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Agriculture Salt Storage / Biochar

Published on November 13th, 2012 | by Cris Pond

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How To Reverse Global Warming With Heat

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November 13th, 2012 by
 
 

Most people know what anthropogenic global warming is. Even climate deniers have some idea of how it works, though they may pretend it’s not happening. The technical details of anthropogenic global warming are as follows:

  1. Humans produce atmospheric carbon through burning things and making cement.
  2. This atmospheric carbon blocks the escape of black-body radiation coming from the earth which would otherwise cool it.
  3. Surface temperatures on earth increase.

There’s obviously a lot more to it than that, but this is the basic science behind it.

A lot of people are operating under the mistaken assumption that moving the human production of CO2 to zero will fix the problem, but this is not necessarily true, for several reasons.

  1. The sun continues to push more energy to the earth year after year.
  2. CO2 stays in the atmosphere for many years and continues to block black-body radiation from the earth.
  3. There are climatic feedback loops primed to release more carbon as the temperature increases.

For earth to remain habitable, and for us to continue to enjoy our lifestyle, we must be removing carbon from the atmosphere, not simply reducing the amount we add. Unfortunately, there are not many known ways to reliably do this. One way that is known, however, is pyrolysis.

Pyrolysis is the exposure of organic material to heat in an anaerobic environment. Without oxygen, high-energy hydrogen compounds break off the organic material and leave relatively inert carbon behind. This resulting material is known as biochar, and is reputed to be wonderful fertiliser, as well as a sink for carbon that would otherwise escape back into the atmosphere.

More information on biochar here.

Another thing that heat can be used for is energy storage. Renewable sources of energy face a huge hurdle in replacing chemical fossil energy because they are not available on demand. One of the ways engineers have gotten around this is to store energy from the sun in the form of molten salt. These solar thermal designs have proven their ability to provide 100% renewable baseload power.

Check out the Gemasolar 24-hour solar plant.
 

 
If we were to combine thermal storage of renewable energy with pyrolysis of sewage, garbage, and agricultural waste, it would have the following effects:

  1. Reducing the amount of CO2 in the atmosphere.
  2. Enabling the complete replacement of baseload coal and other dangerous fossil fuels.
  3. Creating 100% carbon-neutral chemical energy for applications which need it, like remote motorised transport and home heating.
  4. Reducing the need for oil and natural gas–based fertilizers.
  5. Reducing the amount of nutrients in rivers, which are causing algal blooms, and eliminating dangerous bacteria from sewage, bacteria which are poisoning wildlife.
  6. Eliminating the need for fossil fuels to create things like silicon, steel, concrete, and other heat-intensive industrial activities.
  7. Eliminating almost all garbage.
  8. Leveraging existing natural gas pipelines and traditional steam and natural gas turbines to make the transition as inexpensive as possible.

The configuration of heat storage, pyrolysis, and manufacturing could be done in any number of ways:

One might take the industrial heat from smelting or raw materials production and store it to create electricity later. One might produce biogas directly from electricity and export it or store it to generate power when needed.  One might immediately oxidize the biogas created to generate a two-phase, ultra-efficient electrical generation system in the manner of combined cycle natural gas power plants.

If society were to do any of this, it would be a win-win-win-win-win-win-win-win scenario.

Images: Halotechnics Energy Storage, Terra Preta Wikipedia

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About the Author

Cris Pond is a computer engineer and GIS specialist living in San Francisco, CA. He aspires to be a notorious eco-nerd, saving the earth with a sense of humour.



  • http://twitter.com/Tmacoctavius Thomas McInerney

    Cris

    I agree storage is an issue but there already is one “budding” solution:

    Night time wind excess + Widespread adoption of EV plugged in at night
    = Storage.

    All those electrons are stored in the battery.

    Then later when grid needs those electrons back:
    “EV to grid” can then buy back some of those “cheap” nite electrons from my car that is fully charged and sell “dear” electrons during peak power. Later I charge again to full capacity, or I instruct my car to hold onto them if I need to extend my 10 mile commute for whatever reason.

    Tom

    • Cris Pond

      Batteries are an extremely efficient way to store energy, and if we have spare battery capacity, we should definitely use it.

      The problem with buffering energy with car batteries is that most people are going to want to use their cars during the day. They aren’t going to want them powering the grid.

      … and also, this scheme only reduces the amount of carbon produced, it doesn’t actually remove carbon from the atmosphere.

  • http://www.facebook.com/john.bailey.9404362 John Bailey

    The only way to remove enough CO2 is by accelerating the Biological pump of the Ocean, so we patented a Mechanically Produced Thermocline.

    • Cris Pond

      Cool! How does it work?

      I’ve always thought the ocean was going to be the key to locking carbon down. It certainly has been in the past, with limestone and chert deposits.

      I figured the best thing to do with the graphite produced by pyrolysis would be to chuck it into deposition zones if you ran out of uses for it, and it looked like it was oxidising too fast. Just let it be buried by silicates…

  • Dave2020

    This looks like a no-brainer for distributed storage in future? Maybe a single pack would spread a household’s PV through the night?

    http://climatecrocks.com/2012/11/16/for-car-batteries-an-afterlife/

  • http://www.facebook.com/brian.cartwright.54 Brian Cartwright

    Biochar is starting to gain traction with many small-scale projects worldwide — I’ve collected lots of links here:
    http://pinterest.com/nnumeric/what-is-biochar/

    I would caution that “geoengineering” ideas can easily backfire in political discussion. Pyrolyzing sewage, garbage and agricultural waste may work but there are enormous challenges to be met for environmental safety.

    • crispond

      Wow, that is a huge number of resources! Thank you!

      We are already well into our human geoengineering experiment, and have been since the 18th century. It’s time to start fixing the system we’ve broken.

      What environmental safety issues do you expect in pyrolysing sewage, garbage and ag waste? … besides the emission of carbon monoxide, of course. It’s fairly simple to burn that stuff off.

  • Sean

    bio char is cool, but a good alternative is digester sludge, which creates methane at far lower temperatures (lower than 80C) and can be stored much more easily
    its major problem is the digestion of wood (Lignin doesn’t digest very well)
    Both are forms of anaerobic decomposition but I suppose Biochar has a better ring to it than Sludge

    • crispond

      lol! I like the bio digesters too, but from what I understand, pyrolysis is better at making lower carbon chemical energy (lots of pure hydrogen)… and it’s better at chewing up wood as you said, which makes up a huge percentage of our waste (think paper towels, napkins and toilet paper).

      If you assume there’s going to be a lot of surplus wind and solar power at various times during the day, it makes more sense to me to steam the waste with it instead of just shutting down windmills.

  • arun1

    The worry is that if the globe gets too warm, plants will start to pant , ie take oxygen and breathe out co2 to keep cool.
    So we need to go now on a war footing to build wind and solar farms on a war footing and 200mph underground trains linking all cities for fast travel propelled by wind and solar energy.

    • crispond

      There are all kinds of feedback loops just barely starting to kick in. Building wind and solar is half of what needs to be done. Storage is absolutely critical for ending fossil fuel use (and helping provide power to people who are isolated by downed power lines if the storage can be distributed).

  • Dave2020

    “Another thing that heat can be used for is energy storage. Renewable sources of energy face a huge hurdle in replacing chemical fossil energy because they are not available on demand. One of the ways engineers have gotten around this is to store energy from the sun in the form of molten salt.”

    Another way to get around that problem is ‘cold’ storage – similarly, BEFORE-generator, like molten salt. This would also provide “100% renewable baseload power”, but at lower cost.

    It can be done very simply by integrating an air pressure/raised-weight/vacuum accumulator in all floating wind/wave installations. = electricity on demand from marine renewables.

    Everyone who understands electricity market and grid operation knows that a relatively modest level of these types of energy storage (i.e. before generator) will dramatically improve system stability and efficiency.

    Better still, build in a little excess capacity and you’ll make the rest – first nuclear, then fossil fuels – uncompetitive, and create price stability 24/7. That could put all the ‘gamers’ out of business.

    http://www.guardian.co.uk/business/2012/nov/13/whistleblower-gas-price-rigging-allegations

    Don’t let these parasites bleed the electricity ‘markets’ as they did (and still do) to the financial ‘markets’.

    And naturally, biochar as well.

    • crispond

      I think you’re talking about distributed storage, right? Compressors create heat which drives your efficiency way down if it’s not stored. Since transmitting electrical energy is so incredibly efficient, to my mind, it makes more sense to concentrate all that energy with electricity into a large centralised storage unit and take advantage of the economies of scale.

      Using a dual compression-heat storage system could feasibly make sense. The larger the heat differential, the greater the efficiency.

      As far as policy goes, I prefer a carbon tax, but it has to be global. If everyone’s not on board, people will game the system, as you said. :S

      • Dave2020

        Distributed storage, yes. Compressors, no. In my design the floating VAWT drives direct to a variable displacement water pump that controls its speed of rotation and can bring it to a standstill when necessary. i.e. No aerodynamic or friction brakes. The wave energy converter is essential for the stability of the vessel. It also pumps up the raised-weight accumulator, which forms the body of this vessel. Air pressure is optional – only utilised to enhance energy density, if that were beneficial.

        True, transmission losses aren’t a big issue, but additional grid infrastructure is. e.g. If the existing hydro pumped storage in Norway is to be used to store surplus electricity from marine renewables in the North Sea, the HVDC interconnector would cost at least £1bn. With energy storage before-generator you save that capital outlay, plus the running costs and losses (up to 30%) inherent in transmission/conversion/reconversion/retransmission. That easily outweighs any economies of scale you may get on large centralised grid storage. (wrong place – probably wrong technology too?)

        Centralised storage, like pumped hydro, is good enough for centralised generation, like nuclear. Distributed storage has a natural synergy with distributed renewables.

        Sure, a carbon tax is a given, to reflect the true cost of fossil fuels. My beef is with state intervention designed to socialise the investment risk in infrastructure build. The banks were and are too big to fail. Essential energy infrastructure is too important to be left to the vagaries of manipulated markets.

        Markets thrive on volatility. If your electricity supply can respond automatically to demand 24/7 and the ‘fuel’ input is ‘free’ and sustainable for ever, the gamers would have to find another ‘market’ to play with.

        • crispond

          If you aren’t storing the energy with compressed air, how are you storing it?

          I heard about the Norwegian hydro storage deal. It sounds fascinating. You wouldn’t have those transmission costs though if you used thermal storage/biochar. You’d just site it near population centers (cos that’s where all the trash comes from and where all the energy’s used anyhow).

          I don’t think renewables have quite such an easy road economically. It’s still easier to dig up fossils and set them on fire than it is to get your energy from renewables. Coal and natural gas are still cheaper (note the total system levelised cost of things like onshore wind does not include the required storage):

          http://en.wikipedia.org/wiki/Cost_of_electricity_by_source

          Renewables aren’t aren’t out-of-the-ballpark more expensive though. All you’d need to do would be to double the cost of suicidal fuels like coal and you’d drive it right out of the market completely (whilst at the same time bringing down the cost of renewables as economies of scale ramp up).

          • Dave2020

            This is the raised-weight accumulator in principle:-

            http://www.gravitypower.net/

            But it wouldn’t be used in this specific form.

          • crispond

            OIC! So it’s basically pumped hydro, but done in a human-made containment facility, right? You threw me off when you were talking about floating vertical axis turbines… wait, were you talking about using the gravity of the machine itself to store energy?

            Pumped storage is much more efficient than thermal storage, but it still seems like larger units near population centers would be more efficient and less expensive.

          • crispond

            Oh, crapsnacks, you’re talking about filling a huge bladder with air way underwater and using that to store energy! That’s genius!

            Do you have a full design? Is it tethered or embedded? Is there anyone else doing it? Wait, Simpsons did it:

            http://www.ecogeek.org/component/content/article/3522-energy-bag-offers-new-storage-for-wind-power

          • Bob_Wallace

            ” Coal and natural gas are still cheaper (note the total system levelised cost of things like onshore wind does not include the required storage)”

            Wind does not require storage. Unless you want to propose building a grid powered by only (or mostly) wind. We have sufficient storage and dispatchable generation currently to allow us to convert 25% (Eastern grid) to 35% (Western grid) of our generation to wind and solar.

            If one wants to make a decision as to what type of generation to bring to the grid in the next several years wind (0.096/kWh) is cheaper than coal (0.1122/kWh).

            Furthermore, coal has very expensive external costs which we pay with tax money and health insurance premiums.

            I wonder about the data in the Wikipedia post your linked. It states wind capacity at 34%. On the EIA open source data page they list median capacity at 40.35%. New wind farms are turning in much higher capacity factors due to better siting and technology. To use a number lower than median and project it forward is questionable.

            http://en.openei.org/apps/TCDB/

          • crispond

            I am suggesting we power the world with close to 100% renewables. Not doing so is not even an option. I take your point that gathering energy from diverse renewable sources will limit the amount of storage needed, but sometimes the wind doesn’t blow AND the sun doesn’t shine. You need storage for these cases. Until you build that into the price, you can’t even compare the cost between coal and wind. It’s an apples to oranges comparison, regardless of capacity factor.

            I agree that in both the long and the short term, coal costs orders of magnitude more from groundwater pollution, habitat destruction, asthma and carcinogenic particulate pollution, before you even get to the incalculable damage caused by the global climate meltdown.

            … but none of that is taken into account by industry. All they care about is dispatchable power. From their perspective, propaganda takes care of the rest. That’s why you aren’t seeing more rapid displacement of coal by wind. If you give them a competitive baseline cost for comparable services, the entire industry of climate deniers will turn on a dime, I guarantee it.

          • Dave2020

            I pretty much agree with everything you say there. Whole system analysis is very important – crucial in fact. As far as energy storage is concerned, we can anticipate the future need. I’ve been saying for years – we should deal with the problem NOW.

            Then we can destroy this silly ‘anti’ argument:-

            http://www.guardian.co.uk/environment/2012/nov/16/john-hayes-windfarms-gas-nuclear?intcmp=122

            “you’re talking about filling a huge bladder with air” – Er, no. I wrote “no” compressors didn’t I? And “variable displacement water pump”.

            Hi Cris, how can I say this in the kindest possible way? You really need to slow down and read stuff more carefully. The answers to most of your questions were already contained in my posts! e.g. If the words “raised-weight accumulator” don’t create an image of the technology in your mind’s eye – google it man.

            “Do you have a full design?” Yes, but just in my head and it continues to evolve, naturally. That’s the only affordable way to do the R&D!

            “Is there anyone else doing it?” That’s always a good question to start with. In respect of my designs, to the best of my knowledge, the answer is no.

            My recent post in The Guardian tells you more, but Osbourne’s empty head is full of hot air:-

            http://www.guardian.co.uk/environment/2012/nov/09/george-osborne-uk-energy-storage

            “Off-shore the ‘state of the art’ design entails a lot of sub-sea superstructure, which serves no purpose other than to hold up the wrong technology. i.e. the orthodox HAWT. The ‘Hywind’ spar extends 100m below the surface and has tons of ballast to keep it stable! The transition from land to sea should start by switching from HAWTs to VAWTs, as Technip have done, but the mainstream industry suffers from a huge inertia to such change – silly buggers!”

            http://cleantechnica.com/2012/08/02/offshore-use-of-vertical-axis-wind-turbines-gets-closer-look-by-sandia-labs/

            http://www.rechargenews.com/business_area/innovation/article296513.ece

            My first post on CleanTechnica was a year ago:-

            http://cleantechnica.com/2011/12/10/why-doe-funded-floating-turbines-may-change-future-of-offshore-wind/

            Click on dave2020 for all comments in my Guardian archive.

            “Pumped storage is much more efficient than thermal storage”. That’s not necessarily true. It is perceived to be so because it’s been in use for years. This is comparable to pumped hydro:-

            http://www.isentropic.co.uk/our-phes-technology

            But as I keep saying – if you don’t generate surplus electricity, you SAVE the cost of storing it on grid. Don’t convert wind and wave power directly to electricity. It really is a dumb way to run these renewables. You obviously don’t need 100% of renewables to have storage in order to run a 100% sustainable grid.

            Don’t forget, the transmission company charges for the use of their network, so only use it when there is demand in the system. That would give you optimal efficiency.

            A philosophical observation, if I may. True sceptics are just as critical of their own understanding of a subject as that of the people with opposing views. A phoney sceptic (and a phony skeptic) forms his or her argument around confirmation bias and/or disconfirmation bias. Congenital liars add smoke and mirrors to hide their (self-) deceit. It’s our job to try to figure out which is which – no easy task, but as a general rule AGW deniers fall into the latter category, if they are ‘anti-science’ and proud of it. (the vocal rump of Republicans and Tories)

          • crispond

            Yeah, but you can’t raise water in a floating structure without lowering the structure itself… That’s the whole idea of a boat.

            Part of the calculation in the amount of energy possible to store in a hydro system is head height. If you double your head height, you double the energy possible to store in the system. The oceans go down as deep as 10km. There is absolutely no way you are going to be able to lift water that high above the surface. That’s what makes the underwater CAES systems so attractive; you have a small and simple amount of machinery that gets you an absolutely enormous amount of energy storage. I think that silly bag in the link I sent you was estimated to be able to store 70MWh of energy! That’s simply amazing.

            You do still have the problem of heat generated by compression, but I’m thinking maybe if they used alcohol or something non-compressible, they could avoid that…

            Although I find the technology fascinating, this stuff still only gets you halfway to the goal. We still have to be removing carbon from the atmosphere and the only reliable way to do that currently is pyrolysis. It makes sense to me that we should at least be capturing some of the waste heat from that process and using it to buffer the electricity supply or to manufacture the things we need, regardless of the storage efficiency.

          • Dave2020

            “but you can’t raise water”. . . That’s why you raise a weight instead!

            There is NO head of water in a raised-weight accumulator.

            A physics lesson: If they used an incompressible medium in “that silly bag”, as you suggest, its energy storage capacity would be zero.

            Think about it.

          • crispond

            I don’t think that’s quite right. Underwater CAES is only partially a true CAES system like you’d find on land. It’s also part gravity-fed. It stores part of its energy in the pressure differential between the air underwater and the air above, but part of its energy comes from the displacement of water. It’s literally raising the entire column of water above it when you inflate the bag.

            There’s no fundamental difference between using water as a weight and using a great chunk of concrete as a weight in a gravity-based system. You could suspend a weight from beneath a platform to store energy like a cuckoo clock, but you would need an absolutely enormous weight to match 10km of seawater and an absolutely enormous platform to keep the machine from sinking. That’s what makes underwater CAES so cool. It’s just a silly bag!

            You could use any fluid with a lower density than seawater in such a system. If it were a non-compressible liquid like alcohol, you wouldn’t need to store the heat resulting from compression, and could make the system much more efficient.

          • Dave2020

            “part of its energy comes from the displacement of water” – No, ALL the stored energy comes from the displacement of water. When you inflate the bag, water pressure acts uniformly on it, from every direction.

            Pump a liquid into the bag and the only force expelling it is the elasticity of the bag itself!

            “There’s no fundamental difference between using water as a weight and using a great chunk of concrete as a weight in a gravity-based system.”

            Sorry, these ‘explanations’ are meaningless. Where did you learn ‘your’ physics?

            You’d only have a “column of water” if it’s contained inside a tube, above the surface. Even then the pressure and flow diminishes as the tube empties. Put a weight at the top and the pressure is constant, from full to empty – a fundamental difference.

          • crispond

            I don’t think that’s quite right either. Part of the energy in an underwater CAES system is used to displace the water, but part of it is used to compress the air. Think of it this way: if you had a rigid underwater bladder instead of a flexible one, you could charge the chamber with pressures exactly equal to the pressure of the surrounding seawater, turn the chamber flexible, turn it rigid again, extract the air to get useful energy, and not displace the water an inch the entire time.

            To think of it another way, you could extract all the energy from a filled balloon using a pressurised chamber at the surface, the water level would return to normal, and you would still have useful energy stored in that pressurised chamber.

            This is kindof how the underwater CAES systems are designed. They compress the air first before filling the balloon… not because they have to, but because they want to extract and store the heat to increase the efficiency.

            If you pumped water into an undersea bag, the only force expelling it would be the elasticity of the bag. If you used alcohol or something else with a lower density, the relative densities would force the alcohol out… just like oil rising to the surface of a glass of water.

            … maybe they could use oil…

            Explain to me the difference in potential energy between a kg of water raised a meter and a kg of lead raised a meter… I would guess this is maybe a 10th year physics question. Younger, maybe if you were in an advanced class.

            The column of water is just meant as a visualisation tool, obviously. In reality, you’re actually raising the entire sea a teeny weeny bit, but it’s hard to envisage that. The system would act the same as if you raised a column of water above the bag by the volume inside the bag.

            If you wanted to do the same thing with a grandfather clock-type weight (still not entirely sure about your design), the weight would have to be the same as the amount of water displaced by the full bag, which could feasibly be enormous. The head (yes, non-fluid gravity systems need a head too) would have to extend all the way down to the ocean floor. You could also have a mega-ginormous weight that was the size of the entire column of water only moving up and down a little bit, but I’m assuming you understand that wouldn’t be feasible.

            Maybe I’m missing something to your design, but if this is what you’re thinking, underwater CAES beats it on materials and cost.

            … also, none of it gets us to negative carbon, whereas pyrolysis does.

          • Dave2020

            “Explain to me the difference . . .”

            The difference is you don’t raise a kg of water in a raised weight accumulator!!! and you don’t raise a kg lump in a hydro pumped store! ! !

            The Gravity Power Module has a much higher energy density – don’t you see? It could be higher still if you arrange to have air pressure on the top of the piston and a partial vacuum on the reservoir side. That element of the design could also be helpful in achieving an ideal neutral buoyancy of the vessel + wind turbine. Then the function of the wave energy converter would be optimal.

            Visualize oil RISING through sea water (Deepwater Horizon). How much potential energy do you see? – next to nothing. It was all dissipated into an ocean of water. Their relative densities are irrelevant.

            Sure, we should be reducing the level of GHG in the atmosphere, but ‘investors’ (read parasites) see no profit in this kind of innovation, so they don’t give a toss. We need all the billionaires and millionaires in the world to be injected with an altruism gene to replace their selfish gene. (Invest in gene engineering?) These hypocrites will never go to Heaven – eye of needle – camel, kinda thing.

          • Cris Pond

            Uh huh, I realise that. I asked you to explain the difference in potential energy between a kg of water raised a meter and a kg of lead raised a meter. What’s your answer? Does the earth care whether a kg is made of lead or clay or water or air or does it pull on every kg the same?

            The Gravity Power Module in the link you sent me is something done on land… but you were talking about some energy storage device on water, were you not? Were you thinking of building some enclosed pipe with a weight under a platform? Why not just dangle the weight from the platform and use the spinning of a great spool attached to the chain to generate energy instead of using the movement of water in the pipe? You wouldn’t have to build all that infrastructure…

            Either way, you’d have to create a weight equal to the water displaced by the bag in a CAES system and extend it from the surface all the way to the seabed to match the energy storage. Both approaches lose in materials and cost. Alcohol would probably lose to air as well, BTW. Air does tend to be free, afterall. It would be more efficient though.

            There was a huge amount of potential energy released in the Deepwater Horizon disaster! Didn’t you see the video of the oil gushing out of the sea floor? You’re right though, it did dissipate into the water, which is why you have to enclose it in a pipe to capture it…

            Relative densities are absolutely relevant to how fluids arrange themselves! If you think they are not, next time you have a salad, please pour yourself some oil and vinegar dressing without agitating it first. When no vinegar comes out, you can lecture it sternly that it should not let its relative density keep it at the bottom of the container and say you expect it to mix itself thoroughly next time.

            Let me know how that works out for you.

            Heaven is pretend, and I don’t have such a low opinion of investors. I think once they break through their denial, they will see the problem as an economic one as well as a moral and social one. Breaking through the denial is tough though, I will say that.

          • Dave2020

            You have the answer – there is no difference, but your question is not relevant to the issue. These are different physical systems – you have been confusing the two.

            CAES: The clue is in the first two letters. “Compressed air.”

            http://www.theengineer.co.uk/in-depth/the-big-story/compressed-air-energy-storage-has-bags-of-potential/1008374.article#ixzz2Cf7bJ4wa

            “In Germany, researchers at Braunschweig University are looking at storing compressed air in salt caverns while maintaining constant pressure using brine fed in from a shuttle pond at the surface.”

            So constant pressure is worth the extra expense, and:-

            “Underwater bags are an attractive option because the sea acts as the pressure vessel.” But this is NOT gravity acting on a raised weight and there is NO “raised” (!?) water. (in any meaningful sense)

            “At depths of around 600m, there will be enough pressure in one 20m-diameter bag to store around 70MW hours of energy.” My design delivers that from seven turbines.

            “The exciting stuff happens when we think about energy storage as an integrated part of a system, rather than a bolt-on subsystem,” he said. “Garvey admits the use of salt caverns for CAES would be cheaper.”

            But he proposes energy storage that is not integral to the wind turbine, but an add-on sub-system that may be some kilometres away, in deep water. If you power the compressor with electricity you have conversion losses. If you create heat there is a cost in recovering it. Don’t compress air; ‘cold’ storage is less complicated, which usually works out to be cheaper and more efficient.

            “The UK should aim to install 200GWh of CAES, with a cost for the energy storage alone of between £0.2bn and £2bn depending on what compressed air stores are adopted. He believes a further sum of up to £10bn may be required for the associated energy conversion equipment”

            If a projected 20GW (nameplate) of Round 3 UK off-shore wind was all storage-integrated instead, you could have 100GWh for little additional cost by 2020. Once you have the production lines in place, they get cheaper. The costs of installation and O&M are much lower too.

            Estimated costs for orthodox UK off-shore wind farms is £1bn/GW, plus £3bn for jack-up barges, plus a £1bn interconnector to Norway.

            My design UTILIZES superstructure that already exists just to support the turbine. It simply reshapes it into something much more useful, productive and efficient. There is no “platform” – the WEC provides stability. The sub-sea cylindrical vessel houses the accumulator.

            “It remains to be seen whether adiabatic compressed air energy storage will be viable, and whether Energy Bags are the right way forward. But without someone thinking outside the box, the concept of AA-CAES is likely to remain firmly on the drawing board.”

            “Relative densities” are as you describe. It’s just that there’s no energy storage potential in it.

            “Breaking through the denial is tough.” Sad but true. So many people stubbornly refuse to change their minds – they are not open to reason. Try to tell them that mankind created gods and they see it as an insult. Investors are called philanthropists if they don’t seek a profit.

            I showed a proof-of-concept model to the Chief Designer, Dynamics at a world class motorsport company. (WRC & F1) He e-mailed me after the meeting; “I believe the only reason the model behaves the way it does is because the suspension is topped out.” Demonstrably, that is not the case, but denial seeks comfort from discomfirmation bias. He saw the idea as an ‘insult’ to his professional pride.

            Stable Suspension and the WEC work on the same principle.

          • Cris Pond

            Exactly right! There is no difference in potential energy between kgs raised a meter, regardless of the composition. Why is this not relevant to the comparison of potential energy in gravity storage systems of different composition? o_O

            Of course gravity is acting on an underwater CAES system! What do you think is pulling the water down on the bag? There is raised water in such a system in a very meaningful sense. You raise the entire ocean a tiny bit when you inflate the bladder. The system then behaves as if you had a column of water above the bag and you raised it by the volume of the bag. I thought we already went over this…

            If you use a non-compressible fluid with a lower density than seawater, you eliminate the heat created by compression and make the system more efficient. I thought we already went over this too…

            The ocean doesn’t care whether the fluid is air or oil or alcohol, if the density is lower, it’s going to force it to the surface regardless. I think you’re confusing phase differential and density differential.

            Maybe your design does outperform underwater CAES, but I wouldn’t know because you haven’t described it. What is a WEC? Is your system floating? Is it anchored to the seabed in a rigid tower? How does it function?

          • Dave2020

            “Why is this not relevant to [different] gravity storage systems?”

            Because one is a gravity store and the other is a CAES.

            “we already went over this…” You go over this and just keep repeating the same misconceptions. Ask your physics teacher. You need to understand why what you’re saying is wrong.

            “eliminate the heat created by compression” = No compression = No energy stored in the bag. It isn’t CAES. It can’t work. The fluid in the tube used to fill the bag has the same ‘head’ as the sea around it. Ergo, no potential. It isn’t a gravity store either.

            “force” it to the surface! How much energy do you see in that “force”? It has no energy storage potential.

            WEC = wave energy converter. My design has four buoyant floats, but not in a rectangular pattern like a car’s wheels. My philosophy is – why harvest the wind and not capture the wave power? It’s there for the taking.

            “you haven’t described it.” Actually I have, but how much detail should I disclose on a public forum? I can’t afford the cost of Intellectual Property Rights. Patents (there are several) would cost a fortune. In my experience the whole system is unworkable and can descend into farce. e.g:-

            An examiner at the European Patent Office objected to Claim 1 on the basis, that – “there was insufficient information for someone ‘skilled in the art’ to make the bike suspension design.” The USPTO tried to reject the same patent because it was “obvious”, in light of some prior art. It wasn’t. The examiner misinterpreted the prior art drawing!! After a lot more expense the patent was granted.

            Can you get your head around the idea that no vehicle has to have a ride/handling compromise? A pure active suspension (i.e. no springs) can in theory give you compliant suspension with zero roll, but it is hideously complex and consumes hydraulic power. My passive car suspension does a better job and would cost no more than the orthodox ‘all-round-independent’ industry standard that is inherently, incurably, unstable.

            It sounds ridiculous I know, but that means that no automotive engineer on the planet has a truly comprehensive understanding of vehicle dynamics.

            My apologies for wandering off topic.

          • Cris Pond

            Who’s to say I’m not a physics teacher? ;p

            Underwater CAES is partially pressure-driven and partially gravity-driven. You start with an empty bladder and end with a full one, right? Where did the seawater go that used to be occupy that space? If it isn’t being lifted, where does it go?

            Did you try the oil and vinegar experiment yet? It’s probably something you should try if you want to understand fluid density.

          • Dave2020

            If that were actually the case, I’d have some concern for your pupils. If you don’t believe me, try to explain your ideas to Seamus Garvey, professor of dynamics at Nottingham University. He would be dismissive, I can assure you.

            “What do you think is pulling the water down on the bag?”

            There is nothing “pulling the water DOWN” on the bag! The force of gravity creates water pressure that acts uniformly in ALL directions. The bag has a MUCH lower density than the water, but that has no function in energy storage. If it wasn’t anchored to the sea bed it would shoot up and burst as the water PRESSURE diminished.

            If you read the ‘Engineer’ article, it is clear that the primary aim of the Energy Bag is to deal with the heat – right?

            The reasons it is under 600m of seawater are secondary:

            1. A pressure vessel at the surface is more expensive.

            2. It gives you a CONSTANT output pressure.

            “No matter how full or empty your container is, the pressure stays the same”

            “If it isn’t being lifted ..” It certainly isn’t “being lifted”, it is being displaced.

            If you fill the bag up so it is 20 metres in diameter at the surface and pull it down 600m, pumping air in to match the increasing water pressure, the water is displaced when you first submerge it and that won’t change at 600m.

            If you fill the bag with any incompressible liquid, as you suggest, you can’t pump any more in, even at 600m. It isn’t storing any energy, it can’t possibly work, as Professor Garvey would tell you.

            “At times of high electrical demand, air is drawn back from the store, heated and then supplied to a modified gas turbine.”

            Without using any gas, I hope?!

            PS: As an old guy, I don’t know what these emoticons mean (;p o_O) and can’t be bothered to find out.

          • Cris Pond

            Where is the water that is displaced in an underwater CAES system being displaced to?

            Did you do the oil and vinegar experiment yet? If obstinance isn’t keeping the vinegar at the bottom of the container, and relative density isn’t keeping the vinegar at the bottom of the container, why isn’t it mixing with the oil?

          • Dave2020

            I posted the answer over a day ago. – “Relative densities” are as you describe. It’s just that there’s no energy storage potential in it. Why do you keep repeating the same errors?

            Be serious Cris – anything put in the ocean displaces water around the globe. Liquids find their own level. Oh damn, sea levels are already rising!! We’d better not deploy a load of marine renewables!!

            Read back through my posts. All the answers are there. I must sign off now. I’ve got to write a long ‘response to the call for evidence’ on the “Innovation Strategy for Wales” before the end of next week. My brain aches! Good luck.

          • Cris Pond

            Good! If you understand fluids with lower densities rise above fluids with higher densities, why would you think oil wouldn’t be forced out of an underwater bladder… like it was in the Deepwater Horizon disaster?

            Liquids do find their own level, correct! Is the water level higher, lower or the same after the bladder is inflated?

            I thought of an example that might help you understand how underwater CAES functions: It would be like lifting a suspended weight with a spring. You can compress the spring and store energy until it reaches a certain threshold where the weight is lifted. Then, part of the energy is stored in the spring and part is stored in the raised weight.

            Do you understand now?

            If you are worried about marine renewables raising sealevels any measurable amount, perhaps you don’t understand how large the oceans are…

          • Dave2020

            The fact of the matter is, we’ve both made mistakes, but I’m keen to admit to mine:-

            I was wrong to say “ALL the stored energy comes from the displacement of water.”

            What a dummy! Of course, ALL the stored energy comes from the compression of air.

            It’s amazing how many times you can proof-read something and not question what you’ve written!?!?!

            Now it’s your turn to come clean Cris, but I have to be thinking of other things right now, so no more posts on this thread.

          • Cris Pond

            Come clean about what? o_O

            (That symbol means something akin to “are you serious?”, BTW)

            All the stored energy in an underwater CAES system does not come from the compression of air. Part of it is stored in the raising of ocean water. If the water isn’t being raised, where is it going when the bag’s inflated?

            To give you an illustration of why this wouldn’t cause coastal flooding of any kind: The surface area of the ocean is 3.61 x 10^14 m^2. The volume of the bag suggested in this article (not the one pictured) is 4.19*10^3 m^3:

            http://www.ecogeek.org/component/content/article/3522-energy-bag-offers-new-storage-for-wind-power

            (That would be 20m diameter, 10m radius => 10^3*3.1415*4/3 for the volume of a sphere)

            If you spread this out over the surface of the ocean, it would increase ocean levels by 1.16×10^-11 meters. That’s something like one one-hundred billionth of a meter.

            If you created 2,142,857 such bags, you could buffer the entire world’s energy consumption for 10 hours and still only raise the sealevel by 0.00002 meters if they were all inflated simultaneously.

            Do you see now why sealevel rise from marine renewables is nothing to worry about? The far greater danger (and the far more probable danger) is ice cap meltdown.

          • Dave2020

            “Come clean about what?”

            I made one silly mistake and corrected it.

            You’ve made three ludicrous mistakes and just keep stubbornly repeating them. If you can’t see the errors in your ‘physics’ I can’t help you. Ask professor Garvey.

            It’s hilarious you can’t see that I was joking – to try to get you to think about the fanciful nonsense of saying – “stored in the raising of ocean water.”

            Now you have illustrated that fact for yourself. The water displaced is a tiny volume and the water PRESSURE on the bag remains the SAME.

            “one-hundred billionth of a meter.” So now QUANTIFY how much energy is supposedly ‘stored’ by “raising water” by that much!

            Then quantify how much ENERGY can be extracted from a differential in liquid densities.

            Then EXPLAIN how much energy can be stored in a bag-full of incompressible liquid – next to nothing.

            I give up. Your obstinacy is the antithesis of scientific method.

          • Cris Pond

            Riiight… I think the antithesis of the scientific method is asserting that something is true because you say it is.

            You claim oil would not be forced out of an underwater bladder even when you can see it being forced out of an underwater bladder here:

            http://youtu.be/aV0Bmvuc_5U

            You claim relative densities have nothing to do with how liquids orient themselves even though you can see them orienting themselves based on relative density here:

            http://www.thegreenhead.com/imgs/salad-sunrise-oil-vinegar-1.jpg

            You seem to be suggesting 1.16×10^-11 meters is a measure of volume, when you actually need two additional dimensions for it to be a measure of volume, and when I’ve already given you the volume of water displaced! … that would be 4190 cubic meters, FYI.

            You aren’t extracting energy from a differential in liquid densities, you’re extracting energy from the movement of water to a lower potential from a higher one.

            If you were to place the bag in question at the deepest point of the ocean, you’d be displacing 4,190,000kg of water 10,000m. The maximum energy stored in such a system is as follows:

            4,190,000kg * 9.8 m/s/s * 10,000 m = 410,620,000,000 joules / 3600 joules per watt-hour / 1,000,000 watt-hours per megawatt-hour = 114 megawatt-hours.

            … I would ask you to provide an alternate calculation if you think this is wrong, but if you don’t even understand that relative density dictates how fluids behave, you aren’t going to be able to do that. I would stress again that you should look at a container of vinegar and oil and figure out why the oil is always on top. The internet is there to help you if you get stuck. Once you understand that, then come back to me.

          • Dave2020

            “The antithesis of the scientific method is asserting that something is true because you say it is.” Exactly so, and I am NOT doing that – you ARE. Ask a third party to ‘adjudicate’.

            “You claim . . when you can see it being forced out of an underwater bladder here:” Don’t be ridiculous. The oil at Deepwater Horizon is at a higher PRESSURE than the water. If you put oil in the bag, as you suggest, it would be at the SAME pressure as the surrounding water. Ergo, there is nothing to “force” it out!!!!

            “You claim relative densities have nothing to do with how liquids orient themselves.” Really?!?! Refer all our readers to the quote where I made any such claim. Stop deceiving yourself.

            “4,190,000kg * 9.8 m/s/s * 10,000 m = 410,620,000,000 joules / 3600 joules per watt-hour / 1,000,000 watt-hours per megawatt-hour = 114 megawatt-hours.”

            Take that calculation to anyone on the planet AND describe the fantasy mechanism you propose to extract all that lovely energy. After they’ve fallen about laughing, they’ll impolitely show you the door. Naturally, in the real world, no-one would even give you the time of day, let alone any R&D funding.

            I do at least get to interviews with the (limited) protection of a confidentiality agreement.

            This is the last post. I sincerely wish you good luck, but you need to understand the laws of physics and not be afraid to lose face. Admit to your mistakes – you’ll feel all the better for it.

          • Cris Pond

            The oil in underwater deposits is probably under slightly more pressure than the water at the point where it comes out of the sea floor, because it’s deeper and because there may be some component of the rock that is adding more force to the top of it.

            … but if a differential in pressure were the only thing acting on it, the oil should just remain on the sea floor, right? Why isn’t it doing that? Why should oil in a glass of water be forced to the top but oil in the ocean rest on the bottom?

          • Dave2020

            “. . . probably under SLIGHTLY more pressure than the water” What a bizarre guess! Why do you think there was a blowout then?

            “The pressure of the escaping oil, from a 21-inch diameter pipe, was last quoted by British Petroleum at 30,000 psi (2,041 atm).”

            “Water pressure at 5,000 foot depth is 2,617 psi (178 atm).”

            If the oil field (six miles down) was only liquid, it would at best only seep out slowly. The pressure comes from methane gas, trapped with the oil. You could call it a compressed gas energy store. All too often that gas is just flared off.

            Once the pressure’s gone, the oil rises SLOWLY to the surface.

            Does that make sense to you now?

          • Cris Pond

            You are probably correct that there was pressure on the oil from trapped methane, but if you understand that the relative densities cause the oil to rise to the surface, why would you think oil trapped in a bladder would not also rise to the surface? o_O

          • http://cleantechnica.com/ Zachary Shahan

            nice line, like that: “True sceptics are just as critical of their own understanding of a subject as that of the people with opposing views. A phoney sceptic (and a phony skeptic) forms his or her argument around confirmation bias and/or disconfirmation bias. “

          • http://cleantechnica.com/ Zachary Shahan

            i think the confusion here is that you are referring to what is need in the long run (to get to 100% renewables) and Bob is talking about right now. right now (and for quite awhile — we’ve got a ways until renewable penetration is a problem) we’ve got cheap wind and increasingly cheap solar (and other renewables, of course).

            for storage, we’re keeping our eye on a handful of technologies that look very promising and are getting close to commercialization. hoping (sort of betting) that at least one of them will give us the 100% we need.

          • Cris Pond

            … but renewable penetration is already a problem. In California, we’ve built out a ton of peaker plants to stabilise the renewable component of our energy supply. All of this will have to be scrapped to get to negative carbon (unless we could feed them biogas instead of earthgas).

            Public perception is a huge part of making renewables work. If people see 97 bucks a megawatt-hour and build out a ton of windmills because of it, they are going to be super-pissed when it turns out that’s not the actual cost for 100% renewable power. If they see stopped windmills because there’s an oversupply of power, they are going to be super-pissed that we invested the money to build them but not in anything to use the power they create when it’s created.

            You have to be up-front with people about the end-game you’re pursuing and the cost to get there. Surprising people with hidden storage costs and infrastructure that’s immediately obsolete isn’t going to make anyone happy.

            It’s absolutely correct to say that the system can absorb more renewables right now without driving the cost up significantly, but everyone’s drunk on cheap generation and not paying attention to the bigger picture. Very few people are focused on storage because very few people realise how critical it is (outside of this forum, of course).

            I would say at bare minimum, we should set up rudimentary pyrolysis to absorb some of the excess energy that already exists in the system. That’s not pie-in-the-sky future tech stuff. That technology exists now. … and it would at least solve the optical problem with idled windmills…

          • Dave2020

            Spot on mate – it’s market mayhem.

            We already have the same problem in the UK. Even with a low penetration of wind there are times when their power can’t be used, so they have to be stopped. We have a market intervention to compensate the companies for this ‘curtailment’. So you get headlines in the papers screaming “Turbine owners paid £12m to turn off windfarms!” That is terrible PR.

            As you may know, wholesale prices go negative when the wind blows all across Europe. This is absolutely NOT a ‘good’ thing!

            Worse still, the Energy Bill which proposes reform of the electricity market, will present plans to Parliament in 2013 greatly increasing the level of new unabated gas plant. Part of this will be ‘peaking plant’ and the ‘capacity market’ to incentivise this is expected to bring about the £10,000/MWh UK wholesale price. There is nothing in the Bill to ‘incentivise’ energy storage!!!!!!

            The Aussie market is insane:-

            “During that day, which reached a peak of 44.3°C in Melbourne in mid afternoon, the wholesale electricity price never fell below $1,000/MWh. For nearly four hours, it hovered around the $10,000/MWh price. The way the National Electricity Market works means that every generator switched on at that time receives that price, even though it still only cost the brown coal generators around $4/MWh to shovel the coal into their power plants.”

            A UK analysis showed that, TO MEET climate targets, half of the gas plants expected in 2030 – £10bn worth – will be “stranded”, i.e. forced to switch off early.

            How can investors be directed to put their money where it’s needed, when the liberal-market lunatics have taken over the asylum?

          • Cris Pond

            Investors can be directed to put their money where it’s needed with a global carbon tax.

          • http://www.facebook.com/people/Thomas-Cheney/716830405 Thomas Cheney

            A danish researcher has looked as using reversible fuel cells for managing wind load variations. In germany combining wind hydrogen and CO2 to make methane is being assessed at 60% production efficiency+ 20% heat from the methanization reaction.

          • Cris Pond

            I’m a bit skeptical about using electrolysis to buffer energy chemically. From what I understand, electrolysis corrodes your electrodes unless they’re platinum, which can be a bit expensive… I like that you can store energy indefinitely though.

            It’s interesting to know they’ve been able to methanise hydrogen. It looks like there are engines in development that can use hydrogen directly, which seems like it would be an even better approach:

            http://cleantechnica.com/2012/12/05/new-detonation-engine-could-slash-fuel-costs/

            If you use pyrolysis to create your hydrogen and methane, you have the added benefit of the carbon sequestration. You’d also have the option of exporting your chemical energy instead of using it to buffer.

  • http://twitter.com/tamikenn57 Tami Kennedy

    Viable carbon capture as IEA report bets major part of CO2 control in latest report?

    • crispond

      I’m not very hopeful about the feasibility of CO2 storage. If you pump it all underground, I’m not sure the likelihood of it staying there for any length of time is very high.

      If you have carbon in the form of pure graphite, on the other hand, it should just stay in the ground, or if it appears it’s oxidising too much, it can be put in the ocean in deposition zones.

  • Sean

    Biochar is stupidly easy to make, simply get a metal container that is almost airtight. Create a small hole in in that you can seal, fill with with carbon containing material. Put the container into a fire with the hole unblocked, the heat will force a flammable gas off, and in a short amount of time you will have charcoal, seal the container, remove from heat and allow to cool. tada!

    Things to watch for:
    make sure the flammable gas is burning (else the carbon capture process is somewhat reversed)
    make sure that oxygen can not get into the metal container after you remove it from heat.

    • crispond

      Exactly! You’re not actually reversing the carbon capture process if you don’t burn off the flammable gas, but you may be poisoning yourself. One of the things produced is carbon monoxide, which really should be burned off.

      That’s one of the reasons I prefer larger, industrial facilities for this process to having people do it in their backyards. It would allow you to capture the biogas too.

  • Nicholas Brown

    Thank you. I am looking into biochar. :)

    • crispond

      For home production, Peter Hirsch seems to know what he’s doing. There are plenty of designs out there which will smoke you out, and not in a good way… His is pretty clean:

      http://youtu.be/RXMUmby8PpU

  • geoffderuiter

    There are so many options out there for sure, cost of production and consumers willingness to pay extra is a major hindrance. We need to have fossil fuels pay for the pollution and climate costs and it will then make even more renrewables cost effective. Political will is a key factor as well.

    I hope for the best though!

    • crispond

      Hey, Mr. Obama at least mentioned climate change today, even if he’s confusing “removing carbon from the atmosphere” and just adding slightly less carbon to the atmosphere.

      California started their cap and trade auction today. I hope the chamber of commerce isn’t able to derail it. I would prefer a carbon tax, but at least this is a step in the right direction.

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