back to article Big EU imports of Sahara sun-power coming soon?

The European Union might subsidise "interconnector" undersea power lines beneath the Mediterranean for the purpose of importing solar energy from the Sahara desert, according to reports. "I think some models starting in the next 5 years will bring some hundreds of megawatts to the European market," European Energy Commissioner …

COMMENTS

This topic is closed for new posts.
  1. Anonymous Coward
    WTF?

    why not just install solar panels in europe?

    this just boggles my mind, why go to the effort and expense (along with the associated environmental impact) when we should encourage users to put panels on their own roofs and commercial buildings?

    must be devised by a consultant, who gets a great kickback . . . this just seems too usual these days.

    burn them, burn them all!

    1. Charlie Clark Silver badge

      Efficiency

      Germany is already heavily subsidising roof-top solar panels. However, the yield in Europe, especially North of "the line" - the Main in Germany and Loire in France - so that the subsidy is not really cost effective. Indeed the projected costs at the current rate of 32 cents per KW/h are projected to double the electricity price in Germany (article in Handelsblatt yesterday http://www.handelsblatt.com/technologie/energie_technik/solarboom-treibt-kosten-sonnenenergie-wird-unbezahlbar;2604469 )

      The basic ideas behind Desertec seem reasonable but what's missing from Lewis' article is that the project is currently just a feasibility study. A high-voltage DC network across Europe would certainly help provide power more efficiently for everyone and should help wean countries such as Spain off dirty and inefficient energy production.

    2. jonathanb Silver badge

      why not just install solar panels in europe?

      The article does answer that question. You get more kW of electricity per panel by putting it in the Sahara than you do by putting it in Scotland because you get more sunshine in the Sahara.

    3. David Simpson 1
      FAIL

      With who's £$ ?

      Maybe you can also find someone to pay for them, most solar panels barely pay back their cost over their operational lifetime which is why you want them at the equator.

      Find us a cheap solar panel and we can all tile our roofs with them.

  2. Anonymous Coward
    Anonymous Coward

    Would it be photovoltaic?

    Since most of the large solar schemes tried out in California and Spain have been solar-thermal plants which have higher efficiencies and can generate power at night by storing heat in molten salt.

  3. Richard 81

    So...

    So, because the solar power that might feasibly be captured in the Sahara isn't enough to supply world's demands on its own, the whole idea is bunk?

    If your numbers are correct, then clearly the statement that "If just 1 per cent of the Sahara Desert were covered in concentrating solar panels it would create enough energy to power the entire world. That's a powerful number ..." is a gross exaggeration. I accept that.

    It still sounds like a good idea though. If nothing else, Africa always needs more infrastructure.

    1. Steve Crook

      Yes, but what infrastructure?

      Africa got infrastructure when it was colonized. But it was infrastructure that suited the colonizers. So lots of roads and railways to the coast, but bugger all connecting the internal parts of the continent. While I admire your optimism, I can't help feeling that any infrastructure generated would be what was required to build and run the collector network.

      Fact is, stuff lives in the Sahara (people included), and building several square kilometres of solar collectors (of any sort) is going to help their ecosystem not one bit.

      Lets just get on with it and build the nuclear reactors now...

      1. crowley

        help their ecosystem?

        "building several square kilometres of solar collectors (of any sort) is going to help their ecosystem not one bit."

        I've read that the shadow from the mirrors of such infrastructure would create micro-climates where air vapour could be encouraged to condense and feed crops underneath.

    2. Yannick

      Stable governments

      You'd also need stable, uncorrupted governments to "partner" with. Personally that is my main concern, technical issues can be solved, political ones on the other hand.......

      1. Red Bren
        Coat

        Stable, uncorrupted government

        As soon as we elect one, we should let the Africans know...

    3. Chad H.
      Stop

      Indeed

      Indeed Naysaying is fun, but where's vulture central's better idea? Could we put wind generators on vultures? What about Swallows? Could it possibly work if we get 2 swallows (or vultures) and have them carry it on a bit of sting between them?

      1. Steve Crook

        Nukes.

        There's no actual suggestion that what is proposed will work. There is no idea of the consequences of building something of this scale in the Sahara (assuming it can be built). Just because there's a lot of 'useless' sand, doesn't mean that there's not something using it, or living in it, or something that depends on it being heated by the sun.

        This isn't a panacea, and building it will have consequences. Plainly you know what they are. I don't, and I suspect that so far the research hasn't been done. I'm just being pragmatic. You're being (IMO) overly optimistic. Personally, I think history bears out my POV.

      2. You're all dinosaurs
        Troll

        The power of negativity

        Shhh...Vulture Central is secretly planning a new power plant which feeds on the schadenfreude, negativity and smugness of people who sit at their desks all day saying "that'll never work" while doing bugger all themselves

  4. Anonymous Coward
    Stop

    This helps the UK how?

    I'm kinda thinking that this wont help the UK at all, indeed it realy only helps those countries closest to the source and the UK is pretty darn far from it. Indeed if those countries that benifit from this then go oh we dont need so many power stations they in themselfs will generate less power and as such have less to export and also import less from elsewere. Bottom line this not only dosn;t help the UK but actualy will make our electricity more expensive in the long-run.

    So EU subsidising this then they can pay for it in deutch marks thank you very much, no pounds going on this one. the transmission distance alone would make it unviable in every possible way to be of any use to the UK - seriously.

    Now if they were to work with the Icelandic goverment and cut a deal to tap some of there lovely thermal vents for power I'm sure we in the UK could benifit more than the rest of EU as a whole and would also allow Iceland to appease the bank greedy, dont read teh small print loss makers. That would be more productive from a UK perspective. Eu going to do that, yeah right as it dont help zee germans.

    ANON just incase I wish to invade europe at a later stage in my life :D.

    1. Anonymous Coward
      Anonymous Coward

      Iceland

      There've been a number of studies that have all come to the conclusion that up to 1GWe could be brought to the UK via a high voltage DC cable strung from Iceland to Scotland for less than the cost of a nuclear power station. The Icelanders would probably be happy as it would allow them to sell power at a commercial rate rather than the heavily subsidised rates used by aluminium and ferrosilicon plants.

      Though there is growing concern in Iceland at the environmental effects of large-scale hydro power (which supplies about 75% of their output). At the moment they have a power surplus (which must be nice), but there are extremely controversial plans to put more dams on the epic Þjórsá near Hekla. What they'll do with this power is uncertain, aluminium smelting is deeply unpopular as it doesn't require much skilled labour and all the value is added when the metal leaves Iceland. So there is a big push to get server farms to come to Iceland - there's a huge one at Keflavík and even the prospect of solar silicon manufacture.

      But why risk those when there's a big island to the South that's having trouble keeping the lights on?

      1. Eastander
        Headmaster

        Iceland - better with Geothermal Energy

        Surprised Iceland use Hydroelectricity so much. Guess it's cheap(er), but I'd presume they also have huge potential for Geothermal energy which perhaps could also be cheaper than a Nuke power station

    2. Anonymous Coward
      Grenade

      1945 / 1966 and all that?

      Hi the Daily Mail are calling, they want you to write a column.

      "So EU subsidising this then they can pay for it in deutch marks thank you "

      Err Germany use the Euro.

      That would be more productive from a UK perspective. Eu going to do that, yeah right as it dont help zee germans.........

      Ok here is a link

      http://maps.google.co.uk/maps?hl=en&q=map+of+europe&um=1&ie=UTF-8&hq=&hnear=Europe&gl=uk&ei=2NchTISrBcK4jAea26yuAQ&sa=X&oi=geocode_result&ct=image&resnum=1&ved=0CB0Q8gEwAA

      Notice how germany is pretty much level with the UK and therefore just as unlikely to receive this electric as we are. Maybe if you had a bash at the Italians, French or Spanish, you may have been more on the ball.

      Anyway. I' m off to evict a bloody foreign gypo alysum seeker from my wheelie bin, I don't want to pay for the extra weight, what with all the lightbulbs I have to throw out waht with the eu rules on mobile phone masts and all that.

  5. David Pollard

    Jaundiced?

    Though it's clear that PV alone doesn't offer a silver bullet solution to the forthcoming energy shortage, estimates of 6.8% for efficiency and 50% of available area for access seem a bit on the mean side. David Mackay gives useful - and probably reliable - estimates here: http://www.inference.phy.cam.ac.uk/withouthotair/c6/page_38.shtml

    As with wind energy, the problem with solar is not so much in generating electricity or transporting it, it's in storing it.

    1. copsewood

      storing it using hydro

      We'd be a lot less worried about electricity storage if the world's hydro dams had been designed to generate fluctuating output when it isn't coming from the sun or wind as opposed to constant output,e.g. for feeding aluminium smelters or baseload. Allowing the water to rise and fall behind the dam by uprating the turbines on existing dams is going to get this kind of attention, as with continental size DC grids, because the places with the best hydro resources are often a couple of thousand kilometers away from the places with good wind or solar potential. As it is, the investment needed to uprate existing dams is much less than building them in the first place.

  6. Anonymous Coward
    Megaphone

    has any one cosider the effect of such a large scale energy farming on global climate/ weather

    NOT too fast there may be serious danger to such large scale energy farming on global climate/ weather

    1. Ken Hagan Gold badge
      Happy

      Re: effects on climate

      Almost anything you do over a surface area as large as the Sahara might have an effect on global climate, simply by changing Earth's albedo. Rather than putting dark things like solar panels there, perhaps we should put shiny things like mirrors instead, and then get on with burning fossil fuels as usual.

  7. Mike 140
    FAIL

    more greenwash

    For a proper analysis of this hype, just read here

    http://depletedcranium.com/the-realities-of-sahara-solar-power/

  8. John Smith 19 Gold badge
    Flame

    6.8% my extrordinarily large backside. V. Poor journalism.

    As El Reg knows full well the people pushing this proposal are looking at a solar *thermal* system using trough reflectors heating glass tubes carrying some kind of oil* to drive what is basically a steam turbine power station. Given that Schott glass is one of the major contributors to the design this should not come as much of a surprise.

    Modern steam generated power plants can hit 33%. In principle this could be generated at DC and sent directly down a DC line to Europe followed by a DC-AC conversion but I'll assume its a AC-DC then DC-AC link with 95% efficiency (IIRC this process has been done at 98% both ways)

    So 976 (actual solar constant, not that it's particularly constant) *33%*95%*95%*0.5 (for that 1/2 the full power output)

    I make that 14.8% *average* efficiency per year.. Powered by the sun for the next several million years.

    Very poor research. That 6.8% is a 1st generation lab system. *ALL* PV systems only *efficiently* absorb energy around the band gap. the rest is lost as heat. Solar thermal absorbs as a *black* body, at *all* parts of the spectrum.

    (I'd still like to see Gallium, which would remain liquid up to 2000c, as sadly would most reasonable containers).

    1. DaWolf

      aye

      nothing wrong with the article, until you get to the bootnote. Whish is a pile of pish.

  9. E 2
    Thumb Up

    6 percent?

    Lewis:

    Surely the combined area of all the large cities amounts to something on the order of 6% of the planet's surface? Solar power generation would I think involve less infrastructure per square meter than does a city. Paving the Sahara in solar generation systems is not so much a question of wealth required as of political will.

    I say, do it.

  10. Anonymous Coward
    Anonymous Coward

    "stable, uncorrupted governments to "partner" with. "

    Like the one we have here in the UK, definitely no corruption. No questionable wars, no expense fiddling by public officials, no shady deals with Murdoch or other big foreign donors, and BAe are as pure as the driven snow, they've never ever declared anything airworthy that wasn't (see below, or just ask Tony Blair).

    Anyway, marginally more seriously: think about where our oil and our (liquefied) natural gas come from these days. Are the governments in that picture known for their stability and freedom from corruption? Iraq, Libya, Nigeria (to name but three)?

    Wrt Mackay: he's usually excellent but quoting PV efficiency here may be unfortunate, there's some good work going on at the moment using rocks for large scale high efficiency high temperature-difference heat storage, which would knock spots off PV efficiencies as well as solving some of the storage problem. Sorry, no links (just can't remember, but others might) but it sounds a lot more plausible than BloomBolloxes (tm).

    "the transmission distance alone would make it unviable in every possible way to be of any use to the UK - seriously."

    Says who? Based on what? Proven HVDC transmission technologies (e.g. what we already use for a 1GW or so interconnector with France) would mean that the energy lost in transmission would be relatively small.

    "Lets just get on with it and build the nuclear reactors now..."

    Too late. There aren't many companies anywhere qualified to do it and "the market" in the UK (which runs, or maybe ruins, our non-existent strategic energy planning) has ensured we're at the back of the worldwide queue for nukes. We need something which doesn't have a colossal queue which can't be queue-jumped, something relatively proven and quick.

    "... Iceland ..."

    They do owe us loadsamoney, and energy is one way they could pay (fish any good to you?). But it's relatively small scale, and a lot of the power cables would be undersea. There's some recent evidence that undersea technology isn't always quite as reliable as you might hope. Fortunately the Med's relatively calm and peaceful.

    Anyway, if Lewis is short of things to write about, we're still waiting for his coverage of last year's Nimrod inquiry report:

    http://www.guardian.co.uk/commentisfree/2009/oct/29/nimrod-crash-inquiry-raf-afghanistan

  11. Anonymous Coward
    Anonymous Coward

    This won't reduce the need for power stations in Europe

    This won't reduce the need for power stations in Europe. Peak demand is achieved in the winter months, at around 6pm. The sun sets on the westernmost tip of Africa at 1730 GMT in midwinter. You're not going to be getting anywhere near full power out of the panels at that point, making them relatively useless in meeting peak demand.

    The net effect of this would be to maintain the requirement for fossil plant to meet peak demand, but to reduce time period at which it's profitable to run fossil plant, meaning their operators have a lower period of time in which to recoup their capex and opex. This will have a downward pressure on power prices over the middle of the day, and upward pressure over the evening. Given spot power prices are generally highest in an evening, this is puts us in an unhappy place.

    Of course, we could pump water to the top of a hill over the day, and let it run down again in the evening to store energy a la Dinorwig, but that requires even more capital investment...

  12. Anonymous Coward
    Anonymous Coward

    CSP conversion efficiency 6.8%?

    I thought the CSP conversion efficiency holy grail was to get from around 30% to > 40%?

  13. Martin Audley
    FAIL

    You did read the figure, right? €400 BILLION

    Not million. *BILLION*. *400 BILLION EUROS*. 400 * 10^9 EUROS. That one project would be equivalent to 2.7% of the total EU GDP.

    For a power system which will provide no power to Europe in the winter at night.

    The project's target is to provide 20% of EU power. And all that power needing to be backed up by the same power output of standby gas turbines for whenever the sun doesn't put his hat on.

    It would provide a small proportion of the EU electricity consumptions of 342gigawatts.

    "It might scale up to the gigawatt range" Yeah right. Even if it produced 10 gigawatts that's still 40,000 Euro/kW. When a nuclear power station costs around $10,000/kW worst case, and down to $1,000/kW.

    Good luck with that. If you're still interested, I've got a bridge you like to buy...

    1. DaWolf

      it wouldn't be solar panels

      But Concentrated Solar Power, a form of Solar Thermal. Solar thermal heats liquids to very high temperatures and uses them to drive turbines. It's already been proved in some Spanish solar thermal plants that you can use this hot liquid as an energy storage, then get the energy back at some later time.

      As for winter - the differences between summer and winter get less as you get closer to the equator. And we use less power in the winter at night than in the winter during the day.

      I love the way you make up numbers both on how many gigawatts it would build, then others on how much nuclear costs. Both are completely wrong btw.

  14. Richard Foersom
    Go

    CSP with heat storage

    As noted by John Smith 19, the Desertec systems will most likely be CSP - using large mirror arrays. This scales well and can reuse lots of tech from conventional stream cycle power plants (coal/gas/nuclear). CSP has the added benefit that you can integrate a "heat-battery" with molten salt so you can generate power after sun-down. Look up Andasol and PS20 for more info.

  15. Rogerborg

    Yes, it's solar thermal, not photovoltaic

    When you're cribbing from Slashdot - SLASHDOT! - then really, it's time to admit to yourself that you know nothing about the subject, and try to avoid making it too obvious.

  16. John Smith 19 Gold badge
    Coat

    @Richard Foersom

    "CSP has the added benefit that you can integrate a "heat-battery" with molten salt so you can generate power after sun-down. Look up Andasol and PS20 for more info."

    Quite so. IIRC the storage CSP plants have used Sodium Nitrate (Ammonium Nitrate could be used and might be cheaper but with the addition of some fuel oil would convert it into the mother of all fertilizer bombs. Not good in Algeria which has been have a few problems with fundamentalist whack jobs of late).

    A landmark study for all this was done by the US Navy's ONR in the late 70's-early 80's. Their "Solchem" project was designed to make the US Navy self sufficient in oil but only using US sourced raw materials. They planed to use solar thermal heating of receivers made of clay to drive the Haber Ammonia reaction and store the energy as warm piped high pressure ammonia which could then be run over a splitter catalyst to release the heat into spray cans full of more-or-less table salt (eutectic sodium/potassium chloride mix at c500c). High temperature (but only in the heat store and receiver. Most of the high pressure piping is fairly cool) on demand for steam raising or chemical processing (Fisher-Topsch, synthesis from Methane upward?)When you're planning to build infrastructure to replace the oil needs of the US Navy, large scale economics matter a hell of a lot. They were thinking in terms of "Quads" equivalent.

    Reagan got elected, proclaimed the era of cheap oil, shut down most of the DoE programmes (who were pat funding it) and the ORL went back to weapons research and SDI.

    I think Australia has continued work on the concept.

    You can guess what reports in my pocket.

  17. Anonymous Coward
    Grenade

    More of the same?

    Sounds like the EU is getting more specific about "administering" (i.e. non-military invasion by bureaucracy) some north African countries.

    First they started with building grain mountains at more cost than using it for aid.

    Then they kept pumping money into economies that needed to be reformed instead of subsidised to keep growing in their current direction, until they became fully-fledged vampires (see, I didn't call them PIIGS!)

    Then they bulldozed democracy to install a self-amending treaty (that quietly allows the re-introduction of the death penalty for rioting, the Met and the CRS will love that).

    Next they failed totally to bring about economic stability.

    Now they're looking for somewhere else to screw over.

  18. Jacob Lipman
    Welcome

    What else?

    Cost of transmission... What is that usually, about 50% loss in transmission?

    So long as you magically produce an inexpensive ambient-temperature superconductor, increase the efficiency of solar cells to 186%, cure cancer (just for good measure) and rewrite the laws of thermodynamics, 1% of the Sahara should be more than sufficient.

    We hire our legislators to write laws, yes? Why have we allowed physicists to get away with it for so long?

    I, for one, welcome our new desert-dwelling, superconducting, physics-defying, green-powered North-Africa-exploiting Eurocentric overlords.

    1. John Smith 19 Gold badge
      Happy

      @Jacob Lipman

      Well my 2 minute of Google says HV DC has a 25% transmission loss but it's the cheapest way as it needs 2 conductors rather than than the 4 or 6 people need for AC. If *any* part of route goes through sea water that makes the AC cable a *lot* less efficient (the water acts like a giant capacitor that is being charged and discharged)

      So no, 1 way loses at most 25% (which should drop with ever improving power electronics and better cooling of the devices). Including the line loss knocks the overall efficiency down to 11.6% by my calculations. Note however that their is *no* raw material cost as with coal, oil or *any* combustion source.

      The Sahara is a very great deal of not very much. Not unlike the N'gev, Mojave or Nevada deserts. You'd need to take up a *lot* of most of them before anyone really cared. Power generation and its export (at a fair price) would be quite a reasonable use for them.

      I cannot understand the point of the rest of your comments.

  19. Nick Carter
    Thumb Up

    UK Energy Imports

    The naysayers dismiss any renewable energy initiative because it won't be able to provide 100% of the UK's energy requirements, as if we're currently self-sufficient in indigenous fossil fuel/uranium reserves. Maybe there was a time when we had enough North sea oil & gas and working coal mines but that isn't the case now. They're confusing electricity generating capacity self-sufficiency with energy self-sufficiency.

    I see nothing wrong with importing a substantial part of our energy requirements in the form of electricity from CSP in the Sahara instead of importing it in the form of fossil fuels and uranium.

    As for storage, if a barrage was built across the Strait of Gibraltar and the Mediterranean allowed to drop about 6 metres by evaporation (The Med would dry up in about 1000 years, about a metre per year, if it wasn't constantly replenished from the Atlantic), then the Med could be used as a massive pumped storage reservoir and Solar-Hydro generating system.

    Most parts of the world have deserts which could be utilised for CSP, maybe South Africa's electricity shortages could be solved by installing CSP in the Kalahari and Namib deserts?

    1. Chemist

      Re : "a barrage was built across the Strait of Gibraltar "

      You do realise that the straits are anything upto 900 metres deep at the narrows. That's a seriously grand civil engineering project ! Even with a longer barrage it's still ~300 metres

      1. Nick Carter
        Coat

        Re: Barrage

        Yes, I do realise how deep the strait is - there was a particularly gripping episode of 'Das Boot' that illustrated that point. It wouldn't be the first seriously grand civil engineering dam project to be built or proposed e.g. Three Gorges Dam (2,335 metres long, 185 metres High) or the Severn Barrage.

        There would probably be many other objections on aesthetic grounds to the Med being dropped by a few metres, like Ibiza and Formentera becoming one island or Venice no longer enjoying its watery views.

        Maybe the Adriatic could be reclaimed to relocate populations displaced by rising sea levels?

  20. Pascal Monett Silver badge

    Just one problem there

    I remember reading and hearing (on TV) of numerous revolts, massacres, bands of mercenaries, etc that seem to be rather active and not totally uncommon 'round those parts.

    I would hardly be surprised if some of them found it a great sport to o and blow up such expensive, high-tech installations, if only to recover some materials to sell on the black market to cover their operational expenses (you know, bullets, explosives, food and the rest).

    Which means that there is every chance that these "partnership" installations will become military installations in short order, and I don't suppose European governments are going to be content with local military, seeing as it can, often as not, be bribed to look the other way.

    Consequently, it'll be UN, or NATO at least, that will be protecting these installations. And given that UN does not have the right to shoot, we'll probably wind up with good ol' Euro-country troops or, if worst comes to worst, US soldiers to do the "protecting".

    This is starting to sound like colonization all over again.

    1. Nick Carter

      Protecting Installations

      I suspect that the countries where the CSP installations will be built in the Sahara, like Algeria & Libya will be very keen to protect these facilities themselves to maintain a valuable source of income to replace dwindling oil revenues now that the world has passed peak oil. Unlike oil there is nothing to gain by holding back production in an attempt to manipulate the price because solar power can't be easily stored in situ so would be wasted if it isn't exported as it is being generated.

      If CSP is spread over many North African states then it will be less easy for one state to corner the market or operate a cartel.

  21. Michael Wojcik Silver badge

    Why transport it as electricity?

    Out of curiosity, if you had a big solar-thermal plant in the Sahara, why export electricity to Europe? Why not use the power to synthesize, say, octanes from water atmospheric CO2, and ship that? European refiners could mix in a little hexane (well, in practice no doubt a cocktail of other hydrocarbons) and additives; I believe there's an existing market and distribution system for gasoline / petrol.

    No power-storage issues, because you're already storing it in a form that you're prepared to handle. No need to build a big HVDC grid, at least not right away. Let the hydrocarbon market pay for at least some of the initial investment in the Saharan solar plant, using existing transport and delivery infrastructure. Then pitch your electric-export plan, now that you have a working generation plant.

    I don't know how efficient octane synthesis is, but since the inputs are mostly free once the plant is built, it seems like it could be profitable. (Shipping in water could be expensive, so maybe it'd make more sense to run electricity from the plant up to the coast and do the synthesis there.)

    Or is this a completely stupid idea?

    1. Chemist

      Re : Why transport it as electricity?

      Sounds great

      However

      Generating hydrogen as feedstock by high temp. electrolysis has an efficiency ~50%

      Concentrating carbon dioxide from the atmosphere must be quite inefficient due to its low concentration. Of course if you have a good concentrated source that's go to be better.

      Making hydrocarbons from carbon dioxide/ hydrogen is still under active research - final efficiency ??

      Burning the hydrocarbons to generate electricity ~~35% efficiency.

      So currently the overall energy efficiency ( <<17%) looks very poor which is presumably why nobody is rushing to use this to store renewables generated during off-peak times.

    2. John Smith 19 Gold badge
      Boffin

      Some other solar chemical alternatives

      One of the other paths the Solchem project looked at was making "Producer gas," which is a mix of Methane and Hydrogen from passing water and CO2 over a (solar) heated catalyst.

      The U of New Mexico got a pilot plant working before the project was shut down.

      Slightly more recently (and somewhat more radical) was a 1994 US project in solar thermoelectrochemical conversion. This split a salt (unspecified which) back into a base + acid then recombine them in a fuel cell in a continuous loop. the unclassified summary indicates Hughes were getting something like 30-40-%. Note this is *direct* heat to electricity. Depending on volume the 2 reactants either allow carriage of electricity without needing large chunks of Aluminium or Copper, or *indefinite* stored electricity in large tanks. Note such a system has (in principle) the quick starting of a turbine power station while maintaining efficiency. Unfortunately the full report still seems to be under a secrecy order for some reason.

      Further details at http://www.osti.gov/energycitations/

      Which makes a fascinating burrow through the DoE archives.

      1. Chemist

        Re : Some other solar chemical alternatives

        I'm sorry you can't get methane + hydrogen from water + CO2

        I think you'll find the Solchem project reaction (was supposed to be ) CH4(methane) + CO2 -> H2 + CO + H2O. I say supposed to be because the stoichiometry is wrong in the only published explanation I can find. I'd make it CO2 +CH4 -> 2CO + 2H2

        I've just found a pdf sponsored by the US DoE that confirms CO2 +CH4 -> 2CO + 2H2

        http://www.osti.gov/bridge/servlets/purl/10131314-JCwtG8/native/10131314.pdf

        So basically it needs methane as a feedstock

        1. Nick Carter
          Pint

          Hydrogenation

          What would be chemical feasability of adding Hydrogen (from electrolysis) to coal to give methane which can then be exported by the usual methods (I think Algeria exports natural gas now). Obviously the coal would have to be brought in from somewhere else and this would still involve CO2 emissions, but at least some of the energy content would be from renewables. Or the world's supply of ammonia based fertilizers could be manufactured close to the CSP plants (and why not relocate all energy intensive but low labour industries to where the solar plants are (See Mike Richards comment above about Aluminium smelters).

          1. Chemist

            Re : Hydrogenation

            Chemically it's certainly possible to generate a range of fuels from a carbon source + hydrogen. The efficiency is pretty poor and involves CO2 emissions. Hydrogen being used in fuel cells is a more efficient process AFAIK but would involve massive production of the cells.

        2. John Smith 19 Gold badge
          Happy

          @Chemist

          Which goes to show what happens when you type without checking facts (if I keep that up I might have a career in journalism).

          You should keep in mind that its prime goal was *not* direct solar heated chemistry but moving the heat in a closed *loop* to a molten salt storage system, *without* the heat losses from a normal hot fluid. Hence the interest in pairs of endothermic/exothermic reactions at each end, culminating in the Hughes thermal cracking of salt to fuel cell feedstock idea.

          BTW Thanks for the ref. It's nothing like the only one I've seen on the project and a nice reminder that ECD is a treasure house of stuff. Some of their collection dates back to the Manhattan project, if you can find it.

      2. This post has been deleted by its author

  22. Anonymous Coward
    Pint

    Re: Why transport it as electricity.

    Why indeed, but perhaps the details could be improved (eg the chemistry, as already noted :)).

    Take the electricity cables to the coast, perhaps to ports that already have liquefied natural gas (LNG) export facilities (or build some new faciltiies, if there aren't already any convenient ones - they're a lot quicker to build than (say) a set of UK nuclear power stations that isn't anywhere near being ordered yet).

    At the coast, use electricity and seawater to create hydrogen, liquefy it as per existing LNG technology from North Africa, ship it to the UK (European?) ports that already have LNG import technology (or again build some if not convenient) and ship it onward to large gas consumers such as gas-powered electricity generating stations which can readily be adapted to burn H2 as well as/instead of CH4.

    Obviously the overall efficiency is far from ideal, but it helps contribute to an ongoing supply of electricity in Europe (and in particular in the UK, where privatisation has left us with no energy supply strategy). And it gets around the daily "no sun at night" problem AND around the "enough storage for a week or two" issue, and most of the technology is tried tested and proven, it's just that the madness of the market combined with "the tragedy of the commons" has meant there's been no incentive to address the issue.

    Incidentally, I think some of the HVDC transmission loss figures quoted above (the 25%-50% ones) are ridiculous until proven otherwise (definitive sources). Desertec themselves are claiming 10-15% but they're not exactly independent. E.g. in www.desertec.org/downloads/summary_en.pdf

    So send some of it by cable at high efficiency but with no storage, and some of it as liquid hydrogen, lower efficiency but storage is inherent in the process. The energy input is "free" anyway.

    Diversity. In energy supply, a reasonable amount of diversity is A Good Thing.

    1. Nick Carter
      Thumb Up

      Desertec website

      Thanks for the above link. I think nearly all the comments/objections are covered by www.desertec.org/en/concept/faq/

    2. John Smith 19 Gold badge
      Happy

      AC@12:34

      "At the coast, use electricity and seawater to create hydrogen, liquefy it as per existing LNG technology from North Africa, ship it to the UK (European?) ports that already have LNG import technology (or again build some if not convenient) and ship it onward to large gas consumers such as gas-powered electricity generating stations which can readily be adapted to burn H2 as well as/instead of CH4"

      Just to re-cap desertec's plan is to use the sun to heat a fluid (low pressure but *very* hot) so it can be stored or used to make steam (very hot and very high pressure) to drive existing tech steam turbines. Depending how much fluid you keep in the loop you either have a fast responding system or one with substantial storage running after sun down.

      As for your idea about Hydrogen being like LNG storage you are *very* wrong. A heat leak on an LNG take will freeze water out of the air. A heat leak on a Hydrogen tank will give a pool of liquid Oxygen as it's 5 x colder than LNG. That's 111k Vs 20k. If that sounds harmless to you perhaps you should try it yourself. Hydrogen also has the ability to diffuse through most metal pipes (and it does even better with other materials) while making them prone to fracture (a process called Hydrogen embrittlement)

      Producing Hydrogen for long term *storage* or long distance *transport* is almost *never* the answer. It has been commented upon before. Yes it *is* the cleanest burning fuel possible. It's other features (and there are a lot) make it a royal PITA in *every* other way.

  23. Anonymous Coward
    Anonymous Coward

    Desertec vs nuclear

    Let's have a quick look.

    Traditional nuclear: capital intensive, running costs greatly dependent on cost of money and long term waste storage costs, limited ability to follow daily demand cycle (for economic and technical reasons). Capital costs unproven (Flamanville not so bad, Olkiluoto not so good). Huge construction leadtimes due to technical and regulatory considerations.

    Desertec-style: capital intensive, running costs greatly dependent on cost of money (but no long term storage costs), limited ability to follow daily demand cycle (cost of energy storage). Capital costs largely proven (HVDC and CSP both in use elsewhere, all this needs is to scale up, and ideally get some new storage to handly the daily cycle). Construction leadtimes probably no worse than nuclear, regulatory aspects probably simpler.

    (sometimes a table is worth a thousand words, but...)

    So, where are the big differences? If nuclear makes financial sense (and some folk think it does), there's no basic reason why Desertec doesn't too, in fact Desertec makes *more* sense because more of it is simpler.

    1. John Smith 19 Gold badge
      Happy

      AC@19:29

      I think there's a place for both in a lower carbon economy.

      From an economic point of view there are at least 2 *big* differences.

      Nuclear power stations start making electricity (or money depending on your POV) once complete. I think the French went to a *very* standardised set of designs and got this down to a fairly short period but the first build of their new design (which I think is what EDF are pitching to the UK) is still under construction. Their are some *very* big bits that can only be made by a few companies worldwide (if you go with a forged pressure vessel only 1 company has the hardware and the *certification* to do the work and *they* are Japanese. This was one of the prime elements of the planned UK govt loan to Forgemasters to buy a 15000 ton press )

      OTOH Concentrated solar can be built in stages. I'm guessing that 1st power could be 6-12 months from contract signing. You can build out from there bootstrapping off the early revenue.

      I *think* the French got it down to 18 months with their *previous* generation of reactors so not too big a difference there, but with the new generation, who knows?

      The other big one is waste. No real problem for desertec as all the materials can be recycled but a *big* one for nuclear. Not the tech, but who *pays* for it. My *impression* (and I'd love to be corrected on this) is that nuclear operators think the host *government* should pick up the bill for this. If so this is *exactly* the sort of private profit/public cost deal UK banks seem to have been enjoying. Is a business plan that *depends* on HMG picking up the tab for the disposal for all this crap "sound"? I'm no expert so I'm not sure how well *quantified* these costs are but their scale *will* be in the £Bn. That's a pretty substantial "business risk" that had better be nailed down tight.

      I have not mentioned the safety aspects which are less of a concern to financial people. However the new generation French reactor has hit trouble due to non compliant concrete and cracks in the structure (it's still under construction).

      Note that concentrate solar is *not* entirely safe. Piping round superheated steam is dangerous (contrary to films superheated steam is *invisible* and the noise can be in the ultrasonic range, giving a plume of air that will flash fry anyone walking through it). Were a section of the array to be sealed it *could* build up enough pressure to shatter the glass tubes like hand grenades and Swiss cheesing the collectors (although burst disks could stop the damage). Depending on the salt selected the heat store would be quite hazardous due to temperature and chemical nastiness to the workforce. It's difficult to conceive of a set of faults which could cause site wide damage on the scale of say 3 mile island before some fairly simple safety devices kick in and dump the problem. Not something you want to make a habit of but no permanent damage done.

      Basically *any* system that generates and store *lots* of energy should be treated with substantial respect

  24. Anonymous Coward
    Thumb Up

    "Piping round superheated steam is dangerous"

    AC thanks JS19 for the two posts.

    Supeheated steam may well be potentially dangerous; I would recommend treating it with considerable respect, but surely on the whole superheated steam engineering is well understood, and tried tested and proven, e.g. in decades worth of GW-scale power stations around the world, both fossil fired and otherwise. And in various other industries too.

    Wrt hydrogen storage + shipment: both California and Iceland had proposals (and trials) where hydrogen formed a significant part of the energy distribution network (audience reminder: hydrogen is not an energy source in the same way as fossil fuels). BMW even made a "production" hydrogen car. Were all these ventures doomed to technological failure from the start, or were there other issues e.g. Iceland trial's reliance on well known green pioneer, er Shell?

    "The other big problem is waste. No real problem for desertec as all the materials can be recycled but a *big* one for nuclear. Not the tech, but who *pays* for it. My *impression* (and I'd love to be corrected on this) is that nuclear operators think the host *government* should pick up the bill for this. If so this is *exactly* the sort of private profit/public cost deal UK banks seem to have been enjoying. Is a business plan that *depends* on HMG picking up the tab for the disposal for all this crap "sound"?"

    Indeed. Nuclear power is only economically interesting if you're willing to fiddle the economics so the taxpayer guarantees the expensive bits. In a fair market, why should only nuclear get this privilege?

    "Depending on the salt selected the heat store would be quite hazardous due to temperature and chemical nastiness to the workforce. "

    But probably nothing that hasn't routinely been deployed in chemical factories around the UK and elsewhere (probably on a slightly smaller scale though).

    "the new generation French reactor has hit trouble due to non compliant concrete and cracks in the structure (it's still under construction)."

    Indeed. Olkiluoto and Flamanville mentioned earlier are two contrasting examples of the alleged same design (though the control system design at Olkiluoto is not yet approved so how they can be declared the same in anything other than outline is troubling). Flamanville in France is seemingly doing OK. Olkiluoto is a well documented disaster, including the concrete issues you mention and the control-system design issues and massive cost/timescale issues and...

  25. John Smith 19 Gold badge
    Happy

    AC@09:28

    "Wrt hydrogen storage + shipment: both California and Iceland had proposals (and trials) where hydrogen formed a significant part of the energy distribution network (audience reminder: hydrogen is not an energy source in the same way as fossil fuels). BMW even made a "production" hydrogen car. Were all these ventures doomed to technological failure from the start, or were there other issues e.g. Iceland trial's reliance on well known green pioneer, er Shell?"

    Firstly Iceland is a state of 300k people. California is a state whose GDP would put it at *least* in the turnover of the top 20 world economies. Both are energy rich either by oil and wind or geothermal and hydroelectricity.

    That's important because the issues around H2 are only *partly* technological. They can be solved on a (relatively) small scale. The problem is how much *money* you're prepared to invest to do so on a *large* scale.

    I note the Iceland scheme was kick started by a Chemistry professor. Chemists *love* the simplicity of H2 combustion (barely 19 species to model H2/O2 combustion IIRC).

    The California plans talks about a minimum of 50 filling stations but not *how* they make their Hydrogen. One of the US hydrogen reports indicates there is 1 million miles of natural gas pipeline versus 1200 miles of Hydrogen. This is not surprising. Room temp H2 piping is welded stainless steel. IE It's *very* expensive relative to normal gas piping. If you want to send as a liquid you're looking at "Vacuum jacketed" IE *concentric* welded stainless steel lines with a vacuum between. Liquifying it take 1/3 of the energy carried per unit mas of H2 your liquifying.

    That suggests they will make H2 by catalytic processing of natural gas, a *highly* energy intensive process to produce the "clean" fuel. They will then take a shed load *more* energy either to compress it to a reasonable volume or liquify it.

    My point is that Hydrogen has a *lot* of problems which make the idea of it as a "drop in" replacement for *any* fuel ridiculous.

    Key point. Hydrogen is an *exceptionally* awkward fuel to make, transport and store due to its natural *physical* properties, which don't change unless you live somewhere like Pluto. It has *very* poor energy *density*. Ikg of gasoline gives c62Mj at roughly 1.4l. 1Kg of H2 gives c112Mj at c12.9l (*If* it's at -253c), but as you've spent 1/3 of that to liquify it in the first place. 20% more energy at only 820% more volume.

    Desertec is attractive because it works *with* existing distribution networks, not against them. It uses pedestrian (but *very* large scale) technology to deliver a cost *effective* solution to the problem on a large scale.

    If you ignore economics almost *any* scheme is viable on a small scale. However if it's not economic to begin with there is *no* incentive to grow and it will remain a dependent on (massive) state intervention.

    You have to be clear *what* problem you are trying to solve. Call me an arrogant b*£$"$d but I think they have it wrong. Liquids fuels are easy to handle, store and move and allow vehicles to be "recharged" quickly. It is *possible* to make a steam powered car (and in the UK the steam powered speed record was recently broken), but why would you *want* to?

    IMHO the ideal system would be a flywheel storage drive EV (no loss of capacity aging modes). However for the near term a system which uses the sun to generate electricity to charge a hybrid flywheel/fuel cell vehicle fueled by a renewable liquid fuel or near cryogen (LNG, LPG, Methanol perhaps). The concern is not so much CO2 in Earth's atmosphere, it's the *rising* level of CO2. Re-cycling that CO2 would slow it's growth and be relatively easy to do using *existing* infrastructure.

  26. Anonymous Coward
    Flame

    ecology ....

    The ecology of some north-African desert hellwhole can only be improved by covering it over with black glass slabs. Ground temps go from 130-F to 110-F and snarky local vipers, Taliban wannabez & drop-dead scorpions can turn-off the AC !

    Think I'm gonna gag at feckin-A euro-sensitive mud_hut lovers. Better to ram bitch-Gaia in the *zzwhole and get on with your AC_moderated business.

  27. John Smith 19 Gold badge
    Joke

    AC@12:20

    "The ecology of some north-African desert hellwhole can only be improved by covering it over with black glass slabs. Ground temps go from 130-F to 110-F and snarky local vipers, Taliban wannabez & drop-dead scorpions can turn-off the AC !

    Think I'm gonna gag at feckin-A euro-sensitive mud_hut lovers. Better to ram bitch-Gaia in the *zzwhole and get on with your AC_moderated business."

    Good evening Mr Cheney. So glad you could join us. Thank you for that *very* succinct description of recent American policy on this matter.

This topic is closed for new posts.

Other stories you might like