back to article Water pipes hold flood of untapped electricity potential

There is a wealth of untapped hydroelectric potential in the United States – around 1.41GW of energy flowing through pipes, irrigation channels, and aqueducts. Scientists at Oak Ridge National Laboratory (ORNL) reached this conclusion after what they described as a first-of-its-kind study examining the potential power …

  1. Mike 137 Silver badge

    The elephant in the water pipe?

    Nothing is free in physics. The energy "generated" (i.e. converted into electric current) is extracted from the kinetic energy of the water flow. Consequently that flow will be less energetic on the downstream side. I see no mention of the effects this might have on water services, but particularly in the case of large field irrigation (e.g. in agriculture) this could be of significance.

    1. Version 1.0 Silver badge

      Re: The elephant in the water pipe?

      We see a lot of high pressure water deliveries in the southern United States ... for example Florida after Hurricane Ian went through.

      So putting generators in the rivers and organizing things to generate electricity and avoid flooding might work in future. Locally the Mississippi is only about 5 to 6 feet at the moment, but we see flooding potentials when it goes above 30 feet every year - it would be a lot of work to create a non-flooding power generation environment but it could be very helpful.

      1. Jim Mitchell

        Re: The elephant in the water pipe?

        Power generation that only works during and after a flood doesn't seem like a good investment. Your potential power consumers have either fled or are underwater themselves.

      2. DS999 Silver badge

        Re: The elephant in the water pipe?

        So putting generators in the rivers and organizing things to generate electricity and avoid flooding

        Avoid flooding how? The only way to do that is to build a reservoir to hold the water upstream, which means trading unplanned flooding downstream for planned flooding upstream. Given the size and flow rate of the Mississippi when it is flooding, that reservoir would have to be massive. Who is going to pay to buy out all those landowners and build this massive artificial lake (whether permanent or used only during floods) to your north? Maybe they would rather have the reservoir further north instead, but the further it is from where you live the less effective it will be in actually preventing flooding.

        Plus that would give people a sense of complacency and think they can build in places where they know they can't build today because it floods all the time. I have a reservoir upstream of me (on a river much smaller than the Mississippi, but which flows into it) and everyone assumed we would never have a flood. We've had two in the past 30 years, including one where the water level in the reservior was 5' above its max capacity - i.e. 5' of water going over the spillway, so the river flow was 12400 cubic feet/sec instead of the "maximum" the dam was capable of letting out normally of around 2500. Result: flooding all over town, including a lot of newly built areas that "will never flood".

        1. Version 1.0 Silver badge
          Gimp

          Re: The elephant in the water pipe?

          A few comments and probably down-votes from non-locals - so here's a little more information to describe the locality.

          The Mississippi river is locally only about 2300 ft wide and 50 ft shallow. It flows through a few cities in Louisiana but has embankments (locally called levees) that prevent flooding with a few discharge openings in the countryside that can redirect flood levels through wild areas with virtually no floodable housing - a house might be on pillars 10-15 feet high or the local town surrounded by levees. Redirecting water to keep the river level reasonable is an annual thing done most years with the advantage of allowing sediment out to strengthen the coastline. Adding the ability to generate power would not be a huge change.

          Allowing water to generate power, while making the local crayfish happy (icon), is a genuine possibility that could be done without any serious flooding issues and might help us as the sea level rises, by depositing sediment on the coastline.

          1. DS999 Silver badge

            Re: The elephant in the water pipe?

            I didn't realize they had deliberate breaks in the levees down south. I guess at some point you have to concede you can't fight a river that large and have to let it do what rivers want to do.

            1. Version 1.0 Silver badge

              Re: The elephant in the water pipe?

              LOL, locally we just see it as a decent river - back in 2016 we got about 7 trillion gallons of rain on us one week and most of the local rivers caused flooding but the Mississippi was not a problem at all with no levee issues.

            2. Michael Wojcik Silver badge

              Re: The elephant in the water pipe?

              Right until ORCS fails and the Mississippi changes course, with a massive economic cost. And not just to the US, since most US grain exports will suddenly become unavailable.

              The attempts by the US to control the Mississippi are in all likelihood doomed, and sooner or later it will all end in tears.

              1. DS999 Silver badge

                Re: The elephant in the water pipe?

                I just saw a couple days ago that the current issue down there is due to the extreme drought in much of the US west of the Mississippi recently the water level is so low barges are becoming stranded. If that continues for a long period then grain exports from the US will be greatly reduced which won't be good for the world.

                So monster floods changing the course of the Mississippi aren't the only potential issues.

          2. Anonymous Coward
            Anonymous Coward

            Re: The elephant in the water pipe?

            Isn't it a problem that flooding would only be generating for a few days a year, whereas demand, averaged over 24 hours, is constant. So the energy has to be stored to be useful. The obvious storage would be building a dam, but that would be extending the flooding time frame, and also wouldn't be reliable in years of no rainfall. I don't quite get it.

        2. John Brown (no body) Silver badge

          Re: The elephant in the water pipe?

          "Avoid flooding how? The only way to do that is to build a reservoir to hold the water upstream, which means trading unplanned flooding downstream for planned flooding upstream."

          Some points, nor especially related to the Mississippi or other large rivers, but slowing down the overall flow helps with flood control. Whether that be by adding back meanders that used to be there until people straightened them out for whatever reason, allowing "natural" damming, not dredging ,or creating flood plains/reservoirs upstream where people etc won't be flooded out, are all ways of helping. reduce the levels or amounts of flooding downstream where people and businesses could be affected rather more badly. Planned flooding is always better than unplanned flooding since you know exactly where it will happen and be prepared for it. That probably won't work near the coast where the flooding is sometime caused by storm surges, that's a whole different problem.

    2. b0llchit Silver badge
      Joke

      Re: The elephant in the water pipe?

      But it was calculated on a green computer with green desktop background. The report was printed on (olive) green paper and a very dark green ink was used in the printing process. The research was performed with green hands and all have been washed in natural green. The only non-green affects were the mauve glasses of the data processors and writing staff.

      Therefore, no negative side-effects can be seen as all has been properly green and mauve filtered. The green paper also outlined advice for the next generation on how the colours green and mauve can be reused effectively for any additional reports.

      1. Commswonk

        Re: The elephant in the water pipe?

        ...the mauve glasses...

        I take it you mean "rose - tinted spectacles".

        1. b0llchit Silver badge
          Pint

          Re: The elephant in the water pipe?

          But using "rose - tinted spectacles" would be too obvious, wouldn't it?

        2. Code For Broke

          Re: The elephant in the water pipe?

          Well done on you. You got the joke. Round of applause, everyone!

    3. The Man Who Fell To Earth Silver badge
      Boffin

      Re: The elephant in the water pipe?

      Microgeneration of hydroelectric is, like all hydroelectric, gravity fed. I looked into Powerspout's ~1kW micro-hydroelectic for our cabin in Vermont a few years back to supplement our 7kW solar installation. A 1kW or 2kW generator does not sound like much, until you realize it will run 24/7 while solar usually does not hit it's max rating on most days even for a few minutes.

      https://www.powerspout.com/

      1. Richard 12 Silver badge

        Re: The elephant in the water pipe?

        Where does the water go afterwards?

        There's only generation if it's flowing.

        It almost certainly takes more energy to make potable water than you could recover in a turbine, and water for irrigation is valuable too.

        So the generation only exists while the water is being used for something else.

        1. This post has been deleted by its author

        2. John Brown (no body) Silver badge

          Re: The elephant in the water pipe?

          If you are talking a rural cabin in the woods such the one in Vermont the OP mentioned, I'd assume he has a local stream (or creek now El Reg is American) with enough of a drop in height to give a constant flow to a generator. Depending on location and local planning/conservation regulations, he might be able to divert the stream and create "mill race" and divert some or all of the water via a pipe in the turbine. As he says, if he can get 1-2KW from it 24/7, that's a decently useful amount.

          There are also Archimedes screw type generators for slow moving, low drop rivers where a portion of the water is diverted to drive the screw using a much more significant mass of water depending on the length of the screw so can still generate a decent amount from a slower rotation passed through a gearbox. These are actual devices out in the field now and have been for some years.

          Here's an example at Cragside House a few miles up the road from me and covered by El Regs own Geeks Guide back in 2019. Back in the day, it was "the house of the future" with many "modern" gadgets mainly powered by either hydraulics or electricity generated from hydropower, so nice to see it getting up to date with modern hydropower.

          1. Michael Wojcik Silver badge

            Re: The elephant in the water pipe?

            Exactly. There's no point in putting it on a well system, for example. This is a potentially useful technique if you already have gravity-fed water available locally, and you're not making use of the full kinetic energy available (as you might be if, say, you have rain catchment into an elevated tank, and you use the pressure to irrigate a garden plot).

    4. Steve Davies 3 Silver badge

      Re: The elephant in the water pipe?

      Nothing is free in Physics... good point

      Then, old Newtonian physics comes along and makes it even more complicated.

      There are a load of ads on YouTube promoting these miracle heaters. They are supposed to heat a large room in seconds for a few pence.

      This wonder device has been invented at MIT, a school in Scotland and by NASA to name a few.

      One of the ads even mentions the words 'Perpetual Motion'.

      Scams. There is no such thing as a free lunch.

      What is theoretically possible is a long way from a practical implementation. How long have we been saying that free electricity from Nuclear Fusion is 20 years away?

      Consider me sceptical.

      1. Solviva

        Re: The elephant in the water pipe?

        Sadly I don't get to enjoy youtube ads but are these the miniature ca 500W resistive heaters that strangely produce 500W of heat, but use only 500W and so heat your room much cheaper than a say 2kW heater [which provides 4x the heat]. Magic!

        1. Anonymous Coward
          Anonymous Coward

          Re: The elephant in the water pipe?

          "the miniature ca 500W resistive heaters that strangely produce 500W of heat, but use only 500W and so heat your room much cheaper than a say 2kW heater [which provides 4x the heat]. Magic!"

          Might it be this one?

          BigClivedotcom - "Miracle" heater teardown - with schematics

          https://www.youtube.com/watch?v=sPnLnk35XsY

          Technology Connections has one on similar lines.

          1. Peter Gathercole Silver badge

            Re: The elephant in the water pipe?

            But Clive comes to the conclusion that as long as they are made well, they can be useful in specific circumstances, as one of the ones he took apart was one that he uses to help keep his legs warm his 'studio' (if you watch some of his videos, you find that his studio is not very warm).

            No, not a miracle heating solution, but useful in some circumstances.

      2. Anonymous Coward
        Anonymous Coward

        Re: The elephant in the water pipe?

        Well, last Fall I bought two fleeced robes ($40 each) for me and my wife, and two avg 50W foot warming pads, one avg 100W kotatsu heater to attach under my wifes chair (I stand at my desk so don't need one), and an electric blanket for sleeping. And turned off the gas heating at the master switch so it was never on during Winter. The room air is better and its kind of a cozy fresh feeling, no problem when the inside ambient temperature only goes down to 5C/40F anyway (Northern CA, East Bay Area). We can open the windows in the afternoon without worrying about letting the heat escape.

        I measured my wife's chair's seat temperature with the avg 100W kotatsu heater on and her long robe hanging over the edges of the chair to trap the heat - 38C - like a mini dry sauna. Take away the robe and the effect of the 100W kotatsu heater is imperceptible, the chair is barely warm and the room temperature doesn't even rise 1C.

        So I guess miracles can happen.

        1. Solviva

          Re: The elephant in the water pipe?

          Humans make a fair bit of heat, insulate them and indeed they feel warm. Add a little extra heat input and get your own personal sauna as you say :)

          1. vogon00

            Re: The elephant in the water pipe?

            and indeed they feel warm.

            Someone once mentioned that 'When you "turn the heating up"', you are actually reducing your personal apparent rate of cooling to something more comfortable, meaning the local environment conditions allow your body to self-regulate it's temperature using it's normal functions.

            Once we get outside the part of the curve where thermal management is simple (e.g. pull blood away from our surface area to avoid excessible heat loss), that's where we start needing to do something a bit more complex like generating additional heat energy by shivering, or increase the rate of heat loss using the evaporation of sweat.

            I love using the phrase 'I'm just going to turn the cooling down', as it feels more correct to me!

      3. MachDiamond Silver badge

        Re: The elephant in the water pipe?

        "Nothing is free in Physics... good point"

        Nothing is free in engineering either. Micro generation is a niche way of making electricity. It's expensive which is why big hydro is what we normally see. I don't see how extracting energy from water mains is a good idea. It's like attaching a wind turbine to the car or using the drive shaft to turn an extra alternator. If pumps had to be used to pressurize the water in the pipes to begin with, taking it out with a turbine is a net loss.

        I had occasion to look at the "Master Fee Schedule" for a couple of cities in the US and they want payment for everything. Do you want to put up a fence, there's a fee. Want to take a fence down, there's a fee, Need to replace a fence, there's a fee even if nothing about the replacement is of new design/dimensions. Even though the city is funded with taxes, they also charge $131/hr if an employee does anything for a citizen and more if it's on the schedule. They bring in so much money in my town from these fees that they can pay a miserable old, large hag to drive around in a Fordasaurs looking for people that are doing something without paying a fee first. I would bet that in many places, the fees to legally install a micro-turbine would be more costly than the power might be worth for the first couple of years.

        1. Michael Wojcik Silver badge

          Re: The elephant in the water pipe?

          If pumps had to be used to pressurize the water in the pipes to begin with

          This appears to be the part of the proposal you're missing. It's for water supplies that are gravity powered, thanks to water sources at higher elevation than the consumers.

      4. Michael Wojcik Silver badge

        Re: The elephant in the water pipe?

        They are supposed to heat a large room in seconds for a few pence.

        To be fair, I have a technique which can heat a large room in seconds for a few pence, for certain values of "large", "seconds", and "few". The pence are spent on a flammable liquid and a match. It's a bit rough on the furnishings and occupants.

    5. DrSunshine0104

      Re: The elephant in the water pipe?

      My thought originally but I would imagine the engineers would account for any pressure loss in the system and size pipes, valves, etc accordingly. Maintaining pressure in the water system is not only important for service expectations but water safety too. If the feeder to the impeller is big enough compared to the mains to the rest of the community the losses wouldn't really manifest. Nothing is free but gravity is as close as you can get, it would take time/space, and assuming the engineers balance the flow through the impeller, the water in the pipe would would pressurize because the head of the water column didn't change, gravity is still there 'pressing' down on the water.

      1. david 12 Silver badge

        Re: The elephant in the water pipe?

        I'm thinking that surely the authors must be writing about water channels, not distribution pipes.

        Distribution pipes in the USA are sized to deliver the minimum required pressure to each home, and any change to upstream pressure will make the whole system non-compliant. That, and it's illegal (?) for end users to use water for power generation because it increases water loss.

        1. John Brown (no body) Silver badge

          Re: The elephant in the water pipe?

          "That, and it's illegal (?) for end users to use water for power generation because it increases water loss."

          I think I recall seeing a shower-head that used the water flow to power either LEDs or a radio. Some sort of silly gimmick anyway but I suppose it did work and generated power from consumer water flow :-)

          1. trindflo Bronze badge

            generating electricity in a shower-head

            What could possibly go wrong?

            1. Crypto Monad Silver badge

              Re: generating electricity in a shower-head

              At 5 volts, not very much.

              If you want something properly scary, try using an electric shower in Central or South America - a.k.a. "suicide shower". They consist of a shower head with in-built heating element; the live/neutral wires connect directly to it, usually via a terminal block with some tape wrapped around.

              They are mainly made in Brazil, and examples are easy to find online.

  2. SonofRojBlake

    Back to the Future

    "1.41GW figure is probably way lower than the actual potential."

    If it's acknowledged as being a lowball estimate, why didn't they do the decent thing and "estimate" 1.21GW for full Doc Brown credibility?

    Also - it's unclear who will suffer from having the energy removed from the water flow, but it's highly likely to be consumers. Shitty low-pressure shower anyone? Ten minutes to fill your kettle for a brew? (Oh, I forgot - it's the USA, no decent cups of tea there hence no kettles. OK, coffee machine then.) Someone has to suffer - ye cannae break the laws of physics and specifically Bernoulli's equation.

    1. Paul Kinsler

      Re: Back to the Future

      I would suppose there are some downhill pipes/conduits/whatever where the water actively needs to be slowed down, so managing that process with hydro generation as opposed to passive baffles or whatever would make sense.

      1. John Brown (no body) Silver badge

        Re: Back to the Future

        I suspect that's the sort of thing the authors are on about. After all, even a "low ball" estimate of 1.41GW across the entire US is a relatively small amount. That indicates either very few places it could be done or very many places where the output is too low to make any economic sense. It might be they are suggesting generation from gravity fed pipes to generate power for use within the water supply system, eg running control valves, powering telemetry or possibly even powering pumps further down the system, especially in out of the way places where they are using generators or batteries.

    2. Anonymous Coward
      Anonymous Coward

      Re: Back to the Future

      1.21 gigawatts! 1.21 gigawatts. Great Scott!

    3. HereIAmJH

      Re: Back to the Future

      Also - it's unclear who will suffer from having the energy removed from the water flow, but it's highly likely to be consumers. Shitty low-pressure shower anyone?

      My guess is that in most municipal water systems, adding micro hydro in the delivery pipes would end up requiring more pumps or taller towers to maintain acceptable pressures. If the pressure drops too much you also risk back flows that will contaminate the water.

      There are probably situations where reservoirs and water sources are at higher elevations than necessary, but I doubt there are very many.

      1. trindflo Bronze badge

        Re: Back to the Future

        Not to mention that all the municipal pipes in the US leak; some badly.

    4. Andy A
      Facepalm

      Re: Back to the Future

      Nobody else seems to have noticed the OTHER figure mentioned in the article.

      The existing installed 530MW is more than a third of the "potential" figure of 1.41GW.

      Not such a big step once you mention that, is it?

  3. Sandstone
    Headmaster

    Grammar, please...

    "Further, as water infrastructure ages and need replaced, that upgrade can include some power generation potential."

    This should be either "needs to be replaced" or "needs replacement."

    1. SimonL

      Re: Grammar, please...

      "Where's your grammar?"

      "She's upstairs havin a nap."

    2. John Brown (no body) Silver badge

      Re: Grammar, please...

      It's the new "North American Style Guide" used by El Reg these days. AFAIK, that means "anything goes" now since US grammar seems to be whatever the person speaking or writing wants it to be ;-)

  4. Anonymous Coward
    Anonymous Coward

    Slower water=more nasties

    That need 2GW to treat.

    There really is no such thing as a free lunch.

    Malaria is my first thought.

  5. martinusher Silver badge

    Magic Energy?

    The head of water is purely artificial in most water distribution systems. Locally we design for 'fire flows' -- forget opening a tap to fill a kettle, we need enough pressure and flow to keep the fire department happy and we do this by positioning tanks on hilltops. The water in those tanks has to be pumped up to them; it actually came from about 500 miles away and went across a couple of mountain ranges to get to us but that's modern engineering for you.

    I'm sure there's places where water flow is entirely gravity driven (Manchester's system was designed like this) but its probably one of a minority of systems.

    (What on Earth do they teach people under the guise of 'science' at school these days?)

    1. Mike 137 Silver badge
      Joke

      Re: Magic Energy?

      "The water in those tanks has to be pumped up to them"

      So we could use electric pumps to raise the water and then put generators in the downward flow. With any luck the magic would permit perfect matching of the energy conversions so the generators would power the pumps.

      1. Commswonk

        Re: Magic Energy?

        So we could use electric pumps to raise the water and then put generators in the downward flow. With any luck the magic would permit perfect matching of the energy conversions so the generators would power the pumps.

        I wish you hadn't written the above; it won't be long before a politician opens his or her mouth in the belief that you were serious, followed by "why isn't this happening now?" Politicians and anything technical do not make a good mix.

        1. Steve Davies 3 Silver badge
          Boffin

          Re: Politicians mouths

          Let them spout it. Then calmly remind them about perpetual motion machines, snake oil salesmen and lies.

          When a politician opens their mouths, it is to lie.

        2. Giintak

          Re: Magic Energy?

          To be fair, that is basic pumped storage for renewables. Use excess solar to fill large tanks, run it through turbines overnight. Easiest way to store large amounts of energy without toxic stripmining to make batteries. It's an idea already in use and likely to be expanded greatly.

      2. BenDwire Silver badge

        Re: Magic Energy?

        Given that Dinorwig Power Station (Electric Mountain) manages about 75% efficiency then that magic had better be strong stuff.

        1. Anonymous Coward
          Anonymous Coward

          Re: Magic Energy?

          Dinorwig Power Station is still around. Marvellous stuff, here's a taster from that Wiki article:

          "When the plant was conceived the CEGB used low efficiency old coal and oil fired capacity to meet peaks in demand. More efficient 500 MW thermal sets were introduced in the 1960s, initially for baseload operation only. Dinorwig could store cheap energy produced at night by low marginal cost plant and then generate during times of peak demand, so displacing low efficiency plant during peak demand periods.

          ...

          Dinorwig is operated not only to help meet peak loads but also as a short term operating reserve (STOR), providing a fast response to short-term rapid changes in power demand or sudden loss of [power input to the National Grid]"

          More in the article. Reference 17 may be oarticularly revelant.

          Inevitably, "market forces" decided in the last few years that grid-scale storage (of electricity or gas) on a timescale between weeks and seasons is no longer relevant (see e.g. Centrica/Rough gas storage abandonment ten years or so ago, and more recently, gas (and hence electricity) supply constraints in europe and related threats of nuclear war - who would have thought the all-knowing markets didn't see that one coming).

          So Dinorwig's combination of near 10 GWh storage capacity and near 2GW output is now most profitable if it is used for fast (a few seconds) short term response to grid-scale demand changes, to stop the grid going into chaos if the change in demand and resulting change in frequency wasn't properly managed.

          A more "modern" response to frequency stability might be to use regional (rather than national) AC->storage->AC setups on a variety of grid-connected sites using similar AC->DC->AC technology to what's in the cross-channel links etc. GW scale input and output, with the addition of enough stored GWh to "peak lop" in the region when needed.

          Until relatively recently, the solid state power electronics and frequency control were either not up to the job or not affordable.

          In recent years, high power solid state electronics are more than capable, and affordable (if compared appropriately with the cost of loss of power). Same for the control systems.

          ABB (and presumably others) have been marketing this as "virtual inertia".

          1. Solviva

            Re: Magic Energy?

            "virtual inertia" love that! Describes well solar & wind.

            The Grid relies on inertia from the large generators to keep the frequency stable - replace these with unstable renewables and expect consequences. Unfortunately most politicians don't understand that and seem to assume you can replace an X GW nuclear generator with X+(some extra capacity) renewables and nobody will notice (or just shut down the dirty nuke plants, don't plan for any replacement (yeah energy comes if you dream enough) and bury your head in the sand blaming Putin). Sweden + Germany spring to mind....

            1. Anonymous Coward
              Anonymous Coward

              Re: Virtual Inertia (again)

              "The Grid relies on inertia from the large generators to keep the frequency stable"

              Oversimplification.

              "replace these with unstable renewables and expect consequences."

              Oversimplification.

              Please seek well-nformed enlightenment. This may be a starting point:

              UK Grid did used to have a designed-in and tried tested and proven reliance on real mechanical inertia from GW-scale power station turbines etc. Its limitations were well understood and were why Dinorwig's superfast response was actually just as important (and eventually more important) than the ability to store multiple GWhours worth of electricity over an indefinite period (and that's wthout even considering BlackStart capabilities).

              A necessary consequence of the Grid's designed-in reliance on mechanical (and also thermal) inertia was that real system inertia could not be used to provide fast response (low seconds, preferably less) to GW-scale changes in demand. Back then the slow response could also be viewed as "a feature not a bug", but realistically it needed so-called "spinning reserve" (boilers up to temperature, turbines up to speed) to be able to respond reasonably rapidly to grid-scale changes in demand. That was an unnecessary waste of fuel.

              Big thermal stuff (with boilers, steam turbines etc) had a response time of hours (maybe a bit less) to warm up from cold. Other options were needed, back in the 60s/70s pumped storage was a viable option - a big investment with a valuable (but not necessarily profitable from a beancounter viewpoint) return.

              Some years later, the combination of utility privatisation and the insanely short-sighted "dash for gas" meant that it became profitable to abuse valuable natural gas in gas turbine engines driving AC gererators on the scale of tens of MW per set These were often repackaged repurposed derated airline jet engines (sometimes combined with heat recovery from the exhaust) which had a response time in the low minutes and an output of (say) 50MW electric from e.g. Rolls Royce Trent 60. These CCGT power stations became rapidly became widespread "quick to profit" abusers of a valuable "when its gone its gone" resource - North Sea gas.

              Then in the early days of distributed decentralized generation the unforeseen outages did start to happen. Some got reported and documented and investigated because of their unexpectedly widespread effects. E.g. the Sizewell and Longannet failure(s) in 2008.

              Much more recently there were the wide area outages of August 2019 and theirunexpected consequences across the UK, e.g. of systems which did not properly handle (had not been properly specified to handle?) "must never happen" levels of supply frequency disruption.

              e.g.https://www.ft.com/content/49d94586-bb47-11e9-b350-db00d509634e (Aug 10 2019, paywall)

              (to be continued)

              1. Solviva

                Re: Virtual Inertia (again)

                Oversimplication it may be, but it's not wrong.

                Indeed for the traditional Corrie-break-kettle-boil moments (which were so predictable they can be ignored) you need a PDQ ramp up of supply. For solar and wind - do you pray to Njord for some wind when this happens? Pray to Sol if it's daytime?

                Wind & Solar most definitely have their place in modern energy production, but without any ballast to support their and the consumers' fluctuations then you need a rather responsive on-line generator that can ramp up (or down) - gas, nuclear, hydro (coal & oil if you're that way inclined).

            2. Anonymous Coward
              Anonymous Coward

              Re: Magic Energy?

              "Unfortunately most politicians don't understand that and seem to assume you can replace an X GW nuclear generator with X+(some extra capacity)"

              Depends on where you are talking about.

              In the USA, for example, you probably could really rely much more on weather-dependent generation, but it would need a proper high capacity power transmission network around the USA, and a massive investment in multi-MW and GW of wind generation, and maybe even a few hours worth of storage in some places. This works in the USA because it's a big country with lots of room, so big that the whole of North America will never be covered by a single weather system and so it will always be windy *somewhere* not too far away. You just need to get the energy from where the wind is to where the demand is (and/or from the time the wind is to the time the demand is... take your pick).

              A good starting point might be grid-scale energy efficiency. in large energy users. Talk of turning off phone chargers is pointless. On the other hand, Bloomberg appears to be hinting at Intel's imminent extinction, which might finally lead to the overdue death of huge numbers of ridiculously inefficient servers and such Wintel boxes.

              Not read it on El Reg yet? Start here and draw your own conclusions:

              https://www.bloomberg.com/news/articles/2022-10-11/intel-is-planning-thousands-of-job-cuts-in-face-of-pc-slowdown

              Bloomberg? Intel? As in SuperMicro? Hmmm.

              https://www.bloomberg.com/features/2021-supermicro/

              Respect as always to the late Professor David Mackay

              https://www.withouthotair.com/

              https://en.wikipedia.org/wiki/David_J._C._MacKay

        2. MachDiamond Silver badge

          Re: Magic Energy?

          "Given that Dinorwig Power Station (Electric Mountain) manages about 75% efficiency then that magic had better be strong stuff."

          Depending on how the efficiency is being measured, it can be as low as 25%. What pumped storage can be good at is using up something like wind power if it's a choice between pumping water uphill or turning the turbine off. It could wind up being more efficient to transmit leccy prices down the lines and when there is a surplus, EV's that are plugged in can take up the load once the price hits a certain point. If that comes to pass, pumped storage might see a big drop in usability.

          1. Anonymous Coward
            Anonymous Coward

            Re: Magic Energy?

            "It could wind up being more efficient to transmit leccy prices down the lines and when there is a surplus, EV's that are plugged in can take up the load once the price hits a certain point. If that comes to pass, pumped storage might see a big drop in usability."

            In principle yes, which is why V2G ("vehicle to grid") has been discussed and prototyped for years (Renault, Paris, 2015 comes to mind). And in some ways it might be even easier than you think. But it may come with non-obvious snags.

            Review: Some core components of a worthwhile battery electric vehicle setup are:

            1: AC->DC to charge battery

            2: Worthwhile Battery

            3: DC->AC to power the motors (or feed the local mains demand, just as you need with e.g. solar PV grid-tied inverter)

            4: controls to make it all work (again like a grid-tied inverter)

            5: connectors and cables to tie it all together

            6: competent installers, repairers, etc. - could be tricky but no trickier than e.g. solar PV or Tesla Powerwall.

            Sound familiar? Change the packaging slightly and it's either e.g. a Tesla Powerwall or e.g. a Nissan Leaf. or it's solar PV. Not rocket science.

            You don't really even need to transmit prices down the line. Real time prices appear to be based on "demand vs supply" situation at national grid level. The live grid frequency acts as an indicator of supply vs demand:

            * if grid frequency > nominal then national supply exceeds national demand - opportunity to charge your Powerwall/BEV from discount mains

            * if grid frequency < nominal then national demand exceeds national supply, so use your BEV/Powerwall to do V2G (and get paid for it?).

            Boutique ISP AAISP's top ubergeek and bloggist, Reverend Adrian Ke

            nnard, is trying this out in his own home right now, and writing about it at www.me.uk. If EL Reg hadn't become so 60Hz/120V-centric, it might even be worth commissioning an article.

            Extract from Revd Kennard: "Because the battery can charge up on the excess solar and then be used to power the house, whist the battery is not full, and whilst we are not making excess solar more than 5kW, the battery takes the power.

            In the morning, if there is enough sun to fill the battery as above, all of that extra sunshine can be used any time during the day and it will just delay the point the battery is full. So costs me the export (5p) that I am reducing. But once passed that, at the point the battery does not get full, any usage will simple mean the battery runs out faster and so will mean power from the grid, so cost me normal rate (currently 24p)."

            Worth a look.

            But note that price (and frequency) are set on a national basis, whereas connectivity to the mains is very definitely location dependent. Dinorwig's high power bidirectional connection direct to the National Grid means it can be fed from, and feed to, anywhere in the UK (and, in principle, anywhere in the UK grid can supply e.g. France, Norway, etc). Up to say 2GW worth, in Dinorwig's case.

            In contrast, any power from a domestic setup can only feed that domestic installation, it cannot physically feed back into the local distribution network. IE they can reduce demand but not increase available supply. A hundred homes each offering a 20kW reduction in demand (it won't usually be that big) isn't quite the same as a genuine 2MW input into the grid. The nature of the wiring, and the way to control it, start to become important.

            On the other hand, if you can find (say) a thousand premises each with a (say) 10MW connection, maybe two resilient 1connections, with associated engineering skills, maybe up to 10GW of dynamically controllable demand or supply could get interesting. Think about, for example, hospitals. But that one only works if joined up thinking is allowed and encouraged. Or, maybe, large shopping centres, office buildings, etc.

            Still worth looking at though, unlike electric powered commercial aircraft with more than 29 passengers (or is it 19). Electric aircraft will never be able to use the "regenerative breaking"(!) features needed to make battery electric vehicles practical. Never. That's physics, and ye canna change the laws of physics, and you can't even bend them for long.

            The 29 (or is it 19) passengers on an electric aircraft is a regulatory/legal thing related to type approval etc, and as Disruptor-in-Chief Truss is currently showing, regulatory/commercial/legal things can be changed quite quickly and quite frequently but the disruption doesn't necessarily have any useful effect. Still doesn't help electric aircraft though 'cos physics trumps truss. Oooer.

            1. MachDiamond Silver badge

              Re: Magic Energy?

              "You don't really even need to transmit prices down the line. Real time prices appear to be based on "demand vs supply" situation at national grid level. The live grid frequency acts as an indicator of supply vs demand:"

              The grid operator is always working to keep the balance so that could mean supply is taken off. If instead load is added through EV's charging, that's a better way to keep the balance. Right now, V2G is very limited and the CCS spec needs to be updated for that to be more universal so let's just stay with EV's taking power from the grid first and get that working. Drop the price and it's a good deal for EV owners and wind turbine operators as well so there needs to be some mechanism to tell EV's about the lower price. Wind power is often the first to be taken off in the case of over supply as it's the most difficult to deal with. Aside from clouds passing over, solar is pretty steady and predictable.

    2. Stork Silver badge

      Re: Magic Energy?

      I guess the pumping to the hilltop is the same no matter what is done later. That would mean that as long as it doesn’t bother the fire service, there could be potential for _recovering_ some energy.

      1. Commswonk

        Re: Magic Energy?

        That would mean that as long as it doesn’t bother the fire service

        It shouldn't; fire appliances do not normally rely on supply pressure to fill the hoses, at least not completely. A fire appliance is equipped with serious pumps driven from the engine to pressurise the hoses so that the water can reach a suitable height and come out of the nozzle ("Monitor" IIRC) at some speed*.

        Where necessary an appliance can draw water from a static supply (e.g. a pond) although an additional "portable" pump may also be required.

        That said, there has to be a potentially significant flow rate available; LFB ran into trouble during the Grenfell Tower fire because of the extraordinary volume of water needed and they had to ask the water board (whichever one it is) to pump harder to get enough.

        * I find myself wondering how the fire services will manage when they have to use appliances powered only by batteries...

        1. katrinab Silver badge
          Meh

          Re: Magic Energy?

          Carry a diesel generator on board?

        2. PRR Bronze badge

          Re: Magic Energy?

          > fire appliances do not normally rely on supply pressure to fill the hoses,...serious pumps driven from the engine

          Yeahbut. In a big many-truck fire you can have zero or negative pressure at the hydrant. To get the water from the tower to the several trucks at the building with low pressure-loss, we need big pipes. For a major warehouse fire, MUCH bigger than local washing and flushing needs. The everyday peak flow may fit in a 4-inch pipe. To get flow at the truck at standard mains pressure when many hydrants are open may need 12" pipes. Which are a lot more expensive than the 4" pipes, but the system economics have to make sense without the fire load (fire insurance is part of this computation). Also in growing lands (US) the water mains must be funded before full economic growth. Long-term bonds help a lot but we can only mortgage the future so far.

          So a compromise. Instead of free-flowing 12" pipes, 10" or 8" pipes are installed. For anything from a flush to a house-fire this is adequate hydrant pressure. For a major fire, the pump at the tower is turned directly into the mains to force against the drag of under-sized pipes. Mains pressure near the central pump may double, leaving "some" pressure to flow into the truck-pump. (Remember you can't suck water far up.)

          A thorough reference is Water Supply and Sewage, Ernest W. Steel, 1953 (also 1938 1947 1960). There's about 40 pages on water distribution pipe sizing calculations. Almost every calculation starts from fire demand. Advantage is taken of parallel pipes, assuming the fire on 4th St can also take water from 3rd and 5th Sts via cross-mains.

          All of this suggests that, except the ball-game's half-time sewer-flush, there's no harvestable energy in city pipes.

          Except: California ran out of flat land 100 years ago, and has been building uphill since. Their water mains tend to excess (pipe-bursting) pressure unless the excess is taken-off with pressure regulators. (I remember when early regulators failed and whole neighborhoods went wet.) The same gravity works on farm-water, and California does a LOT of that. But even so, nearly every large water delivery project is broken-up with dammed lakes, and the "hydropower?" must have been considered.

          OTOH, here in Maine, we have been taking OUT small hydropower. The Federal permitting is onerous. And every year there are reports of minced fish below the turbine outlets. This is a lose/lose proposition: if flow is low to minimize fish-kill, the corpse-parts sit on the banks and smell, if flow is high to wash the kill out to sea (feed the lobsters!) the kill is much larger. There is also the reverse problem that fish can't go up-river to spawn. Several major food and sport species (trout, alewives) here have been decimated by a century of damming. (Even wing-dams deter fish.)

          I been looking at my little stream but in the last 4 years (drought) it has gone dry every summer.

          As always, California may be the Special Case. Not only do they need the energy more, they have the large-drop water systems rushing down the mountains to the sea.

          1. jake Silver badge

            Re: Magic Energy?

            "As always, California may be the Special Case. Not only do they need the energy more, they have the large-drop water systems rushing down the mountains to the sea."

            We've been using that large drop to generate electricity since the year dot. As an extreme example, the Hetch Hetchy reservoir supplies not only water, but also electricity, to the City of San Francisco (and a few other cities along the way who had the foresight to pay into the project in the late teens and early '20s). Until we build more damns, we're about tapped out. (Auburn, anyone?)

            Likewise, we've had wind turbines for a long time. All the profitable places are taken ... except along the Coast. The California Coastal Commission will not approve any, so once again California is about tapped out.

            We need to build nuclear plants. Lots of 'em. And we need to start building 'em forty or fifty years ago.

            No, California's not out of flat land. We just use most of it to feed the rest of the nation. Different, tho' related, issue.

            1. Anonymous Coward
              Anonymous Coward

              Re: Magic Energy?

              We really need some giant turbines on the Golden Gate Bridge. It would also be a deterrent to Godzilla.

    3. Steve Davies 3 Silver badge

      Re: entirely gravity driven

      Birmingham's supply from the Elan Valley is a wonderful example of a gravity system.

      These are just so elegant and simple that only the Victorians could have done them. Today, they'd be over engineered, attract a gazillion protests, cost at least £100Billion and take 30 years. And to think that we have all those wonderful machines when the Victorians had human labor and blasting powder.

      Progress? hardly.

      1. John Brown (no body) Silver badge

        Re: entirely gravity driven

        Yes. Another apt comparison would be the current HS2 project compared with the creation of the motorway network. At one point I think they were building a mile per day of motorway.

  6. SimonL

    Ay?

    But physics says No. Unless Gravity is involved, then it's a Yeah but no but, maybe.

  7. ukgnome

    Great Scott

    That's enough energy to take you back to the future

  8. gfx

    Just no

    The pressure in the pipes is supplied by pumps by maintaining a certain pressure. Using this pressure means the pump must work harder. It is not free energy.

    This is completely insane.

    1. Spoobistle
      Joke

      Re: It is not free energy.

      It is if you don't tell the pumping station what you're doing!

      1. Solviva

        Re: It is not free energy.

        If you're on an unmetered water supply you could make 'free' energy!

    2. Anonymous Coward
      Anonymous Coward

      Re: Just no

      "The pressure in the pipes is supplied by pumps by maintaining a certain pressure. Using this pressure means the pump must work harder. It is not free energy."

      Citation welcome. May be a good principle in general, but some special circumstances apply to water supply.

      "This is completely insane."

      Varies from place to place, but many agree the USA has a tendency towards insane.

      Here in good old Blighty, did you know Birmingham's water comes in pipes from the Elan Valley in Mid Wales. Birmingham is mostly lower than the Elan Valley, so mostly Mother Nature provides the transport (ie the pressure) for free. Same may apply Lake District to Manchester.

      https://www.elanvalley.org.uk/discover/reservoirs-dams/birminghams-water

      I believe Roman aqueducts used similar principles before the USA even existed.

      1. Anonymous Coward
        Anonymous Coward

        Re: Just no

        Drawing energy from that system would leave my shower even more anaemic than it already is. No thanks.

      2. MachDiamond Silver badge

        Re: Just no

        ""The pressure in the pipes is supplied by pumps by maintaining a certain pressure. Using this pressure means the pump must work harder. It is not free energy."

        Citation welcome. May be a good principle in general, but some special circumstances apply to water supply."

        Where I am is flat and our city water is from wells around town. The pressure in the mains is from the pumps and kept moderately constant by the use of variable frequency drive motors. In the middle of the US a water tower is used to maintain pressure in the water system.

        1. John Brown (no body) Silver badge

          Re: Just no

          So, obviously that means your area is one of those not considered suitable for the suggestions put forward by the authors of the paper. That doesn't mean it's not possible to do so elsewhere. Such as the existing 500+MW already in place referred to in the article. Clearly your area isn't an ideal site for building dams for hydropower. But it may well be suitable for wind turbines if it's all wide flat empty space :-)

  9. Tony W

    Read it?

    This paper is freely available, and I wonder if all those who are very rude about it here have read enough of it to be sure that their criticisms are justified. I haven't read much but it does include the sentence: "Given the data limitations, this assessment focuses only on identifying gravitational head potential without considering the additional excess head generated during pumping."

    1. Throatwarbler Mangrove Silver badge
      Holmes

      Re: Read it?

      Are you kidding? This is the Internet! Of course people are going to pop off with half-informed opinions, especially regarding how a new technology is completely infeasible, without reading the source paper!

      FIX OLD! NO NEW!

    2. I am David Jones
      Meh

      Re: Read it?

      Maybe it’s just me but actually I think an article should be pretty self-contained and if it gives rise to obvious questions then it is fair that these are raised in the comments without expectation that everyone has to first study the source material used for the article.

  10. Eclectic Man Silver badge
    Boffin

    Canal locks

    I did wonder whether installing turbines in the UK's canal lock gate sluices so that whenever the lock is filled or emptied an, admittedly small, amount of electricity would be generated (could be stored in a battery). Not all locks would be suitable but Neptune's Staircase might produce a useful amount (https://www.scottishcanals.co.uk/locations/neptunes-staircase/). And as for the deepest lock in Europe, surely that would produce something worthwhile (https://pigletinportugal.com/2016/08/04/narrow-locks-dams-and-the-douro-river-portugal/).

    1. Ian Johnston Silver badge

      Re: Canal locks

      Easy enough to do the sums. Locks in Neptune's Staircase are 55m x 12m, the total fall is 20m and it takes 90 minutes for a boat - and therefore for a lockful of water - to go through. So that's a possible average power of (55 x 12 x 20) x 1000 x 9.81 / 90 x 60 = 24 kW.

      1. jake Silver badge

        Re: Canal locks

        Assuming the lock cycled constantly, day and night, you'd get, what, about 240 times more power if you roofed it with solar panels.

        Well, maybe a trifle less in dear old Blighty.

        1. katrinab Silver badge
          Meh

          Re: Canal locks

          But there's nothing stopping you from doing both?

          1. jake Silver badge

            Re: Canal locks

            Think TROI.

            The solar roof will last upwards of thirty years, and probably over fifty.

            A small turbine (or eight, as in this case), not so much. For a mere 3kW each. No thank you. Easier to bung another 3sq meters of solar on at each turbine location.

            1. Anonymous Coward
              Anonymous Coward

              Re: Canal locks

              Have you ever been to Scotland? As wonderful as the Great Glen is, sunshine is something of a luxury!

  11. Kev99 Silver badge

    I wonder how much could be generated just from water towers?

  12. IGnatius T Foobar !
    FAIL

    This is ridiculous.

    Extracting electricity from the flow of water in pipes will reduce the flow of water to where it needs to go. That'll be great when the fire department can't pump it high enough.

    By the way, if the water was in a water tower (which most towns have), it is pumped INTO the tower USING ELECTRICITY. You're not saving anything.

    And in an urban setting, high rise buildings often need their own water towers (look at a photo of NYC rooftops) which require filling from the water mains USING ELECTRICITY.

    1. Anonymous Coward
      Anonymous Coward

      Re: This is ridiculous.

      Very few UK towns have water towers. In fact, I don't know of any.

      1. Solviva

        Re: This is ridiculous.

        They seem to be a relic from when we stored resources vs getting them on demand / just in time. Gasometers, water towers....

      2. AndrueC Silver badge
        Happy

        Re: This is ridiculous.

        If anyone who drives the M40 has ever wondered what that 'castle tower' is alongside near Bicester. It's a water tower for Bucknell (now decommissioned). I used to work in Bucknell and a lot of lunchtimes I'd walk out to Trow Pool, then along Ardley Quarry and back along a footpath through the fields. Quite a nice walk really unless Ardley was being especially pungent.

    2. John Brown (no body) Silver badge

      Re: This is ridiculous.

      "Extracting electricity from the flow of water in pipes will reduce the flow of water to where it needs to go."

      There are situations where the pressure has to be reduced. Not everyone gets water from a water tower. Having said that, would the pressure in the pipes at the bottom be lower if the generator "stealing" energy was at the top of the pipe directly under the base of the towers tank? Think about regenerative breaking on EVs. Yes, you paid for electricity to get the water up into the tower and turned that electricity into potential energy so why not see if some of that potential energy can be recovered when it turns kinetic at the top of the drop pipe?

  13. Anonymous Coward
    Anonymous Coward

    Don't freak out about it.

    We have been doing this in California for decades. The trick is it only works in specific conditions. Think of it like regenerative breaking. If you water at a higher elevation, and it ends up at a lower elevation(Almost always LA in the California examples) you can pump water over a ridge, and then recover a portion of that electricity at the far end by running it back through a turbine. If the difference in altitude is high enough there may even be a net power gain. This works in California because most of it is routed from the Sierra Nevada at high altitude, through to the Mojave Desert outside LA, at a few thousand feet. So they can pipe it over the local mountains and recover power at the low side in the LA basin reservoirs.

    While other countries may have more untapped locations, if your part of the world build a bunch of dams after the turn of the century, odd are the engineers already thought of it. Also keep in mind the scale of potential power the paper identifies reflects this. A couple of well located state of the art wind turbines will knock out as much power, and there is much more untapped potential there.

  14. jake Silver badge

    The other issue.

    Infrastructure and maintenance.

    Who is going to maintain all these micro generators? At what intervals? How much will that cost? Who is maintaining the spares? Will the spares be standardized, or will each installation be custom? Who owns the physical space the systems are installed in? Who pays the insurance on that space? Where will the staff live, and will it be in proximity to the equipment, or will they have long commutes to get to broken (or in need of maintenance) units? How about the physical tie-in to the grid? Who will own/maintain/repair that?

    Etc. etc. etc.

  15. Anonymous Coward
    Anonymous Coward

    It's 2022. Do we know where our electricity comes from?

    "you need a rather responsive on-line generator that can ramp up (or down) - gas, nuclear, hydro (coal & oil if you're that way inclined)."

    Something like that level of fast response capability is needed anyway for resilience reasons, knowing in advance what time it will happen should just make it simpler to organize. The options for delivering it have changed since last century for regulatory and technical reasons, some (e.g. embedded generation) don't seem to be well understood yet when push comes to shove (how could they be?). There's related commentary on August 2019 events via

    https://eciu.net/insights/2019/powercut-a-10-year-failure-to-act

    I've seen similar industry analysis before, but not this particular writeup. Extract at end of this post.

    "the traditional Corrie-break-kettle-boil moments (which were so predictable they can be ignored) you need a PDQ ramp up of supply. "

    TV breaks etc have historically been handled by having spinning reserve capacity on warm standby. Dinorwig eliminated some of that need by offering an extra 2GW or so supply at a few seconds notice, without the waste of energy and money involved in having spinning reserve on warm standby. Then along came the delights of "leaving it to the market".

    Nuclear thermal cannot (never will have) any meaningful load following capability on any meaningful timescale. Physics and metallurgy says so, even if the industry spinners won't admit it. Dinorwig used to be an interesting place to enable nuclear stations to not have to load follow, that doesn't really apply this century. Anyone knows otherwise, please show your facts and your sources.

    If readers want to see where the UK's electricity comes from, live hour by hour and for the last year or so, it can be done easily. E.g. at

    http://www.gridwatch.templar.co.uk/

    During the 2019 outage mentioned earlier, the first serious symptoms showed when grid frequency fell to 49.1Hz, way below expected values, recovery measures then kicked in leading to a recovery to 49.2 Hz within 30 seconds or so, but then the chaos resumed and within 30 seconds or so the frequency had fallen again to below acceptable limits leading to further recovery measures, during which the frequency fell to 48.8Hz. Read it and weep.

    From Gridwatch right now 0100 Friday): grid frequency 49.982Hz, demand 25.8GW

    Nuclear: flatlined at 4,5GW or so, where it has been for the last 12 months or so. Before that, from memory it often sat at roughly 6GW for long periods of time (check the numbers if you want).

    CCGT: 12GW of valuable petrochemical feedstock going up in smoke.

    Solar: Peaked at 5GW at midday, closely matched by a reduction in CCGT. Currently zero.

    Wind: Currently 6GW, having ramped up from zero around 8am on Thursday

    Whether anyone will want to be paid large sums n GBP rather than in Euro a few years from now is a different question. But that's years away, so who cares.

    ================================================================================

    From https://eciu.net/insights/2019/powercut-a-10-year-failure-to-act

    "[these protection systems] work either by sensing the rate at which the grid frequency is falling – ‘Rate of Change of Frequency’, or ‘RoCoF’ – or by a shift in the phase of the electrical waveform – ‘Vector Shift’ or ‘VS’.

    In the 2008 event, both types of system were activated by the change in frequency and phase in the national network caused by the Longannet and Sizewell outages. In shutting down, they made the problem worse.

    Investigating that incident

    , National Grid detailed its ‘…concern that embedded generation protected by Rate of Change of Frequency (RoCoF) protection could trip following a large generation loss. The effect of such RoCoF trips could aggravate the resulting frequency change following the loss and have an adverse effect on normal frequency recovery.’

    To adapt a phrase invented by one long-term industry professional: overly sensitive RoCoF and VS transformed the fall of a single cyclist into a collapse of the whole peloton.

    ======

    Sources are quoted and linked if you want them.

  16. Potemkine! Silver badge
    Headmaster

    "1.41GW of energy"

    Watts are not for energy, they are for power. Joules are for energy.

    == Bring us Dabbsy back! ==

  17. ShortStuff

    Gimme more money!

    This is totally stupid. The water power they are talking about is too distributed and would cost way way way too much to try to harness. They are just trying to get some taxpayer funded government grants to fuel their career and retire on. Now if they wanted to really harness water power they should be designing a way to harness the power of the high and low ocean tides.

  18. Danmatk

    More proof phd's can't look beyond their nose

    There is no such thing as free energy. The water in all these lines has pressure for a reason. This is created by pumps.

    If you put generators in line of these pipes, you pit more resistance. Which means more pumping power is needed upstream. Stulidest thing I've read all day. They have been trying to peddle this bs for decades.

    Just shows a degree without any practical real world knowledge Is a waste.

    1. John Brown (no body) Silver badge

      Re: More proof phd's can't look beyond their nose

      "There is no such thing as free energy. The water in all these lines has pressure for a reason. This is created by pumps."

      Depends where you live Not all water deliver is pumped. I'll grant thet there is no free energy, but hydropower does actually exist. There are some big, world recognised places that have it. Hoover Dam, Aswan Dam to name but two. Now, technically that's not "free" energy since there are laws of physics describing that. But from an everyday practical point of view, it's "free" in that it's tapping gravity. The paper refers to "gravity fed" systems. There may also be places where water needs to be pumped up and over a geological feature such as hills or mountains. You ar paying to pump it up and over, so why not stick a turbine at least part way down the other side and reclaim some of the energy being imparted by gravity as the water falls down the other side? As others have mentioned, think about regenerative breaking. Why waste energy as heat if it can be recovered in a more useful form? That's what's happening as the water comes down a gravity fed pipe. It might even be that the pressure at the bottom is too high and has to be reduced. Without using a turbine to reduce the pressure and reclaim some energy, you need to use baffles and constrictors to reduce the pressure. That's the car equivalent of wasting energy by converting it to heat through break pads and disks instead of regen breaking taking the momentum back as electricity.

  19. bigtreeman

    fucking horseshit

    Water and waste water cost an enormous amount of electricity.

    Pumping, filtering, treating.

    The Reg has some dumb ass articles.

  20. Spunbearing

    Ground Based Heat Pumps

    Perhaps a better use of a giant underground network of pipes is a heat source for heat pumps that is more efficient than using air. Heat pumps are gaining popularity but the ROI on going ground based is not good in many areas. This could also be used an adjunct to an air based system for when outside temperatures reduce efficiency. A solution to the issue of limited space for horizontal systems and the cost to excavate (or drill vertical systems).

    Its likely that the real value of water in pipe is its heat energy. Two meters down the soil temp is about 11°C, and that thermal energy is available through an existing network of pipes. Imagine using cool tap water instead of 35°C air for a AC systems condenser? In the winter it works once ambient temperatures drop lower that ground temperatures.

    Spun

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