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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 1 to 50 out of 91:

  1. Still if you do the math, it takes about 1800 Wind turbines rated at 2.5 MWe (capacity factor about 25%) to replace a single 1100 MWe baseload plant (capacity factor >90%).  That's a lot of land coverage.  That means there are still some significant practical hurdles to get to where this paper suggests.  It is not entirely a political problem.  Solar, hydro-electric and others all have their issues as well.

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  2. I'm assuming that this paper assumes current electrical uses projected into the future. However there are off grid communities in existence that consume 16% of the electricity normally used in the general area.

    This ecovillage has all the anemities and appliances of a middle class house with homes that are conventional looking (no "earthships"). 10 inch super insulated walls, led lighting, underground heating and cooling tubes and passive solar design make this dramatic reduction possible.

    With such a massive reduction in electrical and energy usage we'll only need one sixth of our current energy usage for homes. 50 mpg hybrid cars will take care of the rest.

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  3. That 16% needs to be seen in context of what proportion of total energy consumption is in residential home use. In NZ, it is about 10% of energy use though I expect it to be higher in places with more heating/cooling needs and/or less transport costs.

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  4. @ scaddenp #3.

    Yes, I should have thought of my answer more carefully. My goal, however, would be for an 80% reduction in fossil fuel energy use within the next 20 years (I know, I'm dreaming).

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  5. Knaugle,

    Jacobson et al. "do the math" in their paper.  As described in the second pargraph of the OP, approximately 1.6% of land area would have wind generators widely spread out.  Farming or other land uses would take place between the generators (the actual land footprint of the turbines is small).  If you put the generators in the most efficient places it would take less generators but that is not quantitated (it would also cost less).   You could put more wind generators at sea and reduce the onshore wind even more if that is desirable (offshore is more expensive but the wind is more consistant).  

    Your quote of 25% capacity for wind is too low.  Your argument is inconsistent since you used the maximum output for nuclear and the minimum for wind.  You need to use comparable estimates for both if you want to make a fair evaluation.

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  6. @ villabolo .  re efficiency improvements. Note in the graph that there is a planned reduction in energy consumed of about 33% from todays levels (2.4 TW down to 1.59 TW), or more than 1TW from predicted business as usual levels (in 2050). Most of that saving is from switching to electricity, but some from efficiency improvements.

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  7. As usual, Jacobson et al. miss the boat by excluding nuclear power from their analyses on the thinnest of excuses. (Water use is the excuse, even though hydropower uses vastly more water than nuclear yet somehow manages to make the cut. In other words, Jacobsen et al. are playing politics instead of science.) 

    Meanwhile, the Deep Decarbonization Pathways Project found that the high-renewables scenario, similar to the plan Jacobson et al. favor, would cost about four times more than the cheapest pathway, which happens to be the high-nuclear pathway. (That's strongly dependent on the future price of fossil fuels, but taking the median in each case.)

    It will be interesting to see how the upcoming paper on grid revamping will turn out. The most recent HVDC line in North America, the West Alberta line (opened last March) cost $6 million per mile for a 1 GW line, and that's through relatively unpopulated country where rights-of-way are cheap. At that price, it's cheaper to build a nuclear plant next door that it is to transmit wind power 700 miles.

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  8. keithpickering, actually from my reading they say that nuclear was excluded because of cost factors and construction time. I didn't see anything about water use of nuclear power... let alone that this was the reason for excluding it.

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  9. Nuclear is nowhere close to 33-40% efficiency .... In fact it's not even double digits

    Only 5% of the potential energy in a nuclear fuel rod is used while the other 95% goes to waste making Nuclear Waste waste on more than one level. Then you add the inefficiencies in the mining process, inefficiencies in the refining process, ineffeciencies in the steam boiler and finally the inefficiencies of the turbine generator itself you'd be lucky to hit a 1% efficiency when PROPERLY CALCULATED 

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  10. Certainaly "renewables" could power us but there is no way to get there from here without destroying the biosphere in the process. A shift of that magnatude would require massive fossil fuel burning, mining, processing, cement, and every other industrial process that is killing us and that would be in addition to all of the industrial processes that we now have happening continuing to function in order to not collapse the global economy.


    We are at a point in human evolution where every solution to a problem creates an even bigger problem that we will need to solve for later.

    So what do we do? LESS!!!!!!

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    Moderator Response:

    [RH] Sloganeering snipped. If you're going to make such extreme statements you're going to have to back them with some actual data and figures.

  11. All the human-made things in our world have an industrial history. Behind the computer, the T-shirt, the vacuum cleaner is an industrial infrastructure fired by energy (fossil fuels mainly). Each component of our car or refrigerator has an industrial history. Mainly unseen and out of mind, this global industrial infrastructure touches every aspect of our lives. It pervades our daily living from the articles it produces, to its effect on the economy and employment, as well as its effects on the environment. Solar and wind energy collecting devices also have an industrial history. It is important to understand the industrial infrastructure and the environmental results for the components of the solar energy collecting devices so we don’t designate them with false labels such as green, renewable or sustainable. This is an essay challenging ‘business as usual’. If we teach people that these solar devices are the future of energy without teaching the whole system, we mislead, misinform and create false hopes and beliefs. I have provided both charts and videos for the solar cells, modules, aluminum from ore, aluminum from recycling, aluminum extrusion, inverters, batteries and copper. Please note each piece of machinery you see in each of the videos has its own industrial interconnection and history.

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    Moderator Response:

    [RH] I've deleted the contents of this comment because the exact same comment is copied and pasted repeatedly around the internet. This would constitute spamming. Please review the SkS commenting policies before posting again.

  12. One of the proposals of this ilk was by Jacobson. Jacobson’s first paper proposed: Starting in 2012 for 50% of the world’s energy we would need: 2111112 machines a year for 18 years which is over 578 machines a day for 18 years which is over 24 each hour, each day, 7 days a week for 18 years and In an email discussion with the second author he proposed that since we do it with cars; we can do it with “renewables”. So all the mining, processing, manufacturing, transporting, installing, two or three times a year maintenance. This is green? This is sustainable? This is renewable?

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    Moderator Response:

    [RH] You seem to be making a very strange statement that installing renewables is not sustainable or renewable.

  13. I really found this article interesting.


    Since wind turbines and solar panels use so many rare earth elements can we expect that future technologies will overcome the huge environmental impacts of mining them?  I know the mining of them in the US is prohibided.  From what I've also read, China may not be as forthcomming with them in the future.  

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  14. A very interesting, and dare I say, optimistic paper. However, while filled with lots of numbers, it seems to gloss over the storage and long distance transmission required during calm winter evenings in the northern states. And if this is the path forward it's time to buy stocks in copper and rare earth element producers.

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  15. sunweb @12.

    It is a lot of wind turbines being discussed but they have to be judged against the alternatives. This erecting of 600-odd turbines a day would yield the same generation capacity as having to build every fourth day one very very large multi-steam-plant coal power-station. You may feel the 2,400 turbines in 4 days is a bigger ask than on giant coal power-station but perhaps you have less understanding of how big such power-stations actually are.

    As a comparison, the daily 600 turbines will contain something like 300,000 tons of material. That's 300,000 tons per day for 18 years.

    That's a lot of material but of the same order as the daily materials required to build a giant power-station every 4 days. This web page shows a relatively small power-station (40% the size I'm working to) using 900,000 tons of concrete & 56,000 tons of steel.

    And those 1,600 coal power-stations built over the 18 years would still need feeding with coal, a combined total of 55,000,000 tons of the stuff, day in, day out until they can be replaced by a better technology. So is it worth discussing this coal solution being green, sustainable or renewable? I think not.

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  16. keithpickering - I don't see anything in the Jacobson et al paper making claims against nuclear based on water usage - do you have a reference for that?

    The Decarbonization document seems interesting on a quick look, but I can't agree with some of their base numbers. They assume 2,500GW of renewables (wind/solar) to match 400GW of nuclear, a factor of 6X, whereas Archer 2007 demonstrated that a mere 19 distributed and interconnected wind plants could maintain a reliable baseload power of 33% their average (47% the yearly average), a factor of perhaps 3X, half of what they sate, simply because the same weather pattern wouldn't cover (and potentially nullify) all of the wind farms at once. 

    Archet et al also discussed techniques for reducing transmission costs by ~20%, with regional concentrators for the wind power and interconnecting to the larger grid from there. But the major impact IMO is in understanding baseload capabilities. 

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  17. Moderator - I don't think installing "renewables"  is sustainable or renewable.  They are extensions of the fossil fuel supply system.  


    All the human-made things in our world have an industrial history. Behind the computer, the T-shirt, the vacuum cleaner is an industrial infrastructure fired by energy (fossil fuels mainly). Each component of our car or refrigerator has an industrial history. Mainly unseen and out of mind, this global industrial infrastructure touches every aspect of our lives. It pervades our daily living from the articles it produces, to its effect on the economy and employment, as well as its effects on the environment.

    Solar and wind energy collecting devices also have an industrial history. It is important to understand the industrial infrastructure and the environmental results for the components of the solar energy collecting devices so we don’t designate them with false labels such as green, renewable or sustainable. This is an essay challenging ‘business as usual’. If we teach people that these solar devices are the future of energy without teaching the whole system, we mislead, misinform and create false hopes and beliefs.

    I have provided both charts and videos for the solar cells, modules, aluminum from ore, aluminum from recycling, aluminum extrusion, inverters, batteries and copper. Please note each piece of machinery you see in each of the videos has its own industrial interconnection and history.

    2 1
    Moderator Response:

    [RH] Reposting a canned comment that was previously snipped for sloganeering is not acceptable.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  18. It isn't spam if it is the researched truth.  If I rephrase it but still suggest the videos with URLs is it spamming.  It is a challenge to the technofantasy that solar and  wind energy collecting devices are renewable, sustainable and green.  I find the same censoring when it doesn't fit the world view of the moderator.


    0 0
    Moderator Response:

    [RH] Moderation complaints are also not allowed here. Please refer to the commenting policy.

  19. I do not think solar or wind energy collecting devices are sustainable, green or renewable.  The reason is that they require a global industrial infrastructure for the manufacturing.  When they must be replaced they will require a similar infrastructure.  When I had to replace the pancake fan in my inverter, it had such a system behind it for manufacturing.  So the sun and wind are renewable but the devices are not.

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  20. Sunweb,

    Most other people disagree with you.  If the energy used to manufacture a solar panel comes from other solar panels than the new solar panel will be sustainable.  Current wind and solar generators are built using fossil power with a little renewable in it.  As more renewable power is built the fraction of power used becomes more and more renewable.  The paper described tells how we can build a system so that all power used is from sustainable sources.  Once they are installed, all economic activity will be done using sustainable power.

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  21. IANW01,

    Storage is not glossed over.  Jacobson uses concentrated solar power with storage for most of their storage.  Managemant of hydro power contributes a small amount.  The system is overbuilt so that all power demands are met 100% of the time. 

    Budischak et al. give specific data for the PJM interconnection (around Pennsylvania)  if you are interested in the Northern states.  Detailed studies have found that it is cheaper to overbuild renewables rather than build a lot of storage.  Budischak generated all their power internally, if they install interconnections to nearby grids they will require much less overbuild.  Budischak also did not use any hydro from Canada for backup on dark, windless nights.  They said using Hydro made it too easy to use 100% renewables.

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  22. I see no biomass in the Jacobson et al analysis, yet there is a potential there that should be ignored. Almost any material can be prepared to be used in a biomass burning furnace, including herbivores waste products. I also think that the share given to geothermal is pessimistic.

    Enhanced geothermal (EGS) should be given more attention. It has low impact, low risk, can function readily as baseload and is not nearly as expensive as nuclear. It looks so good on paper, one has to wonder why we're not pursuing more aggressively. According to the wiki entry, MIT has determined that the US alone has enough potential to power the entire world. It can also use CO2 instead of water, allowing for carbon sequestration. It does cause induced seismicity, but I don't think it's as bad as fracking. It's hard to see why it should represent such a small percentage in the mix as figures in the Jacobson graph.

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  23. @22 PhillippeChantreau

    The model does not include biomass because of the air pollution associated with burning biofuels. The aim of reducing air pollution appears to also be why they are using hydrogen production as a chemical store instead of a methanisation process.

    With regard to enhanced geothermal, currently EGS is falling out of favour because the rapidly decreasing cost of wind and solar is making those sources cheaper than EGS. The weakness of EGS in a large-scale,100% renewable scenario is that its basically a constant power source (similar to nuclear or coal-fired power in current systems). So it can't ramp-up to take advantage of the high-margin periods when generation from wind and solar is low. This reduces its cost-effectiveness.

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  24. sunweb@19 said: "the sun and wind are renewable but the devices are not".  Why not?  Are they somehow used up in the producing of power?  People seem to think that once rare earth metals are mined for solar and wind devices that these materials are no longer available once the devices have outrun their useful life.  That's absurd.  On the contrary, there would be a potent financial reason to reclaim these 'already refined' rare materials during decommissioning, rather than dig up ore's and refine them all over again.

    If this is a new 'fossil-funded denial argument', its absurd on its face.  Wind turbine materials can be reclaimed in the same way gas turbine or steam turbine materials are reclaimed.

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  25. Some time ago I sent a post to Professor Jacobson listing a number of unsound technical items in their proposal in Scientific American of November 2009. Some of those issues are covered in the comments here.

    The suggestion that airliners could be powered by hydrogen was thrown out by reputable researchers over forty years ago but it is included in the proposal. another point is that 'renewable' systems (wind or solar) are made of irreplaceable materials so they can only be a tempoary source of a small amount of electricty. another point is that fossil fuels supply other products that WWS cannot supply.

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  26. @ 19: why does Renewable Energy require any more of a global industrial infrastructure than nuclear or coal?

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  27. denisaf @25...  Well, interestingly, both Boeing and Airbus are currently working on hydrogen fuel cell technology for aviation, with an eye on passenger aircraft.

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  28. Rob Honeycutt@27,

    bozzza was probably referring to the old proposal to burn hydrogen in airliner engines. Of course the material problems, including hydrogen embrittlement of the fuel lines in a machine that shakes a lot, made that very unlikely to be economical, as is the current inefficient energy requirements for generating the hydrogen. Why would people choose to use that much energy for that purpose?

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  29. denisaf @25,

    As pointed out @27, your "reputed researchers over forty years ago" must have grown fat on their own words that they had to eat. Unless you have yourself further words on that subject (and also on the re-use of materials required for solar/wind power given the comment @24), I wish you "bon appetit".

    Your third point, the use of fossil fuel resources for purposes other than that power generation, there is presently much common use of infrastructure etc but I have not heard anybody warning that we would have to keep burning coal, oil or gas if we want to keep manufacturing plastics. So do explain.

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  30. Others have pointed at the glaring defficiences in this paper. Where are the calculations of all the resources needed to build out this infrastructure? Will it be possible to build more, or maintain existing, once 100% of the energy use is from renewables? It doesn't mention whether the electrolysis of water can produce enough affordable hydrogen for those transportation needs that it envisages will use hydrogen (though someone else mentioned hydrogen powered aircraft had already been discarded), at the rate required. And how does the adpotion, or not, of this strategy by the rest of the world affect the feasibility or likelihood of it?

    To me, this seems like more wishful thinking to avoid changing our behaviour.

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  31. @22 and 23 PhilippeChantreau and WRyan,

    WRyan is correct that Jacobson has pollution concerns about burning any carbon containing material.  It seems to me that the scheme described is an optimal system using renewables.  If you were to build trash to energy plants it would be easier to move to 100% renewable energy.  You would have to accept the pollution (which I think Phileppe and I do).  Likewise, if hydrogen airplanes do not work out you could make jet fuel from seawater.  If there are problems supplying baseload power, more EGS could be built.

    This is very positive to me.  It indicates that there is more than one way to get to the target of no fossil fuels.  If we started installing wind and solar as described in the OP, we could make adjustments in the future as issues were discovered.

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  32. TonyW:

    In other papers Jacobson has estimated the amount of materials required for building out their renewable scheme.  Once the generating plants are built it will require less materials and energy to maintain them.  They will produce more than sufficient power to perform those activities.  They show in this paper that enough hydrogen is produced to supply all the needs of society (that is the point of the paper, all energy is produced).

    They have plans on their website for all nations in the world to convert to 100% renewable.  Obviously for any solution everyone has to adopt renewable strategies.  Currently China is ahead of the US in renewable adoption stragegies.  They require renewables to reduce their crippling air pollution.  

    This paper specificies what needs to be done for the largest economy in the world.  It follows that the rest of the world can adopt similar plans to reach the renewable target.  Plans will vary from country to country just as they vary from state to state depending on the local resources (Norway has a lot of hydro and Australia has a lot of sun).

    To me your objections amount to "I doubt it" without any data to support your position.

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  33. I think that apropriate technology can limit the amount of particulates emitted by biomass combustion. Jacobson et al proposes one specific scenario and attempts to show that the numbers can line up, and that's fine. However, what will happen in the real world will be another story.

    I don't know if either governments or utilities will ever be persuaded to not have a constant baseload, in which case EGS is the answer. I also find it a little skewed to ignore biomass because of pollution, when solar at the scale described in the paper will require mining minerals on a scale bound to create serious environmental problems. Of all the possible solutions, I find EGS and off-shore wind to be the least destructive.

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  34. Stranger. "Since wind turbines and solar panels use so many rare earth elements". Can you expand this please? I didnt think conventional solar cells use any rare earth of significance, and usage in turbines would seem to be the same whether the turbine is driven by coal, nuclear, hydro, geothermal or wind? Electric cars are another story...

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  35. Interesting article but only seems to concentrate on the US.

    However, I'm not sure that it deals with all the issues.

    It seems from the article that transforming energy generation to 100% WWS is theoretically possible using existing technologies, despite all the land area, transmission, manufacturing, material recycling and cost issues that need to be considered.  However, I saw no mention of the increased generating capacity projections that will be needed. Local areas may well be able to be transformed to 100% WWS, however, it does not overcome the basic problem of reducing fossil fuel emissions to zero from the current global 83% reliance on using fossil fuels for power generation, while at the same time meeting the global demand for power in the future. In the 1950s, the global demand was about 3 TW. By 1990 it had risen to 12 TW. Today, it is 18 TW and it has been projected that  capacity will need to rise to over 30 TW by 2050. Simply saying that we will need to reduce demand is not an answer. That means dooming many developing countries to a permanent state of poverty.

    More efficient technologies and methods are needed if we (the human race) are to reduce our reliance on fossil fuels. We most certainly need to reduce our emissions. However, if we are to realise that 30 TW figure by 2050 while keeping our emissions down to a level that will keep  temperature increases below 2 degrees won't be an easy task. We will need all technologies, not just WWS. We will also need 4/5th generation nuclear, like the thorium reactors which consume all nuclear waste. We will need hydrogen as well as more efficient WWS technologies. We will need each private residential household to be self-sustaining and contribute any excess capacity back to the grid. We will need more power efficient consumerables. We will need to rebuild our infrastructure where our concrete urban areas and road systems become solar energy sinks and the water from our urban drainage systems can also be used to generate power. Even new corporate entities, where the price of a share could also include the technology to make your household self-sustaining and able to  contribute to the grid, may also need to be explored; rather than simply relying on old corporate models, where the company builds a power station, whether it be a solar array, a wind farm, a nuclear power station or a coal fired power station, and sells power through the grid. It seems all technologies will be needed if we are to get anywhere near what will be required globally. It should be the high tech first World nations that are leading the way. Unfortunately, there are too many political ideologues stopping them from doing so to the extent that is needed, because they don't even recognise that there is a problem. In doing so they are threatening the very way of life that they want to protect.

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  36. Sadcap scaddenp, Neodymium, terbium and dysprosium are essential ingredients in the magnets of wind turbines.

    Solar panels need tellurium

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    Moderator Response:

    [JH] Link activated. 

    [RH] I believe you're addressing scaddenp, not "Sadcap." 

  37. Stranger, thin-film solar cells use tellurium, but the normal solar PV installations do not (and CSP does not).

    I am well aware that turbines use those metals, but do you have data to support use per MW is higher in wind turbines than in modern steam turbines? (I dont know, I am asking). The claim that they are "essential" is also false, (building a generator with soft-iron electromagnet is something done at high school) but I am sure they improve cost/MW.

    PS. I note that Enercon are already building wind turbines with only electromagnet - see here. Note that tech works for turbines from 350kW all the way to 7.5MW which must be among the world's largest.

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  38. Mancan, do we need to go to zero emissions? My understanding is that we need to dramatically reduce emissions, but if the West (responsible for most of the excess CO2 in the atmosphere) drops to zero, then the developing countries can use more FF and make the transition later. What is certain is that sooner or later the whole planet must transition from FF since they are a finite resource.

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  39. Mancan18,

    Jacobson account for increased demand in the USA in this paper.  Total power use is lowered because electric motors are much more efficient than internal combustion engines.  In the supplementary material and online here they describe how all nations in the world can convert to 100% renewable energy by 2050 including increased demand by 2050.

    The remainder of your post seems to be your personal opinion.  Can you link some peer reviewed material to support your ideas?  I think if you read the article summarized here you will find that they address many of your concerns and show how they can be solved.  This short summary has necessarily left out a lot of the details.

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  40. scaddenp @38 michael sweet @39

    I do not disagree with you. I think it is desireable to move to renewables and stop using FF. I also believe that FF are not going to bring developing nations out of poverty, like the latest piece of spin from proponents of FF. The reason that FF are not a solution to world poverty have been well articulated in a more recent SkS article.  Also, it doesn't pass the commonsense test. Building power grids and coal fired power stations in developing nations is not likely to be less exepensive than self-sufficient community based WWS simply because many of the people still live in villages. It would not be practical to run the power grid to them all.

    Yes, I have expressed a personal opinion. But that opinion has been moulded by reading about the whole CO2 emissions and global warming issue in science magazines like Scientific American since the mid-1970s. The first time I read about rising CO2, the CO2 component of the Earth's atmosphere was 325 ppm, and the planet had half the number of people on it than it has now. All I have seen since then, is the slow and steady rise of CO2 to what it is today. So I am sorry that I didn't provide links to support my opinion, because it is an opinion formed over 40 years through reading a wide range of literature from astronomy, physics, mathematics, world history and economics. I use SkS to keep up to date with the latest findings.

    What I am concerned about is the total disconnect between the realities of the current economic situation and the necessity of reducing emissions. I think that we are 18 years too late. The world should have taken serious action after Kyoto, because if we had, we would now be 18 years further ahead with the technology. Unfortunately Kyoto failed and there wasn't a clear message given to the FF companies about the long term viability of FF technology, after all FF companies comprise over half the top 10 of the wealthiest companies in the world. Changing from FF will be a huge loss for their investors who are some of the wealthiest people on the planet. It is still the case with the people who matter, those with the money to do something serious about global warming, is that short term profits still trump long term disadvantage. I hope that Paris will be a success. But that is not guaranteed. If this were the 1980s with Thatcher and Reagan in power at the height of the Cold War, it would be a success, because they were leaders who listened to their scientists, and when scientists articulated the CFC problem and the ozone layer, they listened. An international agreement to reduce CFCs was made by a disparate group of political entities, from arch conservatives to leaders of communitst nations. As a result, the level of CFCs reduced in the atmosphere and the ozone layer gradually repaired itself. The same sort of action is needed on CO2 today, with the developed world moving to zero emissions while developing the new technologies that the developing world will need. This article shows that zero emissions can be achieved. Sadly, I don't think that current leaders have the political wherewithall to make it happen.

    Sorry for the epistle.

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  41. Political wherewithall can never be there to the extreme degree you ask it to be. People make money in this world and it's called enterprise.

     The truth to the solution of this complex conundrum may lie in the fact that cogeneration makes complete loss of fossil fuel use absurd, for example.

     ...and I'm no science fiction writer!!

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  42. Hydrogen fuel cells for airliners were found to be impractical over forty years ago. The claim that Boeing and Airbus are researching that possibility needs a refernce. A session at a recent AIAA conference was devoted to research on using battery power for airliners without comment on the posssibility of obtaining material for the lithium ion batteries for long.

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  43. Airbus research hydrogen fuel cells. press release sept 2014

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  44. denisaf @42.

    If anybody needs to present "a reference" then that is yourself. You make bold claims here but without a single shred of evidence to back up your foolhardy assertions. So who were these "reputable researchers" you mentioned @25, the ones who have "thrown out over forty years ago ... the suggestion that airliners could be powered by hydrogen" and presumably the same ones who found, as you asserted @42, "hydrogen fuel cells for airliners ... to be impractical over forty years ago." All this with not a whiff of a reference.

    Airbus were a big part of the Cryoplane project that, much more recently than 1975, concluded it was technically feasible to power air transport with hydrogen fuel cells except that the supply hydrogen wasn't available. And given that finding, we should not be so surprised to see Beoing continuing with their own researches.

    And denisaf, if you want to have a bish-bash-bosh over a session at an AIAA conference, do pause a while. The AIAA hold many events that could be described as 'conference' and so this session you refer to will not be evident to someone reading your words. Thus without a reference to it you will appear as just another know-it-all mouthing off on the internet.

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  45. scaddenp, to be honest I've barely scratched the surface in understanding the dymanics of rare earth metals in the construction of things like gearless wind turbines and thin solar panels.  I figured that by bringing my concerns to Skeptical Science I'd gain futher insights to what was only recently pointed out to me as a problem.  You've enlightend me on the fact that thin solar pannels are used less often than normal PV instalations which don't use rare earth metals.  

    Concerning wind turbans, what little bit I've learned is that the reason they've gone to rare earth mineals was to make the wind turbines gearless which means they have far fewer mechanical problems which had plagued them in the past.

    I noticed the link you posted was 4 years old.  That seems like a long time in todays high tech world.  Do you know if the turbines built by Enercon have panned out well since 2011?  

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  46. Stranger - Rare earth magnets are among the most powerful permanent magnets, making very efficient windmills cheaper and more effective. As such, their availibility is a potential limiting factor in wind energy. 

    However, in addition to the current supplies from China, there are mines being developed in Austrailia, Brazil, Canada, and Vietnam that may be online in a few years, and there are potential replacements in the works such as iron nitride magnets with no rare earth components and twice the magnetic energy of present rare earth magnets. 

    Rare earth availability doesn't represent a ceiling on potential wind energy. 

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  47. johnkg, the article you reference discusses research to replace airliners' auxiliary power units (APUs) by hydrogen fuel cells. APUs are used to generate power for the aircraft needs when parked on the ground with the engines shut off. APUs are small gas turbines but pack a lot of power and have even been used occasionally as a powerplant for smaller aircrafts. However, it is a far cry from powering an ariliner for flight with hydrogen fuel cells, and the article does not mention any intention or researching in that direction. 

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  48. MA Rodger, your link to the Boeing fuel cell demonstrator leads to a paywall. The cryoplane assessment project was an entirely theoretical study that concluded that using hydrogen as fuel for transport aircraft was technically feasible. However the extra weight leads to hiher operating costs. Furthermore, it has, to my knowledge, not led to the development of any flying prototype. It also did not seem to consider all the infrastructure and operating procedures modifications, which would be significant.

    There may be more medium term future for aviation in generalizing jet fuel from algae, which has a chance to be carbon neutral if processes use renewable energy or their own product. This would have the inconvenient of not alleviating the release of turbine exhaust gases at high altitude but at least would prevent further injection of previously stored carbon. These fuels are also easier to deal with when spilled.

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  49. It's worth noting that there is a large ARPA-E project to develop permanent magnets that are free of rare earth elements called Rare Earth Alternatives in Critical Technologies (REACT). 

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  50. Thanks KR.  That's really  informaive stuff.

    I've make it here everyday since this website was created but rarely post.  Real Climate use to be my main read but I've found SS to be more helpful for the non science majors.


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