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A small electric plane demonstrates promise, obstacles of climate-friendly air travel

Posted on 21 October 2019 by Guest Author

This is a re-post from Yale Climate Connections by Lindsay Fendt

When the pilot guides the electric airplane from its hangar, there is only a light whirring of propellers instead of the roar of an engine. And it leaves no exhaust in its wake as it takes off from a small air strip south of Denver. The small plane, the eFlyer, is the first all-electric plane to seek FAA certification and its builders hope it will revolutionize the aviation industry as the first commercial electric airplane.

“Electric motors are not new,” said George Bye, President of Bye Aerospace and the airplane’s creator. “But the application to airplanes is remarkable, and until recently most people thought it was impossible.”

Bye, who started working to develop the plane 12 years ago, said it took a transformation in battery and engine technology to make the eFlyer possible. While cars have long been able to carry heavy batteries and engines, airplanes must be aerodynamic and light. Bye completed his design once batteries and electric engines became small enough. The eFlyer is the first all-electric airplane to enter an FAA certification program, and the first eFlyers could take to the skies as early as 2021.

Training pilots, draining carbon

Bye initially designed the electric plane after learning of a growing commercial airline pilot shortage. He thought the eFlyer could cut down on expensive fuel costs for flight school training. But in addition to breaking down barriers to entry for new pilots, electric planes could one day make the aviation industry much friendlier to the environment.

Electric airplanes ‘not only possible, but it’s revolutionary.’ – Bye Aerospace creator

Personal cars drive the conversation about transportation’s impact on climate change, but some estimate that an airplane flight could be 50 times worse for the climate than a car driven the same distance. Airplanes, like cars, release carbon dioxide, but each flight also releases nitrogen oxides, water vapor and particulates that can contribute to global warming. When released at high altitude these other emissions usually amount to more than half of a plane trip’s contribution to climate change.

Despite the environmental impacts of aviation, the industry has been largely left out of the conversation about electric vehicles, primarily because of technological limitations. The FAA would not even consider electric airplanes for airworthiness until 2017. The eFlyer, though only a small plane for flight training, could start to change that conversation.

“We are showing that this is not only possible, but it’s revolutionary,” said Bye.

Big savings for flight schools

For flight schools the cost savings are big. Using Colorado prices, it takes about $3 worth of electricity for the eFlyer to make a flight that would require $50 worth of fuel. For commercial airline pilot training, that adds up to more than $70,000 in savings. If the plane is charged with renewable energy, it also cuts greenhouse gas emissions to zero.

While Bye Aerospace is on schedule to be the first plane with FAA approval, other companies are also starting to make electric airplanes. Two battery-powered nine-seater concept planes – one all-electric and another hybrid – made appearances at this year’s Paris Airshow. The commercial aviation industry has started to grapple with its large contributions to climate change by forming CORSIA, a carbon offsetting scheme that promises only carbon-neutral growth in the industry after 2020.

Still, both the technology and the aviation market are a long way from scaling-up to large electric jets. The four-seat eFlyer has a maximum fly time of only four hours, and batteries and electric engines get more expensive and heavier as they are scaled up. Though demand for green tech in aviation is expected to rise, according to Swiss investment bank UBS, mainstream airlines have resisted reforms, like taxation, that could fund a faster transition. Aviation has also been slow to adopt alternative fuels like hydrogen, pointing to high costs and a lack of regulation.

Norway moving ahead on electric airplanes

As other companies start to catch on to the potential of electric planes, Bye Aerospace already has 604 entities that have expressed interest in the eFlyer either with a deposit, a purchase commitment, or an option. The Norway-based flight school OFM has a purchase deposit on 60 planes and intends to charge the planes on the country’s electricity grid that is powered almost entirely with renewables. Norway already has more electric cars than it does gas-powered cars and appears eager to extend that infrastructure to electric airplanes.

While most of the eFlyer’s customers have been flight schools, Bye says the four-seat model of the eFlyer could be used for other things. The quiet plane would be ideal for flying low over dense urban areas without disrupting residents, he says. The lack of noise, combined with low cost and a low environmental footprint, mean that the eFlyer could one day be used for on-demand charter flights or courier services.

“We are innovating with a purpose,” Bye said. “We are very happy to have an environmentally and technically interesting aircraft that also has a compelling benefit to the cost of flight.”

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Comments 1 to 28:

  1. Israel's Eviation is apparently on track to bring their 9 seat regional airline offering to market ~2022, with a schedule for certification complete in 2021.  They have a NE US regional commuter airline on tap as a launch customer. Slated performance is 600NM,  240kt.

    Small detail is that as of last month Eviation needed about $200 million to complete the program but they seem confident. Most of the mystery is wrung out already, including motors, batteries, successful assembly of first test article.

    The market for such aircraft apparently encompasses some 45% of air routes (we fly not far enough too much?)

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  2. Alice looks indeed like a great airplane. Incidentally led me to discover Phinergy, because there was some possibility that Alice's batteries be provided by Phinergy. Looks like an interesting technology:


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  3. @All, Please see specifics concerning my problems with the Fourth NCA report. (Moderator - Was I locked out for the last 24 hours?)

    0 0
    Moderator Response:

    [DB]  You were not locked out from making comments in this venue.

  4. Summary:

    I asserted that climate science often ignores the experts. This happens when the experts in economics (and other social sciences) are ignored in favor of non-experts, particularly climate scientists.

    Other commentators on this site strongly opposed my view.

    I used the example of the economic loss estimates of climate change in the Fourth NCA report. I showed that only 1 in 8 referenced researchers in fact had training and experience in economics (or even public health).

    I also pointed out that the work of a recent Nobel Laureate in economics who had worked in exactly this area was ignored in the NCA report. Similarly, the work of other less prominent economists in this area was ignored.

    The commentators who opposed my view have been unable to provide the names of any participating economists to refute my argument.


    Check and Checkmate

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    Moderator Response:

    [DB] Sloganeering and empty rhetoric snipped.

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

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit  intentionally misleading comments or simply make things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    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, as no further warnings shall be given.

  5. Where are the economists (and health experts)?

    I cannot answer all the scurrilous charges leveled at me at once (ha-ha, just kidding), so I will take a piecemeal approach to keep the discussion manageable.

    This comment concerns my contention that economists are severely under-represented in making estimates of economic losses. (As you will see, public health experts are also conspicuously absent.)

    Start by going to p. 551 of the Fourth NCA report Vol. II. This section concerns the increased mortality due to higher temperatures. In case there is any question concerning the importance of this section, Hsiang et al 2017, Fig 5., shows that premature mortality constitutes about 75% of the economic costs of climate change. So, this section is extremely important. (Hsiang, who has no educational or professional training in economics, is mentioned 33 times in the NCA report.)

    The following are the economic “experts” cited directly in this section. Surprisingly, most are also not even trained in public health. How can you estimate the economic loss of premature death with no credentials in economics or in public health????

    (from references 161, 162, & 168 for section 14 of Vol II):

    These are my Preliminary findings - please correct me if I’ve made any errors:

    K.W. Oleson (NO apparent professional or educational training in economics, or public health)

    G.B. Anderson (NO apparent professional or educational training in economics)

    Benjamin Jones (yes, an economist)

    Seth A. McGinnis (NO apparent professional or educational training in economics, or public health)

    Benjamin Sanderson (NO apparent professional or educational training in economics, or public health)

    Claudia Tebaldi (NO apparent professional or educational training in economics, or public health)

    Brian C. O’Neill (NO apparent professional or educational training in economics or public health)

    J. Gao (NO apparent professional or educational training in economics, or public health)

    So only 1 in 8 “experts” on estimating the biggest part of the economic impact of climate change is an economist. So, why are the economists (and public health experts) missing in action?

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    Moderator Response:

    [DB] Inflammatory and baiting rhetoric snipped.  

    Please clean up your game.

  6. Can we move this to the appropriate thread? This one is about electric aviation.

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  7. markpittsusa @20

    Unfortunately your comments appear deeply flawed.

    You say "This comment concerns my contention that economists are severely under-represented in making estimates of economic losses. ....Start by going to p. 551 of the Fourth NCA report Vol. II. This section concerns the increased mortality due to higher temperatures. In case there is any question concerning the importance of this section, Hsiang et al 2017, Fig 5., shows that premature mortality constitutes about 75% of the economic costs of climate change. So, this section is extremely important. (Hsiang, who has no educational or professional training in economics, is mentioned 33 times in the NCA report.)....The following are the economic “experts” cited directly in this section. Surprisingly, most are also not even trained in public health. How can you estimate the economic loss of premature death with no credentials in economics or in public health????... (list of people)"

    Incorrect. You have only listed a few of the people involved in the section on heatwaves and related matters. Your references in this section are namely 161, 162 ,168 and they relate to a preliminary paragraph that only discusses the physical science as follows: "The projected increase in the annual number of heat wave days is substantially reduced under a lower scenario (RCP4.5) compared to a higher scenario (RCP8.5), reducing heat wave intensities161,168 and resulting in fewer high-mortality heat waves162,168 without considering adaptation ".

    You have ignored the rest of the relevant sections on the economics of the heatwave issue that starts "Labor Productivity Under a higher scenario (RCP8.5), almost two billion labor hours are projected to be lost annually by 2090 ..." and numerous references in these paragraphs including 157, 160, 167, 169 and others. A quick scan of the bibliography indicates these include economics research institutes and the like. 

    S Hsiang is not an economist , however the other contributors to his paper include economics expertise and other experise  as follows:

    Solomon Hsiang1,2,*,†, Robert Kopp3,*,†, Amir Jina4,†, James Rising1,5,†, Michael Delgado6, Shashank Mohan6, D. J. Rasmussen7, Robert Muir-Wood8, Paul Wilson8, Michael Oppenheimer7,9, Kate Larsen6, Trevor Houser6

    1Global Policy Laboratory, Goldman School of Public Policy, University of California, Berkeley, CA, USA.

    2National Bureau of Economic Research, Cambridge, MA, USA.

    4Department of Economics and Harris School of Public Policy, University of Chicago, Chicago, IL, USA.

    5Energy Resource Group, University of California, Berkeley, CA, USA.
    6Rhodium Group, New York, NY, USA.

    7Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ, USA.

    8Risk Management Solutions, Newark, CA, USA.



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  8. Move my comment to a relevant thread if you want.

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  9. When I say Hsiang is not an economist, I mean he has no formal training in economics, has never been part of an economics faculty, and has never published in a peer-reviewed economics journal.

    That is exactly the problem.  He is a climate guy trying to do economics.

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  10. As I carefully explained, my analysis only concerned mortality since that is 75% of the economic costs.  

    (In the past I've looked at the other sections you mention, but the result is about the same.)

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  11. @Nigel.

    I have provide detailed analysis that I (and I think most economists) would agree shows that only 1 in 8 directedly cited "experts" for mortality related economic costs are not trained in economics or public health.

    You believe I am wrong. Please share the names of the economists that you think contributed. 

    The entire burden of proof is not mine alone.

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    Moderator Response:

    [PS] This is offtopic. Please place followups here.

    Start by explaining whether you agree with Hsiang 2017 et al.

    Backlink to this comment would help.

    Further offtopic comments by anyone will be deleted.

  12. I have placed a response on the followup link.

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    Economists Estimating Economic Costs of Climate Change Due to Labor Lost (16%)

    This post is part of my on-going response to several commentators who asked me to be more specific about the source of my views.

    My last post concerned the under-representation (only 12-1/2%) of professional economists participating in estimating the economic loss of climate change as it related to premature Mortality (75% of the total economic cost according to Hsiang et al 2017) in the Fourth NCA report.

    This comment concerns the lack of professional economists participating in the Labor Loss part of economic losses in that same report.

    The list below shows that only 3 of 19 experts (about 16%) of those estimating economic costs actually have educational or professional training in economics.

    [Definitional Note: Here “educational training in economics” means a graduate degree in economics. “Professional training in economics” means held a professional position as an economist, per se, on a economics faculty, in government, or in business.]

    Go to p.552 of the Fourth NCA report Vol. II. The references concerning the economic cost of labor lost due to climate change are 157, 167, 169, 164, 170, and 160.

    The experts cited directly (as opposed to citied indirectly through another report) are below.

    My Preliminary findings:

    Ref #157 references another report.

    Ref. #167

    Salomon Hsiang (NO apparent professional or educational training in economics)

    Robert Kopp (NO apparent professional or educational training in economics)

    Amir Jina (Yes, an economist, or at least can publish as such)

    James Rising (NO apparent professional or educational training in economics)

    Maria Del Mar Delgado (NO apparent professional or educational training in economics)

    Shashank Mohan (NO apparent professional or educational training in economics)

    D.J. Rasmussen (NO apparent professional or educational training in economics)

    Robert Muir-Wood (NO apparent professional or educational training in economics)

    Paul Wilson (NO apparent professional or educational training in economics)

    Michael Oppenheimer (NO apparent professional or educational training in economics)

    Kate Larsen (NO apparent professional or educational training in economics)

    T. Houser (NO apparent professional or educational training in economics - but not 100% clear from what I can find.)

    Ref #169

    Joshua S. Graff Zivin (YES, an economist)

    Matthew J. Neidell (Yes, an economist)

    Ref #164

    Michael D. Mastrandrea (No apparent professional or educational training in economics)

    Ref #170

    J. P. Dunne (No apparent professional or educational training in economics)

    R. J. Stouffer (No apparent professional or educational training in economics)

    Jasmin G. John (No apparent professional or educational training in economics)


    K. Gordon (No apparent professional or educational training in economics)

    In my view, as long as economists are not the primary experts making estimates of economic costs, critics are justified in questioning whether these are really experts.

    I’d appreciate any comments or corrections.

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  14. markpittsusa @13, did you not read the simple, clear instruction in the blue box @11 to post your off topic comments on the alternative link (last weeks research thread)?

    I will post a response on that link. In summary I have no problem with 3 professional economists out of 19 experts.  Please provide evidence it is inappropriate.

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  15. I guess that one day it's conceivable that large electrically powered aircraft could be in the air, but at present basic power/weight ratios mean that only small and short range ones are possible.

    By promoting very small commuter-style aircraft we are effectively encouraging more wealthy individuals to get airborne, not encouraging mass transport to clean up!

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  16. The potential fuel/cost saving for pilot training sounds comical in light of the thousands of tonnes of CO2 each pilot thus trained will enable airlines to dump into the atmosphere during the course of his or her career.

    If the airline industry needs more pilots, we're already too late to prevent climate apocalypse. The airline industry should be well along in the process of phasing itself out by now, if we wanted to have any chance of staying within even a risky carbon budget.

    Each new airliner that enters service has a projected lifetime of 40 years. There are no zero-emission airliners even on the drawing board yet. The marginal improvements in airliner efficiency have been more than offset by the growth in flying.

    Humans simply lack the grasp of morality and facts necessary to avoid cooking themselves off the planet. Flying is proof of this.

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  17. To quote Monty Python "and now for something completely different" This Gigantic Chinese Airship Flies on Solar Power For Up to Six Months at a Time.

    Daniel Mocsny - I get your scepticism on this,  and zero carbon air travel will be challenging and the first generation planes will be far from zero carbon. But remember those first mobile phones like bricks with limited coverage and abilities? Things changed faster than I would ever have thought possible.

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  18. I don't totally agree with Daniel. Transportation accounts for 29% of all CO2 emissions, air transport represents 9% of that. In comparison, electricity and industry total 50%. There are low hanging fruits in reducing emissions far easier to reach than high flying planes (no pun intended).

    If we could eradicate coal burning for electricity and drastically reduce gasoline burning for ground transportation, we would see a halt in the increase of CO2 in the atmosphere even with continued air transport at the volume where it is now. Solutions have to be realistic. Air transport presents the greatest engineering challenge because of the energy density of jet fuel. At least some manufacturers are working on possible solutions and are not showing denial or some illusion that things can go on the same they have been for the past 50 years.

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  19. Philippe @18,

    I generally agree with acting faster on the larger impacting parts of the developed global activity.

    However, the more important point is that Air Travel is not a requirement for the future of humanity. Sure, it is Nice for those who get to enjoy it. But only a small portion of current Air Travel is "Necessary for sustainable global decent living", mainly for emergency aid situations.

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  20. It'll be interesting to see how the split between short and long haul aircraft develops. 

    I've been repeatedly surprised by battery technology development but it seems as though achieving battery energy density required for long haul flight is still very challenging, requiring another order of magnitude performance improvement in density let alone the economics issue of how many flight cycles such batteries could support before they degraded.

    Some kind of nudge to accelerate biofuels (algae is looking promising) would be helpful. Boeing and others have invested some substantial resources in establishing underpinnings for this but only as a long term project, looking far ahead. There's progress on the shelf there and more work to be done, quickly or leisurely. Quickly would be better.

    Meanwhile, we could think harder before flying. Before making reservations, do some method acting and imagine being herded like an animal. That's what you're buying with your ticket. :-)

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  21. doug_bostrom@20,

    Hydrogen fuel cells may be a practical option for air travel. Time will tell.

    I agree with seriously considering the reasons for taking a flight until a decent way to fly is developed. I am not a believer in buying off-set credits to justify an 'optional' flight.

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  22. Good points from contributors. There can be progress nonetheless

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  23. Yeah liquid hydrogen might work. I don't think we'll be able to engineer pressurized storage on the scale/weight points needed (monolithic containers are too heavy, fatigue cycle life of composite containers is quite poor and we're speaking of tens of thousands of cycles).

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  24. Hydrogen fuel cells for aircraft would face safety challenges. Even if these were overcome the public might still feel insecure and not supportive. It's like the public fear of nuclear power, which may be excessive, but is very real and has killed the nuclear industry dead in some places.

    However I think some combination of biofuels, electric aircraft where possible, less flying and carbon offsets would certainly work. The combination would get us to net zero. Biofuels blends up to 50% are acceptable, leaving the balance to be achieved by less flying, carbon offsets, etc which looks realistic although it looks like it  would commit a very large part of new forests to these offsets.

    The challenge is this is a lot of different components to get into in place and coordinate, especially in a free market democracy. China could do this by dictate, but this is not possible in a free market democracy. So would it make sense for western countries to go on a war footing and give government's sweeping powers? I would not be loving this, and it seems unlikely. But who knows....

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  25. nigelj@24,

    Free Market activity fundamentally develops powerful resistance to any attempt to limit activity in the competitions for Status, especially when the limitations would reduce some developed perceptions of status relative to others (winners do not like changes that reduce their winning - even if they understandably deserve to lose status - even if the changes will only make them less obvious winners).

    However, limitations imposed to achieve and improve on safety levels are 'adapted to' after attempts to block them from being developed and implemented fail (though some people still try to claim that not wearing a seat-belt and being in a car without airbag systems is 'Safer' - which only proves that what people believe cannot be allowed to govern what limitations are imposed).

    The same can be seen to be the case for limitations to achieve and improve on the constantly improving understanding of the Sustainable Development Goals (social and environmental safety). The Free Market can adapt to SDG limitations. But its participants can be expected to powerfully resist the development and implementation of such limitations.

    Air Travel regulations to correct what has developed probably need to be implemented with the understanding that the developed magnitude of the activity needs to be reduced. That reduction of a portion of the economy will be powerfully resisted no matter how harmful and unnecessary the developed activity is actually understood to be. A similar resistance to correction can be seen in places like Alberta where the development since the need to reduce global fossil fuel was solidly established has been attempts to increase the rate of benefiting from the export of fossil fuel resources (the USA also did it, as well as Australia).

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  26. I keep thinking there should be an attempt to create a rocket assist system to enable electric aircraft to achieve greater range. Rockets can efficiently use oxygen/hydrogen mix without producing carbon emissions. 

    The initial climb to cruising altitude is the phase of flight that requires the most energy. If you could build a carrier system similar to what Scaled Composites used to put their small manned craft into space, perhaps that—as a rocket propelled carrier—could carry an electric aircraft up to a high cruise altitute from which to initiate the flight. The carrier craft would then fly back to the airport to refueled for the next flight.

    My other recent thoughts on the future of electric aviation is that, perhaps people need to get used to slower, more relaxing flights for long trips. If you could create an electric aircraft design that could make a transoceanic flight with an assist to cruise, slower flights might be what make that feasible. The economics of electric flight hold such a large advantage that it may be cost effective to give customers business-class style cabins and expect normal 12 hr flights to last 20 hrs instead. The additional 8 hrs could be very tolerable in a comfortable setting.

    Additional note: electric motors offer some clear advantages over fuel-based engines since both ICE and turnbines require air for combustion. At higher altitudes a great deal of additional energy is used to accelerate air into a chamber for combustion. There are efficiency losses for electric motors as well, but I believe it's limited to accelerating air for propulsion rather than propulsion and combustion.

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  27. Wait a minute. Both hydrogen fuel cells and hydrogen powered rockets produce water vapour which is a greenhouse gas. This would put water vapour reasonably high up in the atmosphere. I assume this has been evaluated hasn't it? But has it?


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  28. Further to Rob's remarks, as I read it the objective of hybrid aircraft is to employ batteries and electric assist to reduce fuel guzzling during take-off and a portion of ascent. 

    JATO: particulate emissions from aviation boost rockets as an elliptical geoengineering scheme? Hmm. Maybe we'd best remain silent on this. :-)

    Leisurely aviation: go to, plug in "dirigible" and "airship" as search terms, sort results in ascending order and one sees a picture of a world that did not happen, with airships occupying the top slot in commercial aviation. However it wasn't so much problems with lifting gas that truncated this path as issues with control of the vehicles in inclement weather, particularly during docking and while at dock. 

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