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Four Ways the Attack on Wind and Solar Is Wrong

The first mistake in Gail Tverberg’s Ten Reasons Intermittent Renewables (Wind and Solar PV) are a Problem is using the outdated term “intermittent” for renewables.
“The more accurate term is ‘variable renewables,’” explains energy consultant Nancy LaPlaca. “The word ‘intermittent’ reinforces the impression that wind and solar are unreliable. The word ‘variable’ underscores the fact that, like all energy sources, wind and solar can and must be managed by grid operators.”
“Wind and solar energy are variable because their output changes gradually over many hours, and those changes can be predicted,” explains American Wind Energy Association (AWEA) Senior Electric Industry Analyst Michael Goggin. “Fossil and nuclear power plants are the ones that are intermittent, as their failures occur instantaneously and without warning, which is far more costly for grid operators.”
Among the ten points in Tverberg’s 3,000-plus word essay are four misinformed accusations:
  1. Renewables don’t replace oil,
  2. Renewables don’t reduce greenhouse gas emissions,
  3. Renewables cost too much, and
  4. Renewables can’t grow fast enough.

I’ll take each of these in turn…

Accusation #1: Renewables don’t replace oil

“Wind and solar PV do not fix our oil problem,” she writes. “Our big problem is with oil.”

That is an irrelevant “straw man” argument, Goggin responds. “Nobody who knows what they’re talking about ever claimed renewables replace oil except in minor applications.”

To address the oil problem, electric car advocate Paul Scott argues, put plug-in vehicles on the grid and clean up the grid.

Accusation #2: Renewables don’t reduce greenhouse gas emissions

Cleaning up the grid means more wind and solar. Tverberg’s argument that they do not reduce greenhouse gas (GHG) emissions is “completely debunked,” Goggin says, by the conclusions of the comprehensive Life Cycle Harmonization Project from the National Renewable Energy Laboratory (NREL) (summarized in this fact sheet).

Though Tverberg claims there are only superficial “top of the iceberg” evaluations of various sources’ GHGs, the NREL study incorporates:

  • upstream factors: raw materials extraction, construction materials manufacture, and power plant construction
  • fuel cycle factors: resource extraction and production, processing and conversion, and delivery to site
  • operation factors: combustion, maintenance, and operations, and
  • downstream factors: dismantling, decommissioning, disposal and recycling.

The systematic NREL literature assessment of thousands of peer-reviewed life cycle analyses (LCAs) published over the last 30 years sorted out the data and technical information. “Total life cycle GHG emissions from renewables and nuclear energy are much lower and generally less variable than those from fossil fuels,” the LCA analysis concludes. “From cradle to grave, coal-fired electricity releases about 20 times more GHGs per kilowatt-hour than solar, wind, and nuclear electricity.”

NREL’s work is so thorough its findings and methods were incorporated into the work of the Intergovernmental Panel on Climate Change.

Ramping up renewables tends to raise CO2 emissions “by ramping up China’s economy,” Tverberg argues. “The benefit China gets from its renewable sales is leveraged several times, as it allows the country to build new homes, roads, and schools, and businesses to service the new manufacturing. In China, the vast majority of manufacturing is with coal.”

Tverberg’s idea that renewables cause China’s increased emissions “is absurd,” Goggin says.  “The chart in her article clearly shows China has ramped up coal use to meet increased overall energy demand.”

Hundreds of industries make up China’s $12 trillion-plus manufacturing sector. “It may be correct to say that manufacturing renewables ramps up China’s economy,” explains energy analyst and Global Footprint Network Policy Officer Chris Nelder, “but that’s true for everything that China does. Why single out renewables?”

In solar, the U.S. and Germany do much of the polysilicon refining, the most energy intensive part of module manufacturing. “And over 70 percent of U.S. wind components are made here,” Goggin says.

 “Renewables raise world CO2 emissions indirectly by making the country using them less competitive,” Tverberg argues. The higher electricity cost, she explains, drives manufacturing to countries that use lower-priced fossil energy sources.

“I am not aware of any evidence that using renewables has made any country less competitive by raising the price of manufactured goods,” Nelder says. “The OECD has been outsourcing manufacturing to China for decades. Separating out the effect of renewables is extremely difficult.”

Accusation #3: Renewables cost too much

The higher cost of renewables-generated electricity also drives governments to balance their energy mixes with cheap fossil sources. “This seems to be at least part of the problem behind Germany’s difficulties with renewables,” Tverberg speculates.

Her observations about the costs of renewables don’t stand up to scrutiny. A recent Synapse Energy Economics report showed that doubling the use of wind energy in the Mid-Atlantic and Great Lakes states will save consumers a net $6.9 billion per year, after costs. And, Goggin adds, “U.S. Department of Energy data confirm that consumers in the top wind energy producing states have seen their electric rates increase at around half the rate of consumers in states that produce less wind energy.”

Recent articles “have misleadingly looked at small snapshots in time that miss the large consumer savings and pollution reductions wind energy is producing in Germany,” Goggin  wrote recently.

“Germany has already seen a 20 percent drop in wholesale electricity prices over the last year, in large part because wind and solar energy displace more expensive sources of energy,” he points out.

“Renewable energy has reduced wholesale prices by $0.012 cents per kilowatt-hour,” Clean Technica reported last fall from a report by German research firm BrainPool. For Germany’s predicted 2014 consumption of 482 terawatt-hours, “renewable energy will reduce wholesale prices by EUR 5.784 billion.”

German electricity customers are only beginning to see these savings because of the year or two regulatory lag in updating retail electricity rates,” Goggin wrote. And, because of a variety of other factors, “renewable costs appear larger than they are.”

Tverberg also says – again with inadequate documentation – that renewables are too costly “because current laws overcompensate owners of intermittent renewables relative to the value they provide to the grid.”

She argues that at retail rates renewables are overcompensated. But while there is a large difference between retail and wholesale electricity prices, Goggin acknowledges, she ignores the fact that all utility-scale projects, including wind and solar, are paid at a wholesale rate. And the difference between wholesale and retail rates is almost entirely made up of the cost of distribution lines that deliver electricity from all generation sources to homes and businesses. 

Accusation #4: Renewables can’t grow fast enough

It is doubtful renewables production can ramp “to even 5 percent of the world’s energy supply,” Tverberg argues in one paragraph. But when renewables production does ramp up to meet world demand, she says in another paragraph, there will be “polluting minerals” and “toxic materials” to deal with. Besides the obvious contradiction, she is mistaken on the first point and misguided on the second.

Wind and solar are among the world’s fastest growing energy sources. They were over 5.8 percent of U.S. generating capacity through November 2013 and were about 54 percent of the new capacity installed in 2012. Global solar capacity grew 42 percent and wind capacity grew 19 percent in 2012, according to the most recent IEA numbers. They are projected to be 10 percent of global electricity by 2020.

“Globally non-hydro renewables now have a compound annual growth rate of 5.9 percent and rising,” Nelder notes.  “Of course it takes time. All transitions have. And they all grow very slowly for the first few decades.”

The pollutants and toxicities associated with renewables pale in comparison to nuclear waste and the poisons that spew from coal plants, LaPlaca points out.

“Making energy from anything causes pollution,” Nelder adds. The question is how bad is the pollution relative to the alternatives? Tverberg presents no data.”

Unlike conventional power plant life spans of 40 years, Tverberg claims, referencing a Renewable Energy Foundation analysis, “it may not be economic to operate wind turbines for more than 12 years to 15 years.”

But Danish Energy Agency data shows no evidence of “an age-related performance drop,”reported Windpower Monthly’s David Milborrow. “Performance generally appears to be maintained at a consistent level, with only a slight decline with age — one in line with other types of power plants.”

Solar PV modules are similarly showing long term steady performance, according torecent research.

Conventional power plants require expensive regular maintenance and periodically shut down to replace or refurbish major components. Most wind and solar installations generally require little more than basic maintenance, Goggin notes.


Much of Tverberg’s analysis is based on an Energy Returned on Energy Invested perspective. But, Nelder says, “EROEI and LCA analyses are deeply problematic when comparing renewables to fossil fuels. Is there an analysis showing that over 20-plus years, a new investment made today in renewables is more expensive than one in fossil fuels? And anyway, what is the alternative? That we stay committed to coal?”

Herman Trabish's picture

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Josh Nilsen's picture
Josh Nilsen on Jan 27, 2014

I try to be objective but every single day a new article comes out saying how intermittant renewables are too expensive and cannot work, then another article saying how they’re cheap, saving money, and they do work.

Based on the growth trajectory of renewables, I’d say they’re working quite well.

Robert Wilson's picture
Robert Wilson on Jan 27, 2014


Gail’s piece was riddled with nonsense and half truths. However this response is not much better. And ultimately it is just one long argument from authority. The main authority here however seems to be a PR man for the wind industry. Saying critics of renewables are wrong by literally citing renewable industry talking points is not exactly going to convince them of anything. Can we not do better than this? 

The piece also gets off to a dreadful start, by telling us that we should call renewables “variable” and not “intermittent.” This is just public relations, not serious analysis. The term “intermitency” has been in wide use for years, and people know what it means. Using the word “variable” in its place is an abuse of language in the name of public relations.

You also should not buy talking points about renewables lowering German electricity prices. People who claim this should know better. The actual cost of renewables in Germany is added on to the wholesale price, so focusing on the wholesale price alone is misleading (and I suspect in some cases deliberately so). Say what you want about renewables in Germany, but the idea that they aren’t increasing prices is ludicrous. Just ask their new energy minister. The Germany American environmentalists think exists is a mythical place. In this case you really should have double checked Goggin’s misleading talking point. This is after all very easy to do, simply by checking what German retail prices are and what they are composed of.


Schalk Cloete's picture
Schalk Cloete on Jan 27, 2014

This article could lead to some interesting discussions. Here is my two cents’ worth:

First off, the intermittent vs variable issue. I use the term “intermittent” because it captures the fact that generation from wind turbines and solar panels stops and starts and can generate nothing for a long time. To me, the term “variable” does not correctly capture the long periods of zero generation and also implies that output can be varied willingly. 

Of course it is true that, if you couple a lot of wind turbines and solar panels together in a supergrid, the number of hours where total generation is zero can become very small. However, even for large supergrid areas, the percentage of wind power that can qualify as thermal plant reliability (~5% unscheduled downtime) will not easily rise above 10-20%. This was discussed a little more thoroughly in a previous comment

Now on to the four points.

1. Much of Gail’s thesis revolves around oil, so it is clear why the obvous inability of solar and wind to solve our short-to-medium term oil problem would form an important part of her argument. 

More importantly, one of the most important argument against wind and solar technology-forcing is that it is the slowest and most expensive way in which to abate CO2. To this argument, activists often respond that solar and wind is also very important when it comes to energy security – something which is mostly related to oil. 

2. Here, Gail’s argument is based on drawing very wide boundaries. Wider boundaries including the effects of balancing intermittency and even the carbon footprints of everyone employed along the solar/wind value chain results in much higher fossil fuel inputs per solar/wind output than commonly assumed.

Personally, I’m still trying the make up my mind about this issue, but papers such as the Weisbach et al. study shows that wind and solar have a very low EROI compared to other generation technologies, implicitly implying that their carbon footprints can be quite large (since almost 90% of global energy is still fossil). Then there are also factors such as the rebound effect and the gas-to-coal switching currently happening in Germany. 

3. It is true that low-penetration onshore wind and, in rare cases, solar PV can already be cost-competitive in developed nations. This is under the assumption of negligible balancing costs, low discount rates and high prices for new conventional plants.

Since solar/wind are capital-intensive technologies, the discount rate is an especially important variable. In stagnating developed world economies where interest rates are essentially zero and government subsidy programs create a low level of perceived risk, discount rates can be very low, but in the developing world (which is the part of the world that all of us should be talking about), the situation is very different. For solar PV, changing from a discount rate of 2.4% used by Fraunhofer to 10% used by IRENA more than doubles the LCOE. 

4. There is very little doubt in my mind that wind/solar cannot scale up nearly fast enough within practical, economic and political restraints to have a meaningful impact within the timeframes prescribed by climate science. I did a post about this some time back.

Bob Meinetz's picture
Bob Meinetz on Jan 27, 2014

Herman, picking apart the semantics of Gail Tverberg’s characterization of renewables is more than a bit silly. Wind and solar are quite literally intermittent – there are times when they provide no power at all, and  except for nighttime the timing is largely unpredictable. Wind’s capacity factor is 30%; solar is 15% or less. Nuclear’s capacity factor is 92%, with about three-fourths of nuclear outages being planned refueling. There is no comparison.

As far as “renewables replacing oil”, suffice to say that there are days in California when wind and solar don’t even generate enough energy to power the electric cars which are already here. As we progress to a higher saturation of EVs, drivers will need to know they can get to work whether the wind is blowing or not. While I disagree with Gail on the value of oil to transportation or even the economy, wind and solar will never be a robust source of clean energy which can support this transition.

In general, quoting a rep for a renewables industry association, and even citing data from NREL, are more examples of the echo chamber which amplifies renewables talking points. The industry, as well as NREL, are both completely dependent on luxurious government subsidies for their existence: they would wither and die without them. Ignoring whether these subsidies are justified  (to a lesser extent, in my opinion, they are) objective data from real-world implementation of renewables is not encouraging for carbon emissions. In the case of Germany, wind and solar are failing miserably to address climate change. They’ve increased carbon emissions dramatically, with no sign this situation will change in the near future.

Paul O's picture
Paul O on Jan 28, 2014


I despise double-speak, whether it is from a Chiropractor, or from a Journalist.

If we need more power from a coal plant, we shove in more fuel and up goes the power….That is Variable power. If we need more power from wind mills we send a telegram to the Pope and say a prayer, and hope He is listening….That is intermitent power.

Unfortunately you already knew this, didn’t you?

Keith Pickering's picture
Keith Pickering on Jan 28, 2014

“And anyway, what is the alternative? That we stay committed to coal?”

No. The alternative is hydro, where available, and nuclear, where not.

Is wind cheap? Yes. Is wind fossil-free? Yes. The problem is that wind can’t be BOTH cheap AND fossil-free at the same time.

With wind (and solar), you have a choice: you can eliminate fossil fuels from the grid entirely, and triple the cost of electricity; OR, you can have cheap renewable electricity with fossil (gas) backup. If you want non-fossil electricity AND you want it cheaply, nuclear and hydro are the only options.

The problem with renewables (and yes, they ARE intermittent) is a problem we are only now just beginning to see, because it only becomes a problem at significant grid penetration levels (which means more than about 25%). That is, the more you depend on the intermittent generators, the more you need load-following generation on the grid to step in when the wind isn’t blowing and the sun isn’t shining. 

Currently that means natural gas combustion turbines (NGCT) which are inefficient but ramp up rapidly. Combined cycle gas turbines (CCGT) are much more efficient, but ramp up more slowly. But here’s the rub: let’s say you have a 100MW wind farm and couple that with a 100MW NGCT as backup. The wind farm has a capacity factor of 30%, so 70% of the time, the actual electricity is being generated by the NGCT. If you compare the carbon emissions from the inefficient NGCT running 70% of the time, it’s actually higher than a CCGT running 100% of the time. 

Since wind+NGCT has more carbon emissions than CCGT, what’s the advantange in building wind at all? Why not just build CCGT and be done with it?

Now it’s theoretically possible (in the US, but not often elsewhere) to build a grid so continentally large that wind farms in one state can backup wind farms in another state a thousand miles away. The problem there is that when you build that much wind onto the grid, enough to generate all the power all the time, you have to curtail production on most turbines most of the time. Which drives up the cost of wind substantially, because it drives capacity factors down by equally huge margins. The U. Delaware study last year determined that following that path would roughly triple the price of electricity.

On the other hand, if you’re building a zero-fossil grid, you could backup wind with nuclear. But if you’ve got nuclear, why build wind? You can simply run nuclear all the time.

Rick Engebretson's picture
Rick Engebretson on Jan 28, 2014

First, I’m grateful for Gail’s well reasoned energy and economic writings. And I deeply resent this piece. But the writer does ask the all important question, “what can we do(?),” which Gail seems to lack.

“Intermittent” energy isn’t bad. Unreliable energy is bad. Pretend energy is bad. A car is reliably intermittent energy. A solar panel on a 30 below zero night without propane in Minnesota is reliably pretend energy. So let’s drop the semantic doublespeak and maybe talk energy, since it is important.

Burning coal entered a new phase when steam boilers were invented, not that long ago. The steam powered mechanical energy systems. Then electricity was invented.

Steam energy remains the core energy transformer. External heat source engines, like coal and nuclear, are similar to internal combustion sources like piston and jet engines, and even some rocket engines. They all push expanding water vapor.

So maybe we could look at water based “renewable energy,” as many suggest.

My narrow vision is not hydro or geothermal or OTEC, etc., and could be totally wrong. But I think all those high energy solar photons could be better used ionizing water protons rather than ionizing silicon crystal electrons. Green plants do it for green plants, maybe people could do it for people.

Bob Meinetz's picture
Bob Meinetz on Jan 28, 2014

Todd, while much is made of the possibility for wind and solar overcoming local variability by networking larger areas, the same approach is available to over/undergeneration of nuclear, with more predictable results.

The French, in particular, would take issue with your contention that nuclear is not dispatchable. Électricité de France (EDF), with the challenge of managing the country’s power needs using generation which is 90% nuclear, combines reactors’ output to match demand in real time throughout the country competitively and economically. Due to higher reactivity, reactors which have been recently refueled are more adept at short-term load following, and ramping rates of 10%/hr are common. Plants being built today, eg according to European Utilities’ Requirements (EUR), have this load-following capacity fully built in. Less-nimble reactors with fuel assemblies >~65% into their life cycle are used for baseload.

Every power plant is run as much as possible to maximize ROI, and nuclear is no exception. That France’s nuclear industry is economical is reflected in French electricity rates, which are about 1/2 of high-renewables Germany and Denmark, with lower per-capita carbon emissions. Forcing customers to pay twice as much for dirtier energy is a legitimate criticism, and one not easily deflected by accusations of “stigmatizing and name-calling”.

Kevon Martis's picture
Kevon Martis on Jan 28, 2014

Whenever a wind booster says that wind is cheap it must immediately be followed up with 2 simple questions: where and when?

Do they mean in Michigan where the capacity weighted average price of subsidized wind is $80/MWh and fixed for twenty years?

Or in IA where it is priced in the low $30’s?

Or in Texas where wind is reportedly selling in the $20’s?

And do they mean when it is dumped into the grid at night at times of low demand and hence low (or even negative) value?

Or those historically rare moments when wind enegry happens to arrive in July and August and thus times of high demand/price?

And has any wind promoter anywhere suggested a fair price for wind enegry that takes into consideration it’s lack of upward dispatch? Should that handicap be $5/MWh? $10? $50?

How does one value an employee that shows up on his/her own schedule and seldom when there is real work to do?

And to whose account do we credit the roughly $35/MWh of tax incentives to achieve the pricing referenced above? 

And before one responds “coal externalities” as a rationlae for those substantial subsidies, I would hope that wind boosters would also demand a cost accounting of wind generation’s externalities: low energy density and thus high land use, high relative transmission costs, noise pollution of very wide areas, human health and property value impacts as well as endangered species impacts. And of course there are the materials intensive nature of wind generation including truly massive tonnages of non-recyclable yet disposable turbine rotors.

And some accounting of the positive externalities of cheap fossil-fueled generation must also considered.



Thomas Garven's picture
Thomas Garven on Jan 29, 2014

I commented on Gail’s initial posting and my comment basically stated that I believed she was out of her comfort zone when she started writing about renewables and fossil fuels as I would be if I were to write about something like demographics.  Furthermore my knowledge of the oil industry is basically what I read at the “Energy Trends Insider”.  I can however tell you how a tank farm works since I actually worked at one for a few months.  Of course my knowledge of the coal industry is even less.  Like most people,  we each have an area of expertise and for me that is the public utility sector and the fabrication and construction, licensing and operation of nuclear power plants.    

I always enjoy reading Gail’s postings and her vision of the future when it comes to her area of expertise.  But I take everyones writings including MY OWN with a grain of salt.  For example, here is a short quote indicating where California is going with their energy policy  which is straight out of their Independent System Operators [ISO] vision for the future.  Here is the link so you can read all of the 11 page strategy if desired.

“California policy goals and the climate change imperatives are driving generation portfolios toward cleaner and renewable resources. By 2015, we project that nearly 25 percent of California load will be served by renewable resources, compared to just 17 percent in 2010. In 2012 alone, over 670 megawatts of new solar generation were connected to the ISO grid, enough to power over 500,000 homes.”.  

Solar and wind are not going away.  In fact I can drive 50 miles from my Arizona home and point out at least two [2] new solar PV plants under construction.  Of course there are some individuals who for various reasons just wished that renewable energy systems would go away.  However, the reality seems to be reverse.  And things like hydro, hydro kinetic, geothermal and biomass are not going away either but are continuing to grow.  And for every kilowatt of power created by some form of renewable energy that is one less kW we didn’t get from burning something.

So let’s talk for just a little about how a typical grid system works.  Here is a link to todays ISO grid [California] operation. Please go to this page and click on “Supply and Demand” and then “Renewable’s for a look.

As shown todays peak demand was 27,325 MW.  Tomorrows peak is expected to be 29,627.  Solar peaked around noon at about 2,840 MW.  The output from the Wind sector was all over the place today.  

So Gail is correct, wind and solar are variable AND intermittent just like every other energy source.  Coal, nuclear, natural gas and combined cycle units are ALL variable and ALL are intermittent.  The sun is the closest thing we have to a continuous source of energy and even that will burn out in about a billion years.    

Did anyone notice how well the “demand” line and “actual lines” followed each other?  Did you also note the amount of reserves available?  We don’t need to add ONE single new power plant when we add more solar at least up to about 20,000 MW and we are a long way from that happening, LOL.  But it is also true that for large power grids; when you add another MW of renewable energy; something else goes off-line and that could be coal or natural gas or some other form of power.  Sort of makes the variable and intermittent argument mute wouldn’t you say.  When you KNOW a day in advance what the demand will be, then planning for the type[s]s of energy needed become fairly easy.  

So Herman, Rick, Keith, Paul and Todd that is where the State of California has decided to go which may not be applicable to where you live.  It is based on the work of literally hundreds of engineers, utility owners and the CEO’s from multiple utilities in the Western part of the United States.  And I guess you could say the “people” also helped by voting in support of renewable energy systems not just once but multiple times.  So lets all be nice to each other and have a great day since even the weather is intermittently hot and cold and therefor variable. 

Bob Meinetz's picture
Bob Meinetz on Jan 29, 2014

Thomas, regarding your comment

We don’t need to add ONE single new power plant when we add more solar at least up to about 20,000 MW and we are a long way from that happening…

You’re assuming every day will be sunny. I’m assuming CA will continue to grow, once and while we’ll have mostly cloudy skies, and everyone won’t want their refrigerator and lights to go out.

Solar guarantees we’ll be locked into a future relying on at least 50% fossil fuels. That’s not good enough.

Thomas Garven's picture
Thomas Garven on Jan 29, 2014

Hi Bob:

Solar is currently being installed in at least five [5] states that feed into the CAISO grid.  In  Northern California, Southern California, Nevada, Arizona, New Mexico and Colorado which depending on grid needs, some of it goes to California.  A complete cloud out or rain out over that large of an area is highly unlikely but certainly not impossible. 

So lets assume [I love that word] for a minute that ALL of the solar in every state mentioned was covered with either clouds or rain.  But even if that were the case, there are EXISTING generating stations that are already running to pick up the load for a day or week or however long the conditions lasted.  

Please look at the ISO charts again.  Most days energy demand start out at about 20,000 MW which is a level of demand needed to meet basic grid needs.  We frequently call this 20,000 MW “base load” power.  It is the power needed to run refrigerators, keep a few lights on, run the traffic signals and for essential emergency services at night, There are more than enough power plants running to meet this base load requirement every day regardless of weather conditions.    

So lets assume we added 20,000 MW of solar which of course doesn’t start up until the sun comes up.  If it was a good solar day when the sun came up at about 7:30 a.m. we would start getting some power. We could then begin shutting down some of those base load power plants we had running all night.  As the day rolled on, and solar power increase, we could shut down even more of these plants; oh but wait, demand is now higher than our 20,000 MW of solar can provide; people are going to work and using more power so I guess we better keep at least 2 or 3 of these other power plants running and increase their power output as the day rolls on.     

But wait, we also just noticed on the satellite images that rain is moving in over Northern California so we are about to loose 600 MW of our solar power at about 3:00 pm.  I better bring some gas peaking units  online at about 2:30 in hot standby to be ready to pick up the load since I am going to loose part of my solar power.  

At no place in this discussion have we built any NEW power plant.  Solar in this case is acting like a peaking power plant that is taking PART of the load off other generating systems.  These other systems are most likely coal plants in Northern Arizona [and some nuclear], Colorado and Utah and some natural gas peaking and combined cycle plants spread around California.  

So Bob you are correct.  On a cloudy day solar power production could decrease and therefor backup generation which we currently HAVE would be needed.  You are also correct that until enough solar was available to cover both our daytime and night time needs by the use of some technology like storage; we can only count on solar for PART of our energy needs.  Solar is but ONE of many energy solutions we will need to meet our growing energy needs. 

Excellent question.  I hope my response helped.

Bob Meinetz's picture
Bob Meinetz on Jan 29, 2014

Thomas, you overestimate the capability of other states to contribute to CAISO’s power demands on an as-needed basis. While several utilities send baseload power to CA as the result of long term contracts (hydro on the Pacific DC Intertie; nuclear from Palo Verde in AZ) load following is a different matter. Currently only one out-of-state facility, Hidden Hills in Nevada, is on CAISO’s  Master Control Area Generating Capability List:

Under the RPS law, California’s investor-owned utilities must derive 33% of their power from renewable sources by 2020. Due to the complex nature of electrical power trades between CaISO and other grid operators, counting Hidden Hills power toward RPS goals would have required grid operators to use a process called “dynamic transfer,” which most grid operators are reluctant to do as it is expensive and complex even by the arcane standards of grid operation.

You’ll notice also that peak demand is at 6PM when solar is finished and natural gas must take over. This is a dependency which will last as long as our solar panels do. Very few analysts believe renewables generation beyond 50% is practical, so we’re stuck with 50% fossils – for how long? 50 years? 100 years?

Solar may be one way to get energy, and like others I can dredge up any number of industry or academic white papers which will explain how all the pieces are going to fit together in the coming Renewables Panacea. Unfortunately, real world experience tells a different story. By investing in wind and solar, we’re going backwards.

Bas Gresnigt's picture
Bas Gresnigt on Jan 29, 2014


“<i>… wind generation’s externalities: low energy density and thus high land use…</i>”
Reality shows that the opposite is true.

Nuclear power plants have an energe density of ~2KW/m2 (not including uranium mine and transport).
An 8MW wind turbine has a footprint of ~20x20meter which is 400m2.
That implies an energy density of 20KW/m2, 10 times more than nuclear (and no fuel mines).

Note that all land between those high wind turbines is used as usual, so one cannot attribute that land to wind turbines.




Rick Engebretson's picture
Rick Engebretson on Jan 29, 2014

Thomas, you are a competent gentleman, and write about important things. Thank you. Please say more. But it is unacceptable to continue mis-represent the writings of another (Gail). If you want to write about the word “intermittent” and grid operation, please do.

Apparently, even the wind and solar industry emphatically agree with the enumerated points in Gail’s article that these systems will not replace oil (calling it a “straw man”). So what’s the point here?? Intimidation??


Keith Pickering's picture
Keith Pickering on Jan 29, 2014

So existing generators take up the slack when conditions warrant. And you don’t see the problem with that?

Are those existing gerenators fossil fueled? Of course. So how do we make those existing slack-taker-uppers <b>non-fossil</b>, for nights with no wind? How do we build a 100% non-fossil grid?

Show me how to build a 100% non-fossil grid, including one that works on windless nights, without nuclear. You’re missing the goal here. The goal is not less carbon emissions. The goal is ZERO carbon emissions. Anything less is climate catastrophe.


Keith Pickering's picture
Keith Pickering on Jan 29, 2014

Nancy, you have been badly misinformed. Using FY2010 budeting and 2012 production, direct and indirect subsidies for coal were $0.90/MWh, for natural gas $2.28/MWh, for nuclear $3.25/MWh, for wind $35.41/MWh, and for solar $262.08/MWh.

If Fukushima proves anything, it’s how safe nuclear power really is. A magnitude 9 earthquake and 42-foot tsunami killed 20,000 people and destroyed three reactors, and yet the subsequent radiation release killed zero and injured zero. The fear of radiation, however, killed over 1000 people in an evacutation that was mostly unnecessary.

Thomas Garven's picture
Thomas Garven on Jan 29, 2014

Hi Bob: A couple of your very good points are in quotes below.  

“You’ll notice also that peak demand is at 6PM when solar is finished and natural gas must take over”

Or more coal power from the Four Corners, more hydro from the Pacific Northwest, or more nuclear from Palo Verde or as you stated, more natural gas use.  Many options are available.  Also the winter peak is as you stated after solar production has stopped.  However it might also be wise to revisit peak demand  during the summer.  It is also true that we are seeing an increase in the use of natural gas which is not necessarily a bad thing depending on your view of Climate Change.  Especially the use of more Combined Cycle Gas plants which are significantly more efficient than older technology. 

A few words about natural gas seem to be in order here.

Since I admit to knowing very little about the natural gas industry I can only repeat what I read at other blog sites like the Energy Trend Insider and of course this website and others.  From what I read based on historical usage; fracked natural gas well production can be rather short lived; short being about 5-10 years.  After that production falls sharply and new wells need to be drilled and fracked.  We are literately drilling hundreds of new wells every year now to just keep up with current demand.  How much can we push more consumption into energy production before the system breaks?  This winter we saw significant spikes in natural gas prices and restrictions on the use of propane due to weather.  Is this the future we we have to look forward to or were these spikes and shortages only the result of poor planning?  Can anyone imagine what will happen when we start exporting billions of gallons of liquefied natural gas? When our current glut of natural gas is gone what will take its place?      

“Very few analysts believe renewables generation beyond 50% is practical, so we’re stuck with 50% fossils – for how long? 50 years? 100 years?”.

It would be unwise for anyone to think that solar is the complete answer to our energy needs given our current inability to store energy.  Here is a quote I sometimes use to show just how wasteful America has become.  

“According to an updated analysis published last month by the Lawrence Livermore National Laboratory suggests that the USA is just 39% energy efficient.  Put another way, more than half (i.e. 61%) of the energy that flows through our economy is ultimately wasted.”. 

Seems to me that a good place for us to start some type of discussion would be to address this “61%” waste.  Here is the link to the article.

So Bob what do you think the future energy picture of America might look like?  More wind, water and sun or more fossil fuels which are a limited resource?  How about more effort to improve  efficiency or more nuclear?  Less consumption or less population?  Smaller cars or smaller electric cars powered by something other than oil?    

Let’s talk.

Keith Pickering's picture
Keith Pickering on Jan 29, 2014

You’re forgetting the access road, which every wind turbine needs for maintenance. Assuming 5 meters wide and an average 800 meters long, the total wind footprint comes in at 4400 m² per turbine. And of course, there is not one 8MW onshore wind turbine in the world today. In Denmark, the average grid-connected turbine is less than 900 KW. That makes wind’s actual density 0.2 KW/m², or ten times less than nuclear.

And you’re right, no uranium mines for wind. Just five to seven times more steel, aluminum, and concrete per MWh generated. All of which require mining.

Thomas Garven's picture
Thomas Garven on Jan 29, 2014

Hi Keith:

First to answer your questions.

1. “you don’t see a problem with that”.  Well yes I would love to see a carbon free grid.  But given todays technology I also have to be a realist.  There are limits to how much we can manufacture, install and how much capital we want to dedicate to energy.  My guess is that the biggest barrier or missing piece is energy storage.  We are making some progress in that area but we still have a long way to go.

2. “So how do we make those existing …”  At the present time the conversion of coal fired power plants to some other form of heat like Small Modular Reactors doesn’t seem to be in the cards.  We currently seem to prefer the least expensive approach which is their conversion to natural gas. and;

3. “Show me how to build a 100%…”.  Well my best GUESS is that we are probably about 30-50 years away from that possibility and it would involve crossing a lot of barriers:

A. Political will,

B. Technology advances,

C. A new generation of people focused on the value and conservation of energy,

D. Cost effective solutions for each section of the country, and;

E. About 21 more letters of the alphabet of barriers we would need to cross, LOL.

At the age of 73 I will never see this day come and neither will my son and daughter.  It is possible however that My grand-daughter might see a carbon free grid but then it all depends doesn’t it?

Good questions one and all.  Have a great day.

Thomas Garven's picture
Thomas Garven on Jan 29, 2014


Your scolding is noted.  

It has never been nor will it ever be my intention to diminish the value of anyone’s postings.  I sincerely enjoy every one of her postings and respect her area of expertise. 

Bas Gresnigt's picture
Bas Gresnigt on Jan 29, 2014


“…At the age of 73 I will never see this day (100% renewable) come..”

Not so pessimistic.
In Denmark the wind turbines deliver now ~35% of all electricity. At some days even 100%:

They target 50% by wind turbines in 2020. And 100% renewable regarding all electricity in 2040.
100% renewable regarding all energy in 2050.

Since 2013 you only get a license to build a house if you show that the house is 100% energy neutral!

Paul O's picture
Paul O on Jan 29, 2014

I re-read my comment and saw nothing rude. I still dislike double-speak.

Intermittent is intermittent, Variable is variable..English Language is English language.

Paul O. and paulbee  are my pen names, I’ve used them for many years. I sign my work at the office with Paul O, and I see no reason to change a decade old practice.

Bas Gresnigt's picture
Bas Gresnigt on Jan 29, 2014


Denmark will have that 100% non-fossil grid in 2040. They are now at ~45% (~35% by wind turbines).
I only know detail from Germany.

German target is 80% renewable in 2050. That road is clear as with the new low temperature burning circulating fluidized bed power plants, utilities can burn mixes of waste, biomass and also coal, etc.
That fills the gaps when wind+solar fail and pumped storage is empty (Germany has only 35 small pumped storage facilities).

For 90% or 100% renewable, different solutions are discussed.

  • Install 3 2GW (=6GW) cables to Norway. Norway has enough mountain lakes in uninhabitated areas to cover all pumped storage demand (Statkraft would be happy).
  • Power-to-gas (natural gas) conversion. That gas can be stored in our big (Netherlands) gasfields which are near the border.
  • Use existing gas storage facilities in Germany. Bayern has already facilities for 32TWh, which cover a few months of their electricity use.
  • Use power-to-fuel conversion. BMW has a 2MW pilot producing car fuel. Fuel is more easy to store
  • Use batteries. Last summer Germany started a subsidy program for small rooftop solar owners to install batteries. Seems to become a succes. The hope is that the mass production/consumption will bring the costs down (the same way as with solar).
  • Extend the grid with long distance connections to Spain/Portugal.
    If the wind does not blow in the north, it blows in Spain/Portugal. Spain/Portugal already have big amount of wind turbines 
  • Long distance connections to Greece. Greece has offfered to install major solar facilities (also wind turbines), and the sun shines there in the winter tooo (starts also an hour earlier). 

The German Agora has calculated that grid extensions (Norway, etc) are probably the cheapest solution. No decisions made, as it is not necessary to reach the 80% renewable target in 2050.
I assume a mix of these solutions will be chosen (Germans are careful, so they don’t put all on one card).



Bas Gresnigt's picture
Bas Gresnigt on Jan 29, 2014

Here building an access road is avoided as it is too expensive (destroys profitability). So wind turbines are either placed at existing roads or they use four (and n-) wheel drives which drive through the land.

The Enercon E126 7.5MW, is purely designed for the onshore sector.
Agree it is not full 8MW, but I over-estimated the footpring with 20x20meter at least a factor 2.

Turbines below 2MW are antiquated.

Not sure whether such 7.5MW turbine uses more than 100 times the steel that a 750MW NPP uses.
Except the tower and the nacelle, all is from fiber. 
Anyway that steel is one time, while the uranium is used up and has to be produced all the time.

Keith Pickering's picture
Keith Pickering on Jan 29, 2014

So you’re saying that instead of building wind turbines in the windiest places, we should only build them in the roadiest places? Are you aware of what that would do to (the already low) capacity factor for wind, and hence the cost? And if access roads ruin the profitability of wind, why does every existing wind farm have them?

If you look at any wind farm on Google Earth, you will find that the 200 m² turbine footprint you originally cited was about right, and not off by a factor of two.

Finally, according to the analysis of Weissbach et. al. 2013, a 1340 MW NPP uses 93.617 tonnes of iron and steel. At a 90% capacity factor, that’s 78 tonnes per full-time Watt. The same source puts a 1.5 MW wind turbine at 250.127 tonnes of iron and steel. At a capacity factor of 30%, that’s 556 tonnes per full-time Watt: about seven times higher than nuclear.

Going to larger wind turbines actually makes things worse for wind in that regard, because the power in the wind scales by the square of the rotor diameter, while the mass of the turbine scales according to the cube of the rotor diameter. Thus increasing the 1.5 MW turbine by a factor of 5, to 7.5 MW, increases the mass of the turbine (including its iron and steel) by a factor of 5^(3/2)=11. Which makes things twice as bad for wind.

Joe Deely's picture
Joe Deely on Jan 30, 2014


“I’m assuming CA will continue to grow”  – Population will continue to grow but utility-provided electricity has probably peaked due to increasing rooftop solar as well as continuing efficiencies. So will be flat to down over the next 35 years.

For a good study on some issues with 50% renewables (no Big Hydro) in CA. Check out this link –

Roger Arnold's picture
Roger Arnold on Jan 31, 2014

Some very good comments, regarding both Herman’s article and the one by Gail that he was trying to rebut, have already been posted.  I won’t reiterate, but I especially concur with Robert Wilson’s comment of January 27.  Gail’s article is flawed, and badly in need of a good answering piece.  Herman’s article isn’t it.  

Most of the technical points I might have made were covered — and better than I could have done — in Schalk Cloete’s comment just above Robert’s.  

One point that I think still has not been clearly made, however, is that wind and solar are fine vehicles for transforming high CF thermal plants into low CF thermal plants.  The plants can’t be decomissioned, because they’re still needed to pick up the slack during periods when wind and solar are under-delivering.  Their reduced but irregular operating hours do nothing for their fixed costs, and they actually increase O&M costs.  So Gail was quite correct is saying that the actual value of intermittent renewables, in LCOE terms, is limited to the cost of displaced fuel — a few cents per kWh. Any time a utility is required to purchase their output for more than that price — which is virtually always — it is raising the overall cost of electricity to all grid customers.

That’s not to say that we shouldn’t be doing that.  Fossil fueled plants incur major external costs that are not presently captured, and displacement of fuel is worth more than just what the power plant operator pays for it.  But we shouldn’t be kidding ourselves about what we’re doing and what it’s costing.  As Schalk has noted elsewhere, new wind and solar installations are extrememly expensive options, in terms of net cost per ton of avoided CO2 emissions.

One wild card to toss in: I think there’s a very real chance that all our calculations about the cost of intermittency and of coal vs. natural gas are about to be thrown into chaos.  I’ve long felt that the extreme low gas prices that the US and Canada have been enjoying thanks to the “fracking boom” are aberations.  There are signs that the investment craze that has sustained them is beginning to unravel.  The super-fast decline rate for fracked wells coupled with a decline in active rig counts just as new demand is coming online looks like a train wreck in the making.  For long range planning, I wouldn’t count on NG being at less than $10 / million Btu by the end of this year.  It could easily go higher.  What do you suppose *that* will do for backing intermittent renewables?

Kevon Martis's picture
Kevon Martis on Jan 31, 2014

I understand LCOE quite well. And as EIA reports, one cannot make direct comparisons between dispatchable and non-dispatchable generators because of the substantial differences in production profiles.

Of course, neither do average LCOE numbers take into account the profound differences in fuel supply (wind) and the impacts it has upon installed costs (more expensive low wind turbines, e.g.).

In Michigam installed costs for wind run between $2,200-2,500/kw.

In IA they are as low as $1,650/kw. Yet IA’s wind resource has twice the available energy per turbine location relative to MI or OH.

My statements stand: if one does not ask where and when, discussions of relative LCOE between wind/solar versus fossil or nuclear are erroneous and misleading.


Clifford Goudey's picture
Clifford Goudey on Feb 1, 2014

Keith, those roads serve other purposes including recreational access, fire fighting, logging, etc.  Besides, if you want to go down that path let’s start counting the roads and highways needed to transport the components and materials associated with building a nuke.  Also, how do you suggest we count the exclusionary buffer around such a facility or the 10-mile no-escape zone.

Clifford Goudey's picture
Clifford Goudey on Feb 1, 2014

Sure Kieth, but those tons of steel in a wind turbine can be recycled at the end of it’s lifetime and does not need to buried and garded for 10,000 years due to radioactivity.

Contrary to your conclusions, larger, taller wind turbines win in every respect due to increaded efficiency and better winds at higher rotor heights.

Bas Gresnigt's picture
Bas Gresnigt on Feb 1, 2014


“a 1340 MW NPP uses 93.617 tonnes of iron and steel”
“The same source puts a 1.5 MW wind turbine at 250.127 tonnes of iron and steel.”

This assumes that this small wind turbine uses >2times more steel than an NPP.
Clearly not true.

Seems your source cannot calculate well.

Bill Storage's picture
Bill Storage on Feb 2, 2014

You say the first mistake in Gail Tverberg’s piece is using the outdated term “intermittent” for renewables instead of the “more accurate” term, “variable.” 

In what way is variability more applicable to renewables than is intermittency? For some, “variable” may be more desirable, because of the negative light cast on renewables by their having been called intermittent, which they undeniably are. A valid argument might be that the intermittency is an acceptable cost given the benefits of renewables. But that doesn’t go without saying; it is exactly judgment Tverberg has cast doubt upon. The term “variable” in no way asserts with any force that renewables can be managed by grid operators.


Insistence that opponents use the sanctioned language of the group underscores the groupthink inherent in renewable energy advocacy.  Divergence from the party line is regarded as negative, as apparently is departure from the party vocabulary. Curbing CO2 emissions and promoting sound energy policy is serious business. But honesty needs to trump optimism; and appeals to solidarity are misplaced. Bad ideas thrive in cultures of groupthink.


Bill Storage's picture
Bill Storage on Feb 2, 2014

You say the first mistake in Gail Tverberg’s piece is using the outdated term “intermittent” for renewables instead of the “more accurate” term, “variable.” 

In what way is variability more applicable to renewables than is intermittency? For some, “variable” may be more desirable, because of the negative light cast on renewables by their having been called intermittent, which they undeniably are. A valid argument might be that the intermittency is an acceptable cost given the benefits of renewables. But that doesn’t go without saying; it is exactly judgment Tverberg has cast doubt upon. The term “variable” in no way asserts with any force that renewables can be managed by grid operators.


Insistence that opponents use the sanctioned language of the group underscores the groupthink inherent in renewable energy advocacy.  Divergence from the party line is regarded as negative, as apparently is departure from the party vocabulary. Curbing CO2 emissions and promoting sound energy policy is serious business. But honesty needs to trump optimism; and appeals to solidarity are misplaced. Bad ideas thrive in cultures of groupthink.


Kevon Martis's picture
Kevon Martis on Feb 2, 2014

And once more.

Kevon Martis's picture
Kevon Martis on Feb 2, 2014


Kevon Martis's picture
Kevon Martis on Feb 2, 2014

Excuse repeats. The “save” page would not respond.

Kevon Martis's picture
Kevon Martis on Feb 2, 2014

“Keith, those roads serve other purposes including recreational access, fire fighting, logging, etc”

Nonsense. Not in the Midwest. They serve one or two turbines while fragmenting land and reducing crop yield. They also lead to turbines that emit substantial noise pollution thus makeing thousands of square miles unfit for human habitation.

Kevon Martis's picture
Kevon Martis on Feb 2, 2014

In rough terms wind requires ~3x the steel per MW nameplate relative to nuclear.

But wind plants last only 1/3 as long.

And typically their CF is one third of nuclear.

Thus wind requires ~27x the steel per MWh.

This is one of many reasons wind booster’s suggestions that wind’s LCOE cost trends are perpetually downward is laughable on the face.

Clifford Goudey's picture
Clifford Goudey on Feb 2, 2014

Right, Kevon.  Bring on the coal plants, then let’s talk about human habitation.

Paul O's picture
Paul O on Feb 2, 2014

Nancy, What Nuclear Industry? Names Please.

Bob Meinetz's picture
Bob Meinetz on Feb 2, 2014

Nancy, one of my favorite aspects of The Energy Collective is that it attracts contributions from everyone – energy activists (a group in which I include myself), academics, publicists, industry reps who admit they are paid, and those who don’t.

In my opinion, certain contributors are given too much blog space with views which are largely repetitive and supportive of a particular industry. Conversely, certain non-profits appear to be posting merely to increase exposure, and widen their donation base. Both techniques muddy the waters.

But the good thing is that you and I can call them out with facts, and demanding external references. Isn’t that more productive than making baseless accusations about a poster’s motives?

Kevon Martis's picture
Kevon Martis on Feb 2, 2014

Your comment reflects the common misperception that wind generation and thermal generation are interchangeable. But they are not.

 AWEA board member E.ON, which operates German transmission grids and also builds wind plants in the US, is succinct:


 “Wind energy is only able to replace traditional power stations to a limited extent. Their dependence on the prevailing wind conditions means that wind power has a limited load factor even when technically available…. Consequently, traditional power stations with capacities equal to 90% of the installed wind power capacity must be permanently online  in order to guarantee power supply at all times”


Bob Meinetz's picture
Bob Meinetz on Feb 2, 2014

Thomas, no doubt we can make great strides by addressing wastefulness and efficiency. The most important goal should be to always make sure we’re getting the most out of every ounce of carbon we contribute to the atmosphere. My main problem with wind and solar is that both create limits below which we can’t effectively reduce carbon. Cutting our  emissions by 30%, if achievable, would be a remarkable accomplishment. In truth it still isn’t good enough.

I hope our future energy picture includes a high percentage of safe, 4th-generation nuclear. With investment, we are 10-15 years from technology which could use thorium – a source with more energy potential than all of the uranium and fossil fuels in the Earth’s crust combined – to generate 100% carbon-free energy. In that same time frame, battery technology is expected to cost 50% less, leading to clean, long-range electric cars and trucks. Even battery-powered shipping would be feasible – container ships could be recharged mid-ocean by nuclear “tugs” operating under international oversight.

Holding thorium technology back more than anything are entrenched fossil interests, and public misperceptions about the relative dangers of nuclear energy compared to the threat of climate change.

Clifford Goudey's picture
Clifford Goudey on Feb 2, 2014

On line, Kevon, but not operating.  Every kWh generated by wind is a kWh that is not generated by fossil fuel. 

Germany plans to build an underwater HVDC cable to Norway to utilize their existing pumped hydro plants to store excess wind power and make it available when needed.  At that point and none too soon Germany can say auf wiedersehen to traditional power stations and their messy emissions.

Kevon Martis's picture
Kevon Martis on Feb 2, 2014

How many tons of unrecycblable carbon fiber waste need to sit in landfills for centuries with wind?

And of course since wind is intermittent, your wind turbines do not obviate the need for nuclear, gas or coal generation. Thus the wind turbines’ lifecycle impacts are additive to coal, gas and/or nuclear. They are not a replacment, absent incredibly cheap storage. And as long as the wind ptc rewards wind operators for generation irrespective of the demand curve there is absolutely no financial incentive to pursue storage.

Kevon Martis's picture
Kevon Martis on Feb 2, 2014

“Every kWh generated by wind is a kWh that is not generated by fossil fuel.” Not true. It is likely a .8 or .9 factor in most grids. Spinning reserves typically increase as renewable penetration grows.

And I am guessing you would have to flood all of Norway and more to begin to offer anywhere near the requisite amount of  storage.If there is adequate hydro capacity extant in Norway now, then they should just build the transmission and scratch the wind and solar altogether.

I am willing to bet you $100,000 that Germany will NEVER close all their thermal plant in this century.

Further, I hope they continue trying: the more the Germans abandon nuclear in exchange for solar and wind the more likely heavy industry is to flee and relocate in the US with it’s abundant gas.


Bob Meinetz's picture
Bob Meinetz on Feb 2, 2014

Clifford, what happens in protracted spells where the wind doesn’t blow, and Germany runs out of Norwegian pumped hydro? The entire country shuts down until the wind decides to blow again?

Do you realize how many wind turbines it would take to provide Germany with 100% wind power even in optimal conditions? What if we erect these (thousands of) wind turbines, and Germany instead is forced to rely on even more coal generation – a trend which has already been established with the little wind and solar Germany is already capable of generating?

Has Merkel set aside funds to tear down, or “decommission”, all of these turbines if they don’t work as enthusiasts optimistically hope they will?

Joe Deely's picture
Joe Deely on Feb 2, 2014


Just wondering – do you think same entrenched interests will be able hold thorium technology back outside of the US? 

After all, the US will be be playing much less of a role in global CO2 emissions in near future.(10-15 years) 

I believe battery technology will improve even more than your “50% less” in the 10-15 year timeframe you mention. 

Clifford Goudey's picture
Clifford Goudey on Feb 2, 2014

Bob & Kevon – too narrow, see above.



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