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Bad Coal Bad Coal Bad Coal

Helios
Ok best start this post , with a guilty secret .... I have benefitted from the burning of fossil fuels , as its pretty much powered most of the economy for the last 100yrs and in coals case at least at least 200yrs , and using coal and when steel hulls were invented , stopped complete deforistation , not that the big trees didnt still get cleared , but thats another story.

The rate of coal plant closures , is very welcome news , most air drafted systems spew out tonnes and tonnes ........ and tonnes of CO2, SO2 and NO2  and in some places the ash has become a toxic problem , that just sits there. somthing like 40% of the worlds energy comes from coal fired power generation , they have made some KJ to KW efficiency improvements , but its so cheap , however with the enviromental arguments having more say those financials that support coal with the slogan "yeah its just a cheap way" now have the banksy wordsmith treatment to transform the slogan into "yeah its just a  cheap way to destroy the biosphere"

somthing like 76,116 coal plants are in operation and surprisingly 1063 new ones are in the pipeline , the ones that are being closed are what are termed end of life , but shhh some of them were really inefficient , i mean really bad , current world record holder for conversion of KJ energy of coal into KW energy electricity , is a plant in Germany opened in 2012 achieveing 43% conversion of energy, the rest of the plants in operation through the world operate below 38% efficiency. Given new gas turbines are achieving 60% conversion of fuel KJ into KW , air drafted coal fired power will be on thinner foundations , and the financials promoting new coal power (and China and India are now the main countries still thinking coal is really great)  , will gradually become under increasing legal challenges and public profile . I know the fossil fuel buisness has made us all rich , but its not just a bit of wheeze anymore for financial borus stat porn , and its borderless , effects from big coal projects could be felt 100s, 1000s of miles away .


On the bright side noting that a mining sub has been lost at great depth ,hoping to start mining the cobalt , that poor battery tech is needing heres my round up of whats in the running , caveat (seek engineering advice before any investment decisions , disclaimer .... are 

ESSinc have won a contract for there ferrous ion flow battery , it gets around the rare earth flow battery materials , and has no loss of charge over 20000 cycle charges , and whats left over is a sort of ferrous oxide solution , so looks good to me .


energy storage:mmm well a bit of future fight brewing , given green hydrogen is finding its production method , then efficiency and losses are starting to have real power in energy systems discussions , yeah all those engineers who loved the efficiency calculations (but never got promoted) are in vogue now , as we now want very energy expensive green hydrogen, cables , length of cables , efficient transmission voltages , rectifier efficiencies ... its all getting in assements of efficiency and reliability and for some engineers who make really good stuff , its a new age .


Solar PV .... mmmm I still want an explantion of recycling route , not convinced for me yet , much better in some ways to plant crops or trees if you think in food miles terms , but not denying in some high solar parts of the world it is useful . Not heard any more about 20% power increase from graphene based archtecture yet either.


Nuclear energy as Hydrogen supply ?? mmmm your going to be using a lot of water and if your electrolyser doesnt like saline water (and most dont) your going to have a problem , the new time frame for old nuclear plants will be planned refuelling schedules, and should renewable tech win out then the world is going to have to think how all this 1000-5000 year high radioactive waste is going to be stored , and of course we are all still paying for nuclear plant failiures one way or another , just to decomission the current ageing uk fission fleet is £20bn , so its not exactly cheap energy.


solid Lion battery is claimed by Quantumscape but as yet its to break out of lab/bench demonstrator , and this may be more difficult than the crazy press briefing suggest , but offering at least a 10% increase in energy density , it changes the balance further to the electric car . I still dont think frieght/goods in EV works too well for some loads , as the wieght becomes an issue , noting a number of popular luxry end EVs are at 2200kg kerg weight , then when the stats come in on crash incidents , i think will not look too good 2200kg at 80mph will challenge most encap vehicle safety tests . So for me its still the smaller comfortable , smaller battery EV , that looks the most interesting , the big luxury cars will have to become lighter. and I would think car makers will have to recieve end of life vehicles to re cycle them . I do expect we shall see some tech failiures in cars and its risky thing if you build in poor tech , we still dont know what happens to batteries at 5yrs use , and given some makers are going for wrap around hi tech visual dashboards and quite high luxury electrical loads , electric seats etc , and the winter heating hasnt been fully worked through (it may just be a matter of learning new driving care regiemes) , a cold rainy winteres night is still somthing of a test for the EV . Hats off to VW for selecting a EV battery with good recyclability , and it may well be that car  makers should take note , if you install a rubbish battery or one that damages the enviroment , youll probebely lose investors money in the end .


Packaging  tech has had fits and starts , i guess some packaging makers are waiting for improved biomaterials , which are in the pipeline and BIOPac are well placed to have good market share , the big one to solve is perhaps glass , I personally would not like to see my french made preserving jars become contraband , but obviously things like water, wine and jams sauces are going to be in the spotlight , the transport miles are a bit of a distraction in that you have to make stuff somehere , and glass has some very useful properties you can wash it and re use it , but even so it has a high energy use in making it .Full recycling is certainly comming , I mean municipal incinerators arnt very good and burying things in the ground will always have some future pollution problem, and full recycling has some engineering challenges .


Sequential oxygen combustion is still looking good , and if it can burn the wastes effectively will offer real emissions cuts  but more about this tech in another session , as its bed time .
Parents
  • 0
    Decommissioning and disposal are also problems for Wind and Solar PV. I agree that nuclear waste is a nasty problem but it is  small problem. A typical 1GWe nuclear plant will contain around 100 tonnes of uranium in the core. When this is removed as spent fuel quite a lot of it can be reprocessed into new fuel. The highly radioactive parts decay the fastest (basic physics), which is why the rods are left in the spent fuel pool for a few years. The same principal is used when decommissioning the plant. Remove all the peripherals and leave the reactor to decay for 40 or better 70 years.

    You could drink the water from Fukushima without any problems from the radioactivity in the same way that you could drink the water from the outfall from a sewage treatment works, but would you? The human body is already radioactive, mostly due to natural Potassium 40 and Carbon 14.

    http://www.rerowland.com/BodyActivity.htm

    The release of the Fukushima water will be barely detectable amongst the other, natural, radioactive materials in seawater. There is almost enough Uranium in seawater to make commercial sense to ‘mine’ it using special filter systems.

    What do we do with life expired wind turbines? The metals can probably be recycled but you need to get a very big crane back on site to do so. The blade are currently a problem and are just landfill. There is then quite a few hundred tonnes of reinforced concrete as a base. What do we do with that? You could install a new wind turbine but it would have to be no bigger than the old one, which is probably no longer economical. Why no bigger? The base is designed to with stand a certain overturning moment. A larger, taller, turbine will exceed this. The separation of the turbines is designed to minimise ‘masking’. Bigger turbines require more separation.

    Sulphur Hexafluoride (SF6) is an interesting problem. It is actually rated between 23000 and 26000 times better as a greenhouse gas than CO2 depending on whose numbers you look at. The high number is mostly due to it’s stability and long life in the atmosphere. A lot of work has been done to minimise the loss from HV equipment and switch gear. The target is less than 0.5% per year. Alternatives are being developed both for SF6 insulated switchgear and different insulating systems. The general problem is that the alternatives require greater clearances and higher pressures increasing the CO2 footprint of the structure of the switchgear (thicker walled, heavier tanks, bigger insulators). The other problem with the SF6 alternative gasses is that they have a life span. Each spark or arc reduces their effectiveness whereas SF6 recombines to it’s original form. DILO are one of the experts on this as well as SF6.

    https://dilo.eu/en/alternative-gases


Reply
  • 0
    Decommissioning and disposal are also problems for Wind and Solar PV. I agree that nuclear waste is a nasty problem but it is  small problem. A typical 1GWe nuclear plant will contain around 100 tonnes of uranium in the core. When this is removed as spent fuel quite a lot of it can be reprocessed into new fuel. The highly radioactive parts decay the fastest (basic physics), which is why the rods are left in the spent fuel pool for a few years. The same principal is used when decommissioning the plant. Remove all the peripherals and leave the reactor to decay for 40 or better 70 years.

    You could drink the water from Fukushima without any problems from the radioactivity in the same way that you could drink the water from the outfall from a sewage treatment works, but would you? The human body is already radioactive, mostly due to natural Potassium 40 and Carbon 14.

    http://www.rerowland.com/BodyActivity.htm

    The release of the Fukushima water will be barely detectable amongst the other, natural, radioactive materials in seawater. There is almost enough Uranium in seawater to make commercial sense to ‘mine’ it using special filter systems.

    What do we do with life expired wind turbines? The metals can probably be recycled but you need to get a very big crane back on site to do so. The blade are currently a problem and are just landfill. There is then quite a few hundred tonnes of reinforced concrete as a base. What do we do with that? You could install a new wind turbine but it would have to be no bigger than the old one, which is probably no longer economical. Why no bigger? The base is designed to with stand a certain overturning moment. A larger, taller, turbine will exceed this. The separation of the turbines is designed to minimise ‘masking’. Bigger turbines require more separation.

    Sulphur Hexafluoride (SF6) is an interesting problem. It is actually rated between 23000 and 26000 times better as a greenhouse gas than CO2 depending on whose numbers you look at. The high number is mostly due to it’s stability and long life in the atmosphere. A lot of work has been done to minimise the loss from HV equipment and switch gear. The target is less than 0.5% per year. Alternatives are being developed both for SF6 insulated switchgear and different insulating systems. The general problem is that the alternatives require greater clearances and higher pressures increasing the CO2 footprint of the structure of the switchgear (thicker walled, heavier tanks, bigger insulators). The other problem with the SF6 alternative gasses is that they have a life span. Each spark or arc reduces their effectiveness whereas SF6 recombines to it’s original form. DILO are one of the experts on this as well as SF6.

    https://dilo.eu/en/alternative-gases


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