El Hierro October 2016 performance update

During October the hybrid wind-hydro Gorona del Viento (GdV) plant achieved 19.8% renewables generation, higher than the 13.5% achieved in September 2015 but barely a third of the 58.2% achieved in August 2016. The cause was an abrupt mid-month degeneration in wind conditions (renewables generation averaged 32.4% in the first half of October but only 7.7% in the second, and for a total of 199 hours during the month GdV generated no electricity at all). Percent renewables generation since full operations began at GdV in June 2015 now stands at 38.8%, down from 40.1% at the beginning of the month. This represents only 8.9% of El Hierro’s total energy demand if we accept that electricity supplies only 23% of El Hierro’s total energy. Data on GdV plant layout, operation and capacities are given in the September 2015 review. Previous posts on GdV are accessible through the El Hierro portal

Figure 1 plots daily average percent renewables generation since project startup on June 27, 2015 (data from Red Eléctrica de España (REE). The abrupt decrease in renewables generation in October 2016 is apparent:

Figure 1: Daily mean percent renewables generation since June 27, 2015. The monthly divisions are approximate

The following Table updates the monthly grid statistics. Note that a column showing GdV generation as a percentage of El Hierro’s total energy demand has been added. The numbers in this column assume that electricity generation fills 23% of El Hierro’s total energy demand in each month, which is in line with the 20% estimate published in a pie-slice chart by Climatique for all the Canary Islands. The 23% estimate is, however, not verified, so the numbers in the column are italicized to signify uncertainty:

Figure 2 plots the REE 10-minute generation data for October. Surplus wind is still being wasted by pumping water uphill and hydro is still being fed to the grid in small quantities. There were no periods of 100% renewables generation during the month:

Figure 2: 10-minute REE grid data for El Hierro, October 2016

Figure 3 compares 3-hour wind speed readings at El Hierro airport with GdV’s total wind generation during October (10-minute data). In this case wind generation is perhaps not as high as the airport wind speeds suggest they should be in the second half of the month, and the most likely reason for this is changes in wind direction. Wind directions were dominantly northerly in the first half of the month but ranged over all points of the compass in the second, with frequent rapid changes in wind speed. Periods of higher wind speeds and higher wind generation during the second half of the month also tended to correlate with periods of northerly, and in some cases southerly winds, indicating that the GdV wind turbines, which are aligned east-west on a ridgetop, perform more efficiently when the wind comes from the north or south.

Figure 3: Gross wind generation versus wind speeds at El Hierro airport, October 2016


There is little to discuss here other than to speculate on what the wind might do in November. Accordingly I have performed a brief analysis of wind curtailment, the results of which are discussed below.

Wind curtailment at GdV occurs in two stages. The first is curtailment above the thresholds that have been adopted to maintain grid stability, which are generally in the 5-7.5MW range but sometimes lower. It is not possible to estimate how much wind power was curtailed above these thresholds, but in windy months like July 2015 it would have been substantial:

Figure 4: GdV wind generation, July 2015. Wind is curtailed to an unknown extent above all the flat-topped intervals

The second curtailment stage involves wasting surplus wind power by using it to pump water uphill and allowing the water to flow down again without generating any electricity in the hydro plant, meaning that the hydro pumping circuit is functioning as a dynamic resistor. Here the wind losses can be estimated from the REE grid data, and the results by month are summarized in the Table below. The wind power used to produce hydro power is calculated assuming that the hydro system is 60% efficient:

Average pumping curtailment has been 30.4% since project startup. It’s easy to see how the curtailment added by generation thresholds such as those shown in Figure 4 could have increased total curtailment to 50% or more in some months, but unfortunately it’s not possible to come up with hard numbers.

Finally, Figure 5 plots percent pumping curtailment against total monthly wind generation since project startup. Curtailment increases with generation, as we would expect, and at a fairly high level of correlation (the R squared value of the trend line is 0.77).

Figure 5: Percent pumping curtailment versus total wind generation by month since June 27, 2015

This entry was posted in Energy and tagged , , , , . Bookmark the permalink.

89 Responses to El Hierro October 2016 performance update

  1. Greg Kaan says:

    Usual nag to add to the portal 🙂

  2. Thinkstoomuch says:

    Roger, I really do admire your ability to follow this project. And of course to present the facts as the appear or using your ability’s to derive stuff from what is not said.

    An envious,

  3. Andre says:

    Thank you for providing the information that allows an intelligent non-specialist to be able to drill down through this stuff.

    In keeping with the modern trend there would be no harm in providing a TL:DR (what used to be called an ‘Executive Summary’).

    I suggest:-

    “Bullshit (the expensive variety)”

  4. rafael says:

    Good job Euan.

    What do you think of the other inminent proyect “chira-Soria” on the island of Gran Canaria?
    Another Hydro “battrery” versus other batteries like Lithium or vanadium…



    • Roger Andrews says:

      Chira-Soria was discussed here:


      Like GdV but much bigger.

      • rafael says:

        But since then the proyect has undergone mayor changes, since the “owner” is now REE and, as operator (not generator), chira-Soria is now qualified as “regulation proyect” (not storage). The have changed relevant aspects and is now being review by the public, in order to get final permission next year. According to REE the costs is 320m€. ¿how much storage can you really get with other technologies with that amount? (without the hydro inefficiency and hustle).

        Just recently REE just finished construction of a new electric subestation (66-220kv) called Santa Agueda, with a cost of 54m€. One of the reason for that being is the future implanteation of the Chira-Soria Proyect.



        • I went through the REE press release


          and found that the only things that had changed since I wrote the Chira-Soria post were:

          *Capital costs had increased from 300 to 320 million euros

          *A desalination plant is going to be built to supply fresh water to the reservoirs.

          The capacity of Chira-Soria remains at 5,000MWh, enough to supply Gran Canaria for only 25 hours at full (200MW output). This capacity will be useful for balancing daily load fluctuations, but over 100 times as much would probably be needed to store the energy required to fill island demand during the September – December windless period. Those who think Chira-Soria is the first step on the road to a 70% renewables future for Gran Canaria are going to be sorely disappointed.

          Regarding costs, 320 million euros for 5,000MWh of storage capacity represents 64 euros/installed kilowatt. This is about twice the estimated cost of the 30GWh Coire Glas pumped hydro project in Scotland, i.e. not cheap.

          • rafael says:

            As far as I know, REE has changed from 2 turbines to 4, in order to achieve more flexibility. Same power, more costs (seems the proyect has gone up 20m€).

            I don´t know details but twice the cost of Coire Glas, seems spaniards are not getting a bargain (at least not the tax payers), nevertherless the running costs.

            I was thinking more in other technologies of storage. Any battery system has two advantages compare to hydro/pumps, one they are scalable (now 10Mw, tomorrow, perhaps cheaper/better another 30 or 50 Mw, and so on). And two, the can be places almost anywhere, avoiding impacts and distributing through the grid where most needed (perhaps a better choice).

          • OpenSourceElectricity says:

            My point of view is that for daily energy consumption solar would fit much better for the canary islands, while wind would fit good to produce desalinated water which can be stored for months without much problems. this would be economical if the LCOE costs for wind are lower per kWh produced than fossil power production (diesel et al).
            A high up sorage for salt water providing pressurised water for desalination purposes could also store energy, if it could be built in a sufficiently safe way. (this would remove the pump/generation losses of pumped storage – the salt water must be pumped up to around 60-80 bar anyway, it does not matter if it is gouing at once to the membrane filter or is temporarily sent 600-800m uphill before being used.)

  5. Flocard says:

    I noticed that the spanish government of PP which barely passed through the parliament’s vote last week, depends crucially on the support of a political formation of the Canarias.
    I thus suspect that spanish public money will continue to flow without much critical evaluation to these islands, to El Hierro and to Gorona del Viento.
    It is reasonable to expect that the substantial financial allowance approved last may 2016 for the meager electric production of 2015 is going to increase when it comes to reward the production of 2016.
    W’ll know that next May if the government holds to that date.

  6. Al says:

    Is the monthly generation chart correct? It is stating that El Hierro generated 1352 MWh of renewables on the month of April? Around 45 MWh a day?

  7. Al says:

    Can someone explain the difference between % electricity generation and % of total energy demand? Are they not the same?

    • Euan Mearns says:

      In Europe we have three main consumers of energy 1) electricity generation 2) space heat (normally nat gas) and 3) transport fuel (gasoline, diesel and jet fuel). In El Hierro, 23% used for electricity is a very low number.

    • Rainer says:

      Yust look at your monthly bills and you see a big difference between electricity only and your personal energy bills. Think about your petrol bills to. Of course it is a little more complex in a island or in a country.

  8. Roger, as per usual, thanks again for all the effort you put into this …

    but … ” if we accept that electricity supplies only 23% of El Hierro’s total energy.” … your wording seems to suggest the question I also have …

    only 23% ?

    what are they spending the rest of their primary energy on ? … heating ? … transport ? ..

  9. ducdorleans says:

    thanks !

    (read over it … shame on me !)

  10. I’m considering writing a summary of El Hierro’s adventure with 100% renewable energy in Dutch, and maybe submit it to a newspaper or two over here …The difference between that “100% renewable energy” and reality is so breathtaking (at least for me), and I doubt anybody here, apart from a few, know anything about it …

    conditions – on geography, weather, population density, etc., that are as good as they can get, and then this rather futile result …

    of course, since Roger, Euan, Rainer et al. have already done all the numbers, I would like to use them for that part … before anything “goes public” – 🙂 – , I intend to send them a translation for remarks and other corrections …

    I’m doing some preliminary research now …

    a question that comes to my mind since I come to realise that a (substantial?) part of the El Hierro energy consumption goes to desalination, is whether any (simple) hydro has ever been considered ? … this would be 1 of the first things I would consider to build, but of course, I do not know enough of local conditions …

    El Hierro is not arid, and a few dams would provide sweet water for domestic use and agriculture, and maybe electricity … but I can’t find any “embolsa’s” or “presa” on the map

    does El Hierro has any hydro(electric) dams ? … or planned ? … anybody any information on that …

  11. fyi …

    if one has the time, and the “ganas”, the http://www.aguaselhierro.org/ link, given by Rainer yesterday, has information about El Hierro’s geology, hydrology, economy etc. to get you comfortably through the Western European winter …

    for us more north, potable water is not a problem … just open the faucet … but for Herreños, it is serious business !

  12. Rainer says:

    Critical Observation of REE-Data and the calculation in %
    Source: https://demanda.ree.es/movil/canarias/el_hierro/total

    2016-11-08 10:50 Real demand 5.1 MW
    2016-11-08 10:50 Diesel: 3,4 MW
    2016-11-08 10:50 Eólica 7,1 MW
    2016-11-08 10:50 Hidráulica: -5,3MW

    In the graphic of same time REE says: Diesel 32% Eólica: 68%
    How that is possible if Eólica is 7,1 MW and demand is 5,1MW?

    My try of explanation:
    Think that % in the graphics do not make any sense at all or the base is not demand but production.
    Somebody better explanation???

    • ducdorleans says:

      Rainer, my try …

      production = diesel + wind = 3,4 + 7,1 MW = 10,5 MW

      production at that moment is user for : real demand + punping water uphill = 5,1 + 5,3 MW = 10,4 MW

      thus all losses are 0,1 MW

      that all supposes that at that moment, there is sufficient water in the lower reservoir, and the upper reservoir can receive it …

      and why is it not “production = wind = 7,1 MW … consumption = real demand + pumping uphill = 5,1 + 2,0 (or 1,9) = 7,1 MW or similar ? … my guess is that they have 50 hz synchronisation problems with wind as sole source of production going to demand …

      • Rainer says:

        Duc, your guess is true.
        I call it the world biggest kids waterworld.
        Still waiting the tourist office to blow it at the world.
        “Island with the largest kids water world ever…….”
        Or let us say:
        Water running around and arount to put energy in the orbit.

      • Kees van der Pool says:

        Duke, you wrote: ‘my guess is that they have 50 hz synchronisation problems with wind as sole source of production going to demand”

        If wind were the sole source, you would be right. The windmills do not participate in inertial response or primary regulation and the grid would collapse.

        Inertial response is supplied by the diesel plant, the hydro generators and the synchronous pumps if they are turned on (not the two big inverter driven pumps).

        When the diesels are turned off, frequency regulation falls to the hydro generators who also supply control energy (regelenergie). The inverter driven pumps participate in the primary regulation by balancing the (random) wind input+hydro with varying grid demand+pumping.

        For an explanation of the role of the hydro generators (Peltons), see this paper:



        Elections are upon us, today/tonight will be interesting, to say the least.

        • OpenSourceElectricity says:

          Well the windmills in El Hierro provide inertia and do frequency regulation, as can be seen by the test runs with wind poer only from the island, as well as from the technical descriptions of the turbines.
          Problem is still that the hydropowerplant is mainly nothing more tahn a expensive dynamic resistor.

          • OpenSourceElectricity says:

            Here some further document. With the turbines usually more or less curtailed in El Hierro, reacceleration should not be a real problem, since the output of the wind power generation can be increased when it was curtailed before: http://spectrum.ieee.org/energywise/energy/renewables/can-synthetic-inertia-stabilize-power-grids

          • Kees van der Pool says:

            Open, the windmills on El Hierro do not provide frequency regulation. Frequency is maintained by either the diesels or the hydro plant or a combination of both.

            Far from being just an expensive ‘dynamic resistor’, the hydro plant also maintains grid frequency @ 100% wind and, even at the reduced water volume in the reservoirs, is a large 50 GWh ‘battery’.
            You did get the ‘expensive’ part right.

            What you describe as ‘re-acceleration’ is actually curtailing the power output by a certain percentage from available (wind) power. This done to have some reserve to assist the grid in maintaining frequency, just like any other governor-controlled generator. Ireland is an example where there is a large RE component.
            The El Hierro windmills are ‘limited in maximum output’ for stability reasons which is not the same as ‘curtailing’ over the whole output power range.

            If you are truly interested, the below link spells it all out – pay attention to ‘B’:

            “B. Primary and secondary control
            Wind turbines and other forms of renewable energy sources are generally ex empt from delivering primary or secondary control [10]. Together with their lack of inertia, replacing
            conventional generation with renewables will highly influence the frequency response. Not only the ROCOF is increased as explained in the previous section, also the minimum/maximum frequency is changed. Due to the lower system inertia, the remaining synchronous generators have now less time to react”


            also interesting:


          • OpenSourceElectricity says:

            Kees, please start reading the fine research material e.g. provided by VDE about this topic. Or the piles of other material.
            You already say that the windmills in ireland contribute to frequency stabilisation like any other power producer.
            There are just a few differences between the systems which must be understood, none of which hinders wind power to provide inertia or frequency control. This is described in the documents you reference as well. Please read them carefully. (The E70 already provide the possibilities described in your article if you take a look in their specification. It’s a software feature, no changes in hardware neccesary)

            For classic scnchronus generators you have a power output which is usually roughly 2% below the output the steam pressure would allow at the time, this difference should be higher in smaller grids, in local grids with diesel generation with 100…500kW it is around 30%.
            The reaction of the generator on frequency and voltage chandes ar fixed in iron and copper and can not be changed. If more power is needed it needs some seconds to adjust turbines to get the last percent of available power, and a longer time to ramp up power generation to maximum capacity. This can be bridged by extracting power from the inertia of the generator, but the amount which can be extracted by Hz of frequency loss is fixed in the iron and copper, and limited by the mechanical stability of the turbine+generator set. A mayor electric fault in direct neighbourhood of the generator can make your turbine generator set fly into the neighbourhood if things go really wrong (exceeding mechanical limits) which fortunately rarely happens, tha last time I remember happened in the 1950’s in germany.

            With wind power generation this is somehow the same, somehow different.
            In the case of a classical power generation nameplate capacity and actual capacity are the same usually, the catual capacity of the wind power generator is limited by the available wind. So if the grid stability is concerned, the “size” of the power station is variable. Which is making things more complicated, but which is not a real problem as far as short time grid stability (Minutes, so voltage and frequency control) are concerned.
            What is a benefit of the wind power generators, is that they can ramp up to the maximum (actual) capacity within seconds. much faster than a conventional powerplant (unless it operates tha boiler always at full throttle and regulates by blowing most of the stam in the condensor), similar to the diesel genertor sets we regularly build.
            As far as inertia and frequency control are concerned, the useable inertia of the wind turbine is higher than the inertia of the synchronus generator, since the rotatio speed can drop independent of the output frequency.
            So the inverter of the wind power system (4. Generation like the Enercon 70) can release more energy (J) than a synchronus generator per MW installed than a synchronus generator set fo keep frequency stable. And it can react faster, and can release it in a programmed way, not fixed in copper and iron like the synchronus generator set.
            All of these are clear advantages when grid control is concerned.
            There is only one drawback: the maximum current the inverter can deliver is limited by the thermal capacity of the installed equipment. And usually this current is smaller than the current a synchronus generator can deliver in the first fraction of seconds, being only limited by mechanical stability, and electromechanical layout.
            This leads to the result that the wind power generators contribute less peak power to frequency control, but can sustain this cntribution a longer time due to the higher available inertia.
            But this can be influneced by the design of the system. If you’d attac the inverters of a E141 to the generator of the E70, this would be a working system, but result in a maximum current which would exceed the maximum current of a conventional synchronus generator.
            But it would be more expensive also.
            The biggest difference is that with wind power generation you get a new question for the grid codes: How do you want the generators to react to support voltage and frequency. With synchronus generation you have little influence on this, beside adding a little more rotating mass or not. So this question is usually missing in the grid codes – or the non synchronus generation was required not to react at all, to avoid answering this question. Both is not possible any more today.
            The Wind power generators – gen4 for sure, to a lesser degree Gen 3 also can deliver what is needed by the grid. but they need to know what is required, and be built accodingly. (Same applys with photovoltaic inverters if capacitors are added in sufficient amounts)
            Here I see the problems in el Hierro. I am not sure if GDV knows what they should want the wind power generation to do, and if they allow the wind power systems to support the grid the way they could do.

          • Kees van der Pool says:

            Open, I read the ‘fine research’ all the time. You wrote:

            “This can be bridged by extracting power from the inertia of the generator, but the amount which can be extracted by Hz of frequency loss is fixed in the iron and copper”

            You are entirely correct. This is what happens with synchronous generators directly coupled to the grid and not with windmills.

          • OpenSourceElectricity says:

            @ Kees – problem is that you do niot understand that the inverters can do the same thing just
            – faster
            – with more energy.
            They do not have to wait till a speed difference between field and iron has created a certain angle difference which results in a power output. And they are not restricted to use just a tiny speed difference, they can extract much more energy from the rotation.
            What is neccesary to understand that the problem is not in the wind power station, the problem is in the grid code.
            And in case of El Hierro in the way the system is operated. And to some degree in the way the system is built.
            So far I have seen several ways how the system could have been built much more useful without making it much more expensive.

          • Kees van der Pool says:

            Open, you wrote: “@ Kees – problem is that you do niot understand that the inverters can do the same thing just
            – faster
            – with more energy.
            They do not have to wait till a speed difference between field and iron has created a certain angle difference which results in a power output. And they are not restricted to use just a tiny speed difference, they can extract much more energy from the rotation”

            You are 100% correct, I don’t understand any of this. Waiting for a “certain angle difference”? You just destabilized every single power grid in the world. Total nonsense.

            As far as El Hierro is concerned, they don’t have a frequency stability problem – that was put to rest years ago when the system was designed. In addition to the diesels, up to four big hydro generators are spinning at the required line frequency that can instantly generate 50MW+ at exactly that line frequency, far beyond what is needed for any conceivable disturbance.

            You seriously need to read more, here are some fine writeups:

            “Power System Stability of a Small Sized Isolated Network Supplied by a Combined Wind-Pumped Storage Generation System: A Case Study in the Canary Islands”


    • Kees van der Pool says:

      Rainer, REE considers demand = grid + pumping.

      • Total generation at GdV = diesel + wind + hydro, with the hydro often negative to signify net uphill pumping.

        REE’s demand numbers are typically 0.1 to 0.2MW less than total generation but I don’t know why. Maybe they allow for line losses?

      • Rainer says:

        Sorry Kees,
        REE prints here:
        Seguimiento de la demanda de energía eléctrica (MW)
        Real and Prevista.

        Also en
        REE prints Real

        The “Real” in my example is exactly the demand
        So for me the % base on production and not on demand.
        Where the production=wind+diesel+(-hydro)

        Or just do not make any sense at all……

        • Kees van der Pool says:

          Rainer, I know what its says. Whatever your interpretation of ‘demanda’ is, the following equation has to be satisfied otherwise things go seriously wrong:

          power generated=power used
          diesel+hydro+wind=grid demand+pumping

          Plug in the numbers and it all makes sense, give or take a few 100kW (transmission losses, voltage variations and such).

          • Rainer says:

            Hola Kees.
            “power generated=power used
            diesel+hydro+wind=grid demand+pumping”

            “otherwise things go seriously wrong”
            that is it!

            REE use “Demanda Real” exactly like i understand demand: That is what is used by the clients.
            All other energy generated or pumped is just intern of the plant and in my understanding no demand of a client.

            Like you showed very clear: power generated is really not demand!

            The solution of my first look i think is:
            The % in the graphics are the % of power generated and not the % of demand.

          • Kees van der Pool says:

            Hi Rainer,

            Pumping is just as much a client as the grid itself – it is part of the energy bookkeeping. Most of it gets wasted but there is also a fraction that shows up on the ‘generating’ side of the equation in the form of ‘hydro’.

            One month to go?


  13. Stuart Brown says:

    Folks – have you looked up El Hierro on wikipedia?

    ‘This hydro- and wind-power project, created by the local Gorona del Viento El Hierro consortium with financial aid from the European Union, and officially inaugurated in 2015, consists of five wind turbines of type E-70 capable of producing 11.5 megawatts of wind power to supply electricity for approximately 11,000 residents, an additional number of tourists, and three water desalination facilities. The hybrid wind/pumped hydro storage system stores surplus wind power by pumping water up 700 meters (approximately 2,300 feet) to fill the crater of an extinct volcano. When winds are calm or when demand exceeds supply, water is released from the crater to generate 11.3 MW of electricity, filling an artificial basin created at the bottom of the extinct volcano. Water in the lower basin is then pumped back up again to the upper reservoir when there is excess wind power.[27]

    The closed-loop hybrid wind/hydro system is expected to save approximately US$4M per year (calculated with January 2011 oil prices) previously spent on about 40,000 barrels of crude oil imported annually, and makes the island completely self-sufficient for electrical energy.’

    … and a picture of a wind turbine captioned
    ‘Assembly of the first of five wind turbines with 2.5 MW each, which are the island’s only electricity supply.’

  14. Rainer says:

    @Kees, Open,
    Interesting discussion about inertia, frequency etc.
    Think both of you did demonstrate me a lot of background knowledge.

    Still learning that stuff.
    Hopefully the “GDV tecnicos” also are learning.

  15. Roger Andrews says:


    Allow me to put some ground truth into your extended discussions about the merits or demerits of wind turbines.

    A rough count shows that there have been 178 high-wind days since project startup. GdV operated with the diesel plant providing baseload generation (usually ~1.6 or ~3.2MW) and wind generation making up the difference for 156 of these days, but operated with 100% wind generation for only the remaining 22. There is no obvious difference in wind conditions between the 22 days when wind supplied 100% of GdV’s generation and the 156 days when it didn’t, and 100% wind generation is the desired result. We can therefore confidently conclude that, for whatever reason, wind acts to destabilize the El Hierro grid.

    • Kees van der Pool says:

      Hi Roger,

      If I understand your argument correctly, instability is defined as “the wind is not doing what it is supposed to do, all things being the same”.

      I feel there are too many variables (wind@altitude, reservoir levels, weather forecast and the degree to which GdV/Enercon wishes to take risks) to christen the whole operation chronically “destabilized”.

      Certainly “unsatisfactory” but 22 days of 100% RE show the basic regulation algorithms work fine.


      • Roger Andrews says:


        My argument is simply that until we get more data all our attempts to identify the cause(s) of grid instability are speculation. However, I would change my mind if you could tell me exactly why the just-completed 100% renewables test started and ended when it did. 🙂 The REE grid data are accessible through the sidebar and the wind data are at http://rp5.ua/Weather_archive_in_El_Hierro_%28airport%29 if you want to look at them.

        • Kees van der Pool says:

          Roger, my SWAG is that the wind was steady when they ramped down the diesels and transferred the control to the Peltons. The single diesels went flat (no regulation) before they were shutdown. At that time, balancing and frequency control was the responsibility of the pumps and Peltons respectively, wthe the Peltons in ‘wet’ mode. Lots of pumping to keep sufficient water in the UR.

          The wind has become clearly more erratic with more hydro needed so a single diesel was added @ 9:50, still in ‘non regulating’ mode. The forecast for Monday, wind-wise, is not that great either. No need to invoke ‘instability’.


          But again, thats just my guess. . . . .

          • Kees van der Pool says:


            According to the evaporation rate of Dr. Flocard’s paper, they must be running from day to day, if not from hour to hour with respect to the water levels. This, of course, if no water was added.

            Earlier this year, a blackout was caused by the hydro ‘not showing up’ , most likely because a low water levels in the UR. An inquiry was promised by GdV as to the reason (s). I don’t think they will take that risk again, especially with Podemos pushing for openness.

            I hope Rainer can take some more of his mighty pictures that allow your photogrammetric skills to determine how/if the levels are different from last year.


    • Rainer says:

      I am also not satisfied with GDV’s results so far. It is also indisputable that irregular energy such as wind is difficult to handle.
      However, the purpose of GDV is to show a way to integrate wind energy on a large scale into an island network. As Kees has shown, this has so far been successful on 22 days and is currently being held at the time since 3:20.
      Furthermore, I have the expectation that the technology is further developed and we will not stand still on the knowledge of James Watt. The “modern” technique, such as nuclear plants, propagated from other sides are still based on the principles of the first steam engine, which are now physically very narrow in the efficiency range. The long-term effects are also not solved. We will have to develop further. However, we should not let the realities out of our own eyes.
      Your Blog here is the best example to look closely to the facts.

  16. Rainer says:

    2016-11-12 03:20 diesel off 100% RE in action

  17. Rainer says:

    Maybe new data of GDV will come till end of this month:

    Google translator
    “The Commissioner of Transparency resolves in favor of Podemos and asks the Cabildo of El Hierro to give information about Gorona”
    “To this end, the Commissioner has requested the Cabildo Insular to send the documentation requested by the Director within 15 business days.”

  18. Rainer says:

    2016-11-13 09:50 diesel on again.
    Why? Again another secret of GDV….
    My calculation: 548h RE only, still far under 5%.

  19. Rainer says:

    As an islander GDV judges:
    Unfortunately, he still denies reality.
    It is worth to translate more of it part by part than this example:

    Google translator
    “Saving energy for when we need it is a simple idea. The same as our grandparents always did; The same that the tango dancers have always done. An idea that seemed impossible but now, for a year, is a clean and harmonious reality like the very Tango Herreño.”


    • Roger Andrews says:

      Thanks for the link Rainer. The author is clearly living in a world of his own. I particularly liked this bit:

      El Hierro demuestra que las energías renovables son una solución energética viable para millones de personas en el mundo. (El Hierro demonstrates that renewable energy is a viable energy solution for millions of people in the world.)

      He spells Hubert Flocard’s name wrong too.

      I was going to leave a comment but see that you’ve already done it for me.

      Are you on El Hierro now?

      • Rainer says:

        Next Week.
        By the way:
        As far i know the author is the man behind the Idea of GDV.
        He have all my respect
        The idea is a fine one.
        But is is hard to see what came out of the really fine idea…..
        And after dreaming sometimes we have to look at the really facts.

  20. Rainer says:

    New pictures:
    Field-studies-2016-12-08.txt ca 17:00 – ca 17:30
    All pictures now also with seconds in the name


    Field-studies-2016-12-03.txt ca 13:20 – ca 15:00
    All pictures now also with seconds in the name


    lower storage:
    storage relativ full…. Roger please verify with your metering

    water coming in
    Peltons working
    Pumps NOT working

    still not clear if the meter belongs to GDV ….
    meter not running
    627 qm since 2016-04-13

    Upper storage:
    New situation:
    Truck with debit / cleaning of storage??
    3 new metering posts near outlet / inlet
    storage nearly empty…. outlet visible /
    Roger please verify with your metering

    water meter running fast/ plastic tube shaking / also air coming in ??
    right now: 112 qm per hour
    76036 qm since 2016-04-13

    lower storage:
    storage relativ full…. Roger please verify with your metering
    no really change since 2016-12-03

    Observations -ca 17:25:
    NO water coming in
    Peltons NOT working
    Pumps working

    still not clear if the meter belongs to GDV ….
    meter not running
    2 qm since 2016-12-03

    Upper storage:
    storage nearly empty…. outlet visible but under waterlevel/
    Roger please verify with your metering

    water meter running fast/ plastic tube shaking / also air coming in ??
    11738 qm since 2016-12-03
    means 11735qm/193,3h = 60qm/h

    second water input found
    the meter of the new input not found
    But water running in storage is visible

    Also made some pictures of the tube to the new found water input

    • Rainer: My computer finally decided you weren’t trying to steal all my money and will now let me look at your pictures :-). They show some very interesting results – particularly this one, which shows a lot of wrinkles in the upper reservoir liner. Anyone with experience of liner defects is encouraged to provide an interpretation:

  21. Joneuga says:

    Hi Roger,

    I am doing a proyect about GDV central and need some data about the wind as the direction and the speed. Also I can not understood why there are only 5 generators of eolic. Could you tell me where can I find this information?

    Thanks you for all the information you give in this web, It is very helpfull.

Comments are closed.