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Discussion on Spirit of Ireland Proposal

  • 07-05-2009 06:59PM
    #1
    Registered Users, Registered Users 2 Posts: 422 ✭✭


    Interesting.

    Downloads a Word document (maybe I should have cut & paste!).


«1

Comments

  • Closed Accounts Posts: 224 ✭✭Cheeble


    What's your point?

    Cheeble-eers


  • Registered Users, Registered Users 2 Posts: 2,300 ✭✭✭MayoForSam


    Eddie Hobbs was on the radio this morning and mentioned this idea, sounded like he was looking for investors. The idea does have some merit - not too many other countries have the topography to do this - Norway maybe but they have their oil reserves.

    Sounds a bit too good to be true, I am sure the planning process in this country will hold things up for years anyway. Plenty of NIMBY's would have a canary if someone suggested flooding the local valleys with sea water.

    Proof-of-concept would be required at the very least. Why can't we be pro-active in this area like the Danes were 20 years ago with pure wind? Dream on....


  • Closed Accounts Posts: 9,082 ✭✭✭lostexpectation


    get steorn feeling off these guys


  • Registered Users, Registered Users 2 Posts: 15,489 ✭✭✭✭loyatemu


    get steorn feeling off these guys

    hardly the same thing - I don't know whether what they're proposing is feasible on such a large scale, but we do alreay have wind-farms and pumped storage hydro plants in this country so the basic concepts are already proven.


  • Registered Users, Registered Users 2 Posts: 13,104 ✭✭✭✭djpbarry


    Cheeble wrote: »
    What's your point?
    Indeed. OP, please provide something more than a link to a document when starting a thread, as per the charter.


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  • Registered Users, Registered Users 2 Posts: 134 ✭✭InvisibleBadger


    A few more specifics would be nice. What valleys do they propose to flood and so on. Does seem a bit too good to be true, but if it is, i would like to see it happen.


  • Closed Accounts Posts: 50 ✭✭slagger


    MayoForSam wrote: »
    Eddie Hobbs was on the radio this morning and mentioned this idea, sounded like he was looking for investors. The idea does have some merit - not too many other countries have the topography to do this - Norway maybe but they have their oil reserves.

    Sounds a bit too good to be true, I am sure the planning process in this country will hold things up for years anyway. Plenty of NIMBY's would have a canary if someone suggested flooding the local valleys with sea water.

    Proof-of-concept would be required at the very least. Why can't we be pro-active in this area like the Danes were 20 years ago with pure wind? Dream on....

    I wonder who'll be the firsts nimby's in the queue. The Greens, maybe?

    http://www.adrianramsay.org.uk/blog/not-all-renewable-energy-projects-are-green.html

    http://www.nce.co.uk/the-severn-barrage-calling-greens-bluff/1967356.article


  • Closed Accounts Posts: 88,968 ✭✭✭✭mike65


    Pat Kennys radio programme gave this a fair wind on yesterdays programme (should be podcastable from www.rte.ie/radio1 ), it sounds like "the anwser" on the face of it, but would require quite a bit of upgrading the grid I belive.


  • Closed Accounts Posts: 88,968 ✭✭✭✭mike65




  • Closed Accounts Posts: 17 mike0001


    Steorn.com II The sequel !

    Remember that lotto ad: green hippy in the grass, "I'd buy a cloud for water...yea"

    Play lotto or it could be her!


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  • Registered Users, Registered Users 2 Posts: 2,011 ✭✭✭sliabh


    They quote a 3,000 MW capacity, and a requirement for 1% of Irish land area. I did some calculations on this using formulae from David MacKay's (free) book "Sustainable Energy Without the Hot Air". I took an average 7m/s wind speed (from Met Eireann) and a generous 35% load factor (from the Irish Wind Energy Association).

    The results come out that you can generate that sort of power, but only with enough wind farms to cover 2,500 square kilometers of land, or about 3.5% of the land area of the republic. So at least one of their numbers is BS.

    To put that in perspective, all of country Limerick is 2,686 square kilometers, and today only 1.9% of the country's land area is classed as "artificial". The scale of the project you are talking about here is beyond colossal.

    I didn't get around to looking into their pumped storage claims, but this already looks like fantasy to me.

    And that is before you start asking whether we should trash the entire western seaboard, the most rugged beautiful part of this country, with this questionable scheme.


  • Registered Users, Registered Users 2 Posts: 725 ✭✭✭lostinsuperfunk


    I get a much lower area figure of 750 km2 (still quite a lot though!):

    3000 MW will require (say) 3000 x 3 MW turbines running at 33 % capacity.
    These turbines have, say, a 100 m rotor diameter. Using the 5 x rotor diameter turbine separation rule of thumb you get an inter-turbine separation of 0.5 km, so there is one turbine in each 0.5 km x 0.5 km area, i.e. one turbine per 0.25 km2.

    By this measure, 3000 turbines will occupy 3000*0.25 = 750 km2.

    There are massive assumptions here. In particular I'm not sure about how the 5 x d thing scales for such large, high turbines.

    In any case, the actual turbine footprint is much smaller than the area of the wind farm. Only a tiny proportion of the areas of the wind farms would become artificial.


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    I love their idea but what were they thinking with the name.

    I thought it was a religious scam until I went to their website
    the other day.


  • Closed Accounts Posts: 987 ✭✭✭diverdriver


    It is pure fantasy. The investment required is massive. The Engineering required is massive. Whether it's 750 Km2 or 2500 Km2, the scale of wind farm coverage is enormous. We would be up to our ears in wind turbines. It's bad enough now in certain areas. The final killer is the idea of flooding valleys in the west of Ireland to produce hydroelectric power with sea water no less! I for one would object to that never mind the what the locals think of it.

    But even if it was a runner. Where are we going to get the money for it? It simply will not happen. All credit to them for thinking big. But we might as well be trying to organise the first Irish space mission to put solar panels in orbit.


  • Registered Users, Registered Users 2 Posts: 2,011 ✭✭✭sliabh


    Hi lostinsuperfunk,

    It is good to see someone else going into the numbers with this, because SoI seem to be very reluctant to provide theirs.

    I think the reason for the discrepencey in our answers is that the power rating for a wind turbine (e.g. 3.6MW for the 128m ones on the Arklow bank) is based on the maximum output, rather than the average. This is usually calculated around a 15m/s wind speed which is the optimum.

    So while 3000 100m turbines could generate enough power for the country, most of the time they won't, and additional units will be required.


  • Registered Users, Registered Users 2 Posts: 720 ✭✭✭Hoagy


    There was a good letter in the Independent a while ago which also poured salt water on the idea.

    The proposal is obviously very simplistic and very impractical; to say that it could be achieved in five years is mind boggling. While we are right to consider sustainable sources, renewables alone will not solve our energy problems.


  • Registered Users, Registered Users 2 Posts: 725 ✭✭✭lostinsuperfunk


    Hi Sliabh,
    The 33% capacity factor takes into account the fact that the turbines spend a lot of their time running at below maximum rated output, or not running at all.

    3000 x 3 MW turbines will have a maximum output of 9000 MW. Apply the 33% capacity factor and they produce, on average over a period of a year or longer, 33 % of their peak output, or 3000 MW.

    Re: the letter in the Indo, Prof. Walton could be accused of being very selective with his figures. He bases his calculations on the peak energy demand of 5000 MW, but this is only sustained for short periods of time. He is a known proponent of nuclear power, which I have no problem with, but he may have an agenda. I think he is missing the point here : nuclear power alone cannot meet our energy needs. Neither can wind. But the idea of large scale storage would be a big enabler for either nuclear or wind generation (or both), and interconnectors can help too.

    The area figures are a bit misleading when quoted this way. If you build a big wind farm you have to space the turbines out so that the wake of one turbine doesn't affect other turbines downwind. If we allowed our 3000 turbines a generous base area of 20 m X 20 m each, they would occupy an area on the ground of 1.2 sq. km, although they would be spread out over a much larger area.


  • Registered Users, Registered Users 2 Posts: 2,011 ✭✭✭sliabh


    Hi Sliabh,
    The 33% capacity factor takes into account the fact that the turbines spend a lot of their time running at below maximum rated output, or not running at all.

    I stand corrected, I found I double counted the load factor in my calcs.

    But while the actual ground space under the turbines may only be 1.2km^2 you will still need to account for the huge are the farms take up as pretty much no one will want to be living under or right beside them. So there will still be a struggle to find the land for all of these.
    Re: the letter in the Indo, Prof. Walton could be accused of being very selective with his figures. He bases his calculations on the peak energy demand of 5000 MW, but this is only sustained for short periods of time.

    True, but it is a demand that has to be met. And the extra capacity would probably be needed to fill the storage system in off peak times anyway.


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    The idea is relatively simple. Spirit of Ireland says that energy generated from wind farms can meet some, but not all, of the country's needs. However, wind energy could be used at off-peak times to pump water from the sea into reservoirs created from valleys on the west coast.

    quoted from the newspaper article here:

    http://www.friendsoftheirishenvironment.net/paperstoday/index.php?do=paperstoday&action=view&id=13240

    See spirit of Ireland website here:

    http://www.spiritofireland.org/

    The last time I ranted on about aspects of this, the wind company wanted to dig the insides of the mountains out and site turbines in SAC's, and now this chap has a brigher idea and cheaper too no doubt. I kind of like the valleys as they are.

    My one question is: how many valleys would it take to supply the required electricity needs at a commercially viable price?


  • Closed Accounts Posts: 224 ✭✭nayorleck114


    I was thinking of the Lough Easkey area of Co. Sligo.

    http://www.flickr.com/photos/jwallace/143651792/

    Problem is than you are always going to have some oposition to any site. Then you will have Rossport eco nerds camping and protesting.

    Anyway there are lots of valleys, you just need to make sure its one with few N.I.M.B.Y's.


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  • Closed Accounts Posts: 2,025 ✭✭✭zod


    better we flood one or two valleys here before climate change floods all of them.

    If you don't believe that, then read "The end of oil" because oil is going to 200 dollar a barrel, and we as one of the worlds most heavily dependent nations on oil are going to wish we did something while we could still raise the cash.


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    would one or two valleys do it?


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    If you want information their Presentation at the Engineers Ireland HQ
    has probably been the most comprehensive so far.

    Videos on Engineers Ireland here. (Everything on June 23rd)

    Discussion about it on SOI forums here.

    As one of the engineers at that presentation, I was quite impressed but
    a lot of people are very cynical about the whole thing. Hopefully it will
    be all cleared up when they release their updated proposal in September.

    They have quite a simple solution for the N.I.M.B.Y's. They have identified
    about 50 suitably valleys along the west coast from Kerry up to Donegal.
    If there is a lot of opposition for a site they will simply choose a different
    one.

    Edit:
    Two large valleys would probably do it and by doing it I mean supply electricity
    for several days when there is no wind blowing.


  • Closed Accounts Posts: 867 ✭✭✭gpjordanf1


    Shiny wrote: »
    If you want information their Presentation at the Engineers Ireland HQ
    has probably been the most comprehensive so far.

    Videos on Engineers Ireland here. (Everything on June 23rd)

    Discussion about it on SOI forums here.

    As one of the engineers at that presentation, I was quite impressed but
    a lot of people are very cynical about the whole thing. Hopefully it will
    be all cleared up when they release their updated proposal in September.

    They have quite a simple solution for the They have identified
    about 50 suitably valleys along the west coast from Kerry up to Donegal.
    If there is a lot of opposition for a site they will simply choose a different
    one.

    Edit:
    Two large valleys would probably do it and by doing it I mean supply electricity
    for several days when there is no wind blowing.

    Its not the N.I.M.B.Y's. i'm worried about, it's An Taisce they will do everything in their power to stop it!

    I really am in favour of this but we really need to start this project now!!


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    gpjordanf1 wrote: »
    Its not the N.I.M.B.Y's. i'm worried about, it's An Taisce they will do everything in their power to stop it!

    I really am in favour of this but we really need to start this project now!!

    I think they would be more opposed to the 4000 or so wind turbines
    that need to be built to fill the lakes.

    There seems to be far less opposition to the storage element of the proposal which
    I think is by far the most important.


  • Registered Users, Registered Users 2 Posts: 13,104 ✭✭✭✭djpbarry


    Threads merged.

    I've edited the title to make it a bit more general.


  • Closed Accounts Posts: 867 ✭✭✭gpjordanf1


    Shiny wrote: »
    I think they would be more opposed to the 4000 or so wind turbines
    that need to be built to fill the lakes.

    There seems to be far less opposition to the storage element of the proposal which
    I think is by far the most important.

    Where did you get 4,000 from?

    Having re-read the merged thread (correct me if i'm wrong) but people seem to be calculating the energy requirements of the country based on Wind Farms, where in fact they are only using wind to pump water to fill and top up reserivors, which I would imagine wouldn't need that much wind turbines?


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    I didn't get that number from the thread but I will have a look to
    see where I got it from.

    Igor, mentions 2000-3000 here but I'm almost certain I read
    that the number would be closer to 4000.

    This number would be in addition to existing wind farms including those at Gate 3.

    Their plan seems to be that these turbines do nothing other than constantly top up the
    storage lakes. Many of these wind farms would be owned by local Co-Ops who would sell
    their electricity to SOI (or whatever entity) for a lower (than current wind farm) price but
    with the guarantee that they will never have to curtail their output. It hasn't happened yet (in ireland)
    but as the installed wind capacity exceeds 15% we will start to hear about it more and more.


  • Closed Accounts Posts: 867 ✭✭✭gpjordanf1


    Shiny wrote: »
    I didn't get that number from the thread but I will have a look to
    see where I got it from.

    Igor, mentions 2000-3000 here but I'm almost certain I read
    that the number would be closer to 4000.

    This number would be in addition to existing wind farms including those at Gate 3

    Having a look at their site again, wind power will only be used for pumping of water and not connection to the grid, Hydro only connected to the grid, so again I cant see how that many would be required?


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  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Shiny wrote: »
    This number would be in addition to existing wind farms including those at Gate 3.

    good. the more the better


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    gpjordanf1 wrote: »
    Having a look at their site again, wind power will only be used for pumping of water and not connection to the grid, Hydro only connected to the grid, so again I cant see how that many would be required?

    It all depends on the size of the Turbine chosen.

    If they are allowed build lots of 3MW+ size Turbines then
    the number will be less for sure.

    They are also being extremely pessimistic with all their numbers by
    giving the "worst case" figures.

    Edit, I'm going to look at the videos now and get an exact number.

    Edit 2, ok he mentions 2,500 turbines in the introduction presentation so
    that must represent the 1.5MW grade turbines.


  • Closed Accounts Posts: 867 ✭✭✭gpjordanf1


    Shiny wrote: »
    It all depends on the size of the Turbine chosen.

    If they are allowed build lots of 3MW+ size Turbines then
    the number will be less for sure.

    They are also being extremely pessimistic with all their numbers by
    giving the "worst case" figures.

    Edit, I'm going to look at the videos now and get an exact number.

    Edit 2, ok he mentions 2,500 turbines in the introduction presentation so
    that must represent the 1.5MW grade turbines.

    Either way I'm all for it and if I owned land with a usable valley I would be camped outside their door!
    So September is the big presentation, not long to wait, heres hoping the right people get behind this?
    To think these people are devoting their time, money and energy into solving the majority of this country's problems and then you think of our government are going to take 11-12 weeks holidays without so much as a second thought, amazing when you think about it!


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    I'm depresed about the amount of time it will take to get planning permission though. 10 years is conservative and probably just enough for everyone to lose interest.

    There will be no fast track, no politician has the cahoonas.

    The Scots will be beat us to it : http://www.theherald.co.uk/news/news/display.var.2517244.0.Hydros_potential_to_power_all_Scots_homes_in_a_decade.php


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    The "Pumped Hydro Energy Storage to Support Wind Energy Penetration in Ireland" April 2006 publication by The Sustainable Energy Research Group, University College Cork

    http://216.239.59.104/search?q=cache:priYqXWpKTwJ:www.ucc.ie/serg/pub/PS-R2.pdf+wind+energy+storage+hydro&hl=en&ct=clnk&cd=2&gl=ie

    finishes by saying:

    "Further work is to be carried out on the economic impacts of pumped hydro energy storage. As the liberalised market operation and parameters are as yet uncertain, it is difficult to quantify definitively the benefits of installing such a system."

    If we are to have 2-4000 turbines along the west coast, is the proposed storage system the most efficient use of the energy produced. I recall, but cannot pin it down, that there is somewhere betweer 30-40% losses between production by turbines and final output from the hydro stations. Surely a direct connection to the grid is a better idea for thses turbines with some other alternative such as biomass stations to take up the slack when needed. Is it proposed to put the turbines offshore?


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Oldtree wrote: »
    If we are to have 2-4000 turbines along the west coast, is the proposed storage system the most efficient use of the energy produced. I recall, but cannot pin it down, that there is somewhere betweer 30-40% losses between production by turbines and final output from the hydro stations. Surely a direct connection to the grid is a better idea for thses turbines with some other alternative such as biomass stations to take up the slack when needed. Is it proposed to put the turbines offshore?

    1. They hope to to get 87% efficiency from the pumped

    2. They can still divert power from the windfarm straight into the grid at 100% efficiency ( what did you think they do when the resevoir is full ?)

    3. The pumped storage is the central idea of the Spirit of Ireland otherwise it would be called "Lets use the wind" and is crtical in selling power at the best time (premium rate)
    Oldtree wrote: »
    Is it proposed to put the turbines offshore?

    Did you even read the proposal ?


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  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    1. hope springs eternal............ 87% is way up there with the fairys!

    2. not just my opinion see further up this thread
    Shiny wrote: »
    Their plan seems to be that these turbines do nothing other than constantly top up the
    storage lakes.

    3. I had interpreted that the turbines were the central issue and the pumped storage secondary.

    4. should have said " put turbines offshore in addition to the land based ones........."


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    Oldtree wrote: »
    The "Pumped Hydro Energy Storage to Support Wind Energy Penetration in Ireland" April 2006 publication by The Sustainable Energy Research Group, University College Cork

    http://216.239.59.104/search?q=cache:priYqXWpKTwJ:www.ucc.ie/serg/pub/PS-R2.pdf+wind+energy+storage+hydro&hl=en&ct=clnk&cd=2&gl=ie

    finishes by saying:

    "Further work is to be carried out on the economic impacts of pumped hydro energy storage. As the liberalised market operation and parameters are as yet uncertain, it is difficult to quantify definitively the benefits of installing such a system."

    If we are to have 2-4000 turbines along the west coast, is the proposed storage system the most efficient use of the energy produced. I recall, but cannot pin it down, that there is somewhere betweer 30-40% losses between production by turbines and final output from the hydro stations. Surely a direct connection to the grid is a better idea for thses turbines with some other alternative such as biomass stations to take up the slack when needed. Is it proposed to put the turbines offshore?

    A direct connection to the grid with that many turbines would never
    work without storage. 2000 Turbines alone would potentially produce
    in excess of 3000MW in strong wind conditions. This would be fine if
    it occurred on a cold winter afternoon at peak demand but what would
    happen if it continued into the middle of the night when the demand
    for the whole country goes below 3MW ?

    They are not against the turbines being built offshore but until such a
    time that it becomes affordable to do so, there wont be any plans to
    build them. Those new floating turbines look interesting but are only
    in the testing phase at the moment.
    zod wrote: »
    2. They can still divert power from the windfarm straight into the grid at 100% efficiency ( what did you think they do when the resevoir is full ?)

    Watching Alan Mulcahy's presentation I got the impression that they would try to prevent the
    reservoirs from becoming full as much as possible due to the fact that the grid would not be
    able to take the excess wind.

    They would only be generating electricity at peak times to get the best price but also because
    it wont be wanted at other times.


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Shiny wrote: »
    A direct connection to the grid with that many turbines would never
    work without storage. 2000 Turbines alone would potentially produce
    in excess of 3000MW in strong wind conditions. This would be fine if
    it occurred on a cold winter afternoon at peak demand but what would
    happen if it continued into the middle of the night when the demand
    for the whole country goes below 3MW ?

    Look, if during peak demand you wanted to divert some of power from the windfarms straight into the grid at 100% efficiency then you can. The rest goes to the pumps. Its not all or nothing.

    Also the plan calls for interconnects to Britain so that we can sell electricity at premium rate .. when we have too much or their wind dies or if they need the green credits.

    This plan turns eratic wind energy into baseload .. the holy grail for green energy and highly sought after in Europe where they would kill for this kind of geographic advantage. What do want us do .. wait for oil to go to €400 / barrel or the planet to go beyond the tipping point ?


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Oldtree wrote: »
    1. hope springs eternal............ 87% is way up there with the fairys!

    What do you base this on ? Please link to any source

    quote : "Taking into account evaporation losses from the exposed water surface and conversion losses, approximately 70% to 85% of the electrical energy used to pump the water into the elevated reservoir can be regained.[1] The technique is currently the most cost-effective means of storing large amounts of electrical energy on an operating basis"

    Taken from http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    zod wrote: »
    What do want us do .. wait for oil to go to €400 / barrel or the planet to go beyond the tipping point ?

    eh...no :rolleyes:

    I was just trying to highlight the importance of the storage to
    Oldtree.


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  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    I like the floating wind turbine idea, it would really minimise the impact on the sea floor. Maby they could attach some sort of wave generator to it to boost its performance.

    What I want is a real sustainable and balanced approach. Not one that will destroy our precious enviromental reserves. There is a need for so called renewable energy, but at what cost are we prepared to move foraward with this. I bow to the democratic will of the people. The valleys all have their own unique value and that must also be taken into consideration. They are not just useless areas of land consigned to the dung heap.


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    from above: The "Pumped Hydro Energy Storage to Support Wind Energy Penetration in Ireland" April 2006 publication by The Sustainable Energy Research Group, University College Cork

    http://216.239.59.104/search?q=cache...lnk&cd=2&gl=ie

    "The round-trip efficiency of such a system is generally in the order of 70-80%"

    from the Spirit website:

    Question: What is the energy storage efficiency of hydro storage plant compared to other forms of energy storage?
    Answer: Hydro Storage is the most widely used grid energy storage system. It is a robust, mature technology. Modern plant has good round trip efficiency of up to 84%. Large storage capacity can be constructed at acceptable cost. Alternative storage systems tend to be either less efficient or more expensive.

    Batteries store electric charge as chemical energy. They are the oldest known form of storage. Many different types are now available in addition to the well-known lead acid batteries used in vehicles. The typical round trip efficiency for batteries ranges from 89 to 92 %. Sodium sulfur batteries are one of the more promising technologies being considered for grid storage duties. However, they cost much more than Hydro Storage. Recently, super capacitors have been investigated. These have very high efficiencies of 97 to 98% but are very expensive and unsuitable for large-scale storage.

    Compressed air stored under pressure in sealed mines or tunnels has been used with pneumatic compressor turbines. Suitable sites for large scale storage present considerable engineering challenges. Few are operating. These stores have low round trip efficiency of about 70%.

    Large flywheels suspended on magnetic bearings to minimize friction losses have been tested to store mechanical energy. These have good efficiency of 90% but are costly and have only been tested on a limited scale. Experiments carried out with super conducting magnetic energy storage devices have demonstrated efficiencies of 95%. These are based on low /zero resistance superconductors, which have been under development for many years but are not yet commercially available. Pilot schemes producing hydrogen by electrolysis from water are being tried in Germany. The hydrogen is later used as a fuel for vehicles or to produce electricity. These are currently around 50 to 69% efficient but improvements are expected from new electrolyser technology. Large scale exploitation is likely to be many years away.


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Oldtree wrote: »
    Hydro Storage is the most widely used grid energy storage system. It is a robust, mature technology. Modern plant has good round trip efficiency of up to 84%. Large storage capacity can be constructed at acceptable cost. Alternative storage systems tend to be either less efficient or more expensive.

    eh? so we are agreed then .. the pumped storage idea of "spirit of Ireland" is probably the best approach to store energy and it's efficiency claims are not "up there with the fairies"


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    erm.:confused:.. no I don't think we are agreed.

    I was showing that the 87% you stated was down to 84% on the spirit website and in the UCC 2006 publication it was down to between 70-80% efficient. This efficency scale of over 20% losses represents a huge amount of energy wasted, notwithsanding leakages from the resevoir.

    This fellow seems articulate and educated have a read of his article:

    http://sustainability.ie/pumpedstoragemyth.html


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    This 2004 report from the SEI varies with the UCC 2006 report. Which is right?

    http://www.sei.ie/Grants/Renewable_Energy_RD_D/Projects_funded_to_date/Wind/Study_of_Elec_Storage_Technologies_their_Potential_to_Address_Wind_Energy_Intermittency_in_Irl/

    Pumped hydro energy storage (PHES) is a mature and familiar technology and
    has been utilised within electricity systems for many years. It is the most
    widespread energy storage system currently in use on power networks, operating
    at power rating up to 4,000 MW and capacities up to 15 GWh. PHES uses the
    potential energy of water, transferred by pumps (charging mode) and turbines
    (discharge mode) between two reservoirs located at different altitudes. Currently,
    the overall efficiency is in the 70-85% range although variable speed machines are
    now being used to improve this. The efficiency is limited by the efficiency of the
    deployed pumps and turbines (neglecting friction losses in pipes and water losses
    due to evaporation). Plants are characterized by long construction times and high
    capital costs. One of the major problems related to building new plants is of an
    ecological/environmental nature


  • Registered Users, Registered Users 2 Posts: 2,259 ✭✭✭Shiny


    We should find out what the efficiency will be in September as
    I assume by that time they will have provisionally chosen the
    hydro turbines to be installed, narrowed it down to a specific
    site etc...


  • Closed Accounts Posts: 13 extremeweather


    I have seen a German publication from 1998 which presents the efficiency of each component of a typical pumped hydro plant and multiplies them together to get a round trip figure of 77.3%. This might have improved slightly in the last ten years but 87% seems very ambitious.


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    Also at this website

    http://www.sustainability.ie/payback.html

    the following is stated:

    "The energy required to manufacture some micro wind turbines, notably the Windsave model which is intended for mounting to buildings, is probably considerably more than the equipment could generate over its operating lifetime in most real world situations! Such equipment is probably a net energy loser."

    While there is financial payback from many of the renewable sources over a(debatable) number of years, I have often wondered about the pollution aspect of unit production verses the pollution saves by the operation of the unit, which is excluded from the actual unit cost and by the use of grants. Would it be fair to include the emmissions from the factory workers car on his/her way to work in any assessment of pollution for this purpose, waste streams, etc?

    Has this been quantified for the massive industrial turbines and are we on a false economy with regard to actual pollution. In fact if this is true then we are polluting now as against polluting over a (debatable) number of years?

    Many manufacturers are pushing the so called pollution free aspect of their products!

    I would be very interested in any links to actual data as I cannot seem to get a good search wording to find this out.


  • Closed Accounts Posts: 2,025 ✭✭✭zod


    Oldtree wrote: »
    "The energy required to manufacture some micro wind turbines, notably the Windsave model which is intended for mounting to buildings, is probably considerably more than the equipment could generate over its operating lifetime in most real world situations! Such equipment is probably a net energy loser."

    The idea of comparing a MICRO turbines effiency ( the ones that fit on your roof ) to a large industrial turbine is laughable

    I believe that is listed as myth no.3 here

    With regard to the efficiency of the pumps it actually doesn't matter too much as long as you are using the most effiecient use that is achievable for a realistic cost .. as you yourself quoted :
    Question: What is the energy storage efficiency of hydro storage plant compared to other forms of energy storage?
    Answer: Hydro Storage is the most widely used grid energy storage system. It is a robust, mature technology. Modern plant has good round trip efficiency of up to 84%. Large storage capacity can be constructed at acceptable cost. Alternative storage systems tend to be either less efficient or more expensive.

    So we can can now use circa 80% the winds night electricy durring the day and charge the Brits top dollar for it. Its a no brainer.


  • Registered Users, Registered Users 2 Posts: 8,109 ✭✭✭Oldtree


    Zod that was a very interesting link, thank you. I was not making a comparison but asking a question, I await to be enlightened.

    I think that on your link they are referring to comparrisons of actual financial costs (or energy consumption in the production) as against the actual real pollution emitted by production vs pollution saved by a large turbines use (instead of say a coal/gas fired elec station) is what I was referring to. also the statement is on a vested interest site (as maybe the statement on the sustainability website is). actual figures of pollution comparrisons which is what I was trying to find.

    nonetheless I am trying to find a copy on the web of

    Milborrow, Dispelling the Myths of Energy Payback Time, as published in Windstats, vol 11, no 2 (Spring 1998).

    which is the publication to which they got this nugget from to see exactly what "costs" are covered in this statement


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