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What is the real cost of green hydrogen?

November 28, 2020

By Paul Homewood


h/t Dennis Ambler



There’s an informative, but also rather garbled, article in Euractiv concerning the cost of hydrogen



Green hydrogen is much in the news. In October Cap Gemini published a report called “Net Zero 2020”. Page 36 had a section on green hydrogen with the declaration “At around €6 per kg, green hydrogen is not competitive today with fossil energies (parity at €1/kg equivalent to €25/MWh)”.

Last week another hydrogen organisation announced itself “the Renewable Hydrogen Coalition” accompanied by (yet another) report on green hydrogen which contained (yet another) price estimate for green hydrogen – €6/kg.

Absent from the above is any explanation as to how these price were derived, a common feature of reports and blogs on the subject.

The EU and green hydrogen

Given recent European Commission publications (e.g. Hydrogen Strategy) and declarations by various EU Member States such as Germany, green hydrogen now has a prominence which contrasts with its position at the start of the year.

However, the starting point for green hydrogen policy development in the EU and Member States has to be a good understanding of how current green hydrogen prices are formed, where they currently stand and their likely future trajectory. What follows  provides a true and clear view of green hydrogen price formation with current and future price developments.

Green hydrogen price formation

Green hydrogen is produced by electrolysers that use renewable electricity and water to produce hydrogen and oxygen. There are two main cost elements, capital costs (capex) for the electrolyser installation and operation (and maintenance) costs (opex).

By far the largest operational cost (circa 95%) is the cost of electricity. Electrolyser manufacturers estimate the capex/opex split at roughly 20/80 (at a utilisation rate of 40% of full load over a year). This means that 80% of costs are attributable to opex and thus electricity and 20% to capex.

The other important metric for determining green hydrogen price formation is the amount of electricity needed to convert water into hydrogen. The most commonly used figure is between 55kWh and 60kWh of electricity per kg of hydrogen production. The industry expects this to fall to around 50kWh by 2025/2030 due to technology improvements.

Public presentations by companies such as Hydrogenics and conversations with other electrolyser manufacturers confirm that the assumptions and approaches in the two preceding paragraphs are realistic and valid.

Green hydrogen production using industrial electricity prices

The table shows green hydrogen price estimates by three different organisations. Using information about green hydrogen price formation, it is possible to re-construct the electricity price on which the green hydrogen price was based. The numbers obtained suggest that industrial electricity prices (see Eurostat) were used as a basis for the green hydrogen price.

Green, grey and blue hydrogen: comparing apples and zebras

Grey and blue hydrogen are produced using natural gas which attracts almost zero taxes and levies.

By contrast green hydrogen prices have taxes and levies imposed on the feedstock (electricity) which is double/quadruple the original price of the feedstock (renewable electricity). It is neither rational nor sensible to make such a comparison between a heavily taxed product (green hydrogen) and a zero taxed product (grey or blue hydrogen).

Nevertheless, almost all commentators on the subject think that this is a valid comparison

Green hydrogen: real-world pricing

Iberdrola recently announced a project (to be completed during 2021) to build 100MW of PV and couple this to 20MW of electrolysers to produce green hydrogen that would be piped to be used at an industrial plant producing fertiliser. The cost of producing electricity from PV in Spain (or Portugal) is well understood. Conservatively, the cost is around €25/MWh. Recent projects in Portugal have been priced in the range €12 to €20/MWh.

Using the green hydrogen price formation metrics outlined previously and €25/MWh as the electricity price gives a green hydrogen price of €1.65/kg. This price is based on the assumption that the PV farm is directly coupled to the electrolysers. The approach of direct coupling between a renewable power station and electrolyser facility is becoming common.

Misleading statements

Cap Gemini’s statement “green hydrogen is not competitive today with fossil energies (parity at €1/kg equivalent to €25/MWh)” is thus both untrue and true. Given Spanish (and Portuguese) electricity prices from PV, green hydrogen produced using this electricity is cost competitive now with both blue and grey hydrogen.

However, if the electricity system is and industrial electricity prices are used then green hydrogen is hammered by taxes and levies.

Given the above, the prices for green hydrogen proposed by Cap Gemini, BNEF, the Renewable Hydrogen Coalition/Breakthrough Energy and others and the price comparisons they make are highly misleading.


They are quite right that you should not compare electricity prices which includes taxes and levies against natural gas which does not.

However they shoot themselves in the foot by using this table to prove their point:


Now correct me if I am wrong, but I know of nowhere in Europe where retail prices of electricity are as low as 90 euro/MWh. In the UK, we are looking at around £150, which equates to 166 euro.

In other words, it appears that the studies they are complaining about have already excluded taxes and levies. Indeed according to OFGEM, these account for 28%, which would bring our 166 euro down to 120 euro.



The authors of this piece go on to use a solar farm in Spain as an example to show just how cheap green hydrogen really is. However, this solar farm feeds the electrolysis plant direct, thus avoiding all sorts of network costs.

That is fine for a small, local operation feeding a fertiliser plant. But for industrial scale hydrogen, electrolysers will need access to reliable, large scale and regular power from the grid. Like it or not, they will have to pay for all of the various transmission and network costs.

The latest round of offshore wind CfDs are currently priced at about £48/MWh, so adding on network and operating costs would leave us with a price of around £100/MWh. So even the 90 euro figure is probably understated, at least as far as the UK is concerned.


Meanwhile the article also gets the cost of fossil fuels wrong:

At around €6 per kg, green hydrogen is not competitive today with fossil energies (parity at €1/kg equivalent to €25/MWh)”.

In fact, the wholesale price of natural gas is much less than 25 euro/MWh.

Even before the pandemic, gas has been trading at around 26p/therm, which equates to £9/MWh:



It is clear industrial scale green hydrogen will be hugely expensive in comparison to natural gas, and indeed steam reforming.

Little surprise then that the Committee on Climate Change concluded that the cost of electricity would have to fall to £10/MWh to be competitive with steam reforming, which is itself twice the cost of natural gas.


  1. Gamecock permalink
    November 28, 2020 3:44 pm


    The cost of green hydrogen approaches infinity.

  2. Harry Passfield permalink
    November 28, 2020 4:00 pm

    As I was reading this I had one eye watching a prob on BBC2 about ancient waterways, one of which was the Broads. There, they explained how the wetlands were drained by windmills. Without any irony, they went on to explain how mills were gradually improved by making them more efficient: they were converted in turn to diesel and then electric motors.

    If there was a true need for hydrogen you would not be using windmills as a source of electrolyser. Further more, if it wasn’t for the nonsense of carbon zero we wouldn’t have to listen to the nonsense of converting the energy of a natural gas to a manufactured gas just to do the same job – create energy – af a much higher price.

    • A C Osborn permalink
      November 28, 2020 6:40 pm

      And of less calorific value and lots of storage problems.

  3. Harry Passfield permalink
    November 28, 2020 4:01 pm

    Prob = prog

  4. Sobaken permalink
    November 28, 2020 4:31 pm

    Obviously it’s not competitive if it’s buying power from the grid at market rates. To be economical it would need some sort of reverse capacity market, where electrolysis plants have a contract that permits them to use power from the grid only when there’s an oversupply of intermittent generation, but at a greatly reduced price. Which is essentially a replacement of constraint payments, you end up still subsidising renewables for producing unwanted electricity, except now the electricity is at least used for something (making hydrogen) rather than being thrown away.

    • November 28, 2020 5:13 pm

      Sobaken, what do you mean by unwanted electricity? To my understanding, thus far ALL the electricity generated at a power plant is used “on line” right away (that is, no electricity is “thrown away”, except of course by users misusing their appliances)….

      • Sobaken permalink
        November 28, 2020 5:27 pm

        I mean electricity that could have been produced by a wind or solar installation, were there any demand for it. Sometimes demand is lower than combined generation of intermittent and baseload generators on the grid, so some of the intermittent generators have to be disconnected for a period of time. Technically, no electricity is being produced, the plants are just idling, but they are still paid as if they were producing electricity. This is currently a rare occurrence, but it is bound to become much more common as additional intermittent capacity is installed.

    • It doesn't add up... permalink
      November 28, 2020 7:21 pm

      The problem with your suggestion is that if there are no curtailment payments then the renewables need to charge higher prices for the power they do sell in order to earn a return on investment. This becomes no trivial matter, as the effective marginal utilisation of adding another wind farm gets less and less the more total capacity you have. We are only just beginning to see curtailment build up, but with 24GW now installed it can generate more than the grid can absorb, even if there are times when the output is derisory as in recent days. So in order to generate “surplus” power you have to invest in the capacity to produce it – that s not “free”. The only issue is who pays, which is Jack Soap. Regulators can continue to rig markets – and that is what is currently planned. See my post below.

      • Sobaken permalink
        November 29, 2020 11:04 am

        There are still payments, they are just structured differently, electrolysers get subsidised to purchase excess power from the grid at reduced price, while the wind still gets paid the usual rate for supplying power to the grid if their power is used for electrolysis. It’s not any more “free” than what there is today, and the expenses will only increase the more capacity there is, and that of course makes sense since wind is way too expensive to survive selling power at market prices. But the principal goal seems to be to make it look cheap, so avoiding overbuild of capacity and directing additional subsidies to hydrogen rather than constraint payments seemed like a clever idea to do so, while also propping up hydrogen production.

      • It doesn't add up... permalink
        November 30, 2020 7:19 pm

        The total revenue must be the same for the wind farm to cover its costs. If you charge less to electrolysers you must charge more to direct customers. If you charge for constrained off generation, that charge goes to customers anyway via grid balancing charges, so they end up paying for it : if there is no compensation for being constrained off, then prices must rise for power that is used.

        If a wind farm gets a CFD, then it is paid the same price for everything it generates, regardless of the market price. Differences are once again loaded onto customer bills, so the real picture is that you should look at the high cost CFD price as the input price to electrolysis.

      • MikeHig permalink
        December 3, 2020 6:40 pm

        That total installed capacity of 24 GW has only ever achieved a maximum output of about 14 GW, according to Mr Google.
        Eyeballing Gridwatch’s chart of the past year, wind does not get above 10 GW for much of the time.
        I’m guessing that the curtailments are nearly always due to lack of transmission capacity rather than a genuine excess over demand?

      • It doesn't add up... permalink
        December 3, 2020 7:17 pm

        Not correct. The 14GW figure only relates to live metered wind farms, which are now about 19GW of the total. In any case it is out of date. See at least this

        We have now reached the point at which curtailment is motivated by grid stability concerns. The August 9th blackout arose because of insufficient inertia on the grid and loss of large amounts of embedded generation when it became unstable enough to trigger their protection settings. Since then the Grid have been more cautious about pursuing renewables records

    • November 29, 2020 8:54 am


      constrained generation is quite small and even with expansion will be small. It is also erratic so is unsuited to commercial generation of hydrogen, or anything else that I can think of?

      • Sobaken permalink
        November 29, 2020 11:37 am

        If an additional 40 GW of wind farms is built as proposed, and demand is kept the same, curtailment of renewables could rise quite dramatically from close to zero up to about 30%. With an increase in demand from say 30 million EVs and 1/4 of heating electrified by heat pumps, this should go down to “only” 8%. Adding 5 GW of electrolysers working at 20% capacity factor (the costs of equipment and the electricity it uses would be roughly equal under such utilization) would reduce curtailment further to 4%, using up 8.5 TWh of electricity to produce 5 TWh of hydrogen, enough to power a million fuel cell cars for a year. It would not really be that erratic, continuous wind surplus periods would typically last for many hours, sometimes even days.
        That’s of course if any of my calculations are correct.

      • It doesn't add up... permalink
        November 30, 2020 7:43 pm

        My modelling suggests that for current demand with 40GW offshore plus say 10GW onshore, marginal curtailment rises to around 45%, which means that the effective cost of the marginal wind farm is almost doubled (1/0.55). Total curtailment rises to around 20TWh in a typical year. 5GW of electrolysis at 20% utilisation only get to use 8.76TWh of that. The rest is still discarded.

        The surplus is actually highly erratic, because you have to subtract the varying diurnal demand – so plenty of spare overnight, but not during the daily demand peak. That has to be superimposed on the erratic nature of wind production. The consequence is likely to be suboptimal electrolysis operation. Of course, in low wind years utilisation might fall quite sharply – just when you need stored energy the most.

        But I think you are doing the right kind of sums, even if we disagree on the results through differing assumptions.

  5. November 28, 2020 4:43 pm

    What fascinates me and demonstrates the completely scientific illiteracy of the blind followers of the climate religion who desperately embrace anything sporting the “gween” label without question, is that the fact that Water Vapour, by far and away the MAIN contributor to the unproven greenhouse effect is the product of combustion of hydrogen yet is NEVER talked about in this context and indeed actually promoted as a wonderful “benefit”.

    I supposed compared to the blindly embraced significant emissions producing, part time low tension bird killing unrecyclable wind turbines, any source of energy at whatever the cost is something to be embraced to “fight”…errr whatever they are fighting.

    We now have clearly combine in the religion of climate the dangerous combination of both economic and scientific illiteracy. The question is of course is saving the planet ( from what I have no idea) by stopping the unstoppable climate cycles the real end or a distraction and therefore just a trojan horse to achieve another and darker end?

    • November 28, 2020 5:19 pm

      pardonmeforbreathing , well said! I would add that CO2 is NOT a toxic substance, after all, the air that each and everyone of us exhales has around 4% (~40,000 ppm) of that stuff…

      • Harry Passfield permalink
        November 28, 2020 5:53 pm

        Sorry, Ben, a slight error in your numbers. 400 ppm and 0.04% is what you wanted to say.

      • November 28, 2020 6:19 pm

        @ Harry, Ben is right. 400 ppm is ambient.

        @ Pardon, adding more water to the atmosphere won’t make any difference, because it rains. A warmer atmosphere could in theory hold more water, whence a major feedback might be hypothesized re: CO2 making the atmosphere warmer a tad. Without such postulated feedbacks, there would be no threat at all from CO2, which might raise the atmospheric temp 1 degree if doubled from 280->560ppm.

      • Harry Passfield permalink
        November 28, 2020 9:27 pm

        On second thougghts, if breathing out was a problem Attenborough would be ecstatic.
        Exhaled CO2 is not a problem nor is any other man-made CO2.

      • November 29, 2020 12:46 am

        JT. I know the theory re CO2 BUT……..
        1. The Greenhouse effect has never been proven in the form that it is claimed to work.
        2. Even if it did and man’s effect could be measured (it can not) it would be so small in the overall scheme of things (By this I mean the total effect of the Greenhouse effect on the temp of the Earth. I refer to the work of both Dyson and Happer)
        3. The current joke but serious folks estimate of the Water Vapour contribution globally on any given year to the fabled greenhouse effect is variable between 35-75% ( Something close to those numbers) when the effect quoted for CO2 ( which I have problems with) is around I think 27% and a much narrower uncertainty range.
        That is a 100% error bar for Water Vapour up to 2 x the claimed effect of CO2 which I find difficult to get my head around given the way the electromagnetic signature of Water Vapour completely swamps that of CO2 which is only show as absorbing IR at the ultra low end of the IR part of the spectrum ! Given this error bar of one hundred 100% is it beyond the realms of possibility that the focus should be on water vapour and not the gas of life? Also do you not find it strange given that Water Vapour IS the main fabled greenouse gas that almost no one bothers to refine and understand its potential effect…CO2 however …that is the bad guy because Al Gore and the IPCC sat so.

      • November 29, 2020 1:33 am

        Ben even Oxygen is toxic if not correctly handled….also it makes things “oxidize” quite violently if allowed!

        The demonization of CO2 is remorseless and the pathetic dumbed down term of “Carbon” really annoys me but that was pushed to make people think of coal.
        It is very very difficult to find the truth now about anything and that is deliberate. The atmosphere is just another part of Earth’s geological history and that is where I come in.

        You will never be told for example when the zealots are laying out their “scientific” based arguments ( I use the term scientific in it’s loosest possible form), that the majority of the Earth’s CO2 is not in the oceans or the atmosphere but in organic carbonaceous rocks …many orders of magnitude more. . Those rocks also have almost all been created since the Late Middle Jurassic.

        You will also never be told that only one time in Earths Geological History has the level of CO2 been as low as it is now and that was back in the Ordovician.
        You will never be told that low is NOT normal, far from it in fact and that has consequences which I will allude to below.

        You will also never be told that the average CO2 concentration of the atmosphere over geological time is around 2500ppm and that it was up to 7000ppm during the Cambrian Period.

        You will never be told that Ice Ages came and went even with very high CO2 concentrations in the atmosphere ( relative to today).

        You will never be told that when the angiosperms evolved (the veg we eat) atmospheric CO2 levels were around 2500-2800ppm which is why commercial greenhouses pump CO2 to make the plants grow larger, quicker using less water because right now plants are still starving.

        You will never be told that CO2 is the source of the oxygen we breath and that it is a basic part of the process of photosynthesis, a process which becomes less and less efficient with lower concentrations of CO2 in the atmosphere to a point where the process is compromised at around 160ppm.

        You will not be told that when temperature and atmospheric CO2 are plotted on a real geological time scale there is absolutely no correlation but then why should there be if the physics of the possible limits of effects of CO2 in the atmosphere are adhered to? Geological history provides empirical data based support for the physics which is also empirically supported.

        You will never be told that there IS a problem with CO2 and the Carbon Cycle but that far from there being too much CO2 there is actually a crisis and there is too little.

        You will not be told that this has been going on since the Late Mid Jurassic ( for around a cool 160 million years) caused by the evolution of marine organisms which sequestrate CO2 to create CaCO3, Calcium Carbonate skeletal material or shells.

        You will not be told that they became supremely good at doing this and as a direct consequence this has caused a linear decline in the amount of CO2 in the Carbon Cycle because when they die most of that shelly material ends up in organic carbonaceous limestones and not back in the Carbon Cycle. You and I have been responsible for a very temporary hald in that decline by driving our SUVs. The decline will resume as soon as we stop liberating CO2 previously removed from the Carbon Cycle.

        You will not be told that for the last 800K years life on Earth has been dicing with death, to the point that during the first part of the current Ice Age, atmospheric CO2 levels fell to around 180ppm or put another way, 20ppm above the death of plants on Earth and consequently the end of life,
        You will not be told that when very shortly and naturally without politics we stop buring fossil fuels, that relentless decline in CO2 will resume with the CO2 concentration of the atmosphere hitting the death line for plants in a little over 1 million years from now….. or sooner if the ecofascists get their way.

        The only way to consider CO2 into its correct context with respect to the atmosphere is to at least recognise its variation relative to the three media it is contained within, over geological time and also consider it across a range of areas of science NOT only that hijacked by the climate industrial complex

        By the way and finally there exists today no statistically significant empirical data set(s) which support the hypothesis that 1. man made warming of the planet exists and 2. that even if it did that it is measurable and that by a leap of faith that unmeasured and unmeasurable quantity controls the climate.
        You see as we are still within the Enlightenment no “science” can be progressed and no claim supportable without a statistically significant empirical data basis.

        That basis does not exist therefore that means there is no proof of cause. Without proof of cause, how can there be a proven effect (climate change) Q.E.D.

        Hope I did not put you into a coma…..

  6. November 28, 2020 5:23 pm

    And, how about the costs of transporting and “packaging” H2, not to mention its inherent hazards?

  7. November 28, 2020 5:23 pm

    This argument ignores the fact that the round trip efficiency of the electricity-Hydrogen-electricity cycle is around 30% ie you get back approximately 30% of the electricity that is put into this system . Most commentators try to cover this up by including the heat generated in the electrolysis and re-conversion ( fuel cell) processes, but if this heat cant be used then the real efficiency only applies to the electricity cycle.

    • Graeme No.3 permalink
      November 28, 2020 6:07 pm

      Continuous electrolysers about 62% efficiency which can be improved by the INPUT of heat, so they cannot claim useful heat is available for extraction.
      In THEORY round trip hydrogen back into electricity might be 38% but once you include other costs (compression, storage, distribution etc) I wouldn’t dispute your 30% figure. It puts “green hydrogen” in the norwegian blue category.

    • Sobaken permalink
      November 28, 2020 6:36 pm

      It’s usually proposed that this hydrogen be used to replace natural gas in heating, like burning it in domestic boilers or for industrial high temperature processes, rather than provide electricity from fuel cells back to the grid, so they probably only consider losses during the electrolysis process itself.

  8. Alan D Tomlin permalink
    November 28, 2020 6:06 pm

    Harry Passfield…..exhaled human breath has about 4% CO2 (40k ppm)….Ben Dussan’s number is correct.

    • Harry Passfield permalink
      November 28, 2020 6:15 pm

      Point taken. Missed that he was talking about breathing. Apologies to Ben.

  9. ianprsy permalink
    November 28, 2020 6:59 pm

    What happens to the oxygen produced? It requires equipment even more specialised than that for hydrogen but compressed oxygen has lots of uses.

    • Gamecock permalink
      November 29, 2020 2:36 am

      Oxygen could be vented to atmosphere. It is highly corrosive, so they’ll need to disperse it somehow. Perhaps high stack.

      If you are reducing water, you will get 8 pounds of oxygen for each pound of hydrogen. A lot to deal with. I don’t think any of them have thought about what to do with the oxygen at all.

  10. It doesn't add up... permalink
    November 28, 2020 7:11 pm

    Spanish solar has a typical capacity factor of 17.5%, and of course the reality is that it varies across the day, and across the year from month to month. I have some data on Spanish solar capacity factors covering 30 years of weather data. Summarised, it looks like this:

    Or if you convert it to a duration curve, it looks like this:

    So the problem is how much electrolysis capacity do you install relative to the amount of solar capacity? If you install kW for kW then you will have plenty of down time when the sun isn’t supplying enough energy. If you install a lower fraction then you have to dispose of the surplus solar power – right at the point when it has least value at midday in summer. So the idea that you can solve this with solar is fatuous.

    It is frankly no better with wind. I have linked this chart before:

    It shows how the build-up of surplus wind that could be expected by doubling, trebling…sextupling our existing wind capacity would interact with electrolysis capacity in terms of the utilisation of marginal capacity additions. You need to treble wind capacity if you want to have 1 GW of electrolysis operating at a minimum of 25% throughput. If you install 5GW of electrolysis, that would give about 5% utilisation if you doubled wind capacity.

    The National Grid Future Energy Scenarios have the following even more hare-brained scheme:

    The concept involves floating semi-submersible wind turbines integrated with electrolysis and desalination facilities. The electrolysers will split desalinated seawater into hydrogen and oxygen, with the hydrogen being piped ashore. The use of floating turbines will give access to the most favourable UK offshore wind resources in deep water several hundred kilometres from land.

    I find the analysis of Timera to be interesting: they indicate that the present cost of green hydrogen is of the order of $30/MMBtu, which is about 10 times the Henry Hub price for natural gas. With a large dose of Hopium, the can imagine the cost halving by 2050.

    They have gone on to start to explore the many ways in which this will be subsidised at consumer expense

    The potential structure of support mechanisms is starting to take shape, for example incorporating:

    Fixed or input cost indexed payments to green hydrogen producers that support & stabilise revenue
    Carbon CfDs for industrial buyers of green hydrogen (supporting offtake contracts with electrolysers)
    Favourable charging rules e.g. German plan to exempt electrolysers from grid charges & the renewables levy
    Adaption of other renewable support mechanisms & tender processes to cover electrolysers.

    Of course one way of solving the intermittency problem for electrolysers is to use hydrogen as an energy store, so it can drive a generator to allow electrolysis of more hydrogen…. (!)

  11. Joe Public permalink
    November 28, 2020 7:11 pm

    It’s always amazing how those who wish to obfuscate, tend to mix units to make comparisons difficult.

    A kilo of hydrogen contains 33.33kWh of useable energy – that’s fairly easy to discover via Google.

    Less easy to discover, is the inconvenient fact that even state-of-the-art hydrogen liquefaction technology has a power consumption of 12 kWh/kg.

    This is equivalent to 36% of the useable energy contained in 1 kg of hydrogen.

    • Harry Passfield permalink
      November 28, 2020 7:33 pm

      Which raises the question, is there also a loss in converting the liquid H2 back to a gas?

  12. It doesn't add up... permalink
    November 28, 2020 7:12 pm

    Post with several links just made – Paul, you may need to check the spam bin.

  13. jack broughton permalink
    November 28, 2020 8:53 pm

    Hydrogen burning will increase the humidity (partial pressure of H2O) of the atmosphere. It will eventually fall as rain but the atmosphere will increase its moisture content in a similar manner to the increase in CO2 from human activities. Treating moisture as equivalent to CO2 (in terms of the mythical RFF it is), the greenhouse gas equivalent is emitted whether hydrogen or methane are burned.

    Looks like a case of frying pans and fires. Wait ’til the mathematical modellers get hold of this; no doubt their AlGore-ithms are assuming that the moisture does not affect the atmospheric transmissivity, in a similar manner to where the effects of cloud cover are presently conveniently ignored. Large scale hydrogen burning has the same green-house effect as CO2 (negligible in practice, but massive in climate-fear theories), it will also inevitably alter cloud coverage.

    • Gamecock permalink
      November 29, 2020 11:43 am

      It wouldn’t be beyond the Greens to have us invest trillions in new, alternative energy production, then tell us, “YOU CAN’T USE IT! IT will destroy the planet.”

      “But it’s what you told us to do!”

      “Sorry. We were wrong.”

      “Well, now we are stuck with it.”


  14. Chaswarnertoo permalink
    November 28, 2020 10:12 pm

    H2 is a leaky explosive gas. To make it easier to handle and better to burn why don’t we add some carbon atoms…..

  15. TedL permalink
    November 29, 2020 4:05 am

    Years ago (well, three years ago) I posted my objection to a hydrogen economy in a comment on this very website:

    In a nutshell, I argued that hydrogen production in utility quantities would release so much hydrogen to the atmosphere that it would rise up to the ozone layer and oxidize into water vapor, thus destroying the ozone layer and replacing it with a layer of ice crystals, changing earth’s albedo. I also speculated that this had perhaps already happened a while ago. A comment by a reader named accordionsrule, whom I have not seen post recently, suggested it had something to do with noctilucent clouds.

  16. StephenP permalink
    November 29, 2020 8:25 am

    Interesting detail (from Wikipedia so must be cautious) on the NOx production from hydrogen ICEs:

    The differences between a hydrogen ICE and a traditional gasoline engine include hardened valves and valve seats, stronger connecting rods, non-platinum tipped spark plugs, a higher voltage ignition coil, fuel injectors designed for a gas instead of a liquid, larger crankshaft damper, stronger head gasket material, modified (for supercharger) intake manifold, positive pressure supercharger, and a high temperature engine oil. All modifications would amount to about one point five times the current cost of a gasoline engine. These hydrogen engines burn fuel in the same manner that gasoline engines do.

    The theoretical maximum power output from a hydrogen engine depends on the air/fuel ratio and fuel injection method used. The stoichiometric air/fuel ratio for hydrogen is 34:1. At this air/fuel ratio, hydrogen will displace 29% of the combustion chamber leaving only 71% for the air. As a result, the energy content of this mixture will be less than it would be if the fuel were gasoline. Since both the carbureted and port injection methods mix the fuel and air prior to it entering the combustion chamber, these systems limit the maximum theoretical power obtainable to approximately 85% of that of gasoline engines. For direct injection systems, which mix the fuel with the air after the intake valve has closed (and thus the combustion chamber has 100% air), the maximum output of the engine can be approximately 15% higher than that for gasoline engines.

    Therefore, depending on how the fuel is metered, the maximum output for a hydrogen engine can be either 15% higher or 15% less than that of gasoline if a stoichiometric air/fuel ratio is used. However, at a stoichiometric air/fuel ratio, the combustion temperature is very high and as a result it will form a large amount of nitrogen oxides (NOx), which is a criteria pollutant. Since one of the reasons for using hydrogen is low exhaust emissions, hydrogen engines are not normally designed to run at a stoichiometric air/fuel ratio.

    Typically hydrogen engines are designed to use about twice as much air as theoretically required for complete combustion. At this air/fuel ratio, the formation of NOx is reduced to near zero. Unfortunately, this also reduces the power output to about half that of a similarly sized gasoline engine. To make up for the power loss, hydrogen engines are usually larger than gasoline engines, and/or are equipped with turbochargers or superchargers

    • Coeur de Lion permalink
      November 29, 2020 1:35 pm

      And a serious blast shield all round?

  17. mikewaite permalink
    November 29, 2020 9:30 am

    Considerable engineering and economic information here . But at some convenient time I would like to see a technical discussion of exactly how, in materials science terms , the electrolysis is intended to be carried out. Or a link to such, since I find myself shamefully ignorant of the technical details.
    Liquid or solid (proton conducting) electrolytes . What type of electrode : Platinum group or cheaper Ni-Fe , or maybe something novel involving graphene. Then there is the temperature of electrolysis.
    Many politicians and media “experts” just seem to wave their hands and hydrogen miraculously appears from all that surplus green electricity. But someone has to make it work and on a large scale with all the capital costs that that involves especially if you are using electrodes of Pt-Ru alloy. And if using a liquid electrolyte will you not have to find a method of using or disposing of highly alkaline electrolyte.

  18. Coeur de Lion permalink
    November 29, 2020 10:11 am

    Off thread but today Sunday 29 November is the fourth day of no electricity worth a damn from Boris’s windmills.

    • Chaswarnertoo permalink
      November 29, 2020 10:20 am

      Carrie’s windmills. FTFY. Boris Bunter and his munter…

  19. Gerry, England permalink
    November 29, 2020 1:14 pm

    Since they were required to tell if there is a cheaper deal to be had, I am always finding on my gas bill that there is and it can be worth paying the early exit charge of £30 and still save money. Strangely this never happens with my electricity……

  20. Anders Valland permalink
    December 1, 2020 8:51 am

    If you install 100 MW pv for a 20 MW electrolyser I doubt that the 20/80 split holds. But it does account for the dismal capacity factor of pv.

    What is not present here is that this “green” hydrogen is now produced by an eletrolyser at 5-6 bar pressure. You can not store hydrogen at that pressure, it takes too much space. So you need to do something about that. The cheapest is to compress it, but that would still leave you at 30-40 kg/m3. You could put into a liquid organic carrier, costing a huge amount of heat input but giving you a easily handled liquid. Or you could liquify it to 20 K. All of these options take energy and infrastructure cost. All of it is integral to the “green” hydrogen, because it cannot exist without it. And none of it is cheap. The true cost of green hydrogen need sto incorporate those costs.

    It reminds me of how efficiency number of fuel cells come about. They constantly claim that fuel cells have superior efficiency to ICEs, 60% vs som ridiculously low number. Well, for any large scale operation ICEs have 45-50% efficiency and that is proven. The fuel cell itself ha an efficiency of 50-60% under ideal conditions, but it needs what is known as the BOP – balance of plant – to operate. And this BOP, which the FC cannot operate without, is a net consumer of energy. The FC system efficiency is thus still around 45-50%, comparable to the similar system efficiency of an ICE.

    There is a lot of smoke and mirrors in this green deal.

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