Can Nuclear Power and Renewable Energy Learn to Get Along?

Here’s my contention then: If you want an ultra-low carbon renewable energy system, you need storage and flexibility. And if you have storage and flexibility, then renewables play just fine with nuclear.

That’s Jesse Jenkins’ wrapping up a provocative essay at Energy Collective. I disagree with the implication that ultra-low carbon energy systems must have huge amounts of classical storage and flexibility. Yes, if the system design followed the German Energiewende concept. No, if the system is designed to achieve the optimal nuclear-VRE contributions by exploiting productive variable demand or load-shedding to substitute for most of the storage and flexibility. The variable demand would be products with high value in the region of generation – e.g., syn-fuels, desalinated water, ammonia fertilizers, etc. Nathan Wilson explains the concept of using syn-fuels are the variable demand in the comments:

Should we over-build electrical generation and add fuel synthesis? It depends a lot on whether we need the liquid fuel for other purposes. There will always be some nations that can’t grow enough bio-fuel for their transportation system (maybe most nations). For these nations to get off fossil fuel, their syn-fuel industries will be roughly 1-2 times the size of their electricity industry.

Such a nation would need very little energy storage, since the syn-fuel plants would constitute enough dispatchable load. To put down some ball-park numbers, say the baseload power plant costs $6/Watt (plus fuel for nuclear at around 2¢/kWh) and the hydrogen plant costs an extra $1/Watt, including several days of storage. Then baseload electricity is around 8¢/kWh, and dispatch load at the syn-fuel plants adds 1¢/kWh to the cost of baseload for the idled equipment; this is really cheap peaking power (it does assume that as with today’s costs, per-Watt the chem plant is much cheaper than the nuke, and of course a cheap chem plant is crucial for applicability to low capacity factor off-peak wind and solar).

Thermal energy storage at nuclear plants or advanced batteries (for a few hours) might also fall to the $1/Watt point, but we would still have to pay depreciation for the storage, even on days we didn’t need it. When we don’t need the syn-fuel plant to load-shed, it makes product for its fuel customer, so it does not burden the electricity economics (in reality there would likely be a small payment).

I mentioned several days of hydrogen storage, but note that if liquid fuels (e.g. ammonia or DME) are produced, or if the local geology is suited to underground hydrogen storage, then seasonal energy storage is feasible.

Providing syn-fuel for the entire transportation market using plants configured for dispatchable load is such a powerful tool, that nuclear and renewables can almost be mixed freely on such a grid.

Note that the energy prices given (8¢/kWh for baseload electricity, $1/Watt for hydrogen plant) and 70% conversion efficiency suggest a hydrogen cost of $4.60 per gallon of gasoline equivalent. Conversion to ammonia fuel would add another 5-25%, depending on the technology (this improves storability/transportability and allows simpler ICE cars rather than expensive fuel cell vehicles).

This cost would not be attractive in the US unless the hydrogen/ammonia car got much better mileage than gasoline cars (20-50% better is likely). However, it is possible that the very high temperature nuclear plants in development coupled with thermo-chemical hydrogen production could reduce the cost substantially. Also in China and India nuclear power is only one third of what it costs in the US, so the retail price of ammonia syn-fuel would easily beat imported fuel.

I recommend going directly to the Jesse Jenkins essay Can Nuclear Power and Renewable Energy Learn to Get Along? which is generating a lot of well-informed discussion.

Update: later in the comments Nathan Wilson summarizes the specific case for ammonia instead of synthetic hydrocarbons.

Yes, fuel synthesis is a great way to utilize otherwise-curtailed sustainable energy.  But instead of making methane or other hydrocarbons we should make carbon-free ammonia (NH3), to get several benefits:

  • Capturing the needed nitrogen (which is 80% of air) is much cheaper than trying to capture CO2 from the air, sea, or biomass.
  • Like diesel fuel, ammonia can be burned in high compression internal combustion engines (ICEs), which deliver higher energy efficiency than is possible with gasoline engines; ammonia burns cleaner than diesel, with zero-particulate emissions guaranteed.
  • When leaked, ammonia is not a green-house gas (unlike methane), but it is a buoyant gas (unlike methanol and MTBE which can find their way into waterways).
  • Ammonia use would not create another dependence on continued fossil fuel use to assure CO2 availability.
  • Unlike hydrocarbons, ammonia does not release CO2 when burned, so ammonia (which is made today from fossil fuels for a price competitive with gasoline) can be used to allow fossil fuel with CC&S to join sustainable energy in providing non-CO2-emitting energy for transportation, construction, combined heat & power, or electrical peaking applications (so even countries and regions with deeply entrenched fossil fuel industries can achieve deep reductions in CO2 emissions).
  • Ammonia can be economically stored in large above ground (refrigerated) tanks for seasonal energy storage (applicable to all locations, unlike underground methane storage which requires special geology). 

see also:  http://nh3fuelassociation.org/ 

Update: Jesse Jenkins inserted a comment that nicely illustrates the arithmetic of the curtailment impact on VRE of more or less nuclear contribution:

Hi Alan,

I grant that without lots of economic storage/sinks, you’d hit the cieling on renewables faster if you have a share of nuclear in the system as well. So if your goal is to increase renewables to their highest penetration before hitting their cieling before needing storage, then you’d want to back off of nuclear. But if your goal is to get to the lowest carbon power system as possible before needing storage, then I doubt that’s the best way to go.

Simple math here but I think this gets at the gist of it: if your system is say 20% nuclear, then you’d hit the renewables cieling roughly when their energy share = their capacity factor x (100% – nuclear’s share). So for solar at 10% CF, you’d hit the cieling at 10% x (100% – 20%) = about 8% of the energy mix from solar instead of 10% if you had no nuclear in the system. For wind at 33% CF, you’d hit the cieling at 33% x (100% – 20%) = about 26% of the energy mix from wind instead of about 33% if you had no nuclear in the system.

So yes, you lose a few percentage points of renewables share if you have 20% nuclear in your system versus if you don’t. But if carbon is your priority, it makes no sense to give up that 20% from zero-carbon nuclear in order to get 2% more solar or 7% more wind!

So again: if you want an ultra low-carbon energy system with high penetrations of solar or wind, you need massive amounts of economic storage and sinks and DR. And if you have those, nuclear and renewables seem to work just fine together. And if nuclear and renewables aren’t mutally exclusive, the lowest CO2 for the least money may very well be a hybrid system.

Jesse

 

The Nexus of Biofuels, Climate Change, and Human Health

For bioenergy to reduce greenhouse gas emissions through plant growth, it must lead to additional plant growth.

NewImageI have been seeking authoritative but accessible sources on whether the current fashion for biofuel subsidies and mandates is a good idea or a bad idea. Questions: are biofuels…

  • Mitigating GHG emissions for transportation fuels?
  • Raising food prices for the poor?
  • Threatening global forest cover?
  • Negatively impacting soil quality?
  • Negatively impacting fresh water supplies?
  • What if cellulosic biofuels can be made to work at scale?

To cut to the chase, I have concluded that encouraging biofuel production may be good for farmers but biofuels are bad for humanity and bad for the planet. While there are some exceptions, my main concern is the broad sweep of public policy, which I find in the rich world to be going in the wrong direction. If you are also wishing to know the scorecard for biofuels I have some sources to recommend. First is the captioned January 2013 workshop organized by the USA National Academy of Sciences. This workshop was convened specifically to investigate the current state of knowledge on biofuels. The workshop proceedings are available at The National Academies Press: The Nexus of Biofuels, Climate Change, and Human Health where you can purchase the paperback for $35, download the free PDF or read online. The Workshop video is all available on YouTube in 48 segments.

There is a heap of depth in the proceedings so you will be rewarded if you can invest a few hours digesting. For motivation here are a few excerpts from the beginning of first presentation — which is by Timothy D. Searchinger (see end note).

Many governments around the world have either goals or mandates for biofuels, Searchinger said, and if these goals and mandates are met, biofuels will account for about 10 percent of the world’s transportation fuels by 2020. This represents about 2.5 percent of the world’s total energy budget, but Searchinger said, when the energy that it takes to make biofuels is taken into account, biofuels would be providing about 1.7 percent of the world’s delivered energy by 2020.
How much of the world’s crops would that take? By 2020 biofuels would require that about 26 percent of all the energy contained in the present production of the world’s crops. By 2050 that figure would rise to 36 percent, he added. “So, that gives you some idea of the challenge, which is that it takes a large amount of biomass to get a small amount of energy.”

Of course, liquid biofuels are only one form of bioenergy that people are interested in, he noted. For example, there is also a big push in Europe as well as in some U.S. states to produce electricity from wood products.

Governments are encouraging the use of bioenergy in various ways. The European Commission has required, for instance, that 20 percent of all energy in Europe be renewable by 2020—not just the energy from utilities, but all energy. It is expected now that more than half of that will come from bioenergy, Searchinger said. A number of states have renewable energy targets, he said, although they are not quite as stringent and are just for electricity.

The Effect of Biofuels Usage on Carbon Dioxide Levels

One of the main reasons that people support the use of biofuels, Searchinger said, is the belief that “when you switch from burning a fossil fuel to burning a biofuel you get some kind of direct greenhouse gas benefit.” But, he said, a close examination indicates that this is not the case and that the belief that there is a direct benefit stems from an “accounting error.”

The belief that burning biofuels contributes less carbon dioxide to the atmosphere than burning fossil fuels stems from the fact that biofuels are derived from plants, which absorb carbon dioxide as they grow. “So, the theory is that, in effect, bioenergy is just recycling carbon, not emitting new carbon.” That is wrong, however, for the simple reason that land typically supports plant growth, whether it is used for bioenergy or not. For bioenergy to reduce greenhouse gas emissions through plant growth, it must lead to additional plant growth.

(…snip…) The key concept here, Searchinger said, is that the benefit from ethanol depends on the existence of an offset that makes up for the fact that producing and burning ethanol actually creates much more green- house gases than producing and burning gasoline. So, the question is: Is there really such an offset? It is true that growing corn leads to a certain amount of carbon dioxide being pulled from the atmosphere, but that is not all that goes into the determination of the offset. The critical requirement for an “offset” is that it be additional. No one can take credit for a carbon sink, such as a tree if that tree already exists anyway—in this case, regardless of whether the biofuels exist or not. One must take into account all of the circumstances surrounding the production of the ethanol and compare what happens when corn is being grown to produce ethanol to what happens when corn is not being grown to produce ethanol.

The first thing that must be considered is the land that is used to grow plants. “Land grows plants whether it’s growing those plants for biofuels or not,” Searchinger pointed out. “So, those plants are already up taking carbon if you’re growing it for biofuels or not.” Thus, the only way that there is a legitimate offset from growing corn for ethanol is if more plants are being grown on that same amount of land or, specifically, if more carbon dioxide is taken up by the corn crop than was taken up by whatever was growing on that land before the corn. “One way to think about it is that if you had a bare piece of land and you allowed it to grow as a forest, that forest would accumulate carbon, and it would reduce greenhouse gas emissions. On the other hand, if you simply had a forest that was growing anyway, you couldn’t count that as an offset.”

Ignoring this basic fact is a fundamental error that often appears in calculating the biofuels offset. “Biofuel analysis assumes typically that all plant growth offsets biofuels, rather than only additional plant growth,” Searchinger said.

(…snip…) The most effective approach would be producing cellulosic ethanol—ethanol produced from wood or grasses—on the land, but even in that case, Searchinger said, “you’re simply matching the opportunity cost of using that land for another purpose.” And if the cropland is created by clearing forest, there is a much greater cost in greenhouse gases because plowing up forests will release 12 to 35 tons of carbon dioxide per hectare each year for 30 years. Thus, the best-case biofuels scenario would be to take fallow land and use it for the production of cellulosic ethanol, he said, but even in that case it is only a break-even situation if the land would otherwise come from abandoned land, and it would increase emissions if the land used was previously forest. There is no offset.

In short, out of the three possible indirect effects of growing corn to produce ethanol, Searchinger said, two are bad. (…snip…)

Biofuels and Food Consumption

Interestingly, although reduced food consumption would not appear to be a desirable result, it is exactly what is assumed in the major models used to predict the greenhouse gas effects of biofuels, Searchinger said. “You have to find this deeply in the data,” he said. “It’s generally not reported. Take, for example, the Environmental Protection Agency [EPA] analysis of corn ethanol, which found relatively little land-use change compared to some other studies. One reason it didn’t find as much land-use change as other studies is that it actually estimated that a quarter of all the calories that are diverted to ethanol aren’t replaced.”

Similarly, the model used by the California Air Resources Board assumed that more than half of the calories from the corn diverted from human and animal consumption to ethanol would not be replaced. A major model used by the European Union assumes that a quarter of the calories from either corn ethanol or wheat ethanol are not replaced.

Thus, the greenhouse gases benefit from using biofuels, as calculated by these models, depends on humans and animals eating less, expending less energy, and thus breathing out less carbon dioxide (and producing less methane). “If you were to eliminate these savings,” he said, “you would not have greenhouse gas savings according to all these models.”

Of course, he noted, the decreased consumption assumed by these models is not a desirable effect because there remains a great deal of hunger in the world—roughly 900 million people are hungry according to recent estimates. Thus, it is particularly worrisome that the frequency of food crises worldwide has essentially tripled since 2005, when the amount of biofuels use began to increase sharply. And according to a recent report by the High-Level Panel on Food Security, of which Searchinger is a member, that is not a coincidence (HLPE, 2013). “We basically conclude that biofuels are the dominant source of food price increases.”

In particular, the increase in corn prices in the United States can be traced to the cost of oil combined with government tax credits for ethanol production. With crude oil at $80 per barrel and with the current U.S. tax credits for ethanol, it is economical to use corn to make ethanol and to replace gasoline until the price of corn reaches about $6.80 per bushel. “Roughly speaking,” he said, “this is a 275 percent higher price than the long-term corn price in the first part of the 2000s.” Thus, corn prices get bid up until they get close to that level—and as the price for corn intended for ethanol production increases, the price for corn intended for consumption increases along with it, for the crops are the same. Furthermore, as the price of corn increases, the price of wheat and soybeans—and, to a lesser extent, rice—track the price of corn very closely because the crops can, to a significant extent, be substituted for one another. “So, this force by itself is perfectly adequate to explain the vast majority of the price rise that we’ve had,” Searchinger said.

(…snip…)

To produce all the crops needed by 2020 for both food and biofuels without any change in land use will require a doubling of the historical yield growth rate, Searchinger said, “and that’s not going to happen.”

What would be the impact of actually achieving EU 2050 goals for biomass and biofuels? The 80% renewables goal is 12% of Total Primary Energy would be biomass. Yikes, what a disaster that would be!

The real challenge with bioenergy, Searchinger said, is that photosynthesis is extremely inefficient. “If you’re really lucky you get half a percent of the solar energy transformed into plant biomass—that’s extraordinary achievement over the course of the year. And eventually maybe a tenth or two-tenths of the original solar energy will end up actually in delivered energy like electricity.” By contrast, a solar cell turns 10 percent of solar energy into electricity. “So, compare one-tenth of 1 percent with 10 percent, and you’ll get an idea of the inefficiency of using land. What that means is it takes a tremendous amount of land to make a small amount of bioenergy.”

The bottom line is that to provide 10 percent of the world’s transportation fuel by 2050 would require 36 percent of all of today’s crop production, and it would amount to less than 2 percent of the world’s delivered energy at that time.

Another way of looking at the inefficiency is that the EROI of biomass is so low (by a factor of two) that it makes a negative contribution to supporting a modern industrial economy. This chart is discussed in The Catch-22 of Energy Storage and EROI — A Tool To Predict The Best Energy Mix:

NewImage

Timothy D. Searchinger, J.D., is a research scholar and lecturer in public and international affairs at Princeton University’s Woodrow Wilson School. He is also a Transatlantic Fellow of the German Marshall Fund of the United States. Timothy D. Searchinger is a Senior Fellow at the World Resources Institute and serves as the technical director of the next World Resources Report.

The Nexus of Biofuels, Climate Change, and Human Health

For bioenergy to reduce greenhouse gas emissions through plant growth, it must lead to additional plant growth.

NewImageI have been seeking authoritative but accessible sources on whether the current fashion for biofuel subsidies and mandates is a good idea or a bad idea. Questions: are biofuels…

  • Mitigating GHG emissions for transportation fuels?
  • Raising food prices for the poor?
  • Threatening global forest cover?
  • Negatively impacting soil quality?
  • Negatively impacting fresh water supplies?
  • What if cellulosic biofuels can be made to work at scale?

To cut to the chase, I have concluded that encouraging biofuel production may be good for farmers but biofuels are bad for humanity and bad for the planet. While there are some exceptions, my main concern is the broad sweep of public policy, which I find in the rich world to be going in the wrong direction. If you are also wishing to know the scorecard for biofuels I have some sources to recommend. First is the captioned January 2013 workshop organized by the USA National Academy of Sciences. This workshop was convened specifically to investigate the current state of knowledge on biofuels. The workshop proceedings are available at The National Academies Press: The Nexus of Biofuels, Climate Change, and Human Health where you can purchase the paperback for $35, download the free PDF or read online. The Workshop video is all available on YouTube in 48 segments.

There is a heap of depth in the proceedings so you will be rewarded if you can invest a few hours digesting. For motivation here are a few excerpts from the beginning of first presentation — which is by Timothy D. Searchinger (see end note).

Many governments around the world have either goals or mandates for biofuels, Searchinger said, and if these goals and mandates are met, biofuels will account for about 10 percent of the world’s transportation fuels by 2020. This represents about 2.5 percent of the world’s total energy budget, but Searchinger said, when the energy that it takes to make biofuels is taken into account, biofuels would be providing about 1.7 percent of the world’s delivered energy by 2020.How much of the world’s crops would that take? By 2020 biofuels would require that about 26 percent of all the energy contained in the present production of the world’s crops. By 2050 that figure would rise to 36 percent, he added. “So, that gives you some idea of the challenge, which is that it takes a large amount of biomass to get a small amount of energy.”

Of course, liquid biofuels are only one form of bioenergy that people are interested in, he noted. For example, there is also a big push in Europe as well as in some U.S. states to produce electricity from wood products.

Governments are encouraging the use of bioenergy in various ways. The European Commission has required, for instance, that 20 percent of all energy in Europe be renewable by 2020—not just the energy from utilities, but all energy. It is expected now that more than half of that will come from bioenergy, Searchinger said. A number of states have renewable energy targets, he said, although they are not quite as stringent and are just for electricity.

The Effect of Biofuels Usage on Carbon Dioxide Levels

One of the main reasons that people support the use of biofuels, Searchinger said, is the belief that “when you switch from burning a fossil fuel to burning a biofuel you get some kind of direct greenhouse gas benefit.” But, he said, a close examination indicates that this is not the case and that the belief that there is a direct benefit stems from an “accounting error.”

The belief that burning biofuels contributes less carbon dioxide to the atmosphere than burning fossil fuels stems from the fact that biofuels are derived from plants, which absorb carbon dioxide as they grow. “So, the theory is that, in effect, bioenergy is just recycling carbon, not emitting new carbon.” That is wrong, however, for the simple reason that land typically supports plant growth, whether it is used for bioenergy or not. For bioenergy to reduce greenhouse gas emissions through plant growth, it must lead to additional plant growth.

(…snip…) The key concept here, Searchinger said, is that the benefit from ethanol depends on the existence of an offset that makes up for the fact that producing and burning ethanol actually creates much more green- house gases than producing and burning gasoline. So, the question is: Is there really such an offset? It is true that growing corn leads to a certain amount of carbon dioxide being pulled from the atmosphere, but that is not all that goes into the determination of the offset. The critical requirement for an “offset” is that it be additional. No one can take credit for a carbon sink, such as a tree if that tree already exists anyway—in this case, regardless of whether the biofuels exist or not. One must take into account all of the circumstances surrounding the production of the ethanol and compare what happens when corn is being grown to produce ethanol to what happens when corn is not being grown to produce ethanol.

The first thing that must be considered is the land that is used to grow plants. “Land grows plants whether it’s growing those plants for biofuels or not,” Searchinger pointed out. “So, those plants are already up taking carbon if you’re growing it for biofuels or not.” Thus, the only way that there is a legitimate offset from growing corn for ethanol is if more plants are being grown on that same amount of land or, specifically, if more carbon dioxide is taken up by the corn crop than was taken up by whatever was growing on that land before the corn. “One way to think about it is that if you had a bare piece of land and you allowed it to grow as a forest, that forest would accumulate carbon, and it would reduce greenhouse gas emissions. On the other hand, if you simply had a forest that was growing anyway, you couldn’t count that as an offset.”

Ignoring this basic fact is a fundamental error that often appears in calculating the biofuels offset. “Biofuel analysis assumes typically that all plant growth offsets biofuels, rather than only additional plant growth,” Searchinger said.

(…snip…) The most effective approach would be producing cellulosic ethanol—ethanol produced from wood or grasses—on the land, but even in that case, Searchinger said, “you’re simply matching the opportunity cost of using that land for another purpose.” And if the cropland is created by clearing forest, there is a much greater cost in greenhouse gases because plowing up forests will release 12 to 35 tons of carbon dioxide per hectare each year for 30 years. Thus, the best-case biofuels scenario would be to take fallow land and use it for the production of cellulosic ethanol, he said, but even in that case it is only a break-even situation if the land would otherwise come from abandoned land, and it would increase emissions if the land used was previously forest. There is no offset.

In short, out of the three possible indirect effects of growing corn to produce ethanol, Searchinger said, two are bad. (…snip…)

Biofuels and Food Consumption

Interestingly, although reduced food consumption would not appear to be a desirable result, it is exactly what is assumed in the major models used to predict the greenhouse gas effects of biofuels, Searchinger said. “You have to find this deeply in the data,” he said. “It’s generally not reported. Take, for example, the Environmental Protection Agency [EPA] analysis of corn ethanol, which found relatively little land-use change compared to some other studies. One reason it didn’t find as much land-use change as other studies is that it actually estimated that a quarter of all the calories that are diverted to ethanol aren’t replaced.”

Similarly, the model used by the California Air Resources Board assumed that more than half of the calories from the corn diverted from human and animal consumption to ethanol would not be replaced. A major model used by the European Union assumes that a quarter of the calories from either corn ethanol or wheat ethanol are not replaced.

Thus, the greenhouse gases benefit from using biofuels, as calculated by these models, depends on humans and animals eating less, expending less energy, and thus breathing out less carbon dioxide (and producing less methane). “If you were to eliminate these savings,” he said, “you would not have greenhouse gas savings according to all these models.”

Of course, he noted, the decreased consumption assumed by these models is not a desirable effect because there remains a great deal of hunger in the world—roughly 900 million people are hungry according to recent estimates. Thus, it is particularly worrisome that the frequency of food crises worldwide has essentially tripled since 2005, when the amount of biofuels use began to increase sharply. And according to a recent report by the High-Level Panel on Food Security, of which Searchinger is a member, that is not a coincidence (HLPE, 2013). “We basically conclude that biofuels are the dominant source of food price increases.”

In particular, the increase in corn prices in the United States can be traced to the cost of oil combined with government tax credits for ethanol production. With crude oil at $80 per barrel and with the current U.S. tax credits for ethanol, it is economical to use corn to make ethanol and to replace gasoline until the price of corn reaches about $6.80 per bushel. “Roughly speaking,” he said, “this is a 275 percent higher price than the long-term corn price in the first part of the 2000s.” Thus, corn prices get bid up until they get close to that level—and as the price for corn intended for ethanol production increases, the price for corn intended for consumption increases along with it, for the crops are the same. Furthermore, as the price of corn increases, the price of wheat and soybeans—and, to a lesser extent, rice—track the price of corn very closely because the crops can, to a significant extent, be substituted for one another. “So, this force by itself is perfectly adequate to explain the vast majority of the price rise that we’ve had,” Searchinger said.

(…snip…)

To produce all the crops needed by 2020 for both food and biofuels without any change in land use will require a doubling of the historical yield growth rate, Searchinger said, “and that’s not going to happen.”

What would be the impact of actually achieving EU 2050 goals for biomass and biofuels? The 80% renewables goal is 12% of Total Primary Energy would be biomass. Yikes, what a disaster that would be!

The real challenge with bioenergy, Searchinger said, is that photosynthesis is extremely inefficient. “If you’re really lucky you get half a percent of the solar energy transformed into plant biomass—that’s extraordinary achievement over the course of the year. And eventually maybe a tenth or two-tenths of the original solar energy will end up actually in delivered energy like electricity.” By contrast, a solar cell turns 10 percent of solar energy into electricity. “So, compare one-tenth of 1 percent with 10 percent, and you’ll get an idea of the inefficiency of using land. What that means is it takes a tremendous amount of land to make a small amount of bioenergy.”

The bottom line is that to provide 10 percent of the world’s transportation fuel by 2050 would require 36 percent of all of today’s crop production, and it would amount to less than 2 percent of the world’s delivered energy at that time.

Another way of looking at the inefficiency is that the EROI of biomass is so low (by a factor of two) that it makes a negative contribution to supporting a modern industrial economy. This chart is discussed in The Catch-22 of Energy Storage and EROI — A Tool To Predict The Best Energy Mix:

NewImage

Timothy D. Searchinger, J.D., is a research scholar and lecturer in public and international affairs at Princeton University’s Woodrow Wilson School. He is also a Transatlantic Fellow of the German Marshall Fund of the United States. Timothy D. Searchinger is a Senior Fellow at the World Resources Institute and serves as the technical director of the next World Resources Report.

 

A closer look at the flawed studies behind policies used to promote ‘low-carbon’ biofuels

Source: University of Michigan press release — which begins with this:

Nearly all of the studies used to promote biofuels as climate-friendly alternatives to petroleum fuels are flawed and need to be redone, according to a University of Michigan researcher who reviewed more than 100 papers published over more than two decades.

Once the erroneous methodology is corrected, the results will likely show that policies used to promote biofuels—such as the U.S. Renewable Fuel Standard and California’s Low-Carbon Fuel Standard—actually make matters worse when it comes to limiting net emissions of climate-warming carbon dioxide gas.

The main problem with existing studies is that they fail to correctly account for the carbon dioxide absorbed from the atmosphere when corn, soybeans and sugarcane are grown to make biofuels, said John DeCicco, a research professor at U-M’s Energy Institute.

“Almost all of the fields used to produce biofuels were already being used to produce crops for food, so there is no significant increase in the amount of carbon dioxide being removed from the atmosphere. Therefore, there’s no climate benefit,” said DeCicco, the author of an advanced review of the topic in the current issue of Wiley Interdisciplinary Reviews: Energy and Environment.

“The real challenge is to develop ways of removing carbon dioxide at faster rates and larger scales than is accomplished by established agricultural and forestry activities. By focusing more on increasing net carbon dioxide uptake, we can shape more effective climate policies that counterbalance emissions from the combustion of gasoline and other liquid fuels.”

The DeCicco paper The liquid carbon challenge: evolving views on transportation fuels and climate is a valuable resource on biofuels. The paper is blessedly OPEN ACCESS. 

WIREs Energy Environ 2015, 4:98–114. doi: 10.1002/wene.133

I recommend a careful read of DeCicco. For a one-graphic-summary I chose Figure 4 which shows that biofuels are not significant contributors to decarbonization if indirect land-use change (ILUC) is “correctly” accounted.

NewImage

EROI — A Tool To Predict The Best Energy Mix

I’m happy to see that Forbes contributor James Conca has taken on the central EROI issue — what John Morgan termed the The Catch-22 of Energy Storage. In today’s essay EROI — A Tool To Predict The Best Energy Mix Jim engages directly with the reality that affordable utility-scale storage does NOT make solar PV and biomass into big winners in the future low-carbon energy portfolio. Jim contributed an effective new chart that combines both the with-storage and without-storage EROI profiles. The dotted line at EROI = 7 represents an estimate of the minimum performance required to support a modern industrial society, as represented by the OECD countries.

NewImage

Both John Morgan and Jim Conca based their analysis on the important 2013 paper by Weißbach et al (ungated preprint) published in Energy, Volume 52, 1 April 2013, Pages 210–221.

I want to emphasize that not only is this paper a major conceptual contribution to the energy policy, it is also a model of transparency. Included in the supplementals of the Weißbach et al. paper – are the spreadsheets containing all the materials reference data, assumptions and the EROI and EMROI computations. This means that any motivated reader can audit every detail of the energy inputs, material requirements and computations.

If any reader objects to any of the assumptions they are free to amend the Weisbach spreadsheets to compute their own preferred EROI profiles.

An excellent example of the transparency benefit of the Weisbach spreadsheet contribution is Keith Pickering’s GETTING TO ZERO: Is renewable energy economically viable? Keith used the Weißach model to analyze the progressively improving EROI of nuclear fission. 

With 100% centrifuge, nuclear will have an EROI of 106, EMROI of 166 according to Weißbach’s analysis.

Here’s an earlier 8/13/14 Seekerblog post on the Morgan and Weißach work.

Can you build a wind turbine without fossil fuels?

Wind

Robert Wilson addressed the captioned question in Wind Turbines and Fuel Used in Creation. Robert summarized the materials required for wind nameplate generation capacity:

On average 1 MW of wind capacity requires 103 tonnes of stainless steel, 402 tonnes of concrete, 6.8 tonnes of fiberglass, 3 tonnes of copper and 20 tonnes of cast iron. The elegant blades are made of fiberglass, the skyscraper sized tower of steel, and the base of concrete.

I think of the captioned question from a slightly different angle:

If we have a grid powered only by wind power — will we be able to replace the aging turbines at their 20 to 25 year end-of-life?

I think the answer to my question is

  1. We must synthesize a substitute for the diesel fuel.
  2. We will still need coal and/or natural gas for steelmaking and cement.
  3. Regardless of chemistry we will need a LOT of reliable, clean energy to manufacture the replacement wind turbines every 25 years or so.

To synthesize all those fuels you will want to have plenty of low-carbon nuclear electricity. And the chemistry of both steel and concrete production will continue to produce large volumes of CO2 (absent innovations I’m not aware of).

Robert walks the reader through the steel supply chain from ore mining and transport, to the blast furnace that converts the iron ore into steel. Every step requires (steel) heavy machinery and copious fossil fuel to power the engines. The final stages require either or both coal (coke for the iron ore to iron reduction) and natural gas. From Chemistry Explained:

Steel furnaces. In the steel furnace, sulfur and phosphorus impurities and excess carbon are burned away, and manganese and other alloying ingredients are added. During the nineteenth century most steel was made by the Bessemer process, using big pear-shaped converters. During the first half of the twentieth century, the open hearth furnace became the main type of steel furnace. This gave way mid-century to the basic oxygen process, which used pure oxygen instead of air, cutting the process time from all day to just a few hours. In the twenty-first century, most new steel plants use electric furnaces, the most popular being the electric-arc furnace. It is cheaper to build and more efficient to operate than the basic oxygen furnace. In the electric-arc furnace a powerful electric current jumps (or arcs) between the electrodes, generating intense heat, which melts the iron scrap that is typically fed into it.

The most modern process for making steel is the continuous process, which bypasses the energy requirements of the blast furnace. Instead of using coke, the iron ore is reduced by hydrogen and CO derived from natural gas. This direct reduction method is especially being used in developing countries where there are not any large steel plants already in operation. 

The 402 tons of concrete per MW of nameplate capacity requires the similarly challenging cement supply chain (from US EIA)

NewImage(…snip…) the most energy-intensive of all manufacturing industries, with a share of national energy use roughly 10 times its share of the nation’s gross output of goods and services. (…snip…) Cement is also unique in its heavy reliance on coal and petroleum coke.

 

 And because wind capacity factors are typically 25 to 35% in excellent productivity areas, and because we are assuming that the electric grid depends entirely on 100% wind power, then we will have to build 3 to 4 times as many wind turbines as the nameplate capacity promises. That’s a lot of concrete and a lot of steel. Back to Robert Wilson, who concludes with this:

Total cement production currently represents about 5% of global carbon dioxide emissions, to go with the almost 7% from iron and steel production. Not loose change.

In conclusion we obviously cannot build wind turbines on a large scale without fossil fuels.

Now, none of this is to argue against wind turbines, it is simply arguing against over-promising what can be achieved. It also should be pointed out that we cannot build a nuclear power plant, or any piece of large infrastrtucture for that matter, without concrete or steel. A future entirely without fossil fuels may be desirable, but currently it is not achievable. Expectations must be set accordingly.

 

The Great Progressive Reversal: how the TVA supporters became the prison jailers of the developing poor

It wasn’t long before environmental groups came to oppose nearly all forms of grid electricity in poor countries, whether from dams, coal or nuclear.

“Giving society cheap, abundant energy, would be the equivalent of giving an idiot child a machine gun.” —Paul Ehrlich 1975

Prof. Erlich continues to preach the same theme, which is essentially the low energy hymnal as written by Amory Lovins. I think Erlich and Lovins are completely on the wrong side of the low-energy/high-energy debate. If you are an Amory Lovins believer I hope to persuade you to read The Breakthrough Institute’s concise briefing document Our High-Energy Planet. Arizona State University's Dan Sarewitz is one of my trusted sources on science policy issues. Here’s Dan’s summary of the choice between high-energy and low-energy policies:

“Climate change can’t be solved on the backs of the world’s poorest people,” said Daniel Sarewitz, coauthor and director of ASU’s Consortium for Science, Policy, and Outcomes. “The key to solving for both climate and poverty is helping nations build innovative energy systems that can deliver cheap, clean, and reliable power.”

If, after reading Our High Energy Planet, you are still thinking that we already have all the tech required, that all we need to address climate change is more efficiency and renewables, then I recommend that you need to learn more about the staggering magnitude of the energy transition required. Start with energy expert Vaclav Smil’s Power Density Primer, then his Energy Transitions and finally Will nine billion people exhaust our materials resources?

If, like me, you are puzzling over how the former protectors of the energy-impoverished have transformed into the prison guards responsible for preventing their escape, their breakout from the energy-poverty jail — then read the captioned three-part The Great Progressive Reversal. This is a very different history than what I was taught in public schools, even university. When I studied civics and social history the prevailing progressive theme was the signature New Deal program of the TVA, the Tennessee Valley Authority.

(…snip…) In 1933 Congress and President Roosevelt authorized the creation of the Tennessee Valley Authority. It mobilized thousands of unemployed men to build hydroelectric dams, produce fertilizer, and lay down irrigation systems. Sensitive to local knowledge, government workers acted as community organizers, empowering local farmers to lead the efforts to improve agricultural techniques and plant trees.

The TVA produced cheap energy and restored the natural environment. Electricity from the dams allowed poor residents to stop burning wood for fuel. It facilitated the cheap production of fertilizer and powered the water pumps for irrigation, allowing farmers to grow more food on less land. These changes lifted incomes and allowed forests to grow back. Although dams displaced thousands of people, they provided electricity for millions.

By the 50s, the TVA was the crown jewel of the New Deal and one of the greatest triumphs of centralized planning in the West. It was viewed around the world as a model for how governments could use modern energy, infrastructure and agricultural assistance to lift up small farmers, grow the economy, and save the environment. Recent research suggests that the TVA accelerated economic development in the region much more than in surrounding and similar regions and proved a boon to the national economy as well.

Perhaps most important, the TVA established the progressive principle that cheap energy for all was a public good, not a private enterprise. When an effort was made in the mid-'50s to privatize part of the TVA, it was beaten back by Senator Al Gore Sr. The TVA implicitly established modern energy as a fundamental human right that should not be denied out of deference to private property and free markets.

From The Great Progressive Reversal I learned how the progressive movement mutated into what it is today, a supporter of anti-progress development policies. The three-part series concludes with this:

Since Ehrlich made his famous prediction, the global death rate declined from 13 to 9 deaths per 1,000 lives, and India’s fertility rate declined from 5.5 to 2.5, thanks not to forced sterilization's and cutting off food aid, as Ehrlich advocated, but due to the continuing development and modernization of Indian society.

If there is to be a solution to global warming, then it is as likely to come from the rising powers of the global East and South than the superannuated precincts of the West. “Old men like to offer good advice,” Bruckner writes, quoting the 18th-century philosopher François de la Rouchefoucauld, “in order to console themselves for no longer being in a position to give bad examples.”

 

 

System LCOE and minimizing GHG avoidance costs

Recent references on full life cycle costing of electricity generation options – including accounting for intermittency and integration costs.

Why the Best Path to a Low-Carbon Future is Not Wind or Solar Power Analysis of Brookings paper by Charles Frank

This paper examines five different low and no-carbon electricity technologies and presents the net benefits of each under a range of assumptions. It estimates the costs per megawatt per year for wind, solar, hydroelectric, nuclear, and gas combined cycle electricity plants. To calculate these estimates, the paper uses a methodology based on avoided emissions and avoided costs, rather than comparing the more prevalent “levelized” costs. Three key findings result:

First—assuming reductions in carbon emissions are valued at $50 per metric ton and the price of natural gas is $16 per million Btu or less—nuclear, hydro, and natural gas combined cycle have far more net benefits than either wind or solar. This is the case because solar and wind facilities suffer from a very high capacity cost per megawatt, very low capacity factors and low reliability, which result in low avoided emissions and low avoided energy cost per dollar invested.

Second, low and no-carbon energy projects are most effective in avoiding emissions if a price for carbon is levied on fossil fuel energy suppliers. In the absence of an appropriate price for carbon, new no-carbon plants will tend to displace low-carbon gas combined cycle plants rather than high-carbon coal plants and achieve only a fraction of the potential reduction in carbon emissions. The price of carbon should be high enough to make production from gas-fired plants preferable to production from coal-fired plants, both in the short term, based on relative short-term energy costs, and the longer term, based on relative energy and capacity costs combined.

Third, direct regulation of carbon dioxide emissions of new and existing coal-fired plants, as proposed by the U.S. Environmental Protection Agency, can have some of the same effects as a carbon price in reducing coal plant emissions both in the short term and in the longer term as old, inefficient coal plants are retired. However, a price levied on carbon dioxide emissions is likely to be a less costly way to achieve a reduction in carbon dioxide emissions.

The Optimal Share of Variable Renewables. How the Variability of Wind and Solar Power Affects Their Welfare-Optimal Deployment

This paper estimates the welfare-optimal market share of wind and solar power, explicitly taking into account their output variability. We present a theoretical valuation framework that consistently accounts for output variability over time, forecast errors, and the location of generators in the power grid, and evaluate the impact of these three factors on the marginal value of electricity from renewables. Then we estimate the optimal share of wind and solar power in Northwestern Europe from a calibrated numerical power market model. The optimal long-term share of wind power of total electricity consumption is estimated to be 20% at cost levels of 50 €/MWh, about three times the current market share of wind; but this estimate is subject to significant parameter uncertainty. Variability significantly impacts results: if winds were constant, the optimal share would be 60%. In addition, the effect of technological change, price shocks, and policies on the optimal share is assessed. We present and explain several surprising findings, including a negative impact of CO2 prices on optimal wind deployment.

 System LCOE/ What are the Costs of Variable Renewables? by Falko Ueckerdt, Lion Hirth, Gunnar Ludere

Levelized costs of electricity (LCOE) are a common metric for comparing power generating technologies. However, there is qualified criticism particularly towards evaluating variable renewables like wind and solar power based on LCOE because it ignores integration costs that occur at the system level. In this paper we propose a new measure System LCOE as the sum of generation and integration costs per unit of VRE. For this purpose we develop a conclusive definition of integration costs. Furthermore we decompose integration costs into different cost components and draw conclusions for integration options like transmission grids and energy storage. System LCOE are quantified from a power system model and a literature review. We find that at moderate wind shares (~20%) integration costs can be in the same range as generation costs of wind power and conventional plants. Integration costs further increase with growing wind shares. We conclude that integration costs can become an economic barrier to deploying VRE at high shares. This implies that an economic evaluation of VRE must not neglect integration costs. A pure LCOE comparison would significantly underestimate the costs of VRE at high shares. System LCOE give a framework of how to consistently account for integration costs and thus guide policy makers and system planers in designing a cost-efficient power system.

Wade Allison: Why radiation is much safer than you think

Originally man relied for energy on the digestion of food like all animals, but at a historic moment he began to domesticate fire as a source of external energy for lighting, cooking and heating his home. Although this was a dangerous step, it was essential to civilisation. No doubt the environmentalists of those days objected and had a strong case, but they had to accept that the benefits outweighed the dangers, provided education and training in the use of fire was given to everybody including children.

Recently retired Oxford physicist Wade Allison continues helping people understand that radiation risks are radically less than the usual media alarmism. Prof. Allison used this cartoon in his recent video interview, to illustrate the political situation when humans first began to burn fuel outside of their bodies.

Here’s a sample of his science communications:

Nuclear Has Scaled Far More Rapidly Than Renewables – The Clean Energy Transition Needs the Atom


Anyone interested in rapidly increasing the production of clean energy should look to nuclear. The most ambitious renewables plan — Germany’s Energiewende — has brought far less zero-carbon energy far less quickly than similar efforts focused on nuclear. Being cool, profitable and popular is fine, but irrelevant. We need a reliable technology that delivers deep energy emission cuts and we need it fast. — Geoff Russell

Please bookmark Geoff Russell’s essay on The Breakthrough. In a very few words Geoff makes it completely clear that nuclear is an essential part of any sane strategy for slashing carbon emissions.  The anti-nuclear activists are the problem.

How do the rollout speeds of renewables and nuclear power compare?

Let’s compare the speed of per capita electricity generation growth in a few countries for renewables and nuclear. I’m guessing nobody will object if we use the German wunderkind as a top performing renewables example. We’ll plot the last 11 years of wind and solar growth, starting 12 months after the beginning of their feed-in-tariff scheme. We’ll also throw in the last 11 years of Chinese per capita electricity growth from all sources. This is just to put their coal/wind/nuclear/solar/hydro build in proper per capita context.

All of our comparison cases, except one, are historical. They aren’t plans, they are achievements. Anti-nuclear campaigners are fond of finding particular nuclear power stations with time or cost overruns to ‘prove’ how slow or expensive nuclear electricity is to roll out. Cherry picking examples is a time-honored strategy when objective argument fails.

(…snip…)

Being cool, profitable, and popular is fine, but irrelevant. We need a reliable technology that delivers deep energy emission cuts and we need it fast.

It’s rapidly becoming crystal clear that the biggest enemy we face in preventing ongoing climate destabilistation is the anti-nuclear movement. They have cost the planet two decades which could otherwise have seen many more countries with clean electricity, and now they are running a distracting strategy promoting technologies which are intrinsically slow to roll out. They have, in effect, created an energy growth vacuum being filled by coal seam gas which is quick to build but which won’t prevent further climate destabilisation.