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Electricity

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  1. chdot
    Admin

    There have been various threads on here about electric cars and also Climate Change generally, this is today's development

    "

    "Our existing power stations are closing down and their replacements will be radically different as we de-carbonise supply to reduce emissions.

    "This represents an enormous challenge, but it leaves the UK uniquely placed to benefit from exciting innovations set to transform the global electricity market.

    "The UK can lead the world in harnessing these innovations. We do not call for new subsidies or significant public spending, but rather a level playing field through fairer regulation and a better managed network to allow these exciting new technologies to compete.

    "If we get this right, a Smart Power Revolution could save consumers £8bn a year."
    The commission wants to see more ideas for storing energy - like using liquid air or pumped hydro power.

    "

    http://www.bbc.co.uk/news/business-35722324

    Posted 9 years ago #

  2. chdot
    Admin

    Big in Scotland (maybe) -

    http://www.inverness-courier.co.uk/Home/New-Loch-Ness-hydro-scheme-would-be-Scotlands-biggest-5340959.htm

    Posted 9 years ago #

  3. crowriver
    Member

    US agency reaches 'holy grail' of battery storage sought by Elon Musk and Gates

    http://www.theguardian.com/environment/2016/mar/03/us-agency-says-has-beaten-elon-musk-gates-to-holy-grail-battery-storage

    Posted 9 years ago #

  4. jdanielp
    Member

    Half the price in half the time: solar storage innovation harnesses new energy frontier

    http://gu.com/p/4hvj7?CMP=Share_AndroidApp_Copy_to_clipboard

    Posted 9 years ago #

  5. Min
    Member

    it leaves the UK uniquely placed to benefit from exciting innovations set to transform the global electricity market.

    Haha! Brilliant marketing speak for "yer aw doomed".

    Posted 9 years ago #

  6. neddie
    Member

    Molten salt seems like a promising way to store large scale solar furnace electricity:

    http://www.bbc.com/news/business-34974644

    And not energy intensive to manufacture, unlike batteries and solar PV panels

    Posted 9 years ago #

  7. neddie
    Member

    Put the (large) renewable plant where it is most suited:

    - Hydro in the mountains.
    - Wind turbines in windy locations like Scotland and the North of England, and on the tops of hills & out at sea.
    - Tidal in estuaries and narrows.
    - Solar furnaces in the Moroccan and Portuguese deserts.

    Connect the whole lot up with massive interconnectors to share/buy/sell in times of plenty or need.

    Posted 9 years ago #

  8. steveo
    Member

    IMO PV is as much a dead end as oil. It will always have certain niche applications but I doubt it will play a significant part in the "answer"*. Chasing solar power in the UK is largely futile we lack the levels of solar radiation required to make them feasible even in the south, it gets much worse much quicker as you go north. Equally the distribution of the received energy doesn't match the demand through the year. One might manage to get decent amounts of power in the long summer days in Edinburgh but realistically you want the power through the short winter days. Storing electricity all year is clearly not going to fly.

    *unless we develop the microwave power plant from SimCity.

    Posted 9 years ago #

  9. crowriver
    Member

    Surely the best implementation for solar PV is micro generation at a domestic or local area level? Such as popping a few panels on south facing pitched roofs in most residential areas and feeding into the grid, thus bestowing a zero or negative energy bill for many households for much of the year?

    Offices, hotels, and other businesses with available roof area, could also cut their energy bills and reduce carbon footprint this way.

    It's actually fairly sunny (relatively speaking) on the east coast. Even when the sun is not shining directly solar panels can still generate electricity.

    Posted 9 years ago #

  10. I were right about that saddle
    Member

    http://www.inference.eng.cam.ac.uk/sustainable/book/tex/sewtha.pdf

    Posted 9 years ago #

  11. steveo
    Member

    Surely the best implementation for solar PV is micro generation at a domestic or local area level?

    Except you need enormous panels to generate modest amounts of power.

    In January you'd need 2 square m of south facing solar panel to collect 1kw of solar radiation, pv is only of the order of 20% efficient in turning that in to electricity, at mid day with efficiency dropping off a cliff either side of that time. For the 4 or 5 hours of generating time you'd be lucky to generate 2kwh of electricity. The costs of fitting that to every household would make be of the order of the gdp for a small country and wouldn't make a dent in the power requirements.

    Best case, in June that same 2 sqm would be colleting ~4kw/h at mid day. You'd probably get 10-12 kw/h per day.

    faux edit: a nominal 2kw system requires 14 sqm of panel, costs £2-£3k and as above isn't really going to make much difference.

    Posted 9 years ago #

  12. Murun Buchstansangur
    Member

    I was surprise passed by an electric scooter the other day, it was extremely silent. Made me realise how much I depend on hearing vehicles approaching from behind.

    Posted 9 years ago #

  13. I were right about that saddle
    Member

    "I was surprise passed by an electric scooter"

    All electric vehicles should play the sound of iron-shod hooves on granite setts at a rate and volume appropriate to their speed.

    Posted 9 years ago #

  14. PS
    Member

    Whatever happened to micro-generation from turbines in the water supply infrastructure?

    Posted 9 years ago #

  15. steveo
    Member

    There is a nice little community project in Harlaw and I believe Scottish water generate a lot of power from redundant treatment facitlies converted to hydro, and something of the order of 50% of the power requirements at Glencorse are met by hydro. But I'm not sure robbing power (water pressure) from the water mains would be a great idea.

    Posted 9 years ago #

  16. Murun Buchstansangur
    Member

    "All electric vehicles should play the sound of iron-shod hooves on granite setts at a rate and volume appropriate to their speed."

    Indeed. God help us if Deliveroo go electric.

    Posted 9 years ago #

  17. neddie
    Member

    Whatever happened to micro-generation from turbines in the water supply infrastructure?

    Because the water supply is often pumped i.e. it consumes electricity. So it wouldn't make sense to try and generate electricity from it.

    And it's likely forbidden in the contract you have with the water supply company (sensibly). (It may even be illegal?)

    Posted 9 years ago #

  18. neddie
    Member

    Sorry, but IRWAT's book is just full of techno-bollocks and the propagation of many myths:

    Uranium can be used 60 times more efficiently in fast breeder reactors, which burn up all the uranium – both the 238U and the 235U (in contrast to the once-through reactors, which burn mainly 235U).

    Except that it takes around 30 years for a tiny percentage (not "all") of the 'unburnable' U238 to be converted to 'burnable' Plutonium, which then has to be extracted using an expensive, messy and dangerous process. Fast-breeders are a failed experiment, primarily designed to create Plutonium for nuclear weapons.

    What’s the cost of cleaning up nuclear power sites? The nuclear decommissioning authority has an annual budget of £2 billion for the next 25 years.

    More like £100 billion and counting.

    And the book fails to take account of many social aspects. E.g. Although plane travel may be more energy efficient than a single occupancy car per passenger, (cheap) plane travel creates new journeys that weren't otherwise possible - like Stag weekends to Barcelona for example.

    I could go on picking holes in the book, but that would be a whole new book in itself.

    Posted 9 years ago #

  19. wingpig
    Member

    As gravity is always-on it makes some sense to co-opt it into part of a storage battery which can be charged and discharged anytime, but using water as the moveable mass must be quite lossy and it's not ideal for localised use with small energies. One of my things-do-do-when-I-get-my-home-laboratory is build a home energy system based around storage using the gravitational potential energy of a large rock on a wire, mechanically winched up by means of a pedal-driven device (or other exercise machines, so that it also helps the obesity crisis) and able to be discharged either by having the supporting wire drive a mechanical electrical generator (with plenty of gearing and flywheels for a smoothed scalable output) or possibly occasionally acting as the piston in a long vertical chamber to mechanically pump things, though a home system wouldn't have much volume. The available drop could have to be great enough to be able to allow vital systems like freezers to power themselves whilst on holiday when there was no-one to pedal. There could also be a last-resort option to gain height using electrical power, preferably during times of excess from other renewable generation sources. Heat losses from the conversion steps could be captured; they mightn't be much, but could be enough to take the edge off ground-temperature water for hand/dish-washing etc. Ideally the house into which this is fitted would be optimally-built to not require much heating, to be able to use a forced air pressure differential across it to ventilate it and would have things like fridges which create waste heat next to things which need to be heated-up, like hot water tanks. You'd also need much less heating in a house if you needed to spend a couple of hours every day pedalling fairly hard to pull up your big rock on a wire.

    Posted 9 years ago #

  20. crowriver
    Member

    Whereas affordable cars and cheap petrol/diesel create journeys that were not otherwise possible too...

    Posted 9 years ago #

  21. cb
    Member

    "gravitational potential energy of a large rock on a wire"

    I'm sure Professor Pivot in A to B Magazine discussed such a system (although it may just have been a mini pumped storage system attached to the side of a house). I can't really remember what his conclusions were - probably that it wouldn't be up to much given any reasonable drop height constraints.

    Posted 9 years ago #

  22. jonty
    Member

    The rock thing sounds fun but I'm not sure it's practical: I'm always surprised by how little energy raising water/solids up to great heights actually stores. For example, I might have my sums wrong but I think raising a half-tonne rock up 10m (which is probably the extreme limit of what you could get away with in a residential garden without upsetting the neighbours) would store (up to) 50 kilojoules, whereas the daily energy consumption of a freezer is measured in the megajoules. There's a burning stuff for energy is so popular - coal/oil/gas actually store really quite huge amounts of energy for their size.

    Posted 9 years ago #

  23. cb
    Member

    http://www.scottishenergynews.com/scottish-power-may-double-size-of-cruachan-hydro-power-scheme-if-the-uk-govt-price-is-right/

    The article talks of 400 - 600MW of additional capacity, although I'm not sure if that's the right word to use?

    An additional turbine hall seems to be a given (so extra power output) but additional dam construction is a "possibility" (but surely a requirement to add capacity?)

    Posted 9 years ago #

  24. steveo
    Member

    The rock thing sounds fun but I'm not sure it's practical:

    Its funny I've just done the same maths. Kind of. My fat self at the top of a 23 meter drop has less than 6wh of potential energy yet the power required to get me up a said ramp on the bike is more like 10wh.

    I'm guessing going much slower up the ramp reducing the air resistance would have brought that right down.

    Posted 9 years ago #

  25. cb
    Member

    The rock thing

    https://www.gravitricity.com/

    It doesn't look like they've actually built anything.

    "The key requirement is a deep hole in the ground; it could be a disused mineshaft brought back into use, or it could be a purpose drilled or sunk shaft. Depth requirement is typically 500 to 1,500m"

    Hmm, I suppose I could start excavating under the cellar.

    Posted 9 years ago #

  26. wingpig
    Member

    "...any reasonable drop height constraints..."

    Definitely not with water, but large rocks are denser than water, though even a well-insulated naturally-lit houseful of keen cyclists who didn't waste any energy output with things like commutes to work/rides outside and who only took cold showers after sitting and generating a few hundred Watts for a couple of hours every day wouldn't make much of a dent in the mean UK daily domestic electricity consumption (12½kWh?) but you might be able to run low-consumption luxury items relatively guiltlessly.

    Posted 9 years ago #

  27. steveo
    Member

    (12½kWh?)

    I read more like 4kwh but even that would be a pretty difficult to generate on bike, and probably hideously inefficient. You'd probably be better throwing the pasta straight into a furnace and using the resulting heat to run a Stirling engine.

    Posted 9 years ago #

  28. jonty
    Member

    I think you might be better off burning (or anaerobically digesting) the food you were going to give them!

    Posted 9 years ago #

  29. wingpig
    Member

    "My fat self at the top of a 23 meter drop has less than 6wh of potential energy yet the power required to get me up a said ramp on the bike is more like 10wh."

    Wonder if it would be more efficient to crouch inside a barrel and have someone roll you up?

    Posted 9 years ago #

  30. crowriver
    Member

    125kW per day per capita according to IWRAT's book. Though that's a (rough) average. If you drive a car, your energy consumption goes up MASSIVELY. Whereas saintly cyclists have even lower energy consumption than pedestrians, it would appear.

    So the drivists are right: we are smug bar stewards.

    Posted 9 years ago #

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