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Renewables Growth: Ignoring The Whole Equation

Renewables and Feasibility

When discussing the growth of renewable energy there are two rather common mistakes. First, thinking that the capacity of a renewable power plant is directly comparable with that of a fossil fuel or nuclear power plant. Second, thinking that energy consumption and electricity consumption are the same thing.

The first mistake can lead to incredibly uninformative headlines. “New renewables capacity greater than fossil fuel capacity,” and so on. Now, what do these headlines mean? A typical one gigawatt fossil fuel power plant will run at around 60% capacity factor, that is it will average around 0.6 GW in output. 1 GW of solar can average anywhere from 0.1 GW in Germany to 0.2 GW in Arizona. Onshore wind also varies significantly. The United Kingdom has the highest average capacity factor in Europe at 27%, while in Germany it is around 18%. Clearly we are not looking at apples to apples comparisons

And we can even be looking at order of magnitude differences. Nuclear power plants have low running costs, so typically they run as often as possible. US average capacity factor is 90%. This is almost ten times higher than German solar. I have memories of energy “experts” informing us in the wake of Fukushima that Germany was building 7 nuclear power plants worth of solar each year. One must ask how such people can be deemed experts, and invited on to the television to provide on demand punditry.

The second mistake is equally common. A rule of thumb: if a news story has a headline along the lines of “Scotland targets 100% renewable energy by 2020”, what it really means is that Scotland targets 100% renewable electricity by 2020. The difference is significant. The majority of energy consumption is not in the form of electricity. We need to drive, fly, heat our homes, produce steel, cement and do a variety of other things with oil, coal and natural gas. The central reason to switch to renewables is because of climate change, and reporting renewables penetration only in terms of electricity is to miss the whole equation. Yet people continue to do it.

How much can stating renewables growth in terms of capacity, generation of electricity or energy consumption make a difference?. Quite a lot. Here I will consider global growth of wind and solar in 2011 to illustrate the point.

Looking first in terms of capacity, using EIA’s data for installed capacity. Total installed global electricity capacity increased by 245 GW in 2011, from 5085.6 to 5331 GW. Of this increase, 41.3 GW was in wind, and 29.5 GW was in solar. In other words 29% of the increase in global electricity capacity was in wind and solar. Not too bad.


We can then move things things up a level, and think about electricity generation. According to BP global electricity generation increased by 646.4 terawatt hours in 2011, from 21,404.5 to 22,050.9 TWh. Electricity generation from wind farms increased by 92 TWh, and the increase from solar power was 28.3 TWh. So, 19% of the increase in global electricity generation in 2011 came from wind and solar. Suddenly things are looking slightly worse.


Finally, consider primary energy consumption, that is all of the energy we consume. BP state that global primary energy consumption increased by 281.6 million tonnes of oil equivalent (Mtoe) [a caveat: BP does not count biomass burned in Africa and Asia, but this is a minor detail]. Of this, 20.8 was from wind and 6.4 Mtoe was from solar. So, about 10% of the increase in primary energy consumption in 2011 was from wind and solar. And for 2012, the figure was only marginally higher.


These simple comparisons show that we need to be very careful about how we state the growth of renewable energy. They also show that we are not remotely close to seeing renewables replace fossil fuels. There is still close to an order of magnitude difference between new fossil fuels being added to the global energy system and that coming from wind and solar.

Naturally some nuclear advocates will point to this and show how ineffective renewables are. So, I will close with a graph of how much global primary energy consumption has increased since 2000, and how much nuclear energy consumption increased, or more accurately decreased.


The reign of fossil fuels is not ending any time soon.

Robert Wilson's picture

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donough shanahan's picture
donough shanahan on February 11, 2014

I made a comment on the Guardian website recently along those lines. As a quick rule of thumb guide it does gove some good insight as to how wrong these 100% renewable claims can be. In short

Renewable energy sources account 4.1% of energy consumption UK. Electricity is the easiest area to look at. In 2002 renewable sources of electricity accounted for 3% whereas in 2012 it reached approx 12%. That is about 1% per year so unless the growth rate increases drastically, it would take quite a while for a renewable grid to come online assuming all other hurdles are overcome.

Now growth rates at the the end of the curve are higher but even at 2% per year, it is still a long period of time before we start to approach a ‘green’ grid.

Ed Dodge's picture
Ed Dodge on February 11, 2014


I fully agree with your analysis.  Renewables advocates routinely overstate usage by discussing capacity instead of production and by using the word energy when they mean electric power.

Fossil fuels are not going away anytime soon, if ever.  And even if we do eliminate fossil fuels we will still use hydrocarbons.  I don’t see any molecules that outperform hydrocarbons in cost, performance and availability and they are irreplacable for certain tasks.

So the question is, what is to be done about this situation so we may avoid polluting ourselves to death or overloading carbon in the atmosphere?

Schalk Cloete's picture
Schalk Cloete on February 11, 2014

Good analysis.

Another slightly different way in which to say the same thing is to estimate the rate at which wind and solar power will need to be installed in order to sustain the capacity needed to provide 100% of global energy consumption (around 17 TW). If we assume an average 25 years lifetime with no degradation for wind and solar operating at an average capacity factor of 20%, the world will need roughly 17000 GW / 0.2 (CF) / 25 years = 3400 GW/year of solar and wind installations. If we can do this, we can convert the global economy to 100% solar and wind in 25 years. 

For perspective, combined wind and solar installations in 2012 were 75 GW. Thus, to go to a 100% wind/solar utopia, we need only to increase the deployment rate by 4500% and maintain that deployment rate for 25 years. As easy as that… 

John Miller's picture
John Miller on February 11, 2014

Another factor or variable “ignored in the whole equation” is the required fossil fuel and hydro backup power required to maximize wind & solar power generation capacity factors (net generation / design capacity).  Wind & solar power generation capacity factors are often maximized by giving these variable/unreliable renewable power generation sources priority power grid supply-connection over all other power generation supply sources.  As you are aware, to control power grid’s supply-demand balances and overall reliability requires backup, intermediate/peaking power generated by ramping-up/-down fully controllable power generation from hydropower, fossil fuels and some nuclear plants.  The end result further makes renewables look better than possible without the largely fossil fuels backup power.  This maximizing wind & solar capacity factors operation (often mandated by governments) also directionally reduces all other power generators capacity factors & efficiencies, used to maintain overall power grid reliabilities 24-7.

Robert Wilson's picture
Robert Wilson on February 11, 2014


This is a key issue, and one I covered a few months back. Currently there is little need to curtail wind or solar. However as you increase their penetration you will need to do this more and more.

So you could argue that you need to compare total solar or wind capacity with the capacity required to meet say 50 or 70% of demand.

A country with average demand of 100 GW might need 50 GW of solar for 10% solar. You can just run the solar panel 24/7. But if you wanted 30% solar, you might need 4 or 5 times more solar capacity because of curtailment etc, not three times more.

Quantifying that is very tricky because it is very dependent on how storage technology pans out.

Robert Wilson's picture
Robert Wilson on February 11, 2014


Another key issue. Again, the Germany situation is very informative. They are opening 11 GW of state of the art coal plants this decade. They can obviously last for about 60 years. In contrast the wind and solar can last about 25 years.

So, you could argue that instead of capacity additions we should be looking at projected lifetime TWh from new plants, and compare that with projected future lifetime TWh of all power plants on the grid. That would give us an indication of how quickly things can be replaced at current build and retirement rates. It might be interesting to do that on a country by country basis. Not too difficult to do if you had a database of power plants. But I think none are available unless you pay for it.

This would probably show that there is a lot of variation in how quickly you could replace the existing fossil fuel power plants. China, for example, has built almost all of its capacity since 2000, so replacing this won’t be quick. The UK in contrast has to retire a lot of capacity shortly.

Joe Deely's picture
Joe Deely on February 11, 2014

Interesting analysis – I didn’t realize solar and wind were doing that well worldwide.

It is also interesing if you show data from 2010 and 2012.

Looking at the these years as well as 2011 in data from BP…

2010 – 81.5 TWh(New Solar and Wind) / 1280.8  TWh (Total New Generation) = 6.4%

2011 – 120.3 TWh(New Solar and Wind) / 646.4 TWh(Total New Generation) = 18.6% – as you calculated

2012 – 115.6 TWh (New Solar and Wind) /  453.1TWh (Total New Generation)  = 25.5%

So, 6.4% of increase in WW electricity generation in 2010 came from Wind and Solar, 18.6% in 2011 and 25.5% in 2012 .

Not bad.

John Miller's picture
John Miller on February 11, 2014

And, without successfully developing new industrial scale electric power storage (other than current limited hydropower pumped storage) the maximum feasible penetration level of solar will continue to rely on alternative intermediate/peaking power; primarily fossil fuels.

Silvester van Koten's picture
Silvester van Koten on February 11, 2014

Dear John,

Giving wind and solar priority dispatch should not deviate much from an optimal dispatch as their variable costs are one of the lowest. The dispatch becomes inefficient once the electricity price becomes negative and wind and solar are not allowed (not even against constraint payments) to reduce their output as in Germany (I have understood that the Irish system avoids these dispatch inefficiencies by allowing wind and solar to be constrained).

Regarding your comment of wind and solar requiring fossil fuel backup, I came across an interesting paper by Taylor and Tanton (2012), entitled “The hidden cost of wind electricity”,  written for the  American tradition institute (see: It looks like a decent study and tries to put numbers on the full costs of wind by explicitely acknowledging that installing wind always implies to also support a backup coal or gas plant. As a result, the levelized cost of electricity increases from $80/MWh to about $150-$190/MWh.

The numbers are for US, given their very low gas prices and the relatively low penetration of wind. The costs figures will of course increase with higher penetration of wind along the line of the paper by Lion Hirth (nicely summarized on this bog forum by Schalk Cloete).

John Miller's picture
John Miller on February 11, 2014

Silvester, the impact of variable wind & solar depends on the power grid balance for any given day.  If increased wind/solar results in reducing intermediate/peaking power towards-below minimum operating generation rates, the added costs due to inefficient operations and possible unscheduled-more frequent shutdowns will be very significant.  This is due to the fact that all power plants have ‘bell-shaped’ efficiency and allowable rate operating curves.  When the rates are above or below optimal/maximum efficiency rates, fuel consumption per KWh increases.  If the rates are trimmed below minimum, the backup power unit may be forced to shutdown.  Multiple unscheduled startups & shutdowns directionally minimize efficiency rates (increased fuel costs) and can increase maintenance costs.

Yes, as the penetration level of variable wind & solar increases, the impact on backup power costs does indeed increase.  Thanks for the ATI reference; which appears to be based on reasonably sound data/analysis.

Joe Deely's picture
Joe Deely on February 12, 2014


Trying to get my arms around what you are saying in above. Wondering if you can comment on the below to help me understand.

1)As an example let’s say that Mid-American Energy in Iowa buys subsidized wind at $25/MWh through a PPA with a developer.

“The Midwest of the US is seeing power purchase agreements signed at $25/MWh; exclude the impact of the Production Tax Credit and that is an unsubsidised price of $47/MWh, lower than the levelised cost of a new gas plant, even with the US’s low gas prices.”

2) Are you saying that they will be consuming substantially more coal or gas per kWh because the coal plants are operating inefficiently? If this is what you are saying – any idea on much? 

Also are you saying that as Mid-American wind penetration level moves beyond 30%  – let’s say to 40%  these additional costs “backup power costs” will increase substantially?  which should translate to increased bills for customers, right?

 3) I’ve included some information on Mid-American below-

Our Generation Mix. At the end of 2012, MidAmerican Energy had 8,087 megawatts of owned and contracted generating capacity. Approximately 45 percent was fueled by coal; 30 percent by wind; 19 percent by natural gas and oil; and 6 percent by nuclear, hydroelectric and other.


Residential – $0.0881

Industrial – $0.0430

Retail – $0.0624


Information on wind plans going forward:


Robert Bernal's picture
Robert Bernal on February 11, 2014

We need to convert the subsidies for all the high priced components into just the development of the machines needed to make wind and solar very much less expensive.

We also need a will to mandate the development of closed cycle nuclear and lots of pumped hydro storage or better.

Nathan Wilson's picture
Nathan Wilson on February 11, 2014

Don’t forget about the global economic slowdown, the economies (and therefore electricity demands) of most countries outside of China where not growing, so very little new firm capacity was needed.  The solar and wind largely was installed as money-losing economic stimulation.

Nathan Wilson's picture
Nathan Wilson on February 11, 2014

Granted, ignoring sustainability and environmental impact, fossil fuels are the best energy sources and energy carriers.  However, the second rate energy carriers, hydrogen and ammonia, along with the expensive but highly versatile electricity are good enough for most purposes (i.e. something like 90% of energy applications).  Changing to these energy carriers would certainly require a lot of expensive new infrastructure and decades of transition.

We certainly might choose to continue business as usual while we await a breakthrough that makes fossil fuels obsolete.  Or we might choose to pay extra and endure a little inconvenience to switch to fuels that are actually sustainable and minimize environmental harm. 

And energy-cost-wise, the world is not homogeneous.  The price of petroleum is about the same everywhere, due to low cost shipping.  But nuclear power varies by a factor of 3x around the world, so by my calculations, the giants of future energy use (China and India) could, if the technology were widely deployed, make H2 or NH3 from nuclear power for a cost which is in the ball park with imported gasoline (perhaps someday solar fuels will catch up too, but not today).

Wealthy nations like the US are slow-tracking development of nuclear-hydrogen production because we would rather work on things that will turn a profit next year.  Unfortunately, the road to short term profits does not always lead to our long term goals.

Kim-Mikael Arima's picture
Kim-Mikael Arima on February 11, 2014

A third issue, that cuts very close to the comment by Schalk, is the lack of understanding of time scale when it comes to changes in energy patterns. One of Robert’s favorite sources, Vaclav Smil, has written about this at length. 

Many people think that the mere fact that “a revolutionary solar-hydrogen residential power package solution” is being studied at MIT means we’ll have this thing sorted by 2020. Or one of the “dozens of promising battery technologies” being studied in universities around the world will be commercialized and deployed on a global scale to take care of the backup needs of a 100% renewables power system. Or that the one tidal power technology that actually managed to get a pilot running in 2012 will turn into hundreds of gigawatts of tidal power capacity by 2030 and save us all (never mind that we need thousands of GW, not hundreds).

The first 1 MW wind turbine was erected in the 1940s. Solar cells were first manufactured in the 1950s. Anything that’s not commercial today is highly unlikely to transform the energy system by 2050, let alone 2030.

Robert Bernal's picture
Robert Bernal on February 12, 2014

Dealing with closed cycle nuclear would be intrinsically less expensive than dealing with ccs. 6 orders of magnitude of wastes confinement. Better yet, the fission products need to be vitrfied in glass and are no longer radioactive in a few centuries, whereas the many billions of tons of CO2 will probably leak back into the biosphere within that time.

The development will be in autonomous machinery that will make solar and wind and storage less expensive, which can deal with nasty fission products and can more efficiently extract the elements needed to build whichever is the best.

Joe Deely's picture
Joe Deely on February 12, 2014

Actually if anything I cherry-picked by using 2010 vs 2009 as that was the largest growth in both absolute and relative electricity growth over the last 27 years(data starts at 1985) with relative growth at 6.4%.  Average for this time period was 3.1% growth.  2009 vs. 2008 had slightly negative growth, hence the backlog for 2010.

In absolute terms the average growth was 465TWh over this time period so last three years are pretty indicative of trend.

As for the “money-losing economic stimulation” it looks that is set to continue as IHS has predicted continuing double-digit growth in solar for 2014 – with 40-45 GW installed.

Nathan Wilson's picture
Nathan Wilson on February 12, 2014

Not to worry Joe, electrically speaking, Iowa is just a small part of a much larger electrical system, the Midwest ISO (see this presentation as an example of their transmission planning).  

According the the DOE 2012 Wind Technologies Market Report, Iowa generated 25.3% of its electricity from wind power, whereas its near electrical neighbors had much lower wind penetration:  Minnesota: 16.9%,  Illinois: 4.8%, (Wisconsin and Missouri are both below the 3.7% cutoff on the list).

So if Iowa keeps building wind power and new transmission (such as this transmission project) you’ll be able to boast of a very high wind percentage of your electricity from wind power.  But you won’t have blazed a trail for others to follow, as the hard part, handling the variation in high penetration wind, will be largely done for you by your neighbors (who will ramp their fossil fuel generators up and down with your wind fluctuations).

Silvester van Koten's picture
Silvester van Koten on February 13, 2014

John, yes you are right. These balancing costs are an externality that should ideally be priced in by charging intermittent generators for being out of balance.

I have understood, though, that these balancing effects are still relatively small. Hirth (2013), basing his approximation on a literature study, uses a (fixed) estimate of E4/MWh as balancing cost. Profiling costs seem to be the major driver of Hirth’s results.

Also, Denny & O’Malley (2005) find in Ireland for penetrations of wind of 3% of installed capacity that savings in carbon emissions are about 20%-30% lower due to balancing effects. This is, of course, a considerable effect, but indicates claims that intermittent renewables may increase carbon emissions are exaggerated.

Then again, these costs may of course increase with penetration levels. The two studies I mention above do not take this in account. Anybody knows of any decent studies on the effect of penetration on balancing costs?

Alistair Newbould's picture
Alistair Newbould on February 13, 2014

We frequently seem to get into this discussion of storage and back up for renewables but I haven’t yet seen anyone comment on load management

until quite recently New Zealand hot water heaters were controllable by the electricity supply companies using ripple control (see midway through the above wiki article) to curtail demand side. this takes the peak off the top of demand making renewable penetration much easier. There is a massive amount of “storage” of energy n all the hot water cylinders in homes and businesses and ripple control effectively makes use of this as a storage mechanism – using low peak electricity to heat the water and forbid use of high peak electricity for heating water.

What about off peak power pricing – is that still used? Two meters in your house one on a lower rate but only available at off peak times. Using timers you run the washing machine at night, nite store heaters – anything that can be put off to another time of day. As I have previously posted deep freezers can store energy in a similar way. All of this could be put in place very quickly at reasonable cost.

Change our ways now or Gaia will do it for us.

Nathan Wilson's picture
Nathan Wilson on February 13, 2014

This is understandable since the technical challenges for them [the emcumbants] to do so with their legacy kit appear insurmountable. … Nuclear can do the job but it has yet to manage its risks of cost and schedule overruns, and can only promise very expensive electricity for the next 50 years.

This does not match the available data.  Technically, nuclear works fine.  With today’s nuclear technology, the safety is much better than any alternative (even renewables with fossil backup), the dispatchability is adequate for high grid penetration, we have viable ways to store the waste (dry cask storage and the WIPP underground facility are proven safe and economical), and the sustainability of supply is adequate for over a century with LWRs and indefinitely with breeders.  

Nuclear power has serious challenges due to political unpopularity, largely because the environmental movement of the 1970s chose to align with the fossil fuel industry and lobby against nuclear power (which effectively saved the coal industry in the US, much to the detriment of the environment).

As to the alleged high cost and schedule overruns of nuclear, yes the initial cost is high, which runs counter to private industry’s preference for short-term profits.  Cost over-runs are part of any first of a kind project.  But even so, today’s nuclear power plants still deliver initial energy cost which is competitive with other very-low-carbon energy sources, and deliver long-term fleet average costs which are better than clean alternatives; when measured at grid penetrations above 60% even the initial economics of nuclear are much better than clean alternatives.

The frequently stated notion that nuclear power uniquely has a negative learning effect is absurd.  Yes costs went up in the early days due to first-of-a-kind effects.  But no credible industry experts believe future costs will go anywhere other than down as the new designs are built in large numbers.  (Yes, I know, the renewable movement has its own set of experts with their own data and their own version of reality;  does no one see a problem with that?).

The beloved notion that distributed renewable generation is somehow more economical than (and destined to replace) renewable (or nuclear) generation by central utilities is also the opposite of what we see in the real world.  Yes, utility rate structures will have to change to properly allocate costs among energy users, but utility-scale renewable generatation is still the least cost method.

Joe Deely's picture
Joe Deely on February 13, 2014

Nathan, Thanks for the comments and the links – I hadn’t seen the DOE2012 report before.

I am familiar with MISO – I was trying to keep the example simple. Perhaps, I should have chosen Texas – ERCOT.

However, the main question was really – How much does additional wind generation “cost”? In an earlier comment the following was said. 

“The added costs due to inefficient operations and possible unscheduled-more frequent shutdowns will be very significant.”  

Within a huge system like MISO – with its hundreds of available resources, wind forecasting and 5 minute scheduling is this really a valid statement? I certainly see no indication of it in my readings. In fact, there are many comments within MISO about how to bring low-cost wind into the mix.

Here is a comment from Mid-American regarding their next wind expansion:

“The expansion is planned to be built at no net cost to the company’s customers and will help stabilize electric rates over the long term by providing a rate reduction totaling $10 million per year by 2017, commencing with a $3.3 million reduction in 2015.”

Granted – these lower costs are at least partially being funded by PTC – are you also saying that Iowa is passing on costs to its neighbors – Ilinois and Wisconsin and the rest of MISO in the form of increased fossil fuel costs? If so, any idea how large? 


Silvester van Koten's picture
Silvester van Koten on February 13, 2014

The main reason for the hefty cost increase of nuclear, sometimes referred to as the cost curse”, seems due to regulation. The late Bernard Cohen has an interesting chapter on the cost curse in his book “The nuclear energy option”. He gives a fairly detailed account of the costs involved in building a nuclear plant and states that “regulatory turbulence” has had a major influence on cost increases and that it may have caused, in some cases, paradoxically, less safe plants.

Regulatory turbulence refers to the unpredictable arrival of new regulations. As new regulations also apply to plants being built, they require the designers to change the design while building. Apparently, such adaptations, when applied while building, cost a multiple of the expense involved in implementing them into the design before building.

 In a very recent report, D’haeseleer comes to estimates of levelized costs of nuclear energy for new plants, including externalities, of 34-41/MWh (and these are the numbers on the most pessimistic end). 




Joe Deely's picture
Joe Deely on February 13, 2014

I am wating for the day when I see the following:

“Independent Power Producer First Nuclear (fake name) has secured $800M in financing for a new nuclear project in West Texas. The project will provide 200MW of energy and the output will be sold to Austin Energy as part of a 20 year PPA (Power Purchase Agreement)”

Until we start seeing headlines like this nuclear will be a small player in any new generation.

Robert Wilson's picture
Robert Wilson on February 14, 2014


Ultimately decarbonisation of the global economy will involve decarbonisation of electricity and electrification of as much as possible. I remain doubtful that any biofuel should provide a significant portion of energy consumption. This essentially leaves us with electricity. Storage will obviously have to play a fundamental role. Other than trains direct use of electricity in transport is a non-starter. Electricity still has limits. Can we use electricity for aviation, shipping, or steel production? Electricity is also likely to be expensive for many applications, in particular those were we currently use natural gas. 100% electrification would probably require nearly unthinkable breakthroughs in both storage and cost of nuclear or renewables.

Bob Meinetz's picture
Bob Meinetz on February 14, 2014

Robert, you write:

Other than trains direct use of electricity in transport is a non-starter.

I’m not sure where you place the explosion of EVs in this assessment, but with Li-ion batteries prices expected to drop 66% by 2020 electricity is not only starting, but revolutionizing transport.

While electric aviation/shipping will probably never be practical, there isn’t much else which can’t be electrified given a robust source for the electricity. Nuclear has been providing that source for thirty years in France, and rates are currently half those of renewables-heavy Germany.

The only breakthrough required is one of public perception.

Robert Wilson's picture
Robert Wilson on February 15, 2014


I said “direct use” of electricity, i.e. non-stored electricity.

And I don’t see how electric cars are revolutionising transport. This is just wishful thinking, and not backed up by evidence. I don’t see how a luxury car getting favourable reviews by Consumer Reports as a revolution. Some saliant facts. Obama said the US should have 1 million EVS on the road by 2015, not going to happen. Germany has a target for 1 million EVs on the road by 2020. What are they are doing now? Considering revising the target down to 0.1 or 0.2 million, and re-defining the target to include hydrids. This is not a revolution.

Gary Tulie's picture
Gary Tulie on February 15, 2014

Excellent point. There are four ways to ease ballancing of intermittent renewables – not just back up power plants and energy storage. 

The other two methods are 

Demand side management

Hot water, movement of potable water to distribution reservoirs, generation of pure gases (oxygen, liquid nitrogen, CO2 for fire extinguishers) control of larger refrigeration and air conditioning plant, and heat for district heating systems, and charging of electric vehicles. All this list are “dispachable” to varying degrees i.e. can be preferentially carried out to a greater degree when the sun shines, or the wind blows, and backed off when there is a surprise reduction in intermittent generation.

Note:- The comment regarding large air conditioning / refrigeration referrs to thermal inertia in large systems wherein the plant can be turned on or off for possibly 20 to 30 minutes with minimal temperature change.

Geographical averaging across an improved grid

Improved grid interconnection combined with wide distribution of intermittent renewables, and some selective orientation of solar arrays towards the west to shift peak production can allow a higher overall penetration. Peak wind / solar production is unlikely to occur simultaneously over a large geographical area. i,.e. you are unlikely to get gale conditions in New York, the mid west and California simultaneously. Geographical averaging chops off a large proportion of the peaks and troughs making the renewable contribution more even and predictable overall as compared to huge penetration in one local area.

Gary Tulie's picture
Gary Tulie on February 15, 2014

Battery electric cars can eventually play a major role in enabling far higher penetration of intermittent renewables as providing a vehicle has enough charge to meet the driver’s needs, it matters little whether the battery gets charged up at 4am or 4 pm. 

Most vehicles are parked up >90% of the time, so it will be relatively easy for many vehicles to take their charge when the grid is most able to provide it. Indeed, if the vehicles have sufficient capacity, and the batteries are robust enough to give sufficient charge cycles, there is no reason why such vehicles cannot deliver peak shaving services when the grid would otherwise be under stress with unsufficient capacity. 

Regarding shipping, whilst only nuclear propulsion is likely to deliver a complete removal of fossil fuel use, zinc slurry fuel cells, kits sails, and to a limited extent PV could potentially reduce their use quite significantly.

Gary Tulie's picture
Gary Tulie on February 15, 2014

The lowest cost method by far to improve sustainability across all energy use is efficiency. 

Typical European families use around half as much electricity as American families whilst having lifestyles that are not very different in terms of overall affluence. The same goes for vehicle fuel use. Much of this difference is down to efficiency driven by differences in regulations and taxation policy. 

For lighting, removing all use of incandescent light in favour of fluorescent and ultimately LED can drop global electricity use by possibly 10 to 15% as compared to business as usual. Many appliances are made in high efficiency and low cost low efficiency versions. Often there is only a small production cost difference between the two which might be recovered in lower operating costs in a year or two. In such a situation, it is madness that the more efficient design is not made mandatory with a regulatory framework requiring ever greater efficiency in the future. 

Similarly with housing. In Germany many thousands of houses are built to Passivehaus standards and require only a very tiny proportion of the heating and cooling of a conventional building. 

We all need to get very much smarter in our energy use if we are to sustainably enjoy a reasonable quality of life, and lift the poor of the developing world out of abject poverty. 

Robert Bernal's picture
Robert Bernal on February 15, 2014

Just as the nuclear closed cycle should have been mandated, the lifepo4 battery could have been an essential part of our national security or strategic interest. It is slightly less energy dense as the li-ion, but does not have any thermal issues, has about 2,000 charge cycles, and doesn’t require any really rare elements. Developed by a guy named John Goodenough at a lab in Texas, but essentially given to China. Electric car enthusiasts have to buy ’em for high prices but they are still cheaper than the other chemists given the long cycle life.

Nathan Wilson's picture
Nathan Wilson on February 15, 2014

Of course you won’t see that in our lifetime.  The free market is a fight to the death for companies.  The real battle is between fossil fuels and nuclear.  The green movement is just a shallow distraction that masks the real issues (renewables can be a big part of either system, but will reach majority status in neither).  

We know that nuclear will win in the end because the fossil fuels will run out.  Nuclear will win first in countries like France and Japan which lack fossil fuels, and the transition will be last in places like Austin Texas, Australia, and Germany because of the strength of their fossil fuel industries.

Also, the independent power producer (IPP) market structure is designed to boost market share and profits for the fossil fuel industry (with fuel as the dominant cost).  The sustainable electricity industry is a natural monopoly.  Wether it’s a nuclear reactor that lasts 80 years, a hydro plant that lasts 100 years, or a solar CSP installation that lasts 50 years, the costs to the end-user will be cheaper if the plant is owned by a regulated public utility (rather than an IPP that greases the old machine once in a while then marks up the price to match new builds).  

True, power purchases agreements work well for short-lived wind farms at low penetration, but it remains to be seen whether wind can play a role in sustainable electricity, given its dependence on fossil backup and poor compatibility with energy storage.

Gary Tulie's picture
Gary Tulie on February 15, 2014

Wind’s compatibility with energy storage varies dramatically with location and geography as well as the nature of the available storage. 

For a country like Norway with >90% of its power from hydro and substantial water storage capacity, wind is an excellent match – allowing hydro generation to be deferred when wind contributes to demand. In fact, in a situation like this, wind is more compatible with storage than solar given the total absence of winter sunshine in much of the country. Wind can reliably contribute significant amounts of power fairly regularly even if not on a daily basis. (Hydro power is better suited to the variation of weather systems every few days than other storage.)

For a country like Saudi Arabia, solar can provide a very substantial proportion of daytime base load especially with some westerly orientation, and potentially a substantial dispachable “dump load” in the form of reverse osmosis desalination. Any battery storage could fairly reliably cycle on a daily basis allowing solar to contribute significantly to evening peak demand.

Nathan Wilson's picture
Nathan Wilson on February 15, 2014

That’s right, the world’s deserts, using CSP with thermal energy storage, HVDC transmission, and fuel synthesis, could theoretically power the entire world, with substantial room for demand growth.  

Thus far, zero countries have agreed to get the majority of their energy from someone else’s desert (particularly the volatile Middle East).  The US of course, has a domestic desert with excellent solar resources; thus far, zero regions of the US have agreed to import power from the desert southwest, and zero American desert communities have agreed to pave over their “fragile” desert ecosystems to power the energy appetites of the nation.  

Wind (without storage) and its transmission are growing, but the local NYMBY resistance is growing, and wind is still 2 orders of magnitude away from satisfying our energy needs.  Only in the US central planes is low penetration wind cheaper than nuclear, and when storage is included, wind is always more expensive than nuclear.

Thus I conclude that nuclear power, with its production and jobs near the demand centers and small ecological footprint, is uniquely able to replace fossil fuels.

Bob Meinetz's picture
Bob Meinetz on February 15, 2014

Robert, LiFePO4 is one flavor of Li-ion, of which there are at least 16.

Though averaged over the life of the battery they do make more economic sense, carmakers like Nissan and Tesla deliberately chose less durable battery chemistries to keep the initial price as low as possible.

Given public skepticism about EVs it was probably a good decision.

Alistair Newbould's picture
Alistair Newbould on February 15, 2014

Gary, at the risk of starting a mutual appreciation society (following your comment to my post earlier) I have to agree with you. The important thing about this is that it is acheivable by most people now. It does not rely on government or big money. Millions of little changes add up to a very large impact. If we all cut our personal and workplace emissions (of GHGs) by 10% per annum we would have this thing cracked. Perspective – find a different way to get to work one day a week – eg teleworking, ride a bike, car share, and you have cut your transport emissions by up to 20%. These are not difficult things to do and they buy us a lot of time to sort the big picture issues being discussed here.

Here’s another thought. If we need to “buy” time to transition to carbon free energy, planting a whole lot of trees wouldn’t be a bad place to start. Lifespan of 25 years of carbon absorption.

Gary Tulie's picture
Gary Tulie on February 16, 2014

Nuclear costs can quickly escalate when decommissioning, waste management, the cost of accidents, and the true costs of a comprehensive insurance policy are taken into account.

Decommissioning and W aste Costs

Take Sellafield nuclear reprocessing site – decommissioning costs have already escalated to an estimated £70 ($112) billion for just this one site.

The total bill for decommissioning is estimated at up to £100 billion including the UK’s first generation of nuclear power stations.

True, more recent generations of nuclear plant are better designed to facilitate decommissioning, and produce less waste per kWh generated, but the costs are likely to remain high.

In the UK, the government is underwrighting this cost.

Accidents & Insurance

Thankfully, nuclear accidents are rare, and most such accidents are relatively small involving minor releases of radioactive isotopes. When a big accident happens such as Chernobil, Fukushima, or 3 mile island, the costs are huge.

At the present time, to the best of my knowledge, every nuclear power plant on the planet is backed by a government guarantee underwrighting a limited insurance, and carrying the additional risk of a “worst case” accident. 

  • Chernobyl disaster, 1986: $15 billion estimated cost of direct loss. It is estimated that the damages could accumulate to €235 billion for Ukraine and €201 billion for Belarus in the thirty years following the accident;


A private think tank says the accident at the Fukushima Daiichi nuclear plant could cost Japan up to 250 billion dollars over the next 10 years

3 mile island  

Cleanup started in August 1979 and officially ended in December 1993, with a total cleanup cost of about $1 billion.[13] Benjamin K. Sovacool, in his 2007 preliminary assessment of major energy accidents, estimated that the TMI accident caused a total of $2.4 billion in property damages.[76]

Initially, efforts focused on the cleanup and decontamination of the si

Assuming it were possible to get insurance on such a scale, how much do you suppose it would cost to get $500 – $1000 billion of cover per nuclear power station to cover a worst case accident without government underwrighting?


True, all of the above may be at the high end of the cost spectrum, but the real costs are certainly very substantial and cannot be ignored when costing nuclear power. 


Gary Tulie's picture
Gary Tulie on February 16, 2014

Regarding Passivehaus, it is true that the insulation is unusually thick, but that does not result in condensation.

What can lead to condensation is inadequate ventilation. As Passivehaus buildings are very airtight, they need systems of mechanical ventilation in order to remove excess moisture which inevitably arises from cooking, use of water, sweating etc. 

A mechanical ventilation system (MHRV) is not air conditioning, but is far simpler – just a fan and a cross flow heat exchanger. No heat pump is involved. 

To regulate MHRV, a humidistat is usually used to switch between a low level of trickle ventilation and a higher level of ventilation used when humidity rises. The system can be set with an alarm to go off if the fan fails so protecting against the mold problems to which you refer. Such a system is highly recommended in a Passivehaus due to the inability of the house to ventilate adequately with windows closed without MHRV.

The above applies to Passivehaus designs in cooler climates. For the humid tropics, different strategies would be required to prevent mold build up when cooling. 

Regarding your last point that saving energy in Scandinavia does not benefit the people in India in the direct sense, you are absolutely right. Indirectly however, the more widely energy efficient lights, devices etc are used in the developed world, the lower their cost so making them more viable in the developing world, and allowing such people to more easily afford devices such as solar charged LED lights. 

wind smith's picture
wind smith on February 16, 2014

Nathan, please reply to Joe’s February 13 comment about Iowa wind. Being an upper midwest energy consumer, I am very interested in future choices for next generation power especially with how the new EPA CO2 rules will impact those decisions.

wind smith's picture
wind smith on February 16, 2014

John, please reply to Joe’s February 11th – 13th comment about Iowa wind. Being an upper midwest energy consumer, I am very interested in future choices for next generation power especially with how the new EPA CO2 rules will impact those decisions.

wind smith's picture
wind smith on February 16, 2014

Robert, your analysis is very incomplete unless you consider Gary Tulie’s comment on February 15th as to more HVDC transmission, demand response and low temp thermal storage including AC.

Robert Wilson's picture
Robert Wilson on February 16, 2014

“Wind” please state your actual name.

First, do not go around telling people to address other people’s comments. It’s somewhat rude. And if you are going to do it, please make an effort to show how they are relevant. I really do not see why my piece is incomplete unless I address “low temp thermal storage including AC.” Neither am I telekenetic enough to understand why you think this is relevant.

Joe Deely's picture
Joe Deely on February 16, 2014

Interesting comments… sounds like you are talking about the way things were in the 50s and 60s… when we had simple regional utilities which both produced and sold power. This is not the way things are now and defintiely not the way things are moving.  Look at move in PA to have Comcast sell power. Huge changes in this area coming over the next 20-30 years.

Just curious – Would you call Exelon a regulated public utility? I know it has utilities in its portfolio but it is also an IPP.



Bob Meinetz's picture
Bob Meinetz on February 16, 2014

Nathan, you bring up an important point about solving the problem of renewables’ variability by drawing upon sources over a wide geographical area.

Even within an interconnection, state law varies as far as minimum requirements for renewables integration, and state subsidies may contain riders which require a percentage of generated power to stay in-state. More importantly, NIMBY battles may be overshadowed by PIMBY (“Please In My Back Yard”) ones: no state wants to be completely energy-dependent on its neighbors, resulting in significant revenue and jobs being sent over state lines. This creates a barrier to high integration of wind and solar in the most populous regions of the country.

We’re going to see mounting resistance in the construction of the interconnected renewable-powered utopia envisioned by some activists, and it’s going to come at the state level.

Robert Wilson's picture
Robert Wilson on February 16, 2014


Burning wood waste in countries with very high per capita timber production (e.g. Finland) makes sense, and of course already happens. It doesn’t scale up of course. We produce 3 billion cubic metres of wood each year, and for obvious reasons we do not want to produce more.

Heating with electricity is very problematic, mostly because the heating load is very seasonal. As a result electrifying heat will require you to run power plants at significantly lower load factors. And we will probably need a lot of gas power plants to sit idle for a long time for cold winter days with no wind. So, unless gas prices soar it is very difficult to see Europe moving away from heating with gas furnaces.

Bob Meinetz's picture
Bob Meinetz on February 16, 2014

Joe, all of electricity sold to American consumers, whether by Exelon or another utility, is highly regulated both technologically and in price. Little has changed on the front end of the utilty industry, although they’re  now drawing on a diverse range of power sources.

With American power among the most reliable and cheap in the world, what is it exactly you think should be improved about the utility model? What makes you think changing that model won’t result in higher prices and less reliable power?

Bas Gresnigt's picture
Bas Gresnigt on February 17, 2014

Nuclear power has long been known by honest scientists, engiuneers and even some politicians as being absolutely necessary….”

That was in the past century.
By now nuclear is factors more expensive and dangerous than solutions with wind+solar+(pumped)storage.

Now only misguided underdeveloped countries expand nuclear.
Furthermore countries that need nuclear know how to continue their military nuclear capabilities, build some; and few countries that have little wind and/or solar such as Finland.

But even in China electricity production by wind turbines surpassed the production by nuclear last year:




Bas Gresnigt's picture
Bas Gresnigt on February 17, 2014


It would be unwise to do that now as:

  • solar panel yield is ~17% on average now. The best now are ~21.5%. But the yield increases roughly 0.5% each year. So in 15years we have 25% yield average which imply 40% less surface needed.
    Taken into account that the Duthc solar car that won the Australian N-S race, partially had ~40% yield panels, one can consider to wait until 35% (double junction) is the cheap standard.
    That implies only half the surface needed.
  • The best solar panels now have full guarantee period of 25years, that will expand further.
    So we get solar panels that last >100years (as no moving parts).
    That imply little replacement needed.
  • wind turbines also are in their infancy (the present development cycle started in the seventies, just as with solar). So waiting until wind turbines are 20MW (EU study showed that those are feasible) may be useful as a wind park with those turbines grab more power from the wind as they are much higher.
  • These wind turbines also will get longer lifetime, e.g. 60 years, and less maintenance. 
    Especially since the gearbox will vanish, using either high flux permanent magnets or superconducting magnet. The needed cooling unit for superconducting magnets can be rather compact and get a real long life, similar as your fridge.
  • Apart from pumped, storage technology also is in its infancy. Cheap batteries will come. Especially since the electric car and now Germany also create an attractive market (volume).

    Germany started to subsidize batteries (partly grid operator controlled) for households that have rooftop PV, hoping that the mass market will bring prices so much down that those can compete.

Bas Gresnigt's picture
Bas Gresnigt on February 17, 2014

German scenario studies estimate that the extra price to compensate for the variability for wind+solar is insignificant until ~40% renewable.
Until 80% share of renewable in electricity generation, the extra costs are estimated to be ~10% only.

These studies also show why the ~35 small pumped storage facilities in Germany make so much losses that installation of new pumped storage facilities stopped. With the present level of ~24% renewable there is no real need for them yet.
They may become useful (and make profit) in ~2025-2030, when renewable share is ~45-55%.


Bas Gresnigt's picture
Bas Gresnigt on February 17, 2014


With American power among the most reliable and cheap in the world...”
Cheap may be, but reliable for sure not.

Germany (as NL still has) had a total power outage time per customer connection of 30min./year.
With the increased penetration of wind+solar that total outage time decreased towards 15min/year now
(NL is still at 30min/year level, but we hardly have wind+solar).

One of the reasons: a sudden outage of some of the million small distributed generators (wind turbines, rooftop solar) has no real influence, while such outage at a 1GW power plant has big influence.
Furthermore the production of that million generators is accurately predicted by the grid operator (weather forecasting, etc).

France and UK are still at the 60min/year level.
USA is at the 120min/year level, 8 times less reliable than Germany!
While outages due to extreme weather conditions are not counted in USA, and do count in Germany.


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