeding that diesel beast and paying those CEO's? Trying to come up with a simple rule of x Euros = y watts is oversimplifying things IMHO.

Sunweb, about your point that solar PV's are getting built with fossil fueled infrastructure, no kidding. As you pointed out, this was already mentioned in the article I linked to. But did you catch that last sentence I quoted?
"We therefore argue that available monetary and energy resources should be funnelled in the right direction without delay, lest not enough high-EROI fossil fuels are left to support demand during times of gradual shift to renewable resources." IE, funneling our energy and monetary resources into building renewable energy now when we still have some fossil fuels left. I happen to agree with this. I know fossil fuels are providing most of the energy needed to manufacture PVs. I happen to think this is a wise use of fossil fuels. Certainly better than most of the alternative uses of fossil fuels.

Also, since you are in contact with Hall, can I assume you read his book? If so, can you tell me if he addressed recycling in the book? I was dismayed when I read summaries of the book and no mention of recycling was made. Because all of that silicon and aluminum and copper does not go "Poof!" when the solar panel dies. Nor does all of the steel in the fences, concrete in the foundation, etc. You can't recycle ash back into wood or car fumes back into gasoline. But with a tiny investment in energy, you can recycle the materials in a PV panel back into a valuable product.

I see Hall mentioned you have to triple the EROI of 2.4 to get the true energy quality of EROI 7.2:1(to reflect that PVs are producing energy in a highly useful form: electricity). This seems quite a bit better than the earlier number of 2.4 you were quoting. I hope in the future you use this 7.2 EROI value to refer to Hall's work.

[kublikhan]

Sunweb, just to build on my solar PV built with fossil fueled infrastructure point, I found an article by Raugei on this very point:

In this post, Marco Raugei makes a fundamental point about an often raised question: if we have to use fossil fuels to manufacture renewable plants, doesn't it mean that renewables are useless? Raugei's answer is a resounding "no". In fact, the EROEI of fossil fuels acts as a multiplier for the final EROEI of the whole process. It turns out that if we invest the energy of fossil fuels to build renewable plants we get an overall EROEI around 20 for a process that leads to photovoltaic plants and an even better one for wind plants. So, if we want to invest in our future, that's the way to go, until we gradually arrive to completely replace fossil fuels!

It seems that this argument is too often brought up to imply that, since PV development and deployment is currently (largely) underpinned by fossil energy, and hence PV is not (yet) a fully independent and truly 100% renewable energy technology, then "why bother" in the first place?

Actually, this kind of critique is aimed at countering the incurable technological optimists' view that "there is nothing to worry about: we can continue unabated in our reckless business-as-usual overconsumption of energy (and resources) because soon PV (and other renewables) will seamlessly step in and take the baton from dirty fossil fuels, and all will be well".

Such through-rose-tinted-glasses optimism is most likely wrong-headed and should probably be tamed. But it is also worth looking at the issue from another angle. Let us assume that the average EROI of the current mix of fossil fuels (which still represent our main sources of primary energy, globally) is some value X > 1. And let us also agree that we (as a society) need a large and ever-growing share of our energy budget in the form of electricity (to power our computers, telecommunications, trains, home appliances, etc).

Broadly speaking, we therefore have two options:
1) keep using all the oil (and other fossil fuels) directly as FEEDSTOCK fuel in conventional power plants. In so doing, we would get out roughly 1/3 of the INPUT energy as electricity (electricity production efficiency in conventional power plants being ~0.33). This would be the "quick and dirty" option, that maximizes the short-term (almost instantaneous, in fact) "bang for the buck".

2) Use the same amount of available oil (and other fossil fuels) as (direct and indirect) INPUT for the production of PV plants.

Building and deploying a modern crystalline silicon PV system requires approximately 3 GJ of primary energy per m2. What this means is that the c-Si PV system would provide an output of electricity roughly equal to 18/3 = 6 times its primary energy input, which corresponds about 6/0.33 = 18 times the amount of electricity that we would have obtained, had we burnt the fuel(s) as FEEDSTOCK in conventional power plants (option 1 above), instead of using them as INPUT for the PV plant.

A planned long-term investment might be advisable, for instance, aimed at bringing about a gradual transition. The latter is in fact what many have been advocating, often only to be met with rather negative ‘gloom and doom’ reactions by others on a number of prominent discussion forums. It seems as if, in the minds of the latter, the desire to show that ‘the emperor has no clothes’ (i.e. that PV and other renewables are not yet, and might never be in full, a real, completely independent and high-EROI alternative to fossil fuels) overrides all other considerations, and prevents them from realizing/admitting that, after all, it may still be reasonable and recommendable to try and push this slow transition forward.

To conclude, I would like to dispel all doubts and clearly state that I do agree with the aforementioned ‘pessimists’ that if we (as a society) do not come to grips with the notion that there is no such thing as infinite growth on a finite planet [6,7], and re-align our goals and ‘development’ strategies accordingly, then all the technological fixes in the world stand little to no chance of being enough to avert an ominous crash. But, why write off PV (and other renewables) and deny their value as useful tools to (hopefully) help us out on a safe slide along the slopes of a "prosperous way down"?

If we have to use fossil fuels to manufacture renewable plants, doesn't it mean that renewables are useless?