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Comments 27651 to 27700:

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

    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.

  2. Permafrost feedback update 2015: is it good or bad news?

    First post from this non-scientist Andy - re. the recent Princeton paper -

    "New research led by Princeton University researchers and published in The ISME Journal in August suggests that, thanks to methane-hungry bacteria, the majority of Arctic soil might actually be able to absorb methane from the atmosphere rather than release it. Furthermore, that ability seems to become greater as temperatures rise." 

    This has been hailed in some quarters as the end of the "methane scare", because "the bugs will eat it all".

    The paper refers to "Arctic soils containing low carbon content — which make up 87 percent of the soil in permafrost regions globally". I suspect that the positive feedback from the other 13% of soil with higher carbon content may be greater than the negative feedback observed by this study, but what do I know?

    I have yet to see any feedback from scientists which supports my view, and meanwhile this paper is being used, and possibly abused, by the usual suspects.

    I would be grateful for your views.

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

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

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

    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.

  5. PhilippeChantreau at 11:53 AM on 25 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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.

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

    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.

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

    @ 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.

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

    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.

  9. World Bank rejects energy industry notion that coal can cure poverty

    The arguments for renewable energy for developing countries are valid, but the cost factors must be considered. A carbon tax could go a long way balnce the cost difference. Another factor is compensating developing nations for using the more expensive option of renewables.

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

    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.

  11. Adapting to air pollution with clean air stands in China

    I am searching for words far beyond "despair".
    Is this what homo sapiens calls a "solution"?
    The situation must be way out of any control.

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

    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.

  13. Adapting to air pollution with clean air stands in China

    Based on the reports of the pollution composition and level in China prior to the Olympics, I doubt that these shelters reduce pollutant levels to the US standard for Particulate, SO2, NOx, Ozone and Lead. At 70% reduction it would be marginal. However, the technology to reduce all of these pollutants would require three different technologies. Particulate (and Lead) would likely be the easiest by using a fabric filter. By adding an alkaline material to coat the inside of the fabric filter, the SO2 might be reduced. At great expense a paladium catalyst may address the NOx and Ozone. However, I would have to see a substantial amount of data to beleve any high reduction in the pollutant concentrations. That still does not address the hazardous organic vapors (benzene, toluene, etc.) which would require the addition of activated charcoal for removal.

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

    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. 

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

    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. 

  16. Medieval Warm Period was warmer

    Steven Sullivan @233.

    The 2012 comment by realscience @148 referred to Oppo, DW, Y Rosenthal, BK Linsley, 2000-year-long temperature and hydrology reconstructions from the Indo-Pacific Warm Pool, Nature, 460 1113-1116, doi:10.1038/nature08233, 2009.  You are referring to a more recent paper - Rosenthal, Y., BK Linsley, Oppo, DW, Pacific Ocean Heat Content during the past 10,000 years, Science, 342 617-621, 2013.

    The quote you make from this later paper has been bandied about by contrarians, mainly because they rather enjoyed the paper saying "The inferred similarity in temperature anomalies at both hemispheres is consistent with recent evidence from Antarctica (30), thereby supporting the idea that the Holocene Thermal Maximum, MWP, and LIA were global events," but felt the sentence you quoted needed a bit of trashing as it spoiled their interpretation of what the paper was saying. So some branded your quote "a single sentence of genuflection to CAGW."  Reading this contrarian blather, I think it's fair to say that the contrarians inabilities in understanding 'CAGW' are also persent in their understanding of the relationship between OHC & surface temperatures.

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

    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.

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

    No problem. Honest mistake.

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

    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.  

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

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

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

    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.

     

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

    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). 

  23. PhilippeChantreau at 02:50 AM on 25 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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.

  24. PhilippeChantreau at 02:27 AM on 25 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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. 

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

    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. 

  26. Steven Sullivan at 01:55 AM on 25 August 2015
    Medieval Warm Period was warmer

    realiscience wrote (in 2012): "Did you look at Oppo's data points. Some are clearly at this level, meaning that it is within the margin of error that sea surface temperatures could have been higher. ?"

     

    I read the paper.  Did you see this part? " The modern rate of Pacific OHC change is, however, the highest in the past 10,000 years (Fig. 4 and table S3)."    OHC = ocean heat content

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

    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?  

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

    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.

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

    Airbus research hydrogen fuel cells. press release sept 2014

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

    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.

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

    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!!

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

    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.

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

    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.

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

    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.

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

    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.

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

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

    Solar panels need tellurium

    http://blogs.ei.columbia.edu/2012/09/19/rare-earth-metals-will-we-have-enough/

    Moderator Response:

    [JH] Link activated. 

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

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

    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.

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

    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...

  39. PhilippeChantreau at 23:22 PM on 22 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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.

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

    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.

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

    @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.

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

    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.

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

    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.

  44. One Planet Only Forever at 15:01 PM on 22 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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?

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

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

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

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

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

    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.

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

    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.

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

    @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.

  50. PhilippeChantreau at 07:02 AM on 22 August 2015
    New paper shows that renewables can supply 100% of all energy (not just electricity)

    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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