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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

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    • CommentAuthorbxman
    • CommentTimeJan 25th 2021
     
    Hydrogen Boilers, Heat Pumps & The Future of Heating

    https://www.youtube.com/watch?v=4uNKPDREa-Q

    No involvement and uncertain as to the existence of any bias but see what you think,

    It will be 45 mins if you watch to the end

    program notes from Jan 20, 2021 with 65k views to date

    We're joined by Martyn Bridges, Director of Marketing and Technical Support at Worcester Bosch Group, to discuss hydrogen boilers and the future of heating our homes with reduced emissions.

    MORE ON HYDROGEN BOILERS FROM WORCESTER BOSCH

    Why hydrogen boilers?

    But for the heating and hot water industry, removing carbon is much more difficult, largely because of the existing infrastructure, where the majority of UK homes use natural gas for heating

    Yet, with a third of UK greenhouse gases coming from our homes, it is quite clear that the UK will not meet its climate change targets without a change in home heating technology and fuel.

    Replacing natural gas boilers with hydrogen gas may be the simplest solution to the nation’s heating problems. The only by-product of burning hydrogen gas is water, meaning that it is a carbon-free fuel source and could be a key method to help decarbonise heating and hot water in UK homes.

    How do hydrogen boilers work?

    A hydrogen boiler, in theory, can fit into a current boiler’s physical space in the home without much disruption to the homeowner. With a similar build to existing boilers, installers will already have most skills necessary to fit these products too.

    Over the last few years, leading boiler manufacturer Worcester Bosch have not only been advocating for hydrogen, but they have also developed a prototype boiler that can run on 100% hydrogen gas.

    The prototype has been designed to also run effectively on natural gas. This means that in the future if hydrogen gas becomes reality, those who have a ‘hydrogen-ready’ boiler can simply convert to hydrogen without the need for an entirely new heating system.
  1.  
    The prototype has been designed to run effectively on natural gas. This means that the fossil gas boiler industry can continue to flog fossil fuel burners for the next 20 years (at the earliest) until piped hydrogen could be delivered to millions of homes. Those who have a greenwashed 'hydrogen ready' boiler can provide a figleaf for the continuation of the fossil gas boiler manufacturers, but need not expect it will still be working in 20 years time when hydrogen arrives, so will need an entirely new heating system by then anyways!

    http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16786

    To be fair, the CCC see a future for them in the 2050+ timeframe.
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2021
     
    Sorry, 45 mins is too long. Do they say where the hydrogen is to come from and how it could be produced more efficiently than a heat pump with a CoP greater than 1 or even resistance heating with a CoP of 1?

    +1 to WiA's fig-leaf comment.

    I think there's a role for hydrogen but it's a lot more niche than domestic heating or cars, e.g., interseasonal energy storage or on ships.
  2.  
    Rather than burning the hydrogen, wouldn't it be more efficient to run it thru a fuel cell and generate heat and electricity?
  3.  
    Hydrogen can produce NOx due to the higher temperatures. This can be controlled in industrial settings, but I suspect it's more difficult in residential heating. NOx is responsible for smog and respiratory problems ...

    https://www.thechemicalengineer.com/features/hydrogen-the-burning-question/
    https://www.fastcompany.com/1678206/the-hydrogen-economys-dirty-secret

    Much better to use it in a fuel cell as Pile-o-Stone commented.

    Paul in Montreal.
    • CommentAuthorbhommels
    • CommentTimeJan 26th 2021
     
    Posted By: Pile-o-StoneRather than burning the hydrogen, wouldn't it be more efficient to run it thru a fuel cell and generate heat and electricity?

    Yes. Very capital intensive and still more efficient than the simplistic (stupid) option of burning hydrogen.
    •  
      CommentAuthorfostertom
    • CommentTimeJan 26th 2021
     
    Posted By: Paul in MontrealHydrogen can produce NOx due to the higher temperatures
    Higher than what - natural gas? Am I right that gas produces only CO2 and H2O - are we saying that hydrogen can be nastier thasn gas?
  4.  
    Posted By: bhommels
    Posted By: Pile-o-StoneRather than burning the hydrogen, wouldn't it be more efficient to run it thru a fuel cell and generate heat and electricity?

    Yes. Very capital intensive and still more efficient than the simplistic (stupid) option of burning hydrogen.

    Doesn't that depend upon the efficiency %age of the boiler and the efficiency %age of the fuel cell? Also for the general use a combi boiler is affordable without the expense of a fuel cell especially as the grid in getting greener all the time.
    • CommentAuthorbhommels
    • CommentTimeJan 26th 2021
     
    Posted By: Peter_in_Hungary
    Doesn't that depend upon the efficiency %age of the boiler and the efficiency %age of the fuel cell? Also for the general use a combi boiler is affordable without the expense of a fuel cell especially as the grid in getting greener all the time.

    Sure, burning hydrogen in a boiler is the cheap(est) option. It is also the option that delivers the least bang for your renewables-generated hydrogen buck. A boiler will never exceed 100% eff, whereas a fuel cell & heat pump easily does.
    It seems simplistic to me to just burn an energy carrier that a) could solve the electricity storage conundrum, and b) could generate the same amount of heat in a much more efficient way.
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2021 edited
     
    Even with a domestic fuel cell, by choosing to move energy into the house in the form of hydrogen (as opposed to electricity) you're still committed to the inefficiencies of turning electricity into hydrogen and back to electricity all of the time. On the other hand, if you scrap piping gas around completely you only need to go summer electricity → stored hydrogen → winter electricity, or whatever, for those times when direct supply from renewables or more efficient short-term storage (batteries, pumped storage…) aren't sufficient.

    Also, I can't help feeling that big centralized fuel cells are likely to be more efficient and cheaper per watt, though it might be harder to make use of waste heat from them.
    • CommentAuthorJonti
    • CommentTimeJan 27th 2021
     
    I am very much of the opinion that the solution to home heating is ensuring that homes are really well insulated in the first place. Extra heating should only be needed as back ground heat and only for a short periods of time. I am also of the opinion that homes need to become as self sufficient as possible if they are located away from large urban areas but it does make sense to have community schemes in densely populated areas.

    As for hydrogen boilers? As with the present gas ones I think they will possibly be a phase we go through but in the end electricity will be the source that will come out on top.
  5.  
    Posted By: Ed DaviesEven with a domestic fuel cell, by choosing to move energy into the house in the form of hydrogen (as opposed to electricity) you're still committed to the inefficiencies of turning electricity into hydrogen and back to electricity all of the time.


    I thought one of the selling points of domestic CHP fuel cells was that they are more efficient than mains electricity due to the losses that you have with distributing electricity over a huge grid rather than just generating at the point of use?
  6.  
    Afraid that might be more marketing spin PoS. The electricity grid losses are only a few %, whereas turning electricity into hydrogen and back again wastes 10s of %. And the gas distribution grid also has energy wastage similar to the electricity grid.
    • CommentAuthorSimonD
    • CommentTimeJan 27th 2021
     
    There is however still progess on the hydrogen pipe to domestic boilers:

    https://www.theguardian.com/environment/2020/nov/30/scottish-green-hydrogen-fife

    With respect to grid losses, I think they're more substantial than is often assumed. Obviously current grid efficiency is pretty awful, but interrestingly, Tennet, a European company specialising in power transmission says:

    "Grid losses contribute to more than 90% of our CO2 footprint."

    And that:

    "As more renewable electricity is fed into the grid these distances are increasing, as wind and solar electricity is often generated in remote areas, far from where most people consume it.

    Transporting electricity a long way can cause larger grid losses compared to smaller quantities of electricity, or when transporting it over a smaller distance."

    The link: https://www.tennet.eu/e-insights/energy-transition/grid-losses/

    I suspect that part of the reason hydrogen piped through the existing gas network is so appealing right now is that in order to supply the country with the electricity needed to supply for heating, cooking, electric vehicles etc. we'd need an enormous investment in electrical infrastructure in a relatively short period of time. I doubt that privatised companies who prioritise their shareholders are likely to stump up the cash for anything remotely sufficient.

    I wonder whether the possibility is that hydrogen piped through the gas network may save on this kind of infrastructure expenditure or at least support a longer term transition maybe. Who knows.
    • CommentAuthorEd Davies
    • CommentTimeJan 27th 2021 edited
     
    Quoted By: SimonD"Grid losses contribute to more than 90% of our CO2 footprint."
    Well, yes, burning 1 milligram of oil *contributes* to 100% of our COâ‚‚ footprint, too. That's a really idiotic thing for them to say.

    further…Transporting electricity a long way can cause larger grid losses compared to smaller quantities of electricity, or when transporting it over a smaller distance."
    That's a somewhat more sensible point. However, losses in HVDC links (such as those being built up and down the coasts of this island) are not great, something like 3% per 1000km IIRC. The whole island is less than 1000km long (Lizard to Dunnet Head is 975km) and most electricity won't go anywhere near that far most of the time (though when it's windy in the north it's less likely to be in the south and v-v).

    Posted By: SimonDI suspect that part of the reason hydrogen piped through the existing gas network is so appealing right now is that in order to supply the country with the electricity needed to supply for heating, cooking, electric vehicles etc. we'd need an enormous investment in electrical infrastructure in a relatively short period of time.
    Assuming space and DHW heating and EV charging is spread out by variable tariffs this is not obvious to me. Transmission capacity could be one of the factors which feeds into the pricing, though, in addition to demand and variable generation.
  7.  
    Posted By: fostertom
    Posted By: Paul in MontrealHydrogen can produce NOx due to the higher temperatures
    Higher than what - natural gas? Am I right that gas produces only CO2 and H2O - are we saying that hydrogen can be nastier thasn gas?


    Hydrogen burns hotter than methane and that increases the NOx production. Burning natural gas also produces some NOx. Industrial furnaces can be designed to mediate the burning temperature and so reduce the NOx production - it's not clear to me if this (a) needs to be done and (b) can be done in domestic boilers.

    Paul in Montreal.
  8.  
    I suspect that part of the reason hydrogen piped through the existing gas network is so appealing right now is that ....privatised companies who prioritise their shareholders ...
    ...own and operate the gas grid and have realised it's just about to become a stranded asset. Ditto the private companies who sell gas boilers. Greenwash ahoy!
    • CommentAuthorGarethC
    • CommentTimeJan 27th 2021
     
    I believe the pressure needed to supply the same amount of energy through the gas pipeline network with hydrogen would require three times the pressures, which isn't a trivial problem.

    And the line stack (or something), the amount of energy contained in the network at any one time due to the volume of gas in there, is reduced massively by a move to hydrogen, which I understand can be problematic if there are faults or outages (less time to sort them out).

    And our gas network already leaks. It will leak far more hydrogen.

    And hydrogen will be very expensive, even if the electricity used to generate it is near free, relative to current gas prices.

    Long story short, I don't think this is what we should do with renewably generated hydrogen.
    • CommentAuthorgravelld
    • CommentTimeJan 27th 2021
     
    I think we should maintain a list of silver bullets that have been proposed to fix this home heating problem.

    Heat pumps.

    District heating.

    Now hydrogen.

    What will with they turn to next to avoid simply fixing the problem: insulating homes to use less energy?
    • CommentAuthorJonti
    • CommentTimeJan 28th 2021
     
    Posted By: gravelld

    What will with they turn to next to avoid simply fixing the problem: insulating homes to use less energy?


    I completely agree. The emphasis should be on reducing the need for heating not altering the energy source. If all the houses were even just at building regs. standard it would be a big improvement yet still the potential to improve would be huge.

    Done properly the average family home should only need heating on the odd occasion.
    • CommentAuthorSimonD
    • CommentTimeJan 28th 2021
     
    Posted By: WillInAberdeenGreenwash ahoy!

    Greenwashing indeed but I also think it has a lot to do with narrowminded policy making. It smacks to me like another Diesel fiasco looming - lets put all our eggs in one basket and deal with the consequences 15-20 years down the line and make everyone else pay for it!

    I read an interesting article recently about the situation with wood pellet demand and production in Lithuania. While demand has rocketed due to European policy to promote and subsidise biomass as a sustainable energy solution and made a few people very rich, it is having a disastrous effect on both CO2 emissions and the native forests. Lithuania has now gone from being CO2 negative to a CO2 producer. Even with replanting of forests, they're unlikely to see any real positive effect on CO2 emissions until about 40 years of growth. Meanwhile, demand is such that they're cutting down vast tracts of ancient and supposedly protected forests.



    Posted By: gravelld
    What will with they turn to next to avoid simply fixing the problem: insulating homes to use less energy?



    Posted By: JontiThe emphasis should be on reducing the need for heating not altering the energy source. If all the houses were even just at building regs. standard it would be a big improvement yet still the potential to improve would be huge.


    Well, there's nothing like a new shiny high-tech toy to show of and make the headlines now is there? Why do the boring stuff when you can do bling :confused: :wink:
    • CommentAuthorbhommels
    • CommentTimeJan 28th 2021 edited
     
    Posted By: SimonD
    Well, there's nothing like a new shiny high-tech toy to show of and make the headlines now is there? Why do the boring stuff when you can do bling


    Because retrofitting decent amounts of insulation and getting the airtightness down to reasonable levels is really difficult, intrusive and thus expensive for the vast majority of homes? :devil:
    • CommentAuthorSimonD
    • CommentTimeJan 28th 2021
     
    Posted By: bhommels
    Posted By: SimonD
    Well, there's nothing like a new shiny high-tech toy to show of and make the headlines now is there? Why do the boring stuff when you can do bling


    Because retrofitting decent amounts of insulation and getting the airtightness down to reasonable levels is really difficult, intrusive and thus expensive for the vast majority of homes?http:///newforum/extensions/Vanillacons/smilies/standard/devil.gif" alt=":devil:" title=":devil:" >


    And it doesn't feel progressive enough! :bigsmile: But perhaps the next big step will be an iHome, 3D printed retrofit insulation knitted seamlessly into the fabric of the building all via your smartphone app. Now that wouldn't be a bad thing..
    • CommentAuthorJonti
    • CommentTimeJan 28th 2021
     
    Posted By: bhommels
    Posted By: SimonD
    Well, there's nothing like a new shiny high-tech toy to show of and make the headlines now is there? Why do the boring stuff when you can do bling


    Because retrofitting decent amounts of insulation and getting the airtightness down to reasonable levels is really difficult, intrusive and thus expensive for the vast majority of homes?http:///newforum/extensions/Vanillacons/smilies/standard/devil.gif" alt=":devil:" title=":devil:" >


    It is not that intrusive if it is EWI. As to the costs, which one of the alternatives cost significantly less to install and run over the following 25 years?
    • CommentAuthormarsaday
    • CommentTimeJan 28th 2021
     
    Sorry not read all the comments here, but i watched this video last week. Very enlightening.

    Hydrogen makes sense to me for the sole reason, getting the existing housing stock off FF is likely to be to hard in reality. Yes heat pumps for NEW builds, that is a no brainer. But what about the solid walled stone or brick stock in the UK. We have millions of them.

    A big point in the video is that the current gas network in the UK is worth 400BN. It is not cost effective to get rid of it. Going over to hygrogen for most homes in the UK will cost 150bn. Expensive, but not as expensive as getting rid of the infrastructure.

    Leeds is to be the test bed for hydrogen. It has been in the planning for years it seems. The project is called H21. Here is the link: https://www.h21.green/

    The cost of moving over to hydrogen on a hydrogen ready combi is £85 plus an hour labour. So the cost to the domestic user is low.

    It seems hydrogen is the way forward.
    • CommentAuthorGarethC
    • CommentTimeJan 28th 2021
     
    Hmm, much of what I've seen argues otherwise.

    The cost of the gas network is a sunk cost. The money has already been spent. It would cost the consumer nothing to ditch it. In fact, you'd save money by not having to maintain it.

    To switch to hydrogen, the network would have to be upgraded massively. New pipes, new, more expensive compressors and even better leak protection. That will cost a fortune.

    Even if the hydrogen is created with near free renewable electricity, which it won't be in the quantities we need, the hydrogen will cost several times what natural gas currently costs, and we'd need incredible quantities thereof. So the running cost to the user rises massively.

    I believe, although could be educated to the contrary, that NOx production from burning hydrogen in a domestic setting is a problem.

    I've much to learn, but I'm not persuaded currently I'm afraid...
  9.  
    Posted By: marsadayA big point in the video is that the current gas network in the UK is worth 400BN. It is not cost effective to get rid of it.

    Not getting rid of a redundant asset because it is valuable doesn't make sense - unless you have shareholders who want their profit.

    Insulating homes is expensive for the householder, 10s of thousands with an ROI of 25 years and with people moving house every 10 years or so and not much uplift on price it's a hard sell. Also insulating a house gives profit for the insulating co. and nothing for the energy co. - ever.

    On the other hand sell the householder a hyd. boiler - 1.5 grand or ASHP a couple of grand more = profit for the manufactures and profit for the energy co. for the foreseeable future.

    Hmm - I'm not sure which way big business would want to push this.........but I can guess.
    • CommentAuthormarsaday
    • CommentTimeJan 28th 2021
     
    <blockquote><cite>Posted By: GarethC</cite>Hmm, much of what I've seen argues otherwise.

    The cost of the gas network is a sunk cost. The money has already been spent. It would cost the consumer nothing to ditch it. In fact, you'd save money by not having to maintain it.

    To switch to hydrogen, the network would have to be upgraded massively. New pipes, new, more expensive compressors and even better leak protection. That will cost a fortune.

    Even if the hydrogen is created with near free renewable electricity, which it won't be in the quantities we need, the hydrogen will cost several times what natural gas currently costs, and we'd need incredible quantities thereof. So the running cost to the user rises massively.

    I believe, although could be educated to the contrary, that NOx production from burning hydrogen in a domestic setting is a problem.

    I've much to learn, but I'm not persuaded currently I'm afraid...</blockquote>

    I said the cost is £150bn to hydrofi the current network.

    Have you watched the skill builder interview. For me it makes total sense. They talk about the limitations of heat pumps. This is real life stuff they are talking about. I think in a free upgrade to heatpumps only 14 houses went for it out of a few hundered offered (i would need to watch it again). So heat pumps are only good for new builds.

    What is the answer for all you educated peeps on renewables ?

    How do we provide heating for our CURRENT housing stock. I am not interested in new build because this is not an issue. The issue is the current stock.
    • CommentAuthormarsaday
    • CommentTimeJan 28th 2021
     
    Not getting rid of a redundant asset because it is valuable doesn't make sense - unless you have shareholders who want their profit.

    So its ok to trash the shareholders assets is it , without compensation. These shareholders are just you and me at the end of the day. General pension holders (although i am not one yet). So this point you make is not throw away, it is central to economic rules. Would you be happy for me to come along and move into your house and tell you to do one.

    The value of the network is £400 billion. You cannot just discount this.
    •  
      CommentAuthordjh
    • CommentTimeJan 28th 2021 edited
     
    Posted By: GarethCthe hydrogen will cost several times what natural gas currently costs

    It will also cost more than the electricity that is used to make it.
   
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