Britain's Largest Battery Is Actually A Lake

  • Published on: 05 November 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)

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  • Runtime : 4:56
  • tom scott tomscott amazing places dinorwig llanberis electric mountain engie


  • Seal Of Apoorval
    Seal Of Apoorval   3 days ago

    Wait what drives the "pump" later in the night? Wouldn't it take just the same amount of energy to push the water back up as it produced ?

  • ZORAN S.
    ZORAN S.   4 days ago

    Why not just build magnetic motor generators??

  • Crypt1cmyst1c
    Crypt1cmyst1c   4 days ago

    I've thought about this sort of system before used in somewhere coastal where solar pumps water to a reservoir and you generate hydro to power the grid. solar creates a lot of excess energy during the day but nothing at night, so how do you store all that energy for night use? here you go.

  • Rob VanCamp
    Rob VanCamp   5 days ago

    I gotta wonder how much energy it takes to pump the water back up...

  • Madcatlover
    Madcatlover   5 days ago

    Just like the snowy hydro scheme in Australia

  • Jason Scherer
    Jason Scherer   6 days ago

    4:16On the sign:"Dim cerddwyr tu hwnt ir fan yma"Welsh people - who hurt you? :'-)

  • Pheonix
    Pheonix   6 days ago

    Is there no way you could use the pressure realise as a method of getting water up to the top without using extra energy

  • samxyx
    samxyx   1 weeks ago

    I feel like I'm missing something.If energy can't be created or destroyed, how does the plant create an energy surplus if it constantly has to restore the water to its original height? Does it not take the same amount of energy to move the water back up as is created when it comes down?

  • RRP
    RRP   1 weeks ago

    Did they not make this for kettle surges through tv programs and sports. Brits like their tea. Edit, watched the video...

  • Blazed-Banana
    Blazed-Banana   1 weeks ago

    I remember going here as a kid! We were meant to go up mount snowdon that day but the weather didn't allow it and thank god for that! This place was way more awesome than some mountain!

  • xsara123
    xsara123   1 weeks ago

    Is that...Bud from Married With Children? Congrats on finding something to do after the show ended :D

  • DiabloMinero
    DiabloMinero   1 weeks ago

    Unlike lithium ion batteries, this actually has a big, heavy turbine to help it maintain frequency.

  • Comfort Zone
    Comfort Zone   1 weeks ago

    How can the turbine act as a pump in this case? Yes technically they are same, but the turbine impeller has to sit above the discharge and the pump impeller would have to sit under the water to pump, unless they move impellers on the shaft to convert between turbine and pump.

  • Debraval Reyes
    Debraval Reyes   2 weeks ago

    Why do shills use words in science you cant prove and create ?

  • furrywaffle
    furrywaffle   2 weeks ago

    The biggest battery earth can use is the sun.

  • Peter Parker
    Peter Parker   2 weeks ago

    I thought the lake is full of lithium ion

  • Yalike Jazz
    Yalike Jazz   2 weeks ago

    Electric Mountain. Sounds like it is in some Pokemon game.

  • MrAnory
    MrAnory   2 weeks ago

    Very interesting, what would be the total power that this power station can generate from when the lake is full to the minimum level that is allowed and what would be the energy need to fill up the lake again from the minimal level to the normal level. would the power generated and the power needed be the same ? My guess would be that the power required would be greater to fill it up again. Nevertheless its a nice piece of engineering

  • lloyd sampson
    lloyd sampson   2 weeks ago

    Southern Cal Edison should do this with San Onofre songs 2 and 3.The grid is there, the generators are there to create electricity.All that's needed are pumps, piping to the mountain range across Interstate 5, creation of a storage lake on top of the mountain, one or two turbines, and the will to get it done.Each generator creates 1100 megawatts of power, so that's 2200 megawatts of available generating capacity standing still being wasted.

  • Smatty 171
    Smatty 171   2 weeks ago

    I’ve been there it’s really interesting

  • Wild Blunt Hickok
    Wild Blunt Hickok   2 weeks ago

    Oh thank god. I thought you were about to describe a lake horribly polluted with heavy metals or something like that.

  • Yorkshire Gold
    Yorkshire Gold   2 weeks ago

    Not as good as a dam though, a dam can keep a sustained power flow

  • Barnabás Nagy
    Barnabás Nagy   2 weeks ago

    How much power does it take to pump up the water back up again? Is it not too loss-making? I'd imagine it's not less than what the turbines generate - that would be free energy.

  • donaastor
    donaastor   2 weeks ago

    Can anybody explain me (please) how is it effective to pull that water back? Isn't that a perpetuum mobile?

  • sad reee
    sad reee   2 weeks ago

    If I was smart this type of work and creative engineering would be my dream job

  • John Smith
    John Smith   3 weeks ago

    “Water isn’t compressible”That isn’t completely accurate.

  • James Collins
    James Collins   3 weeks ago

    There was one of these built on the eastern shore of Lake Michigan in the 1970s. It had an 85% efficiency rating. There might have been some built even before that.

  • tyson koster
    tyson koster   3 weeks ago

    so pumping the energy back up takes less energy than iy generates going down than isnt this infinity energy ?

  • Robert Sturgess
    Robert Sturgess   3 weeks ago

    So at night you burn coal to produce power to pump the water back up , not really helping are you just making money.

  • SANG
    SANG   3 weeks ago

    So it just wastes energy? Nice