Britain's Largest Battery Is Actually A Lake

  • Published on Nov 5, 2018
  • Dinorwig Power Station, otherwise known as Electric Mountain, is a pumped-storage hydro station in Llanberis, Wales. And yes: it's Britain's largest battery. Here's how it works, and why some of the things you think you know about TV pickups might not be so true any more.
    Thanks to all the Engie team! More about them:
    Public tours of Electric Mountain are closed until mid-2019, but you can find details here:
    Camera op: Ryan Priestnall
    Editor: Michelle Martin (@mrsmmartin)
    I'm at
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    and on Instagram as tomscottgo

Comments • 1 540

  • Reckless Roges
    Reckless Roges 5 days ago

    I'm wondering if we have Grady@Practical_Engineering to thank for ramming the term "water hammer" back into the collective consciousness?

  • callum hardy
    callum hardy 5 days ago

    A battery that will never get chemically exhausted, like electric batteries. Genius.

  • robert kennion
    robert kennion 5 days ago

    so it loses energy everynight..buts that cool because it saves money

  • Paul Bell
    Paul Bell 9 days ago

    Officer Dibble. Ha.

  • QVJIPN - 42
    QVJIPN - 42 11 days ago

    Ever heard of Tryweryn?

  • Seba Zabala
    Seba Zabala 13 days ago

    2:43 that's a great sample

  • QueenAshe
    QueenAshe 14 days ago

    Hey, I've been here! I live around the corner, in Bangor. Should've popped over :P

  • ChickenDippers
    ChickenDippers 21 day ago

    fantastic video

  • Raine Villa
    Raine Villa 22 days ago

    Thomas Scott is simply the best.

  • greggv8
    greggv8 23 days ago

    How much 'free' power do they pick up from rainfall into the upper lake and flowing into it from rain on the land around it?

  • Neki
    Neki 25 days ago

    your channel needs a cool name

  • Human Bean
    Human Bean 26 days ago

    such a shame that were destroying the precious environment to create dangerous chemical battery products

  • Abhijeet Kumar Thakur
    Abhijeet Kumar Thakur 26 days ago +1

    In monetary terms, it might be beneficial but as far as the conservation of energy principle is concerned, it's an absolutely useless exercise.

  • Original Wolf
    Original Wolf 28 days ago

    Bond villain Lair anyone?

  • Szabó Arthur
    Szabó Arthur 29 days ago

    Can it generate 1.21 gigawatts of power? I just need it... Uhm... For no particular reason.

  • Leonardo Freitas
    Leonardo Freitas 29 days ago +1

    What is a swimming pool in litters? I don't know the imperial system

  • natskis
    natskis Month ago

    If we're talking PE, would it not technically be all the forests?

  • natskis
    natskis Month ago

    If we're talking PE, would it not technically be all the forests?

  • XIX 5 Gamers XIX
    XIX 5 Gamers XIX Month ago

    I live right down the street from this place

  • Patrick Henderson
    Patrick Henderson Month ago

    God I love Tom

  • TheFrenchMansControl

    If it rains lightly at the top, is that a trickle charge?

  • B A
    B A Month ago


  • BlackJudgeJudy
    BlackJudgeJudy Month ago

    50HZ LUL

  • WelshGaming
    WelshGaming Month ago

    "... rainy bit of Wales" That doesn't help

  • Sam _
    Sam _ Month ago +1

    I went here just over a decade ago on a school trip. It was so awesome.

  • nzoomed
    nzoomed Month ago

    This power station is almost identical to the Lake Manopuri Power station here in New Zealand!

  • Carl Klinkenborg
    Carl Klinkenborg Month ago

    It's Wales. It's raining. Comforting to know some things never change...

  • oxamymorrisxo
    oxamymorrisxo Month ago

    I’m so sure I went here on a school trip once, I’d completely forgotten

  • John King'ori
    John King'ori Month ago


  • Treblaine
    Treblaine Month ago

    So are you saying this is capable of outputting ONE POINT TWENTY ONE GIGAWATTS!

  • Awntry
    Awntry 2 months ago

    Thank you, Tom! I watched this video just a week before my Advanced Human Geography paper for CIE A Level and one of the questions I was given in that paper was: "‘Producing energy from renewable resources is not the answer to meeting energy demand.’ How far do you agree?". I mentioned this lake as one of the case studies to support my argument. I got an A grade in Geography and I got my best mark from this paper.

  • AEC
    AEC 2 months ago

    It is spelt dinorwic not dinorwig. Just saying

  • HarleyAMV
    HarleyAMV 2 months ago

    Seeing that massive lever lifting as if weightless honestly gave me chills

  • PsychoLucario
    PsychoLucario 2 months ago

    Those giant counterweights on the valves are actually interesting, you'd think with hydraulics you wouldn't bother but no, it must make it easier to close or maybe acts as a fail safe to close the valve if power fails

  • Markus Werner
    Markus Werner 2 months ago

    Solarpower or Windpower should be used to charge the battery and if they are not available it should be discharged. It does not make sense to charge it in the night, just because price is low.

  • Kenneth Hoang
    Kenneth Hoang 3 months ago

    Battery 2: Electric Boogaloo

  • annoloki
    annoloki 3 months ago

    Ohhh the steps! I remember so many times driving past the quarry when I was a kid and noticing this mountain with giant stairs calved into them... was always amazed by the sight, had no idea it was this... awesome!

  • Nola Gatto
    Nola Gatto 3 months ago

    We ❤ electric mountain

  • Nick Way
    Nick Way 3 months ago

    Anyone know the efficiency of the system? Between pumping the water up, then regaining a percentage of the energy spent as it comes back down.

  • nick4819
    nick4819 3 months ago

    So you generate power...and then you use the same amount of power, if not more, later on to pump the water back up? I'm leaning towards more energy use to pump it back just because you aren't collecting 100% of the energy when it's falling.

  • Logan
    Logan 3 months ago

    water + electricity = good, but bad

  • Mudkip909
    Mudkip909 3 months ago

    0:33 Why is it called dino cam

  • MrcabooseVG
    MrcabooseVG 3 months ago

    This lake in the rainy bit of Wales? Doesn't really narrow it down much

  • piltrid
    piltrid 3 months ago

    Put your tongue on it!

  • IliasHDZ
    IliasHDZ 3 months ago

    This company called ENGIE is powering my house and i live in Belgium.
    For us it's called Engie Electrabel and i know this company for a while.
    I didn't know it was in the UK as well.

  • Alex spander
    Alex spander 3 months ago

    1:26 thats enough to power a delorian!!

  • alex chamber
    alex chamber 4 months ago

    I was there when they turned it on, seeing the massive pistons moving was amazing!

  • Sam Sırri
    Sam Sırri 4 months ago

    I don't understand why is guy shifting the topic to talking about TV channels! That's very confusing.

  • Sam Seidel • 11 minutes ago

    Europe funds much cooler engineering than we do. The only problem that the US government seems to be willing to put money into creatively solving is killing people.

  • Pook365
    Pook365 4 months ago

    They really should make another one if these...
    Electric Mountain Too : Return of the Electric Boogaloo

  • Ignacio Pugliese
    Ignacio Pugliese 5 months ago

    that place is half life

  • rjc0234
    rjc0234 5 months ago

    so where does it get its power at night to pump the water back up? seems a bit backwards. why not just build a new power station to meed that extra daytime demand, and turn it off at night. defeats the purpose of not having enough capacity in the national grid if at night time that limited capacity is being used "recharge" a giant battery whose purpose is to take up the slack when it is needed.

  • John Dooley
    John Dooley 5 months ago

    Turlough Hill in Co. Wicklow, Ireland runs a similar system, known as a pumped storage system.

  • Matthew Tolentino
    Matthew Tolentino 5 months ago


  • Damp de Lux
    Damp de Lux 5 months ago

    We have a similar mountain in Luxembourg: The Niklosbierg (Nicholas Mountain).
    But I guess the Welsh one is bigger.

  • LALLAREN#1 !
    LALLAREN#1 ! 5 months ago

    very nice

  • d0nk0
    d0nk0 5 months ago

    Stupid prick in his health and safety gear while sitting in his office giving an interview.

  • Brian Cox
    Brian Cox 5 months ago +1

    Another excellent video... i'd never heard of power stations like this before (well, i'd heard of hydroelectric, but never where it pumps it back up at night)

  • Pav Litt
    Pav Litt 5 months ago

    Things like this used to be on TV.

  • max nye
    max nye 6 months ago

    Iceland's battery is Iceland

  • benjaminismyname
    benjaminismyname 6 months ago

    Do you work at Nottingham University?

  • Wendel Bolide
    Wendel Bolide 6 months ago

    3:25 NO DANCING

  • Omar Omar
    Omar Omar 6 months ago

    One of my favourite channel on TVclip. Thank you

  • Steven McGuinness
    Steven McGuinness 6 months ago

    Went there on a school trip in the 90’s!

  • James Samways
    James Samways 6 months ago


  • GMT {FS}
    GMT {FS} 6 months ago

    So they create energy then use more energy than they made to get it back up the mountain? So they lose energy every time it turns on

  • Clarence Trumble-Lovegod

    It must be very energy intensive to pump the water back to the top again. Cheaper, sure, but the amount of energy needed must surpass by some margin the energy produced.

  • Javier Reyna
    Javier Reyna 6 months ago

    Really? So can be this considered a perpetual energy machine? Because it supllies itself again with pumpig up the water

  • Vince mckaine
    Vince mckaine 6 months ago

    The Mark Rober of UK

  • Unequal
    Unequal 6 months ago

    0:38 Who else thought this looked like a Bungie hat

  • BrutalTurtle
    BrutalTurtle 6 months ago

    what happens to the fish in the reservoir? they're just passed back and forth?

  • Ryan Priestnall
    Ryan Priestnall 6 months ago

    Was a fun day working with you Tom! Great edit too.

  • Pawcket
    Pawcket 6 months ago

    Whoa, really cool stuff. Thanks for your work, Tom!!

  • Janita G
    Janita G 6 months ago

    This makes my little engineering heart explode. So cool. I've been at a water treatment plant when a valve shut too fast - water hammer is intense!

  • Tyee Cambrón
    Tyee Cambrón 6 months ago

    In Seattle we just call it a dam. We have a good one in Washington state that powers Seattle.

  • InvadersDie
    InvadersDie 6 months ago


  • Roc Aràjol
    Roc Aràjol 6 months ago

    that's bonkers

  • that-nerdy-hufflepuff
    that-nerdy-hufflepuff 6 months ago

    I went there with my family a few years ago. It was very interesting, but I felt quite sick because the roads to get there are very twisty.

  • Nighthawk
    Nighthawk 6 months ago

    the setup of exposed piping and heavy machinery, and crude mountain rock, reminds me a bit of TF2 and it's level design.
    you know, circa 1970's technology, underground bunkers, missile silos, turbines and control rooms..... hell, you even have Engies

  • DK Surname
    DK Surname 6 months ago

    It's scary knowing that whole nations sit in front of TVs for decades now, getting brainwashed together, being fed censored and moderated content.

  • ChancelorPalpetine
    ChancelorPalpetine 6 months ago

    I actually went here a while back during a storm and the mountain got struck by lightning. It broke all the electrics, including the theatre they show movies about the mountain in. Basically everyone in the room had to try and cover their ears whilst the speakers blared out a high pitch tone on full volume.

  • Matt Helton
    Matt Helton 6 months ago

    Your videos are by far some of the best on TVclip. I'm so happy to see your views and subscriptions continue to increase. Keep making videos, please!

  • Sledanet
    Sledanet 6 months ago

    Didn’t you make a video about a weight inside of a deep well that would be lifted by solar and wind energy via an electric motor and then dropped controllably to give off power again? That’s one of my favorite ‘simple ideas’ for a sustainable future ever!

  • Ferble-kun Sakrrislin
    Ferble-kun Sakrrislin 6 months ago +1

    Very impressive.

  • Cj Iscool
    Cj Iscool 6 months ago

    I thought the salt in the water could make a battery or something

  • Cj Iscool
    Cj Iscool 6 months ago

    Looks very expensive

  • The Ethicist Philosophy Show

    10-30 seconds?!?!

  • Kaleb Bruwer
    Kaleb Bruwer 6 months ago

    This is really cool, but you would need a lot more to balance a fully renewable grid. It's easier to go nuclear, that shouldn't be much harder to balance than coal. Take Germany and France as examples of both approaches.

  • James Mead
    James Mead 6 months ago

    How efficient is it?

  • wolfedog99
    wolfedog99 6 months ago

    Grand Coulee dam in Washington does some of this with Banks lake. Though there are three levels plus some irrigation going on, the Columbia river at the foot of the dam, Roosevelt Lake behind the dam(about 400 feet), and Banks Lake on the plateau above(add another 280 feet). The maximum height of Lake Roosevelt is the elevation of the river at the Canadian USA border 151miles upstream. Some years after Grand Coulee was originally built two dams were built upstream in Canada to help regulate the seasonal flow variations, under a bargain that provides British Columbia electricity as payment for the dams.
    Anyway, when the spring-summer flows are high and electricity demand is relatively low excess power is used to pump water up to Banks lake from Roosevelt Lake, and a large fraction of the water in Banks lake is used for irrigation so there are 6 pumps plus 6 pump-generators about 50Mw each(600Mw for pumping and 300Mw generating), pumping capacity is 600cubic meters per second(45-55per unit).
    The main dam has a total capacity of 6.8Gw and the 3 largest turbines are 805Mw each, 3 more at 600Mw, the original 18 at 125Mw each and the 10Mw service generator. The total power capability from the dams in this river basin is 29Gw.

  • Karl Black
    Karl Black 6 months ago

    I have been on one of the public tours at this power station. There is two railways in the town beside it, and National Slate Museum is beside it as well. The ticket office for the public tours is in the town of Llanberis

  • mumiemonstret
    mumiemonstret 6 months ago

    Nice to have a battery that trickle charges itself in the typical Welsh weather!

  • Pseudo Nym
    Pseudo Nym 6 months ago

    Ba Dum tss
    😩I feel the groans 😦

  • Dr Moriarty
    Dr Moriarty 6 months ago

    You call THAT large? I think not...

  • Aman Haman
    Aman Haman 6 months ago

    I really thought it was gonna be a lake with enormous quantities of an electrolytes dissolved in and separated by a semipermeable membrane.

  • Miles Davenport
    Miles Davenport 6 months ago

    Excellent and informative. Thank you.

  • haiironezumi
    haiironezumi 6 months ago

    I can see a great potential for this as storage for solar, with the solar power feeding the grid as required, but also powering the pumps to store the gravitational energy.

  • James Berend
    James Berend 6 months ago

    Isn't this just a hydroelectric dam then?

  • Jon
    Jon 6 months ago

    hell yeah ive been there

  • mellowfish316
    mellowfish316 6 months ago

    So would so say the rain is a trickle charger?