The writing’s on the dam wall

With consents granted to the Arnold hydro scheme (45MW), and now a new proposal for a dam on coal-mining land on the Stockton plateau (25MW), the primary rationale for Meridian’s Mokihinui Hydro Proposal (MHP) has been removed.

Meridian’s proposed MHP cites these benefits:

The Mokihinui Hydro Proposal would:

  1. produce between 310 and 360 gigawatt hours (GWh) per year of renewable electricity generation.
  2. meet the current and immediate future electricity needs of the South Island’s West Coast
  3. provide security of supply to the West Coast region
  4. on average - reduce the nodal price on the West Coast in the setting of wholesale electricity prices
  5. significantly reduce transmission losses currently experienced which can be as much as 50% at peak demand times
  6. provide an upgrade of and new sections of the 16km degraded walking track from near the entrance of the Mokihinui Gorge to the Mokihinui Forks area.
  7. Include the formation of a Trust with other individuals and interested parties to investigate the potential to provide a further walking track that would link the Mokihinui Forks to the Lyell.

    Points 2 to 5 all assume that there is no West Coast alternatives to generate the required power. The West Coast’s peak demand is about 65MW and projected to increase to around 80-90MW in the near future. Current supply capacity on the Coast is 18.5MW, but the addition of Arnold makes 63.5MW, and a new Stockton dam (subject to due diligence on the environmental impact of that proposal) would cover the projected growth in demand. And this doesn’t even include efficiency and co-generation options in the coal and dairy industries on the Coast, which are the primary drivers of growing demand. Hence, points 2-5 can be met without destroying the Mokihinui.

    Points 6 and 7 are misnomers. The track upgrade and developments can be done without the dam, and the Trust is proceeding on this basis already.

    Only point 1 remains valid. Inherent in any new project is new generation, that’s self-evident, but the question is at what cost, fiscally and environmentally. The environmental cost of MHP is huge, and the economics of other renewables nationwide are comparable, so that is where some national strategic planning of new generation would be useful. Add to this that the proposed National Policy Statement on renewable energy recognises the inherent irreversibility of a large hydro dam, and well, it’s not rocket science that the MHP is a non-essential and environmentally undesirable proposal.

    Hence if we proceed with the MHP, we are simply sacrificing premium biodiversity, a pristine wild river, and our conservation credibility, unnecessarily and irreversibly.

    Saving the Mokihinui was not just an election year campaign for the Greens, it continues to be top of mind, and now we have two new South Island-based MPs to help fight it. Hopefully Meridian will see the writing on the dam wall and gracefully withdraw.

    Meyt says

    58 Responses to “The writing’s on the dam wall”

    1. dbuckley Says:

      So, once again, when the Green Party are faced with the decision between another hydro scheme, and the default scenario of more thermal generation (especially in a moratorium free world, the thermal she’s a-comin’), which scheme do the GP choose to support…? Why, more thermal, of course. Impressive.

      Planet Earth to Greens: We need all the hydro we can get to displace (or at least contain the growth of) CO2 emitting thermal stations.

      And please dont mix your units - how is someone supposed to compare a 45MW plant with a 310GWh/Yr? It seems that the comparitive number for Mokihinui from the links supplied above is 65-85MW.

    2. bliss Says:

      Because more Hydro (and more thermal) is not needed.

      Current wants are much higher than needs, because of inefficiencies, and future needs can be met from renewable alternatives.

      peace
      W

    3. big bro Says:

      The writing’s on the dam wall

      It sure is, 119/7 and we are going to lose by an innings.

    4. peterquixote Says:

      fwwog.
      we told you to affiliate with NAT progressive fwwog,
      what happened fwwog;
      answer here fwwog

    5. peterquixote Says:

      go on fwwog,
      answer to your people

    6. Shunda barunda Says:

      The fact is, with the abundant rainfall on the West Coast there should be a nett export of hydro power to the national grid. We need as many efficient hydro schemes as we can get from this region. Fish passes can be built, and hydro lakes on the West Coast can certainly harbour a massive eel population, as well as other native species.

    7. fastbike Says:

      pq

      we told you to affiliate with NAT progressive

      Who is we ?

    8. IceBaby Says:

      >>Because more Hydro (and more thermal) is not needed.

      Yes it is.

      Easy to make these arguments, eh.

      I’ll add a few facts from the EIA:

      “Over the next 25 years, the world will become increasingly dependent on electricity to meet its energy needs. Electricity is expected to remain the fastest-growing form of end-use energy worldwide through 2030, as it has been over the past several decades. Nearly one-half of the projected increase in energy consumption worldwide from 2005 to 2030 is attributed to electricity generation in the IEO2008 reference case. Since 1990, growth in net generation has outpaced the growth in total energy consumption (2.9 percent per year and 1.9 percent per year, respectively), and generation is expected to increase at an average annual rate of 2.6 percent through 2030 as the growth in demand for electricity continues to outpace growth in total energy use (Figure 52). ”

      And what happens if oil has indeed peaked?

    9. Roman Says:

      I see.. so the Greens dont want public transport powered by electricity. Interesting.
      Bring back Project Aqua I say.

    10. dbuckley Says:

      Bliss: Please dont consider this an ad hominem attack because its not, you were simply the first to go for the rhetoric, and its time for my tea.

      There is this theory amongst environmentalists (including Green Party members) that somehow there is this magic “renewables” thing which we can have as an alternative to [whatever is on the table today].

      The simple fact of the matter is that it aint so. Whats on the table is whats on the table, and today the options are build more hydro or build more thermal. (Sorry for shouting, but) THEY ARE THE ONLY CHOICES AVAILABLE. There is nothing else.

      So its time to be either a pragmatic environmentalist, vote for reducing emissions and support the hydro schemes, or, the only thing left is the defacto choice which the anti-hydro folks mandate, which is more emitting thermal stations.

      Thats it. No other choices. Time to stand up and be counted. For or against more emitting thermal stations. Thats the only choice. We’re getting more generation come what may.

      I’m just glad there are companies out there who want to build more hydro.

    11. kahikatea Says:

      Shunda barunda Says:
      December 1st, 2008 at 4:58 pm

      > The fact is, with the abundant rainfall on the West Coast there should be a nett export of hydro power to the national grid.

      I would have thought so, too. Any idea why it isn’t?

    12. kahikatea Says:

      dbuckley Says:
      December 1st, 2008 at 6:01 pm

      > The simple fact of the matter is that it aint so. Whats on the table is whats on the table, and today the options are build more hydro or build more thermal. (Sorry for shouting, but) THEY ARE THE ONLY CHOICES AVAILABLE. There is nothing else.

      I’m not sure how you work that out. surely there are four options on the table at the moment - more hydro, more thermal, more wind farms and energy efficiency improvements like the one the new government is planning to scrap.

    13. frog Says:

      Wrong kahikatea. There is one more very important choice that thermal scaremongers like dbuckley conveniently forget. Geothermal. We have more than enough to meet our baseload needs for years. We should switch some of our older thermal to high efficiency gas peakers, which we will need, and put Huntly into dry year reserve. Sorry dbuckley, there are many more options available and they are cheaper than new baseload thermal.

    14. kahikatea Says:

      frog Says:
      December 1st, 2008 at 6:52 pm

      > Wrong kahikatea. There is one more very important choice that thermal scaremongers like dbuckley conveniently forget. Geothermal.

      Thanks Frog.

      I don’t normally like people telling me I’m wrong, but I’ll make an exception in this case.

    15. dbuckley Says:

      To frog and kahikatea I say (with apologies to Jerry Maguire) Show me the money and show me the resource consents. When you’ve got both of them, then you are somewhere near an option on the table that can be discussed. No money and no resource consents - no relevance, you dont get to pass go.

      But even if you do whistle up some more geothermal, I’m entirely happy with that, but its not an alternative to hydro; its an “as well as”.

      As I’ve wibbled on at length previously, power stations fueled by stuff you dont need to pay for, and in particular not gas, in the long term are the only cost effective options. In the shorter term, people with money find thermal power stations almost irrestible. And remember, its only people with money that get to build power stations.

      But I do like the fact I’ve been labelled a (and its a term I haven’t heard before) “thermal scaremonger” - that absolutely rocks, especially since its absolutely true, in both senses of the phrase. Perhaps if there were a few more of us then we’d have less thermal generation proposed. Isn’t that what a Green Party should be advocating?

    16. frog Says:

      dbuckley - truth be told I had put the word troll in there, but thought it wasn’t appropriate in the circumstance. I’ll link to the list of consents tomorrow if I can find it. The Contact Energy site alone should have about three. The EC’s research lists more though…

      I still assert that it is not a case of “as well as”. We can go a massive distance (and time) on geothermal, wind and that cheapest of all sources - energy efficiency.

    17. dbuckley Says:

      I dont disagree with some of what you say frog, but my underlying point stands - if you (by which I mean, of course, the Green Party) support blocking hydro then thermal will expand to fill the load. Thus (argumentatively, I grant you) to be a any renewables blocker is to be an emissions supporter.

      This is especially true as (a) we have the thermal stations today, (b) we have a fair bit of coal for them, and (c) there is a shift towards the greater use of electricity, just for one example, clean air in Christchurch removing (for good reasons) wood burners [carbon neutral] with heat pumps.

      Historically NZ was 100% hydro, and you can arithmetically consider the gap from where we were then to where we are now as Huntly (almost). The less renewable generation, the more Huntly. Huntly is (as I’m sure you know) NZs biggest single power station, and as a taget to replace with renewables is a tall order. This is why we need all the renewables we can get. Arnold and Stockton between them are less than one tenth of the job.

      And of all the things I am, and especially on energy, I am not a troll.

      It frustrates me enormously when the supposedly environmentally aware party of NZ supports legitimising emissions with the ETS (with a two thirds vote by people who expressed an interest), rather than actually reducing emissions by way of using available renewable energy sources that someone is actually ready to build.

    18. Shunda barunda Says:

      “I still assert that it is not a case of “as well as”. We can go a massive distance (and time) on geothermal, wind and that cheapest of all sources - energy efficiency.”

      Ugly wind farms and expensive geothermal will never match the efficency and reliability of well designed hydro schemes.
      NZ is uniqely placed to utilise hydro in a greater way without the problems some other countries experience.
      As far as sustainability goes hydro is the best, no mass of expensive high maintenance parts of wind farms or tidal, and none of the polution of thermal. Geothermal is an option but it can never offer the potential energy generation of hydro, it is a supplement supply at best.
      Using gravity to generate power just makes sense in a country with lots of mountains an abundant rainfall.

    19. Trevor29 Says:

      Shunda barunda - it seems at least some of the major power companies, and NZE some 50 years ago disagree with you about the economics of geothermal. It may have something to do with the high reliability of geothermal - usually over 95% capacity factor.

      Trevor.

    20. Shunda barunda Says:

      Geothermal generation should be embraced, but it will never match the versatility or simplicity of hydro. Geothermal can never come close to offering us what hydro can in this country.

    21. Shunda barunda Says:

      From Wiki
      “To boost the “renewables” ratio, geothermal power is often counted as renewable, even though the geothermal heat reservoirs are depleted (observably so at Wairakei, the longest-running), and, they are not emissions-free. For example, the Ngawha geothermal field emits an unusually high amount of CO2 (350 tonnes CO2 per GWh [15]) and the geothermal fields plus natural hot springs draining to the Waikato river deliver sufficient arsenic to render the water unsafe to drink without special treatment[citation needed]. Re-injection of the waste geothermal fluid can reduce these problems (even extending the life of the field), but involves additional expense.”

      Geothermal is not the magic cure to our energy needs and is doubtful if it is even truly sustainable, unlike hydro which has zero emmisions and zero pollution.
      Infact hydro can actually increase the water quality of some rivers.

    22. Kevyn Says:

      Shunda, Do you know how they keep the beer cold at the Birdsville races?

      https://www.epa.qld.gov.au/publications/p00834aa.pdf/Birdsville_geothe rmal_power_station.pdf

    23. bjchip Says:

      Frog

      I disagree. We need every KWH of renewable juice we can generate and we need it quickly.

      There are limits to geothermal. The rate of extraction is limited in any given field. It is only available in one area… not South Island’s west coast. The transmission losses and power pylons are another struggle and the vulnerability of the plants to tectonic activity in the region (and it is not unknown) means that relying on them alone for base power could be extremely costly to the country if a large quake hits that region.

      I hesitated long before weighing in here. This is perhaps our most problematical internal conflict. Preservation of the snail-darter and a wild river vs preservation of human civilization is what it comes down to when you strip away the irrelevancies. Which is not to say that THIS project tips the balance but the philosophical approach that denies its legitimacy may well do so.

      I’ve never, in the past 5 years, noticed that Greens here in NZ allowed ANY hydro power project to occur without protest. Possibly something that entails a modification to an existing plant has been let through, but automatic opposition to hydro projects seems to be the rule.

      Dbuckley is wrong. We don’t need to replace Huntly, we need to replace it 4 or 5 times over. We need power to replace petrol, to replace diesel buses and trains, to replace natural gas, and surpluses to allow industry to continue. Shunda is right and in this case very right. The west coast of South Island SHOULD be exporting power considering its average annual rainfall and altitude.

      We need ALL of them Frog… every renewable source we can muster, and one of our advantages here in NZ is that we get a massive amount of rainfall in the mountains of the South Island west coast. Liquid solar.

      We do not want to be a banana republic.
      (Build Absolutely Nothing Anywhere Near Anything)

      respectfully
      BJ

    24. IceBaby Says:

      You know the Greens have lost the plot completely when they object to hydro. And you wonder why people don’t take you seriously?

      BJ is right. Not only do we need more power, we will need a LOT more.

    25. turnip28 Says:

      Well thats because the green party is full of people who are
      anti-civilization. They want us all to start living in trees and eat leaves.

      BJ is the one green who consistently makes sense a pity the party ignores him so much.

      NZ needs a lot of POWER from a variety of sources. You also can’t build the future with technology from the future. Since you need to plan and start building today for tomorrow then you need to use the technology that exists today. You can’t sit on your arse NIMBYing everything claiming to be waiting for a technology to appear that will solve everything as it isn’t going to happen.

    26. dbuckley Says:

      Applause to BJ - And yes, I am wrong in that respect, but we have to start somewhere, and today we are going backwards. It is this anti-some-renewables-’cos-we-dont-like-them attitude that allows BB to wade in and say “build more thermal” and most of the time, thats exactly what will happen.

    27. kjuv Says:

      >>Thats it. No other choices. Time to stand up and be counted. For or against more emitting thermal stations. Thats the only choice. We’re getting more generation come what may.

      Well there is actually; but it seems that it is beyond human comprehension: embrase a nil-growth society. Indeed it is a combination of (for this country) three general strategies, namely (1) Reduce demand, (2) Decrease turnover of consumer products by, amongst other actions, removing the ‘built in obsolescence’ and superficial upgrades of products (3) Stabilise the population. Some other countries have the even greater challenge of decreasing their population

    28. frog Says:

      Why the assumption that we are anti hydro? Do you see any objection in this post to the Arnold or the Stockton schemes? No. Rather a stated preference for them over the Mokihinui scheme. Even you BJ are saying that the Greens come out against every hydro scheme. It’s simply not true.

      We do need power, we do need a lot. Nor are we counting on some magic bullet technology that turnip28 talks about. Only the growth at all costs cornucopians are counting on that.

      Shunda - geothermal only gets run down when it is used unwisely/unsustainably, as was the case with Wairakei, which is by the way, being completely redesigned and rebuilt in a way that will allow it to go on indefinitely and reduce emissions, countering all your objections.

      Hydro is not emissions free either, yet considered renewable, just like geothermal. We are fast running out of rivers to dam, but we are not running out of geothermal opportunity here, not by a long shot. No doubt we will some day, but it’s a long way off and we have a bunch of other hurdles, like climate change to deal with before we get there.

    29. Shunda barunda Says:

      “Hydro is not emissions free either, yet considered renewable”

      Where do the emissions come from, farting trustpower technicians?

    30. Sam Buchanan Says:

      “a wild river vs preservation of human civilization is what it comes down to when you strip away the irrelevancies. ”

      Wow. Civilisation can’t continue without oodles more power! Does that mean we were all living in a state of barbarism in say, 1950, when there was lots less power available?

    31. IceBaby Says:

      >>but it seems that it is beyond human comprehension: embrase a nil-growth society…Decrease turnover of consumer products

      Are the Greens a non-Christian version of the Amish?

      “The Amish (pronounced /ˈɑːmɪʃ/) are members of an Anabaptist Christian denomination, best known for simple living, plain dress and resisting modern conveniences”.

      Where will all the power come from when we replace petrol transport with electric?

      No, we do not all want to go by train or bus, nor can we, or should we.
      We’ll insist on power generation, and we’ll get it.

    32. Shunda barunda Says:

      “Does that mean we were all living in a state of barbarism in say, 1950, when there was lots less power available”

      No, it means people lived in cold houses, burnt massive amounts of coal and rata trees in inefficient open fire places. They didn’t have heat pumps, oil column heaters and all the electric appliances we have today, they also didn’t have 4.5 million people to share the power with.
      This whole anti hydro stance is something NZ greenies inherit from overseas activists. This stance proves that much of the “green” movement is not capable of rational thought towards sustainability at a local level and can not be trusted to deliver a truly sustainable future for NZ.

    33. dbuckley Says:

      The underlying problem for the Green Party is as BJChip notes - a lot of GP folks see the “small” issues, which they believe to be very important, yet can’t see that in being proponents of small issues they are creating big issues.

      Environment (big E) versus environment (little e).

      The Green Party got caught with theirn trousers round their ankles over Aqua big time. Perhaps they have learned something from this: if they were to say “We support the Arnold, Stockton and Mokihinui hydro schemes” then thermal scaremongers like me would be put in our place. But as the original post states: “Inherent in any new project is new generation, that’s self-evident, but the question is at what cost, fiscally and environmentally.“. I would argue (supported by frog in his most recent post) the carbon game (a/k/a climate change) is the only game in town.

    34. bjchip Says:

      Frog - What I said was what I see. I can be more specific.

      Greens don’t ever propose ANY dams.

      Greens apparently allow some smaller dams to go ahead.

      Greens oppose all big projects almost automatically.

      My perception of course is subject to the fact that here we only hear about the ones that are opposed. The ones that are quietly allowed through may escape notice… however, the issue you raise, that we’re running out of good hydro locations, is real enough. Eliminating good hydro locations to preserve small things thus becomes LESS wise.

      The Emissions Cost of building the dam is not negligible. It is however, amortized over the life of the dam. A couple of hundred years one hopes.

      respectfully
      BJ

      Sam - Civilization works by using power. Most of what we have and use is built using power. There’s no substitute for it in nature and there’s no substitute for it in economics. The more energy a civilization controls and can turn into entropy above its base necessary energy, the better off each member of that civilization is. Lowering the base necessary is conservation and it is good. It isn’t enough. We’ve gotten used to our cheap oil and cheap gas and cheap coal… we need to wean ourselves from those and that means replacing them with renewable power. It isn’t just our current electrical demand, but also every non-renewable we use that we need to replace.

      Exactly right. We need oodles more power. To replace the power we won’t be able to get from Saudi Arabia and to replace the power we should not use because it brings on global warming.

      respectfully
      BJ

    35. Trevor29 Says:

      BJCHIP said:
      “We do not want to be a banana republic.
      (Build Absolutely Nothing Anywhere Near Anything)”

      I hadn’t heard that one before - I like it :)

      Trevor.

    36. Trevor29 Says:

      Kevyn, if you read the article that you linked to more closely, you will see that they use the diesel generators at high demand periods - summer and during the Birdsville races.

      Sounds like they need to expand their geothermal plant a bit more and power it during the day and early evening from solar thermal and from the geothermal hot water the rest of the time.

      Trevor.

    37. Trevor29 Says:

      Rain isn’t the only thing the We(s)t Coast has plenty of. They also have a good wave energy resource.

      Exporting power from there has the same problems of large transmission losses. The aim should be an approximate power balance.

      Note that much of the rain that falls on the West Coast ends up in the East Coast Rivers.

      Trevor.

    38. jh Says:

      When I drive through the MacKenzie Country I wonder how we paid for the canals etc back then and why we “need” a greater population now etc.

      PS Peter Jackson is going to remake the Dambusters around Benmore.

    39. bjchip Says:

      Trevor

      I don’t agree. Generate as much as we can and power there is cheap. We can use it to make methane, or we can price it according to the surplus. It will necessarily be a matter of exporting power as much as importing energy intensive industry from places where power is generated from coal or oil.

      Displacement of carbon generation takes place due to the economics of the resource. Whether we build massive transmission lines or not.

      One has to think it through to the other side… the construction of hydro resources (and all renewable resources) inevitably makes us better off.

      BJ

    40. jh Says:

      With regard to the type of thinking behind the notion that continual economic growth is possible/ desirable I found this article has some relevance:

      The era that defined Wall Street is finally, officially over. Michael Lewis, who chronicled its excess in Liar’s Poker, returns to his old haunt to figure out what went wrong.
      http://tinyurl.com/64mm8l
      ht the visible hand

    41. Trevor29 Says:

      The West Coast is not the only area with good wave energy potential - the South Island’s South Coast is another, and handy to the Aluminium smelter and the transmission lines linking it and Manapouri to the rest of teh South Island. The West Coast lacks infrastructure - the main power feed is via Stoke, near Nelson! The rugged nature of the Southern Alps discourages building power lines across from Canterbury.

      Exporting power (e.g. in the form of Urea or other fertilizers) isn’t something I had thought of for the West Coast. (I think that was what BJ was suggesting.)

      Methane generation for local consumption on the West Coast may not be economical because of the small scale, but would certainly tie in with balancing the amount of local generation with demand. Having said that, it might be a good place to build a trial plant? (Once more generation is installed of course.)

      I’m largely in agreement with you BJ - we should be building more generation using our renewable resources. We just disagree a little on where and what.

      Trevor.

    42. Shunda barunda Says:

      ” The rugged nature of the Southern Alps discourages building power lines across from Canterbury.”

      Actually the main power line comes through from Canterbury, I remember it being threatened by a wild fire near Mt horrible a few years back.
      The transmission distance from the West coast to Christchurch is still close enough to export power from west to east without too much transmission loss.
      The future of hydro may be with a larger number of smaller schemes like the stockton option Frog blogged on above. This scheme could generate 25MW of power from just 4-9 cumecs of water going through the system, with a peak output of 50MW during heavy rain, this is a remarkable amount of power for such a low water requirement.
      The West coast terrain is suitable for a number of similar schemes and they have very low environmental impact. Hydro is miles in front as far as the most cost effective method for sustainable power generation.

    43. Kevyn Says:

      Shunda asked “Hydro is not emissions free either, yet considered renewable” Where do the emissions come from, farting trustpower technicians?

      There are two sources of significant GHG emissions from all new dams. The CO2 emitted during the manyfacture of the cement, unless it is an earth dam of course.
      The methane emitted by the anaerobic decomposition of the flora inundated by the dam.

      Very much an AGW Catch 22. Big emissions now when we can least afford, small emissions later when it may be too late.

    44. Kevyn Says:

      Trevor, I never let the facts get in the way of a good link teaser. However, in this case my only defense to your response is to provide the link to the original post from The Oil Drum that led to the PDF link that I gave. That post discusses the very issues you mention - or more precisely the newer more efficient technology that is being considered to increase the generating capacity:
      http://anz.theoildrum.com/node/4802#more

    45. Kevyn Says:

      Kahikatea asked: > The fact is, with the abundant rainfall on the West Coast there should be a nett export of hydro power to the national grid.

      I would have thought so, too. Any idea why it isn’t?

      The simple answer is in this comparison of one rainfall monitoring site on the west coast and seven on the West Coast. Please note that West Coast sites that receive more rain than the Auckland site are all located on the Great Alpine Fault. The title Great is reserved for faults with a history of generating M8+ quakes.

      Waitakere Ranges records a mean annual rainfall of 2030mm.

      Karamea River at Gorge records a mean annual rainfall of 2760mm and daily falls of up to 140mm.

      Inangahua River at Landing records a mean annual rainfall of 2460mm and daily falls of up to 170mm.

      Ahaura River at Gorge records a mean annual rainfall of 2450mm and daily falls of up to 140mm.

      Hokitika River at Colliers Creek records a mean annual rainfall of 7600mm and daily falls of up to 600mm.

      Whataroa at State Highway 6 Bridge records a mean annual rainfall of 5690mm and daily falls of up to 320mm.

      Waiho at Franz Josef records a mean annual rainfall of approximately 5500mm and daily falls of up to 400mm.

      Haast River at Roaring Billy records a mean annual rainfall of 5750mm and daily falls of up to 400mm.

    46. Kevyn Says:

      Source for the above is
      http://www.wcrc.govt.nz/river_level_rainfall/about/

    47. Trevor29 Says:

      http://www.gridnewzealand.co.nz/f70,3566/3566_transmission-map-si.pdf

      shows a 50 or 66kV line from Hororata to Kumara but 110kV and 220kV lines from Dobson through Inangahua and Kikiwa and down to Islington. Kikiwa is South-West of Stoke, so I was a little out saying it went through Stoke - only the Nelson circuit goes through Stoke.

      I stand by my comment that the MAIN feed is not over the alps.

      Trevor.

    48. Shunda barunda Says:

      Sorry Trevor, I didn’t realise that. Does that mean most power to the West Coast first goes up the east coast, across to Nelson and then down to the West coast?
      If true that is an incredible transmission length!!

    49. Shunda barunda Says:

      “Very much an AGW Catch 22. Big emissions now when we can least afford, small emissions later when it may be too late.”

      That is rediculous.

    50. bjchip Says:

      Frog

      If the emissions for the concrete to build a dam that prevents emissions for 100 years are too much for the planet to bear then we’re finished before we start and any OTHER measures are completely irrelevant.

      I don’t think this is the case.

      The concrete is being made, currently made in places that use fossil fuels to cook it. We could make it using electrical ovens. Heck, if the Aussies wanted they could concentrate solar to cook the stuff.

      Concrete=Bad is not an equation of necessity. It is a perception of the current system and true as long as the material is made in coal fired ovens. Not necessarily true, just true now.

      Moreover, concrete is going to be made anyway. It’ll just be put to less productive (from a deep green perspective) uses.

      respectfully
      BJ

    51. Trevor29 Says:

      Everyone knows that the West Coast gets a lot of rain. However this does not necessarily mean that hydro power stations there will be cheap. I suspect that the costs mount up. I can believe that one power company might avoid investing there even if it was a cheap option. I find it harder to believe that NZE and all the power companies formed since NZE was split up would have avoided hydro schemes there if they were very cheap.

      I can think of several reasons why they might be more expensive than alternatives:

      One possibility is that the river flows there tend to be low most of the time, but with frequent high peaks. Without storage lakes to even out this flow, most of the water would need to be diverted down spillways.

      Related to this would be the possibility that a significant amount of rocks and stones are washed down - that could cause all sorts of problems.

      I don’t know. I’m not that sort of engineer and I’m not really familiar with the area. Still I’m glad that the power company engineers are now considering the possibilities.

      Trevor.

    52. Shunda barunda Says:

      From what I understand you are pretty much on the button there Trevor. West Coast rivers are considered to be “flashy” rivers, in reference to the potential rapid rise in water after heavy rain that occurs regularly.
      We also experience some massive peak flood flows on the larger rivers, the Buller being the largest river in NZ for peak flood discharge at a massive 8000 cumecs (50 year flood) and the Grey not far behind at 6100 cumecs. 100 year floods are even bigger!!.
      No doubt this would pose some difficult engineering for hydro schemes to spill such a massive amount of water, even the Clutha and Waikato rivers never get near that peak flood discharge in a 100 year event.

    53. Kevyn Says:

      Shunda, It’s only ridiculous if you don’t understand the persistence of CO2 in the atmosphere. Methane is bit more complex. Bur as BJ pointed out changing the way cement is cooked can eliminate the carbon emissions from that source. In fact that might be a more cost-effrctive way of utilising the world’s abundant low temperature geothermal and concentrated solar potential instead of converting it to electricity.

    54. Trevor29 Says:

      Kevyn - the geothermal idea isn’t a workable option. Geothermal sources are only a few hundred degrees. Cement requires 1200-1400 degrees C:
      http://www.nzic.org.nz/ChemProcesses/inorganic/9B.pdf

      I don’t see why concentrated solar wouldn’t work.

      Trevor.

    55. Trevor29 Says:

      Why is the Stockton Plateau Hydro Project being set up to generate baseload energy - 25MW 24/7? The area has 50% transmission losses at times of peak demand so it needs generation that can help meet peak demand. The Stockton scheme has 78 hectares of reservoir storage and they are talking of 50MW peak generation in times of flooding. Surely they should aim to run closer to 50MW at times of high demand and under 25MW at other times?

      Trevor.

    56. Trevor29 Says:

      Two lakes, one above the other, with a hydro generator linking them…

      That just about describes a pumped hydro storage system!

      I wonder if it has occurred to them? It probably wouldn’t store a lot - perhaps 100MWH - but it would reduce the transmission losses and allow us to make use of the “must-run” generation available.

      Trevor.

    57. Trevor29 Says:

      An area served by long transmission lines with a peaky power demand and some local generation - sounds like the sort of place that could benefit from a vanadium redox battery system.

      http://www.vrbpower.com/

      Trevor.

    58. Trevor29 Says:

      With the above-average wave energy crashing on their shores, perhaps the West Coast would also suit LIMPET
      http://www.wavegen.co.uk/

      Trevor.

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