The global race to produce hydrogen offshore

Posted: February 13, 2021 by oldbrew in Energy, hydrogen, wind
Tags: ,

Offshore wind farm [image credit: Wikipedia]

Production will obviously be as intermittent and therefore as unreliable as the wind itself. And how does the hydrogen get back onshore? Yet more expense is implied. Or if the plan is to use ‘excess’ energy, that suggests power already being sent to the national grid, so why not produce the hydrogen onshore?
– – –
Last year was a record breaker for the UK’s wind power industry, says BBC News.

Wind generation reached its highest ever level, at 17.2GW on 18 December, while wind power achieved its biggest share of UK energy production, at 60% on 26 August [Talkshop comment: cherrypicking].

Yet occasionally the huge offshore wind farms pump out far more electricity than the country needs – such as during the first Covid-19 lockdown last spring when demand for electricity sagged.

But what if you could use that excess power for something else?

“What we’re aiming to do is generate hydrogen directly from offshore wind,” says Stephen Matthews, Hydrogen Lead at sustainability consultancy ERM.

His firm’s project, Dolphyn, aims to fit floating wind turbines with desalination equipment to remove salt from seawater, and electrolysers to split the resulting freshwater into oxygen and the sought-after hydrogen.

The idea of using excess wind energy to make hydrogen has sparked great interest, not least because governments are looking to move towards greener energy systems within the next 30 years, under the terms of the Paris climate agreement.

Hydrogen is predicted to be an important component in these systems and may be used in vehicles or in power plants. But for that to happen, production of the gas, which produces zero greenhouse gas emissions when burned, will need to dramatically increase in the coming decades.

Mr Matthews says his firm’s project is just getting going, with a prototype system using a floating wind turbine of roughly 10 megawatt capacity planned, but not yet built.

Full article here.

  1. aletho says:

    Weren’t some of the German offshore installations extremely difficult and costly to connect?

    Perhaps they plan to install more turbines without adding more cables.

    Still an elitist boondoggle.

  2. JB says:

    Something about the local glass recycling dumpsters comes to mind. How they just sit there waiting to be filled up, overflow from lack of efficient monitoring, plenty of spillage, sorting and other technicalities.

  3. gbaikie says:

    An ocean settlement needs lots fresh water and electrical power, it doesn’t need hydrogen, but needs battery storage for electricity from unreliable wind energy.
    Anyhow, what ocean settlement needs is a cheap floating breakwater and one might even want cheap floating breakwater for the wind farm.
    Main thing breakwater does is stop big waves and to be cheap it should less less the 1 ton per foot of the perimeter of breakwater {or 1 ton per foot is about $1000 per foot or per mile, 5280 times 1000 is
    5.28 million dollar per mile.] And big waves are motion under the surface of water.
    If had a structure blocking waves, you could think about using that wave energy, but I would first focus making a breakwater as cheap as one can, and after that, then consider getting power from wave as a possible “add on” to it.

  4. Gamecock says:

    ‘Wind generation reached its highest ever level, at 17.2GW on 18 December, while wind power achieved its biggest share of UK energy production, at 60% on 26 August [Talkshop comment: CHERRYPICKING].’

    Exactly. The peaks, which they brag about, are far less important than the minimums. With intermittent supplies, it’s the VALLEYS you still have to deal with. Even if it produced 300% on 26 August, it’s what they produced on the lowest day that matters.

  5. gbaikie says:

    One could make breakwater the foundation of wind mill, and later have it be a foundation of whatever generate wave energy, have been big circle, within in put secondary breakwater {because wind power has to be widely spaced} and put settlement within it. And settlement could also have a freshwater lake. And airport.

  6. gbaikie says:

    Oh, also within 5 km outside of it {the wind mill perimeter}, a sub-orbital spaceport and orbital spaceport. A Spaceport could use liquid hydrogen, but the Starship uses liquid methane.

  7. oldbrew says:

    gbaikie – airport and wind turbines at the same site doesn’t sound good 😬

  8. oldbrew says:

    Latest from UK gov green loony department…

    The Ten Point Plan for a Green Industrial Revolution (HTML version)

  9. ivan says:

    Strange how they never give a reasonable explanation of just why there is a need for hydrogen especially considering its explosive nature when mixed with a little oxygen – not the sort of gas I would want to use in a domestic situation.

    As for the green industrial revolution there isn’t one, since everything will be running on ‘on and off again wind power’ there will be no industry to make anything in the UK or Europe so everything will have to be bought from China which will be problematical since the countries will be broke.

  10. Graeme No.3 says:

    Hydrogen generation by (continuous) electrolysis is about 62% efficient maximum. (Intermittent hydrolysis is more like 38% efficient). Converting that hydrogen back into electricity using a fuel cell (60% efficiency) means 37% return. But using intermittent electricity would mean less than 23% return.
    As for supplying other uses wouldn’t the user be looking for a reliable supply, not one only available when a gale is blowing?

  11. Gamecock says:

    “As for supplying other uses wouldn’t the user be looking for a reliable supply, not one only available when a gale is blowing?”

    Ouch! It would be even MORE intermittent!

  12. oldbrew says:

    ‘But what if you could use that excess power for something else?’

    How do you know when it is ‘excess’, and when it ceases to be so?

  13. Gamecock says:

    I consider ‘excess power’ to be a cruel joke. You will be energy starved.

  14. gbaikie says:

    “airport and wind turbines at the same site doesn’t sound good ”
    Well, I was kind of thinking of a small airport, but let’s go big. a airport like international
    airport or large airport which could costs billions of dollars.

    And 1/10th billion [100 million] for breakwater. 100 / 5.28 = 18.94 miles,
    10 mile in diameter 31.16 miles. So have 1/2 circle which is 10 miles wide.
    And about 50 to 100 meter out further out is wind mills or wind mills as part of breakwater
    itself or wind mill within the breakwater.
    Length of international airport runway is:
    ” Runway dimensions vary from as small as 245 m (804 ft) long and 8 m (26 ft) wide in smaller general aviation airports, to 5,500 m (18,045 ft) long and 80 m (262 ft) wide at large international airports built to accommodate the largest jets,”
    Large being 3.41 miles.
    8 MW = 250 meters high
    What descent angle of take off or landing “Planes slowly angle up during take off at about 2-3 degrees per second for a Boeing 747. A bit of quick math and using the same Boeing 747 as an example, the average passenger plane has a maximum take off angle of about 10-15 degrees. ”
    100 meter per second, speed is 223 mph. Say 100 meter up per km horizonal travel, 3 km being 300
    meters. Where to put it?
    This is complicated:

    They say is need ahead of you in case you need to abort 1521 meter past take off , need 1521 meter ahead you to stop plane if have abort take off. It mention once 10 meter above runway one can do fairly steep climb. So you still on second part 1521 meter runways and going up 10 meters above it, then can steeply climb. And they mention runways are designed depend on common wind direction and some mad fools elsewhere on internet want make circular runway so it handle any wind direction. Oh, video basically said circular runway is bad idea.
    Hmm Forbes says:
    “the NAL team suggest a minimum diameter of 3.5 km (2.17 miles)*, which compares pretty favorably with the ‘typical’ length of a commercial airline runway ” Whereas could make 8- 9 km in diameter.
    Or make breakwater 9 km long legs and upside down and flattened “V” shape and blunt “point” .94 km wide which roughly like 10 mile diameter half circle, and have windmills on breakwater. runway running parallel and 200 meter way from breakwater. And add runway making “base” of triangle.
    Have arrival/departure at 3 corner. And roughly fill corners fill airport buildings and lanes for planes.
    But in middle one could be a lake and non airport stuff. and landing and take off paths aren’t going over residential areas. but airplanes while on “ground” could about 1 mile away.
    Or go with a small airport.
    And any in video mentioned London airport was add a runway [and demolish residential area] and
    costing 3.8 billion dollars. One could easily expand an airport size in the ocean. And if close enough to a coast you providing some benefit {or wrecking any surfing] to areas between it and coast. And generally assuming this is at least 5 miles off a coast

  15. pochas94 says:

    Doesn’t make sense to me. Why not make hydrogen onshore from the power generated offshore. Better yet, locate electrolyzers near consumers and dispatch excess off-peak power to make hydrogen, whether from the windmills or not.

  16. oldbrew says:

    Why not make hydrogen onshore from the power generated offshore.

    Indeed. If it’s a dedicated offshore site for hydrogen only, it can’t be ‘excess power’ as it’s not linked to the grid, so the whole argument is redundant.

  17. It doesn't add up... says:

    We are already at the point where wind generation can exceed what can be accommodated on the grid at times when it is windy. Part of that is simply grid constraints, especially when the Western Link HVDC is down. Part of it is simply that the grid must have sufficient inertia to avoid the risk of blackouts from rapid frequency excursions when key assets are tripped out. In response to the August 9th blackout the grid have proposed a minium level of 140GVAs of inertia, or just over 7 seconds of energy at a demand low of around 18GW. Wind must be curtailed to let the inertia providers in, and in summer the effect of uncontrollable zero inertia solar will lessen the space for wind. We may gain a small amount of extra headroom by exporting over interconnectors, but the export price is increasingly negative, as when we have surplus renewables it is likely that the Continent does as well. So it becomes an issue of cheapest to curtail.

    Last year some 3.7TWh of wind was curtailed. As wind generation starts to leap ahead to meet the ambitious targets for capacity that is only going to get a lot worse. If we meet the 2030 target we could be curtailing 30TWh a year, equal to over 10% of demand, and the marginal wind farm would effectively see half its output curtailed, doubling the cost it must recover from actual production.

    These awkward facts lie behind the push for hydrogen storage. The quantities involved would overwhelm anything that could be managed with batteries or the limited amount of extra pumped hydro we could access (including limitations on how much the Norwegians are prepared to accept via interconnectors: already they had to close the border to excess renewables for fear of overtopping their reservoirs, and they are not looking favourably on a second interconnector to Scotland). In theory at least we could leach out more salt caverns for hydrogen.

    But the practicalities of production from wind are not that great economically. Surplus wind is a highly intermittent commodity, and the amount of surplus is highly variable, depending on the changing strength of winds and variations in demand through the day. In any event, it must be paid for, either through replacing the curtailment payments we have currently, which run around £70/MWh, or through boosting subsidies via higher prices for power supplied. The very variable nature of the surplus poses two problems: varying supply to electrolysis results in much lower efficiency than establishing a steady state process, and you have to decide how much capacity you are going to build relative to peak power available. Build a little, and you will be able to benefit whenever there is a surplus, but most of the surplus will still have to be curtailed. Build more, and utilisation and efficiency will decrease because full utilisation depends on rarer larger surpluses. Low utilisation and low efficiency kills the economics.

    Which is where the idea of dedicated wind farms come in, preferably with high average load factors (at least if we ignore the cost of floating offshore wind). But even here we are fighting the problem of the duration curve – how much of the time is generation at or above any particular level, and how intermittent us the supply to desalination and electrolysis and pumping to shore. You can disguise it a bit by using smaller generators relative to turbine size, as they will reach peak output at a lower wind speed. You end up with higher generating costs because you are building large turbines and throwing away more energy through feathering the blades at higher wind speeds to avoid overloading the generator.

    Of course, floating offshore wind may hold the prospect of 50% or more capacity factors. But it is not cheap. The Hywind project gets 3.5ROCs per MWh, or over £175/MWh in subsidies. Equinor have been quite clear that they expect it will continue to need subsidies as a technology. So we have an expensive technology feeding an inefficient process that will produce very expensive hydrogen. All that is before you even look at getting it ashore, distributing and storing and using it.

  18. gbaikie says:

    “Doesn’t make sense to me. Why not make hydrogen onshore from the power generated offshore. Better yet, locate electrolyzers near consumers and dispatch excess off-peak power to make hydrogen, whether from the windmills or not.”

    Or I guess one could ask, does it ever make sense to use wind energy whether on onshore or off shore?
    I think off shore could make more sense than onshore or there could be a greater possibility that off shore could possibly make some sense vs onshore.
    Or onshore has inherent disadvantages.
    One problem with solar and wind is they take up too much land area.
    If a goal in life is to limit amount land area {drive up land area value due to created shortage
    of land area} getting government to pay you to use up land area, makes some twisted sense.

    The other problem with wind and solar is they make energy at the “wrong time”. And wrong time in terms what hours of day and wrong time term percentage of 24 hour day.
    Wind is all over the place, solar is easier to talk about and basically with solar you get solar energy 25% of 24 hour day- or peak solar hours is about 3 hours before noon and after, as rough average or “at best”. If you get solar energy at night or 1/2 of night, one argue it’s better than midday, but just getting 25% of any time of 24 hour period, is not good.
    So, electrolyzers {or anything functions something like battery] is an attempt to solve “wrong time”.

    I am interested in topic of mineable lunar water, and problem of mining anything in space is cost
    of electrical power in space, it starts at around 10,000 times costs on Earth. Or “good price” of Kw hour of electrical power in Lunar polar region is about $100 per kW hour.
    But $100 per kW hour is only good price if you get the power whenever you need it- it does not mean only available for 1/2 a day. Or trying to make X amount in year, and with only 1/2 year to do it in, you twice as stuff on Moon to do a year worth of stuff. Or everything you put on the moon is very expensive, and you don’t want it idle. And other than Moon is extreme example, the same applies for
    Earth. Fortunately with lunar polar region you can get solar energy near 100% of the time, that makes lunar water more mineable.

  19. H is for Hindenburg
    Welcome to H2

  20. Gamecock says:

    It doesn’t add up … there will have to be payments to the inertia providers, to keep them around. At higher penetration of renewables, conventional sources will close, moving their generation assets elsewhere. Special deals to renewable generators can only be made when they are supplemental sources. Catch-22: Should they approach being the primary source, one will realize they can’t be the primary source.

    For Britain’s sake, it might be best to push hard for it, because the powers-that-be aren’t going to learn it the easy way. The sooner they get their wish, the sooner they will abandon it, and go back to rational energy supply.

  21. oldbrew says:

    *Making sense* and *renewables* don’t belong in the same sentence, whether in terms of economics, performance or reliability.

  22. pochas94 says:

    with wind you have perpetual, widely dispersed, invasive, noisome, exceedingly expensive maintenance costs. Keep your power production centralized instead. Or perhaps you enjoy inflicting burdens on your subjects, keeping them fearful and compliant.

  23. oldbrew says:

    Frozen wind turbines trigger Texas blackouts
    Date: 15/02/21 GWPF, Reuters & Austin American-Statesman

    The Texas grid operator has announced rotating blackouts amid winter storm and frozen wind turbines
    – – –
    Oil and gas-rich state can’t keep the lights on any more. Waiting for hydrogen?

  24. pochas94 says:

    Oldbrew, I used to think hydrogen is a long way off while fossil fuels remain cheap and abundant. I may be wrong.

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