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EROEI Calculations for Solar PV Are Misleading
Solar Now Produces a Better Energy Return on Investment Than Oil <- Bullshit!

Solar can already generate more energy than oil, says major scientific review <- Bullshit!

The City Of Las Vegas Is Now Powered Entirely By Renewable Energy <- Bullshit!

EROEI Calculations for Solar PV Are Misleading
Quote
The underlying problem with EROEI calculations is that EROEI is based on a very simple model. The model works passably well in simple situations, but it was not designed to handle the complexities of intermittent renewables, such as wind and solar PV. Indirect costs, and costs that are hard to measure, tend to get left out. The result is a serious bias that tends to make the EROEIs of solar PV (as well as other intermittent energy sources, such as wind) appear far more favorable than they would be, if a level playing field were used. In fact, published EROEIs for solar PV (and wind) might be called misleading. This issue also exists for other similar calculations, such as Life Cycle Analyses and Energy Payback Periods.

Proposed types of energy alternatives are often analyzed using Energy Returned on Energy Invested (EROEI) calculations. For each type of energy product that is produced, a ratio of the energy output to energy input is calculated. A high ratio gives an indication that the particular approach is very efficient, and thus is likely to produce an inexpensive energy product. Coal is a typical of example of a fuel with high EROEI. Wood cut using a hand saw would also have a very high EROEI. On the other hand, a low ratio of energy output to energy input, such as occurs in the production of biofuels, is expected to be high cost, and thus is not suitable for expanding.

A derivative concept is "net energy." This is defined as the amount of energy added, when "Energy Input" is subtracted from "Energy Output," or variations on this amount.1 There are many other related concepts, including "Energy Payback Period" and "Life Cycle Analysis." The latter can consider materials of all sorts, not just energy materials, and can consider pollution issues as well as energy issues. My discussion here indirectly also relates to these derivative concepts, as well as to the direct calculation of EROEI.

The actual calculation of EROEI amounts varies a moderate amount from researcher to researcher. On the input side, the researcher must make decisions regarding exactly what energy inputs should be included (manufacturing the solar panel, transporting the solar panel to the construction site, building the factory that makes the solar panel, disposing of toxic waste, etc.). These energy inputs are then all converted to a common base, such as British Thermal Units (Btus). On the output side, amounts are fairly clear when the production of fossil fuels is involved, and the calculation is "at the wellhead." When output from a device such as a solar panel is involved, there are many issues to be considered, including how long the solar panel is expected to last and how many hours of solar output will actually become available given the solar panel's siting (which may not be known to the researcher). In theory, the energy costs of ongoing maintenance should come into the calculation as well, but will not be available early in the life of the panel when the calculations are made.

  • MikeS
Re: EROEI Calculations for Solar PV Are Misleading
Reply #1
Accountant tricks and subterfuge.

At the end of the day, most investors look to direct investment returns while some others will include a Total Cost of Ownership model out to 10-20 years (or, to the end of the total asset depreciation).  The problem with ALL of these models is that assumptions made even a year or two out for cost of energy are whacked; you can only make money if you include a broad range of future cost outcomes and determine what your breakpoint is with your cost structure.  And even then some technology or discovery (or event) will come along and disrupt everything.

All the investors in corn ethanol, a very slim positive EROEI (~20% or less positive), didn't invest in $100million dollar plants because of EROEI numbers; they invested because the government granted subsidies and blend quotas that meant an almost guaranteed return on investment.  Same with Germany's solar installations, a 20 year guarantee for returns if you qualify; even though the EROEI of a solar panel in Germany could be 3x less than one in Spain, Italy or Greece.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #2
Gail Tverberg makes the excellent point in many of her articles that fossil fuels, while being subsidized in part, overall are able to return an energy surplus, which is realized as profits for the oil company AND taxes remitted to the government.  Solar and wind aren't viable without subsidies and do not produce a net energy gain sufficient to allow for taxes to be skimmed off the top at any point in the process. That they cannot produce a surplus sufficient to pay taxes is strong evidence the EROEI is near zero, or negative, which means solar and wind may be a net energy sink.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #3
With the normal utility power situation solar makes economic sense* in sunny places.  Living in such a climate I have looked into it.

However, this is based on a hidden subsidy from the electric company.  Utility bills normally mix infrastructure and marginal costs together and simply give you a price per unit plus a base charge based on your maximum possible usage.  So long as that's your sole source it works reasonably well (although we have a local spat from places paying hundreds per month for big water pipes that will probably never be used other than for testing.  I haven't heard of any solutions being reached.)

However, when you introduce solar into the mix this calculation goes badly wrong.  At first it didn't matter, a trickle of solar on the grid does basically no harm so long as the inverters are properly designed.  (An inverter that can backfeed power during an outage is a deadly threat to utility crews, though!)  Too many, however, and the economics start falling apart.  In places like Hawaii the very grid starts falling apart.  (Backfeeding power into the local segment of the grid so your neighbors use it causes no hardware problems.  However, the substations are not designed to run backwards, if a grid segment has a surplus of power you have a problem.)

In the places the utility companies have successfully fought back against this subsidy the solar industry dies because it doesn't make sense anymore.

*while the numbers say it's a net plus there's a third option--wait.  The trend line for the cost of a solar installation is going down faster than the value of the power it produces.  While in the long term you'll end up with more in the bank if you go solar, you'll end up with still more in the bank if you put off the installation until the prices have dropped more.

  • RAFH
  • Have a life, already.
Re: EROEI Calculations for Solar PV Are Misleading
Reply #4
Gail Tverberg makes the excellent point in many of her articles that fossil fuels, while being subsidized in part, overall are able to return an energy surplus, which is realized as profits for the oil company AND taxes remitted to the government.  Solar and wind aren't viable without subsidies and do not produce a net energy gain sufficient to allow for taxes to be skimmed off the top at any point in the process. That they cannot produce a surplus sufficient to pay taxes is strong evidence the EROEI is near zero, or negative, which means solar and wind may be a net energy sink.
Does that include no longer having the subsidies to fossil fuels, particularly ethanol from corn? I'd think that would nearly offset any taxes they are collecting on the gasoline itself.
Are we there yet?

  • el jefe
  • asleep till 2020 or 2024
Re: EROEI Calculations for Solar PV Are Misleading
Reply #5
was about to post that ^^

  • el jefe
  • asleep till 2020 or 2024
Re: EROEI Calculations for Solar PV Are Misleading
Reply #6
also, of course, a comparison between solar and fossil fuels should include the externalized social costs imposed via climate change and its effects.  the fact that those costs are hard to quantify doesn't mean they don't exist.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #7
Solar and wind energy capture devices cannot be manufactured, shipped, installed, maintained and replaced without the existing fossil fuel-powered industrial infrastructure.  The same externalities are involved with them, as well.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #8
Prove This Wrong

Quote
Many people believe wind and solar energy capturing devices can replace a substantial percentage if not all of our fossil fuel usage.  Below you will find pictures and charts detailing the necessity of the fossil fuel supply system and the massive industrial infrastructure in this "renewable" dream.

Mark Z. Jacobson Department of Civil and Environmental Engineering, Stanford University was coauthor of another article. It can be found in Scientific America - "A Path to Sustainable Energy by 2030".
http://www.scientificamerican.com/article/a-path-to-sustainable-energy-by-2030/

They proposed that starting in 2012, 50% of the worlds needs could be supplied by 3,800,000 five megawatt wind capturing devices to be installed by 2030.  Here are the numbers:

3,800,000  5 megawatts each supply
50% of the world's energy needs in 18 years
THIS MEANS
211,111.11 Machines a year
578.39 Machines a day for 18 years
24.10 Machines each hour each day for 18 years
EACH ONE INSTALLED EACH DAY

I am choosing wind energy capturing devices because they have a higher Energy Return on Energy Invested than solar energy capturing devices.  I continually use the phrase "capturing devices" for what are usually called solar panels and wind machines because these are devices that capture the sun or wind energy.

Let me cut right to the results of this study.  The base of this 2.5 megawatt turbine in the pictures that follow (half the megawatts in the Jacobson/Delucchi study) used 45 tons of rebar and 630 yards of cement.  This computes in barrels of oil and in tons of CO2 for each base:

For the Concrete
478.8 Barrels of oil in 630 yards of concrete.
409.5 Tons of CO2 released for 630 yards of concrete.

For the Rebar
Taking a conservative 3 barrels of oil per ton the rebar would require 135 barrels of oil for the base of the 2.5 MW Turbine.
89 tons of C02  released for 45 tons of steel for the base.

All Together
The concrete and steel together for one base use
613 barrels of oil for each base alone.
Each base release 498 tons of CO2


Before looking at two of the energy requirements to install these 3800000 machines here are some interesting pictures of installing a wind energy capturing device from http://www.cashton.com/North_Wind_Turbine_Const-DM-CS-SB-2-reduced-in-size.pdf
The machine we are looking at is only 2.5 MW turbine not the larger 5 MW proposed by Jacobson and Delucch.
18 years is at the high end of the designed service life for most wind turbines.  So, the processes described and the amount of construction required would have to be a continual process in order to keep this much wind capacity operating indefinitely.

Lots of pictures follow, showing the pouring of the foundation, and the heavy lifting machinery required to install the 100 ton nacelle on top of the 330 ft tower anchored to the concrete and rebar foundation described.
Quote
The pictures clearly illustrate that the fossil fuel supply system and a vast industrial infrastructure support the manufacture and installation of these wind energy capturing devices.  The tons of rebar and the yards of concrete offer a chance to look at the energy requirements for both.  It is also important to point out that all the equipment used to install the turbines also have the fossil fuel supply system and the massive industrial infrastructure supporting them.

In researching this, the information for concrete was more definite than the range of energy required to make rebar.

REBAR



"Under the most ideal circumstances, the energy required to produce solid iron from iron oxide can never be less than 7 million Btu per ton (MMBtu/ton). Since the energy required to melt iron under the most ideal circumstances is about 1 MMBtu/ton, the inherent thermodynamic advantage of making liquid steel from scrap rather than from iron ore is about 6 MMBtu/ton. When process heat losses are included, the advantage falls in the range of 9 to 14 MMBtu/ton.  .  .  .  current total energy requirements for the pro- Petroleum provides only a small amount of enduction of finished steel products in different pIants and countries from iron ore range from 25 to 35 MMBtu/net ton."
https://www.princeton.edu/~ota/disk3/1983/8312/831210.PD



(http://www.eurosfaire.prd.fr/7pc/documents/1355390994_jrc_green_steel.pdf)

The range above supports the 25 to 35 MMBtu/net ton.  With various iron making processes, iron has a range of Btus per ton.   Converted to barrels of oil the range is 2.17 to 4.83 barrels of oil per ton of rebar.

Taking a conservative 3 barrels of oil per ton the rebar would require 135 barrels of oil for the base of the 2.5 MW Turbine.

On average, 1.8 tonnes of CO2 are emitted for every tonne of steel produced.
http://www.worldsteel.org/publications/position-papers/Steel-s-contribution-to-a-low-carbon-future.html

This means 1.98 tons of C02  emitted for every ton of steel produced.

CEMENT ENERGY

Multiply 1.10231 to convert tonnes to tons
One yard of concrete equals two tons
http://www.cemexusa.com/ProductsServices/ReadyMixConcreteFaq.aspx
Two tons equals 1.81437 tonnes
4426832.62 Btus in a yard of concrete
5800000 Btus per barrel of oil
0.76 barrels of oil in a yard of concrete
32.06 gallons of oil in a yard of concrete

0.65 tons of CO2 per yard of concrete

478.8 Barrels of oil in 630 yards of concrete
20195.52 Gallons of oil in 630 yards of concrete

409.5 Tons of CO2 per 630 yards of concrete


http://www1.eere.energy.gov/manufacturing/industries_technologies/imf/pdfs/eeroci_dec03a.pdf



THE CONCRETE PROCESS

http://www1.eere.energy.gov/manufacturing/industries_technologies/imf/pdfs/eeroci_dec03a.pdf


http://www1.eere.energy.gov/manufacturing/industries_technologies/imf/pdfs/eeroci_dec03a.pdf

On-site energy values are based on actual process measurements taken within a facility. These measurements are valuable because the on-site values are the benchmarks that industry uses to compare performance between processes, facilities, and companies. On-site measurements, however, do not account for the complete energy and environmental impact of manufacturing a product. A full accounting of the impact of manufacturing must include the energy used to produce the electricity, the fuels, and the raw materials used on-site. These "secondary" or "tacit" additions are very important from a regional, national, and global energy and environment perspective.

Normal weight concrete weighs about 4000 lb. per cubic yard. Lightweight concrete weighs about 3000 lb. per cubic yard. If a truck is carrying 10 cubic yards, then the weight of the concrete is approximately 40,000 lb.

The tonne (British and SI; SI symbol: t) or metric ton (American) is a non-SI metric unit of mass equal to 1000 kilograms; it is thus equivalent to one megagram (Mg). 1000 kilograms is equivalent to approximately 2‚ÄČ204.6 pounds.




http://www1.eere.energy.gov/manufacturing/industries_technologies/imf/pdfs/eeroci_dec03a.pdf

It is important to realize we have only looked at the energy for the concrete and rebar for the base of a 2.5 MMwatt turbine.  Behind this device and most sun and wind capturing devices are a global system of providing energy and materials.  And this support is further supported.   Here is one mining truck among a worldwide fleet of trucks that also must be manufactured.  It is like a thread on a knitted sweater that when you pull it thinking you will get a small piece, you end up with a whole ball of yarn.



  • Last Edit: December 23, 2016, 05:14:24 PM by Autonemesis

Re: EROEI Calculations for Solar PV Are Misleading
Reply #9

  • RAFH
  • Have a life, already.
Re: EROEI Calculations for Solar PV Are Misleading
Reply #10
Thorium.
Are we there yet?

Re: EROEI Calculations for Solar PV Are Misleading
Reply #11
Anti-matter
Cold fusion

Re: EROEI Calculations for Solar PV Are Misleading
Reply #12
Solar and wind energy capture devices cannot be manufactured, shipped, installed, maintained and replaced without the existing fossil fuel-powered industrial infrastructure.  The same externalities are involved with them, as well.
The problem with this sort of analysis, and really all energy analysis, is that it is based on the outdated grid and an impossibly complex set of externalized costs.

One of my good friends gave a TED talk here in Portland a few years ago about the smart grid that is sort of being installed, though not in any meaningful way yet, that will change the way we calculate a lot of those variables. His take on renewables is super complex and conversations with him on the topic often clear the room but basically I think his point is that the infrastructure defines a lot more of the analysis than we'd like to believe. It is essentially a paradigm issue.

To clarify, his Ted talk is about the smart grid itself. The rest I've picked up in conversations. What I basically gather is that you can't disentangle the regulatory environment, the economic environment, and the infrastructure environment in any meaningful way because they each feedback into each other.

Take that for what it's worth. It's not a definitive statement.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

Re: EROEI Calculations for Solar PV Are Misleading
Reply #13
Solar and wind energy capture devices cannot be manufactured, shipped, installed, maintained and replaced without the existing fossil fuel-powered industrial infrastructure.  The same externalities are involved with them, as well.
It's also a matter of usable lifespan. Business financing typically has to be amortized over ten years so ROI is usually connected to that business practice. That skews solar especially. Plus, new technology yada yada.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • RAFH
  • Have a life, already.
Re: EROEI Calculations for Solar PV Are Misleading
Reply #14
Anti-matter
Cold fusion
Actually, LFTR works. The US had a working thorium reactor at Oak Ridge for years back in the 50s and 60s. That direction was pretty much abandoned because it didn't produce weapons grade products. Which was pretty much what the US nuclear industry was all about. That it produced electricity was simply a bonus.
Are we there yet?

Re: EROEI Calculations for Solar PV Are Misleading
Reply #15
Is there any significant effort being made to put thorium reactors into service? No? Then it helps the situation exactly as much as science fiction power sources. 

Re: EROEI Calculations for Solar PV Are Misleading
Reply #16
Anyway, resources and population have no choice but to align eventually. I don't think we can ever escape Malthus so we are approaching apocalypse ... whatever paths the rivers choose, the eventually lead to the sea.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

Re: EROEI Calculations for Solar PV Are Misleading
Reply #17
There may come a realization before the end, that energy capture devices are hastening, not delaying, the inevitable collapse. The industrial infrastructure we have already has proved itself capable of significant geo-engineering feats. The last resort to eek out a few more decades may be to remove pollution controls so that particulates and sulfates can accumulate in the atmosphere again, not to mention, increase the death rate.  It probably won't work, but what we're doing now is definitely not working.

One thing I am sure will not happen is people voluntarily walking into the disintegration chamber, like that Star Trek episode.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #18
I am always surprised that batteries have become an environmental solution rather than problem.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

Re: EROEI Calculations for Solar PV Are Misleading
Reply #19
1 cubic mile of oil = roughly 1 year's consumption

Re: EROEI Calculations for Solar PV Are Misleading
Reply #20
Trump's potentially toxic effect on the solar industry
Quote
The US solar industry is a bigger employer than oil and gas extraction, but it fears disruption under a Trump presidency



The Guardian's source: US solar industry bigger employer than oil & gas extraction
Quote
The US solar workforce expanded by 20% last year, reaching nearly 209,000 jobs, despite a modest decline in the PV manufacturing sector, according to a new report.

One out of every 83 jobs created in the US in 2015 was in the solar industry, the report says.

With a total current workforce of 208,859, the US solar industry now employs three times as many workers as the country's coal-mining industry. And the solar industry is now a bigger employer than many sub-sectors within the oil and gas industry - including the extraction sector, which employs 187,200 people after shedding jobs last year, and the pipeline construction sector, which employs 129,500.

Taking these figures at face value, it took about as many workers to produce that tiny sliver of red in Gail's graph, as it took to produce the major portion in blue, PLUS all the non-electric energy produced by the fossil fuel industry.

Conversion of the electric grid entirely from fossil fuels to solar + wind looks like it would require more workers than the current population of the United States, but then there would be nobody else available to build an all-electric vehicle fleet, never mind growing food, operating sanitation systems and other public infrastructure, teaching the children of the workers, and all the rest of what constitutes our great American republic.

Re: EROEI Calculations for Solar PV Are Misleading
Reply #21
That graphic with the cubic mile of oil illustrates the necessary shift to distributed power production.
Love is like a magic penny
 if you hold it tight you won't have any
if you give it away you'll have so many
they'll be rolling all over the floor

  • SR-71
  • Schmewbie
Re: EROEI Calculations for Solar PV Are Misleading
Reply #22
The well count was very low last year for oil extraction.  Is a comparison of employment between a nascent technology with far to run and a mature, currently contracting industry a meaningful comparison?  Coal is putting itself out of business on cost basis with gas, and that after decades of subsidy for coal. 

Looking at some of the numbers from the mile^3 graphic, it seems almost trivial.  91,000,000 solar panels is less than a third of a panel per capita.  I think we can swing that for 50 years.  We made over 300,000 aircraft in the 4 years of WWII, and many more land military vehicles, ships, weapons and equipment.  That with half the population, and a good fraction of that employed in the military.

  • SR-71
  • Schmewbie
Re: EROEI Calculations for Solar PV Are Misleading
Reply #23


Some rigs are starting to come back online.  It helps that OPEC finally agreed to curtail production.  Look how far it fell when OPEC refused to squeeze off in 2014.  The fracked oil couldn't compete on cost basis with the old conventional fields.  The old fields are depleting and new discoveries can't keep pace.  Fracked wells fizzle after just a few years. 

Re: EROEI Calculations for Solar PV Are Misleading
Reply #24
That graphic with the cubic mile of oil illustrates the necessary shift to distributed power production.

Let's see an aluminum smelter run off of solar panels and wind generators alone, producing enough aluminum to build and maintain it's own power source for the lifetime of the smelter, and sufficient surplus aluminum to sell to keep the smelter business a going concern.

https://en.wikipedia.org/wiki/Aluminium_smelting
Quote
Aluminum smelting ... is an electrolytic process, so an aluminum smelter uses prodigious amounts of electricity; they tend to be located very close to large power stations, often hydro-electric ones, and near ports since almost all of them use imported alumina. A large amount of carbon is also used in this process, resulting in significant amounts of greenhouse gas emissions.

  • Last Edit: December 25, 2016, 10:37:50 AM by Autonemesis