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New paper shows that renewables can supply 100% of all energy (not just electricity)

Posted on 20 August 2015 by michael sweet

A new paper: 100% clean and renewable wind, water, and sunlight (WWS) all-sector energy roadmaps for the 50 United States by Jacobson et al 2015 describes the wind, solar and other renewable technologies needed to supply all the energy used in the USA That is all the energy, not just the electricity. They find that using wind to generate 50% of energy, solar photovoltaic (PV) for 38%, concentrated solar power (CSP) for 13% and a combination of hydro, geothermal, tide and wave power for the remainder (5%) allows all energy in the USA to be supplied at a lower cost than using fossil fuels. (The total is over 100% as extra power is required to stabilize the power grid because the wind does not always blow and the sun does not always shine).

figure 5 from Jacobson et al

Fig. 5 (from Jacobson et al 2015) Time-dependent change in U.S. end-use power demand for all purposes (electricity, transportation, heating/cooling, and industry) and its supply by conventional fuels and WWS generators based on the state roadmaps proposed here. Total power demand decreases upon conversion to WWS due to the efficiency of electricity over combustion and end-use energy efficiency measures. The percentages on the horizontal date axis are the percent conversion to WWS that has occurred by that year. The percentages next to each WWS source are the final estimated penetration of the source. The 100% demarcation in 2050 indicates that 100% of all-purpose power is provided by WWS technologies by 2050, and the power demand by that time has decreased. 

The jobs required to build and run the renewable power supply would be greater than the jobs lost by closing down the fossil and nuclear power suppliers. About 0.42% of land would be covered by the generators. An additional 1.6 % of land would have wind generators spaced widely. The land in between could be used for farming or other uses.

This paper quantitates the work required to bring carbon emissions down to zero and shows that it can be done in a cost effective manner. There are few technical barriers that need to be overcome to implement this proposal. The primary issue is lack of political will.

For this paper Jacobson et al set up enough renewable generators in each of the 50 states to generate all the power needed for that state. A separate grid integration study (just accepted for publication in the Proceedings of the National Academy of Science pending minor revisions) details the grid interconnections needed to provide 24/7 power coverage for all the states. Since renewable energy varies over the USA, a stronger grid is required to ensure everyone has enough power all the time.

Jacobson et al. have previously developed roadmaps for California  and New York  This paper expands on that previous work and shows that all 50 states can generate the power they require. Jacobson et al have developed similar roadmaps for many countries and for the globe as a whole.

They followed this procedure:

“The methods used here to create each state roadmap are broadly similar to those recently developed for New York, California, and the world as a whole. Such methods are applied here to make detailed, original, state-by-state estimates of

(1) Future energy demand (load) in the electricity, transportation, heating/cooling, and industrial sectors in both a business-as-usual (BAU) case and a WWS case;

(2) The numbers of WWS generators needed to meet the estimated load in each sector in the WWS case;

(3) Footprint and spacing areas needed for WWS generators;

(4) Rooftop areas and solar photovoltaic (PV) installation potentials over residential and commercial/government buildings and associated carports, garages, parking lots, and parking structures;

(5) The levelized cost of energy today and in 2050 in the BAU and WWS cases;

(6) Reductions in air-pollution mortality and associated health costs today based on pollution data from all monitoring stations in each state and in 2050, accounting for future reductions in emissions in the BAU versus WWS cases;

(7) Avoided global-warming costs today and in 2050 in the BAU versus WWS cases; and

(8) Numbers of jobs produced and lost and the resulting revenue changes between the BAU and WWS cases”

In a previous study (with 593 citations!) Jacobson identified the WWS methods that were most cost effective. Nuclear, coal with carbon capture and biofuels were found to not be as effective as the methods evaluated in this paper for various reasons.

field of wind generators

Wind generators would produce about 50% of power in the USA according to Jacobson's proposal.

Jacobson et al describe how industrial processes will be electrified. For example iron can be produced using electric arc furnaces instead of current coal powered blast furnaces. Some technologies need to be developed, for example they project using cryogenic hydrogen to power airplanes and hydrogen fuel cells and electricity to power ships. This raises demand for electricity but removes all fossil fuel use. All states use much less overall power because electricity is more efficient than internal combustion engines and boilers (for example the boilers in coal and nuclear plants are only 33-40% efficient, cars about 25%).

They calculate the number of generators required by each state. For example, Florida has little hydro power resources but good solar while Washington has large hydropower and good wind. They estimate how many solar panels can be installed on top of buildings. Other land uses are calculated based on the WWS resource used. They compare the amount of land required to generate the power with the available land resources and find that the USA has large excess capacity for wind and solar power. Hydro power, which is the most flexible WWS power, is more limited. Tidal, wave and other resources are very small.  They discuss the potential of each of the types of WWS power.  Click here for an interactive map of the power sources for the 50 states.

Many of the costs for fossil fuels are currently borne by taxpayers. In addition to production subsidies, fossil fuels cause billions of dollars yearly in health costs and damages from their pollution. The climate costs are already measurable and will increase in the future. Acid rain, mercury and arsenic pollution are costs the public bears. These costs are estimated and counted as part of the final cost of energy.

A section of the paper estimates how many jobs will be required to install and maintain the WWS resources. This is compared to the current jobs in the fossil fuel and nuclear industry. They find that many more jobs will be created by WWS energy than lost from the fossil fuel industry.

They suggest that if we got serious about avoiding damage from climate change we could eliminate 80% of carbon dioxide emissions by 2030 and 100% by 2050. That would require substantial effort, but compared to the effort in manufacturing military hardware in WW2 it is a doable task. Reducing energy use by more sensible building codes and more efficient use of energy is discussed. Obviously it is easier to make all energy needed if less energy is required.

They discuss the priority of electrifying different industries. Electric cars will be easier to manufacture (since they are already in production) while hydrogen airplanes will require more work.

This is a conservative estimate of the cost of building of a power system for the USA. If the generators were put in the most efficient places, instead of each state generating its own power, it would be substantially cheaper to build the system. Since Florida currently imports coal to supply much of its electricity, why not import electricity from wind generators in Texas in the future?

The paper ends with this summary:

“Based on the scientific results presented, current barriers to implementing the roadmaps are neither technical nor economic. As such, they must be social and political. Such barriers are due partly to the fact that most people are unaware of what changes are possible and how they will benefit from them and partly to the fact that many with a financial interest in the current energy industry resist change. However, because the benefits of converting (reduced global warming and air pollution; new jobs and stable energy prices) far exceed the costs, converting has little downside. This study elucidates the net benefits and quantifies what is possible thus should reduce social and political barriers to implementing the roadmaps.”

This paper shows that it is possible using technology currently manufactured to generate all required energy for an economy like the USA. Standards of living do not have to be lowered to achieve sustainable energy. There is no technical reason not to pursue WWS energy. Unfortunately, the recent article on SkS about the Koch brothers suggests there will be more political problems than technical issues actually implementing a solution.

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Comments 51 to 91 out of 91:

  1. Stranger...  Around here, we prefer to use the abbreviation "SkS" instead of "SS" for obvious reasons.

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  2. Sorry Rob.  I always tell my wife I'm the king of l faux pas.  And it's embarrising after I said I come here everyday.  

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  3. No problem. Honest mistake.

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  4. PhilippeChantreau @48.

    My appologies. When I posted the link it was fully readable. A 737 was to be filled with a hydrogen fuel tank so this was not a commercially viable machine being built. However the link does demonstrate that Beoing are looking at hydrogen fuel cells which was the contended issue.

    Further, CRYOPLANE did not involve hardware but again, demonstrated that Airbus were not of the opinion that "hydrogen fuel cells for airliners were found to be impractical over forty years ago," again a point of issue.

    I don't recall weight being a hinderance to hydrogen fuel. Rather it reduces the weight of fuel which is an enabling situation. However it is correct to say that the aviation industry are not rushing to embrace this technology. As I remember, the CRYOPLANE report was suggesting 2015 as the timing for hardware to begin working for a living but that conventional feuls would retain a price advantage for some period.

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  5. Regarding hydrogen fuels - aircraft (and transport in general) have certain needs, among them sufficient energy density in the fuel to pack in enough for a reasonable trip while still having room for occupants and cargo. 

    Considering the issues with hydrogen storage density, I suspect synthetic fuels created with renewable energy (Jensen et al 2007 published in the "International Journal of Hydrogen Energy", for but one example) will be a more viable path for transport. 

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  6. I'll note that current analyses indicate that overbuilding capacity in wind and solar is more cost-effective than building energy storage into the grid. If that continues to be the case, excess power when available could be used for additional synthetic fuel production, effectively becoming energy storage for a large sector of the economy. 

    Whether or not that diversion methodology makes overall economic sense will depend on whether syn-fuel production facilities can afford to operate part-time, though, and I don't have numbers on that aspect. But syn-fuels from renewable power do appear workable and economic. The US Navy has considered this for fueling their carrier aircraft, producing syn-fuel kerosene from reactor power on the move to extend carrier mission duration, at a cost of ~$6-7/gal. - apparently the amount of fuel for the aircraft becomes a limiting factor. 

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  7. Stranger - to be honest, I didnt see the date on that article. However, the description of their current technology says they are still based around same slow speed direct drive annular generator, but I also note comments that their technology is considered expensive compared to neodymium-based systems. Still, as 4th largest player world wide and with 40%+ of German market, they are not exactly a bit player.

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  8. Mancan18, I don't even know what is not my opinion, still your assertion is a big one. So, let me approach it from your concluding argument. CFCs could be controlled because they are inconsequential, replaceable, and there are not huge economic interests behind them. FF are all the opposite. The article, and this wonderful 107 page paper behind it argue that they are replaceable, and rather easily if 150 years of infrastructure is to be replaced in 35. I argue the same as this paper in my book, but on the basis of much cheaper technology with overwhelming benefits.
    Fossil fuels without tax are far better than most renewable technologies; my opinion from similar study as yours. The paper proposes a road map to give policymakers a sense that there are alternatives.
    So, if a carbon tax is imposed, we know there are viable alternatives.

    There are many points of contention, of course, but its a good starting point. I would allow that FF will not be easily replaced but its a duable task.

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  9. The discussion about using hydrogen fuel cells for airliners does not consider the overall feasibility. Producing vast amounts of hydrogen by electrolysis of water woul use up electrical energy. What would be the source of that energy? Also, the hydrogen would have to be liquified (by a cooling system) for transportation and for storage on the airliners.

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  10. @ PluviAL 57, 58.

    The value of this article is that it shows that the world can move to WWS to replace FF, if it wants to, and I think most of us do want to despite the powerful vested economic interests against doing so. Also, we will have to do so within a little over 100 years anyway due to the depletion of FF resources, even if the economic forces against doing so triumph at Paris like they did in Copenhagen on the back of the GFC. Perhaps, what is happening economically in China at the moment will impact the world to the extent that Paris also ends in failure. Acting now rather than waiting till FF resources are depleted will mean the difference between restricting CO2 to "manageable" levels to putting CO2 levels up to over 800 ppm with all the projected climate calamity and uncertainty that this means. Based on the mainstream acceptance of technology in the past, like cars, aircraft and computers, it will take around 30 years anyway, and these technologies were driven by the very wealthy taking up the new technology. Transitioning from FF technology to WWS technology is not being driven by the very wealthy because, unfortunately, this time it is not seen as some trendy plaything but just an extra short term expense, even though the long term cost is much larger if nothing is done. It does mean that Governments do need to act in the interest of us all so that the huge long term negative externalities of not acting are avoided. Sadly, those who matter, the very wealthy, wield far more politcal influence than their numbers suggest. I hate to be pessimistic but until they get on board, very little will be done except for some token policy or effort. I guess something is better than nothing, but it is unlikely to be to at the levels that are needed to avoid the worst IPCC projections. I still try to remain optimistic, because it is all you can be.

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  11. Denisaf,

    Please read the OP.  The electricity will come from wind, solar and other WWS resources.  The energy to make and liquify the hydrogen is included in the calculation.  Some pipelines may be needed for hydrogen but the hydrogen might be made where it is needed with power from transmission lines.  If the electricity was used to make liquid fuel (as described by KR at 56), the fuel could be shipped in existing pipelines.  Liquid fuel releases more pollution when it is burned but no changes in current airplane technology are required.

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  12. MA Rodger, point taken on adressing the arguments and concerns of the other poster. Back to the meat of the issue, the article you linked on the cryoplane specifically indicates that the hydrogen has to be liquefied (hence the name) and that, even in that state, it has a lower energy density than hydrocarbon fuels, which leads to the higher weight necessary to achieve a useable range. Personally I am skeptical of hydrogen as practical solution to power large, long range aircrafts, and I think that producing hydrocarbon fuels through processes that will capture atmospheric carbon may be a better solution.

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  13. Synthetic fuels created with renewable energy should be close to pollution neutral the hydrogen and carbon in synfuels come from the environment, and go back to the environment.

    And I only qualify the statement slightly because the heat of combustion also leads to NOx, unused hydrocarbons and thus ozone, and some particulates burned off the engine components. But that's really small change compared to the GHGs and even SO2 emissions.

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  14. Denisaf - Please read #55 and #56 regarding hydrogen as a primary transportation fuel, and why there are alternatives.

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  15. PhilippeChantreau @62,

    On the weight issue, perhaps you do not appreciate the fuel load of a modern airliner. The ubiquitous Jumbo Jet has a max fuel capacity 43% to 49% of it's max take-off weights, far greater than the structural weight. Using hydrogen would halve these fuel loads but at a price. The first problem is the need to keep the fuel in big deep tanks to reduce the warming of the cold fuel. That means conventional wing tankage has to be replaced by fuselage tanks but that is where the fare-paying passengers & freight usually sit. And with hydrogen more bulky, the fuselage would have to be bigger. The main design consideration would then be the aerodynamic cost of a big fusilage rather than its weight. What CRYOPLANE was saying is that these design considerations are feasible. But the convertion to using hydrogen would be a leap for mainstream commercial aerospace. Certainly the industry as a whole is talking Plan B - getting a 50% reduction per seat/mile in fossil fuel use by 2050 (or whenever) and making that it sound like they are thus doing their bit to counter AGW. Of course with passenger growth, the whole thing turns to a nonsense. The use of bio-fuels would likely allow a partial substitution of fossil fuels through time. Myself, I kind of get the impression that its the fear of the conversion to hydrogen that the industry is baulking at, not the actual technology itself.

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  16. Plastics are made from certain fractions of petroleum. I have not seen any mention of how our demand for them would be met or replaced. The challenge goes way beyond using a cotton shopping bag - just look at all the surfaces and objects in your car, on your desk, at home and at your workplace.

    I'm not objecting to the direction we have to move. Just trying to get my head around what for me is an astonishing premise in the original article.

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  17. MA Rodger, as a long time pilot and flight instructor (although on light airplanes). I do appreciate the fuel load of modern airplanes. As someone familiar with the basic aerodynamics of flight, I also understand the relationship between weight and lift requirements.

    The problem of all alternate ways to power aircrafts is energy density, which is very high with hydrocarbons. Hydrogen has a greater energy density per mass, but a much lower energy density per volume, and carrying it at the kind of pressures that would alleviate this problem requires heavy steel tanks. Liquefying it is the best option but carries its share of problems. Here is a excerpt from the source you cited:

    "A key issue was to model the liquid hydrogen fuel system architecture - per unit of energy, liquid hydrogen has four times the volume of kerosene - so fuel tanks four times as large needed to be fitted in, or on to, each aircraft category. Modelling showed that, owing to the larger exterior surface area needed to accommodate the fuel tanks; energy consumption would increase by 9% - 14%, as would the maximum take-off weight. Overall operating costs would increase by 4% to 5% due to the fuel alone."

    I did not misread this at all. Vast reservoirs containing a much lighter fuel but way more total volume of it. Bulkier and heavier airplane because of the additional storage volume.

    Everything in an airplane has a cost. Any item is weight for which lift has to be generated. Large areas to accomodate large volumes of fuel imply more sheet metal, hence more weight, even if the total fuel weight is the same. Large areas also mean more drag, so more energy required for taek-off, climb and cruise. More weight means sturdier landing gear, which itself will have to be heavier as a result. Etc, etc.

    Then of course, there is the issue of having fuel in the structure in the event of a crash. Engineers also have to assess the survavibility of a forced landing. Powering an large transport airplane is not a benign problem. I have no particular attachment with any solution.

    From purely technical considerations, I remain of the opinion that synthetic hydrocarbon fuels capturing atmospheric carbon are a better option in the short and medium term than hydrogen. And that's not even considering all the infrastuscure associated with commercial transport airplane operations, another non benign consideration.

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  18. PhilippeChantreau @67,

    You get me re-visiting the Cryoplane Report because what you say is familiar but not complete. The summary of the report states:-

    Following features resulted from comprehensive calculations and parametric studies for the above listed rage of aircraft categories.

    ①  Due to the bigger wetted surface of the aircraft due to H2 storage in pressure vessels the energy consumption would increase by 9% to 14%.

    ② The OWE (Operating Weight Empty) may increase by roughly 23% by having additional tank structure,

    ③ while the difference of the MTOW (Maximum Take-Off Weight) will vary between plus 4,4% to minus 14,8% depending on the aircraft configuration and mission.

    All this will result into an increase of the operating costs by 4% to 5% caused by fuel only.

    The numbers for ΔMTOW were given as:-

    Business jet -5.2%
    Small Regional a/c +0.3%
    Regional prop a/c +4.4%
    Regional jet a/c -2.4%
    Medium range a/c -2.7%
    Long range a/c -14.8%
    Very long range a/c -1.6%

    Thus the reducted weight of fuel load equals or exceeds the extra weight of the unloaded a/c in all bar one circumstance. Thus, I was mainly correct but perhaps overly optimistic with my all-encompassing "far greater than the structural weight" comment @65.

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  19. ianw01 - using petroleum to create plastics by and large is binding the carbon rather than releasing it into the atmosphere. The problem is petroleum is using it for energy. I dont see 100% renewable energy as being incompatiable with continuing to use oil for plastics.

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  20. MA Rodger, correct. The extra drag is still there and I would be interested to see how airplanes whose mission traditionally requires cruise just below the transsonic range will fare (airliners and business jets). Few people realize when they fly that the safe airspeed window for an airliner at cruise altitude may be only 20 or 30 knots wide. Beyond that lie the risks of strucutral damage or controllability problems, below that a stall waits for you; high altitude stalls are no fun and recovery will likely put you in overspeed, with the issues I just mentioned.

    In any case, we would be looking at an entirely new generation of airplanes, built from scratch, with an equally new infrastructure to support them, and a blank slate on safety. Such a transition would take a lot of time and be a little dificult to bridge. Currently existing airplanes can be relatively easily converted to use carbon neutral fuels, already have their infrastrucure, and their development includes all the improvements made every time there was an accident. These are important considerations. Airplanes are always compromises, the best possible for the type of mission to be flown. How we will power them will likely be that way too. I'm all for the best possible solution.

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  21. @Michael Sweet

    My numbers for Nuclear power are accurate and for wind power are reasonable.  For nuclear power, average capacity factor (including outage time) has hovered right at 90%.

    As for wind power, I still think 25% is a reasonable estimate, though there are numbers out there that are all over the board:

    Also several sources of data from 2008 suggest Europe was struggling to meet even 20%.  So as we add wind turbines, there is the liklihood that as less optimal locations are selected the current USA CF declines from the current values.

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    Moderator Response:

    [PS] Fixed link. Please use the link button in the editor to create links

  22. scaddenp et al.

    Arriving at this discussion somewhat belatedly, it seems appropriate to point out at this juncture that Ricardo said recently they have designed a low cost, rare earth free EV motor:

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  23. I'm a bit late to these comments too. The idea that renewable energy needs rare earths is outdated. As somebody already pointed out it is not used in normal solar panels. What has not been mentioned is that modern gearless wind turbine magnets only use .7% or less dysprosium and will soon use none. The neodymium may be considered rare but there is an endless supply throughout the world making the term "rare" not appropriate. For reference read the last three paragraphs of this BBC article:

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  24. Also much larger turbines are being built and at 140 meters their capacity factors usually exceeds 60%. Furthermore the wind at that height is available in many more locations. 

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  25. "A critical review of global decarbonization scenarios: what do they tell us about feasibility?" from that article "Given the multiplicity of feasibility challenges associated simultaneously achieving such rapid rates of energy intensity improvement and low-carbon capacity deployment, it is likely to be both premature and dangerously risky to ‘bet the planet’ on a narrow portfolio of favored low-carbon energy technologies."

    Also from the journal "Nature Geoscience" - "Metals for a low carbon society"

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  26. tder2012 - Personally, I do not expect the path to low-carbon energy to be simple, and many of the proposals for accomplishing that are indeed more thought experiment than detailed proposals. 

    However, if we were to implement costs on fossil fuels commensurate with their impacts, such as a carbon tax, accompanied by government policies supporting rather than undercutting renewables, I expect the move to low-carbon energy in all sectors of the worlds economies will occur simply due to the profit motive. 

    The second reference you put forth, Vidal et al 2013, has as its abstract:

    Renewable energy requires infrastructures built with metals whose extraction requires more and more energy. More mining is unavoidable, but increased recycling, substitution and careful design of new high-tech devices will help meet the growing demand.

    Given the doubtful tone of your post, I would have to note that the referred article is actually quite optimistic. 

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  27. @scaddenp (#69): Agreed, up to a point. Remember that only a fraction of  petroleum is suitable as feedstock for plastics, and that processes such as cracking take a lot of energy.  Doing something other than burning the non-feedstock fraction will take considerable discipline, or incentives.

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  28. So you have much smaller systems that burn (yes, that produces CO2) fractions not useful for plastic to power the cracking (and cogenerate power while at it). If this is the only CO2 from FF in use, then I rather suspect the planet will cope ok (and certainly a lot better than current usage). The refining process would be different when the target is not to produce as much transport fuels (ie less cracking) as possible. Tuning for petrochemical production would be different.

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  29. Slightly of-topic but perhaps relevant to the mining comment KR references.

    A discussion on Peak Mining.

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  30. Joris,

    This thread documents that renewables can provide 100% of all power.  Even the most optimistic nuclear supporters do not claim they can supply more than half of electricity.  Provide evidence to support your absurd claims or go away.  

    [Moved here from another comment by moderator]

    In response to your false claim that nuclear has suffered from bad press, nuclear proponents need to stop whining.  Where I live in Florida the utility executives do not care at all about Greenpeace and they control the decisions.  Your claim is false on it's face.  Stop wasting our time.  The more you rant, the less people listen to you.

    Nuclear is not being built because it is uneconomic.  The current plants being built in the West are grossly overbudget and way behind schedule.  I have seen the Norway plant described by a nulcear engineer as "unbuildable".  So much for generation three.  Wind is cheaper than existing nuclear in most of the USA already, how could nuclear possibly pay for a new plant that takes a decade to build?

    Only Barry Brook, who is an ecologist not a nulcear engineer, publishes papers suggesting nuclear can be useful.  He estimates that by 2060 half of electricity can be supplied by nuclear.  This is too little too late.  He does not estimate any costs, probably becasue it is too expensive.  Renewable is ready to provide all power, ten times as much as estimated for nuclear by optimists who are not even nuclear engineers.  If you cannot find published papers to support your wild claims go away.

    I read a lot of papers about nuclear while doing the background for the renewable review linked above.  People who research future energy supplies have given up on nuclear.  It is uneconomic and cannot be built in the time necessary to do anything about AGW.

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    Moderator Response:

    [PS] Snipped section from comment in alternative place moved here.

  31. Hello Michael,

    Thank you for the research and thought you put into this article. This is what I have been looking for - an overall plan that addresses at least some of the logistics of replacing fossil fuels with renewables to supply our energy needs. Certainly, there are many details to be worked out, but this plan offers hope and a path forward.

    I am preparing a presentation and would like to be ready for questions and comments. There are two questions that come to mind in regard to "using wind to generate 50% of energy."

    I am wondering about the CO2 emissions from the production of steel, etc. for the building of the initial wind turbines. I assume that the emissions for manufacturing wind turbines is more than offset by the savings of CO2 emissions compared to using fossil fuels for providing future energy. During the transition period, if the steel and manufacture of a wind turbine depends on current methods using fossil fuels, do you know how long it takes for a wind turbine to "pay for itself" in terms of CO2 emissions? (As a sub question, it would also be interesting to know how long it takes to pay for itself economically.)

    My second question is, "What about the birds and bats?" It seems their learning curve in regard to the dangers of wind turbines is pretty much vertical. I found an article indicating that wind turbines kill relatively few birds, at least compared with other man-made structures. And improvements in design and location have greatly reduced bird mortality. However, the number of wind turbines recommended by Jacobson must surely be bad news for birds.

    Has anyone done a study to determine the effect on our ecosystem from such an increase in bird mortality. And could this bring about extinction of some species?

    I don't expect you to "have all the answers", but you do seem to have a good handle on what information is available.

    Thank you for the way in which you care for the earth and all who live here. Yours is truly a noble career.

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  32. Sharon,

    Sorry for the slow reply.  It seems to me that you have found reasonable sources of information.  Keep reading new material as much as possible.  Information on this topic almost always comes with a slant (including information from me).  Unfortunately, Skeptical Science does not post a lot of material on solutions, their objective is to deal with myths about Global Warming.

    The Jacobson paper discusses the energy payback time for the manufacture of the materials to generate all power using renewables.  Wind generators pay back in less than a year.  As more renewable energy is built the remaining turbines (or solar panels) come from renewable energy.  This does not appear to me to be a major problem. There are more questions about the total cost and generating backup power on windless nights (the backup power is one of the major costs).

    I have seen the article you linked about birds.  I accept the experts view that wind generators do not kill many birds.  If they build as many turbines as Jacobson plans that will have to be one issue that is carefully monitored.  I have heard that newer, taller wind generators (as tall as 700 feet to the rotor) are so tall that most birds fly under them.  Migrating birds and raptors might still be an issue.  Wind operators have other plans that might help (like stopping turbines when raptors are in the area), we will have to see.  We cannot stop such an important build for an issue that is currently not a problem.

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  33. michael sweet at 83 on "Trump country costs" blog

    I now understand why you commented that there have been questions raised about the cost estimates in the Jacobson study.  In the interests of balance, I would have hoped  that you would have been more clear on how much this study has now been put into question so recently.

    My specific information (although first highlighted by a reread of the Shellenberger article in Foreign Affairs referenced earlier) comes from a recent Scientific American blog which can be found here:

    The Scientific American blog states that the National Academy of Sciences in a June, 2017 paper, authored by 21 leading energy researchers, has made  a "scathing critique" of Jacobson's analysis and found that the analysis “used invalid modeling tools, contained modeling errors, and made implausible and inadequately supported assumptions.”

    The largest error is found in  Jacobson's calculations as to how existing and future hydro could provide the "mixed grid" (buffering)  to support wind and solar power when they were not available.  Here is the comment from Scientific American:

    "The most glaring of which is the assumption that U.S. hydroelectric dams could add turbines and transformers to produce 1,300 gigawatts of electricity instantaneously — equivalent to over 16 times the current U.S. hydroelectric capacity of 80 gigawatts. A previous study by the U.S. Department of Energy found the maximum capacity that could be added is just 12 gigawatts — leaving a 1,288 gigawatt deficit, or the equivalent of about 1000 large nuclear or coal power plants running at full power."

    So, as recommended by this article, it would seem a great deal of work remains to be done to determine how we can move from fossil fuels to a source of reliable clean energy.  This article suggests many avenues including a continued examination of nuclear power.

    I would like to discuss EROI and the Weissbach paper and criticisms by Raugei et al.  My plan is to use this stream as well. 

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  34. Moderator and michael sweet

    I have not had any reponse from michael sweet on my post on this thread on September 12, 2017 referencing the paper published by the Proceedings of the National Academy of Sciences in June 2017 which is severely critical of the Jacobson paper which was the subject of this blog originally created by an article on the Jacobson study posted by michael sweet in August 2015.  I have only recently realized that michael sweet has indicated that he is not prepared to respond to any of my posts.  I am not completely clear why.

    I think in the interests of balance that SkS should acknowledge the criticisms that have been made by the NAS paper.  I have now read that paper which is available publicly at

    Although the 23 scientists, headed by Christopher Clack (of NOAA), are in complete support of effective ways to wean our society from fossil fuels by a combination of solutions (which would include a large solar and wind component), this paper effectively states that the Jacobson study is so full of modelling errors and implausible assumptions that it cannot credibly be used in any way to advance the questions that need to be answered to move this examination of alternatives (and their costs) forward.

    I have recently praised the SkS website (agreeing with Joe Romm on a Sam Harris blog following Harris'  interview of Romm on climate change) that the SkS website does a good job of providing valuable information.  I may not agree with (or understand) some of it but I find it reasonably balanced.

    In the spirit of providing balanced information,  I would hope that SkS would make its readers aware of the serious criticisms that have been levelled by eminent scientists at the  Jacobson 2015 study published by the Proceedings of the National Academy of Sciences (PNAS).

    I do not think the Jacobson study should ever be referenced by any contributor to this blog without a caveat pointing the reader to the criticisms presented by this paper in June 2017.

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  35. NorrisM , I thought I ought to transfer some of my reply to you about the Jacobson paper, from where you had mentioned it as an en-passant footnote in "another thread" :-

    I had said :

    "... Jacobson draws a long bow into the technological future.   IMO his emphasis on hydrogen fuel was way over the top, and as you rightly say his hydro-power summation is nowadays shown as a big error.   #Nevertheless, none of that is in any way an excuse not to press ahead with wind/solar conversion at a much faster rate than we are doing currently" .

    The Jacobson study continues to have value as one of many talking-points regarding future developments . . . despite its lack of perfection.  Yet it is always important that we "keep our eye on the ball" of what we need to do now to tackle the ongoing AGW crisis.

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  36. Why don't we shift the discussion of renewable energy to here.  It will be on topic.

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  37. michael sweet @ 86

    Happy to continue the discussion here.  Obviously we have previously discussed the Jacobson paper at some length (and some of the peer-reviewed criticisms of it) but your point is well-taken that all proposed 100% renewable energy solutions have to have come up with an answer for the agricultural sector.    

     Jacobson's study was based on the United States.  Somewhere else I provided a interview with an wind and solar expert in California who had advised the California power authority who felt we could only realistically get to 80-20 in the US.   But this is in the United States and even with his interview I had no sense of how long that would take even if we had the Democrats in power.

    Even in North America this is not going to be cheap.  I recently walked into the Tesla dealership to see how much my sister's Model X (I think that is the new one) is going to cost her.  I thought she had told me ballpark $35,000 Cdn.  My understanding is that by the time you walk out of the dealership you will be looking at somewhere between $50-60,000 (before taxes).  Elon is not appealing to the working man.

    But then we move to the Chinese or Indian farmer.  Where is the grid system that Jacobson works on in his US analysis?  Just how many years will it be before China has moved from coal to wind, solar and nuclear energy sufficiently to allow tractors to operate on batteries?  And when are the trains going to be converted to electrically run systems to transport the goods to ships?  And when are the ships going to be converted to electric powered engines?

    I acknowledge that all of this can happen but it will take a lot of time.  

    There is simply no way we can move from ballpark 85% fossil fuel energy production in the world to even 50% let alone 20% as projected for the US by this California expert.  Right now, wind and solar in the world is no more than the source of 5% of the world's energy production.   I think it is more like 2-3% if I am not mistaken.

    I think the real difference between what I will call the "warmists" versus the "luke warmers" is not really a difference on the science. Both sides accept that the planet is getting warmer and CO2 emissions constitute at least 50% of the warming.  The real difference between the warmists and the luke warmers is a disagreement on the ability of the models to accurately predict what will happen after 2050 and therefore how much time we have to deal with the problem.  That is why I personally want to focus on sea level rises based upon observations.  But I guess to continue this discussion we have to move to even another blog.  But is that not what this all comes down to?  We cannot agree on: 1. whether the temperature increases in RCP 8.5 are realistic based upon the limited ability of the models to replicate the climate; and 2. whether the assumptions of fossil fuel use in RCP 8.5 are realistic.   As well, all the "scary stuff" in the models seems to take place from 2050 onwards so we really cannot even point to any spectacular failure of the models today.  The models are not falsifiable because we have to wait 30-50  years for the serious consequences.  Moderator:  If you "snip" this last paragraph for again being off topic could you suggest another thread on models? 

    So much of this comes down to how much can we trust the models.

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    Moderator Response:

    [DB] Off-topic, sloganeering and arguments from incredulity snipped.  For SLR discussions, continue using the thread you had been (you know better than to try to throw other threads off-topic).  For models, learn to use the Search function in the upper left corner of every page here and select the most-appropriate thread from the results.

  38. Norrism:

    The papers I have referred you to claim that we can convert to 100% renewables by 2050 if we try hard. 

    If we continue to accept the lowest possible estimates for possible damages and the fossil fuel industry estimates for the cost of switching to renewables than it will appear to be difficult.

    Both Jacobson and Smart Energy Europe estimate that it will be cheaper to switch to renewables than to continue to use fossil fuels.  Economists like the Stern Report say it will be much cheaper to switch to renewable energy than to continue ot use fossil fuels (and the cost of renewables had shrunk dramatically since then).

    We have to decide: do we listen to neutral scientists whose primary care is the future of their families about what is best to do or do we listen to oil industry executives who only care about how big their bonuses this quarter are?

    Plans like those I have linked exist for all the countries of the world.  The fossil fuel industry crying for farmers in India is just so much BS.  Look at how many millions of Indians die every year from fossil fuel pollution.

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  39. Geotim,

    Many analysis indicate that there is much more than enough renewable energy to power the netire world.  There are ongoing discussions about the best way to store power to use during periods of high demand with low wind and sun.  The OP describes Jacobson's plan which uses hydrogen as primary storage.  Other plans (Connolly) use methane or methanol as primary energy storage. 

    Jacobson's plan has been criticized as using too much hydropower.  Connolly's plan would use existing methane peaker plants to supply backup (much of the methane could be stored in existing facilities).


    One thing I can tell you for sure: the energy system is very complicated and difficult to understand.  

    According to both of these plans, renewable energy will cost less than fossil energy.  In addition, renewable energy will result in dramatically reduced pollution.   Lower pollution will mean less disease and early death.  If you add the health savings to the energy cost it is a tremendous cost savings.  Of course, the recent Trump energy plan assigns a zero value to human lives lost.

    Think it through: if renewable energy cannot supply enough power for the entire world, what will people do in 100 years after all the fossil fuels are used up?  Do you think they will all go live in caves?  Everyone expects future people to solve this problem.

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  40. Nigelj,

    I thought this was a  better thread to discuss renewable energy.  At RealClimate it takes several days for posts to be readable and you post both places.

    I read your reference on "three weeks of storage". Original paper here (Shaner et al).  I recognized at least two of the authors (Davis and Calderia) as constant nuclear proponents.  

    Although I am not a researcher, I notices several obvious problems with this paper.

    1) The paper only looked at the electrical system.  Renewable energy researchers showed at least 5 years ago that the bigger the system the less relative storage is needed.  Thus electricity only requires the most storage, electricity + transportation requires much less and electricty + transportation+ heat + industry requires the least.  All North America requires less storage than the USA only.  The finding of Shaner that storage is required for this system is similar to what I recall from old articles.

    We cannot compare this result to Jacobson et al 2018 or Connelly 2016 because both those articles look at ALL POWER.  

    2) Shaner et al use only solar pv and wind in their simulations.  Why would anyone care about a system that leaves out existing hydro, geothermal and pumped hydro (originally built to balance nuclear power)??  Obviously, no one will tear down existing resources.  The "three weeks of storage" is for a system that has no hydro, geothermal or pumped storage, not for any concievable system built in the USA.  This seems like a fatal error to me.  Certainly "three weeks" is not relevant.  Hydro alone would significantly reduce this storage.

    3) The model uses wind speeds at 50 meters for their analysis.  It is well known that wind is stronger and more consistant the higher above the ground you get.  Jacobson 2018 uses wind speeds at 100 meters.  Current 1.5 MW turbines have hub heights at 65 meters.  Blades reach to 100 meters.  Design specifications for new 5 MW turbines is 88 meters to the hub.  The blades reach 64 meters higher (to 152 meters).  I am not sure what the best height to use is for future turbines but 50 meters is obviously much too low.  This is a fatal error to me.

    It seems to me that Shaner et al is designed to find the most expensive renewable energy system.  This makes nuclear look better since it is so expensive.  The paper suggests using nuclear to reduce system costs in the conclusion.

    Most people are interested in finding the cheapest system cost.  Shaner et al is not interesting to those who seek the lowest cost.

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  41. This article provides the abstract of 47 peer reviewed articles that describe how to convert the economy to 100% renewable energy.  Many of them give specific plans for building out a 100% renewable system to provide all energy to either a large country or a continent. 

    This link is useful to find references to support renewable energy or simply as a source of background reading to inform the reader.  If you want to read beyond the abstract use Google Scholar to look for free copies.  If you are reading challenged you can simply read the titles of the papers and figure they show what the title describes.  This list is probably up to date in 2019.

    Hat tip to Postkey who pointed me to this article.

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