Sustainable Energy NZ #9 – Here Comes the Sum – what are renewables worth?

Welcome to the ninth post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. Today we’re summarising the numbers on the various renewable energy options in New Zealand (and finding they’re more than sufficient!). For the background to the work please our introductory post here. Also check out our earlier posts on the potential of hydro power,  geothermal and wind, and the summary on the big three. More recently we’ve dealt with solar, biofuels, marine and waste energy. Note: the units are in kWh/day/person – ie. if you ran a 40W lightbulb for 24 hours, it’d take ~1 kWh over the space of a day. We then divide it by person to give you a sense of the scale of the resource proportionate to the size of the population. Be sure to check out the methodology. For reference – we’re looking to replace around 55 kWh/d/p of energy currently generated by fossil fuels. 

So we’ve gone through the various renewable energy options over the last week or so. So where does this leave us for increased generation potential among renewable options? The affordable, mature technologies are hydro, geothermal, wind, waste gas, solar heating and biofuel. Large-scale solar and marine technologies are really promising options for the future but cannot be realistically considered now.

Fig.1 summarises the current and potential future amount of energy generated in NZ from the various renewable sources discussed above. The numbers used are conservative, allocating only relatively small areas to solar in the distant future. New Zealand is energy-rich but every option using renewable sources will have its own problems.


  • Current consumer energy use is 88kWh/d/p, of which 32 is from renewable sources. 50% of energy use is from petroleum.
  • These numbers are for current population (4.4 million). If the population grows to 5 million by 2050 as projected, then the numbers should be scaled back by 9/10.
  • The estimate for biofuel is based on minimal encroachment onto food producing land. Using all arable land for biofuel instead would deliver 43kWh/d/p.

And finally a word about Nuclear Energy

Nuclear energy is not a renewable resource but MacKay argues that it is possibly a sustainable energy source, and certainly it could be an alternative to lots of windmills and dams. The issues associated with nuclear energy are dealt with at length in MacKay’s book and don’t need further repetition here. For a New Zealand perspective, we would note that we don’t have any commercial uranium deposits, we are prone to earthquakes and tsunamis with similar risks to Fukushima and that commercial technologies for truly sustainable nuclear energy production are still in the future. For the moment, New Zealand has other renewable options.

And that ends this first part of the series. Next up, we’ll be looking at what options exist for reducing our energy footprint, and then looking at what a realistic plan might be for New Zealand. Check in for the next post — coming soon.


Oliver and Phil

Supplementary Readings

We’ve tried to include supplementary reading during these posts, and this one is no different. UCSD professor Tom Murphy, author of the excellent site Do The Math, has done a similar set of analysis (mainly concentrating on the USA) and come out with the following Alternative Energy Matrix. It is well worth a read because the global scenario is a bit different from our own – the majority of the world’s population don’t live on a island with a very temperate climate, low population density and plenty of energy options.

28 thoughts on “Sustainable Energy NZ #9 – Here Comes the Sum – what are renewables worth?”

  1. I’m glad to see that your “Alternative Energy Matrix” has a fairly major downer on wind, like a large percentage of the people who have to deal with this issue.

  2. Hmm, missing from the Alternative Energy matrix too is a bit on long term damage to the environment.

    andyS – these articles are about NZ. Wind farms here are unsubsidized so have to compete on a level playing field with all other energy sources and yet going up fast. For a UK perspective, then stick with MacKay.

    1. Hmm, missing from the Alternative Energy matrix too is a bit on long term damage to the environment.

      I consider wind farms to be long term damage to the environment.

        1. Given that wind turbines use a massive amount of concrete, and destroy the landscape, kill birds and bats etc etc, I don’t think there is any environmental benefit to wind energy at all.

          There is very little evidence that they actually reduce CO2 emissions anyway.

          In the UK, there are over 250 anti-wind groups across the country. Scotland and Wales are being smashed up by industrial wind development.
          Many of these development are in semi-wilderness areas.
          In the area that my parents used to live, they are even planning to build a wind farm in the middle of the Southern Upland Way, a popular walking track. Even the tourism board are complaining about this now. Fancy a wind farm in the middle of the Routeburn maybe?

          There were 1500 people turned up at an anti-wind protest in Wales. Hundreds of people turned up to protest about wind at the recent SNP conference in Perth. Some of the demonstrators were as old as 70 and had never been on a protest before. Some of the MSPs and SNP members swore and shouted abuse at these people, supposedly their democratically elected representatives.

          Wind energy is a scam, and I will continue to treat anyone who promotes it with the contempt they deserve

          1. So mass-species extinctions from wind mills? These comments express the opinion that you dont like looking at windmills but are not data. All forms of energy consume resources, concrete etc, especially mining. Ratios of energy in/out are useful (80:1 for wind from memory) as are lifetime emission 5-8g/kWh Wang and Sun 2012. Wind mills being unpopular does not make them a scam.

            And no, I would not build them on Routeburn. The analysis here is based on excluding all protected landscapes.

            I fully accept that the situation, economics and environment might be different in Britain, but for NZ, wind is a good option. We certainly have plenty of it.

            1. Wind is a “good option” for NZ?

              Maybe Facebook shares are a “good option” for NZ too. If the market turns against wind (which it appears to have done) then the market is very unlikely to invest in the only country that doesn’t heavily subsidise it.

            2. Hi Phil
              andyS has regurgitated these claims many times. It appears that every time they are confronted with objective evidence demonstrating the merit of adding wind power to the grid andyS gets frustrated and starts typing ‘birdchoppers’ and the like, as you see above.
              Throw in some dodgy man bites dog claims from the telegraph and mail and andyS comes full circle again.
              andyS does not like wind turbines. Next!

            3. A market turns against something when it fails to make a profit. Not a problem for any wind company here and hard to imagine what competing energy source would make it so.

              I can see little point in rant or opinions that are not supported by data.

        2. Anyway, it looks like the UK is throwing in the towel

          Death knell for wind farms: ‘Enough is Enough’ says minister
          Wind farms have been “peppered” across Britain without enough consideration for the countryside and people’s homes, a senior Conservative energy minister admitted last night as he warned “enough is enough”.

          1. Anyway, it looks like the UK is throwing in the towel

            One conservative ministers loggerheads opinion = the UK is abandoning wind energy?
            I guess your wishful thinking is gone in overdrive….

            Andy: You will be treated with the contempt you deserve for regurgitating the lies of the anti-wind lobby here at nauseam despite the fact that countless attempts have been made to point you to the evidence that you deny.

            Life Cycle CO2 emissions of various energy sources

            1. He is the minister who has just ordered a moratorium on any new onshore wind permits in the UK.

              He has just effectively killed off the wind “industry”, as so eloquently put by Booker.

              You can treat me with any amount of contempt you want Thomas.

              The wind industry was always a scam. Good riddance to bad rubbish.

            2. Plus it would seem that one ministers opinion does not imply policy being actually made… perhaps has the Daily Fail paid homage to its name once again?
              Despite the ramblings of the right wing rag of the UK the Financial Times just today reports an entirely different picture:
              Wind farm approvals rise to record levels

            3. And to rub it in:

              The UK government remains committed to its goal of almost tripling the amount of power the country gets from onshore wind farms by 2020 was confirmed by John Hayes, the Minister for Energy.

              as reported in The Telegraph today.

              As usual, a brief fact check of Andy’s comments is always worth a while…..

            4. a brief fact check of Andy’s comments

              Aw c’mon. When has one of andy’s comments ever actually contained a fact?

            5. The film “Lost Horizons” produced by Ben Pile, can be watched here


              It describes how wind energy is destroying Britain’s communities and coastlines.

              Not that anyone here cares, of course. You are “environmentalists”

          2. Phil

            I can see little point in rant or opinions that are not supported by data.

            Well, speaking of data, it was me that screen grabbed the NETA website to show energy output from the entire UK wind fleet at 0.0%. I sent that to Booker and it made it into a story in the Telegraph.

            So I do try to back up my claims with facts rather than the propaganda and glossy brochures that the wind lobby are so fond of

            Anyway, I don’t really care if you want to chop up NZ with wind turbines. It will be your legacy. We have lots of brown field sites like North Canterbury and the Wairarapa that no one really cares about, They are excellent sites to put these useless hill ornaments.

            1. Andy, please take your anti-wind zealotry somewhere else, please. It’s tiresome, boring, repetitive and mostly wrong.

            2. That is relevant how? What I wanted was data to back your assertions that building windmills here would be a “scam” (given there is no subsidy), that the power produced was a CO2 intensive as alternatives, or that they did significant damage to ecosystems compared to alternatives.

              That you dont like looking at them is clear but as far as I can see your other objections are not based on data and manufactured to back an anti-wind position based on visual values alone. By all means advocate for alternatives if you can find them. Personally, I think UK should be looking at advanced nuclear designs.

              However, visual values fall a long way behind ecosystem damage to me.

            3. Phil, I have been over this so many times that I can’t really be bothered any more.

              [Neither can I. Enough. GR]

            4. If I remember correctly, your initial boast about this was the day at the Olympics when the sailing was cancelled and the ocean at Weymouth was like glass; that is pretty rare. How many days and nights did you sit staring at the computer screen with your finger hovering over the PrtSc key? That is dedication to the Cause bordering on zealotry.

            5. SimonP November 1, 2012 at 2:02 pm

              If I remember correctly, your initial boast about this was the day at the Olympics when the sailing was cancelled and the ocean at Weymouth was like glass; that is pretty rare

              Yiu do not remember correctly, I never mentioned the Olympics at all.

              In fact I was quite planned about it. I saw a large blocking high moving across the UK and figured that there would likely be a period of little or no wind. I was “lucky” that the time I got was 12MW output for the entire UK wind fleet, which registers as 0.0% on NETA.

              If you watch the Lost Horizons movie I posted you will see a graph showing that these days are not infrequent.

            6. andyS is cherry picking as usual, either that or being dishonest, I can’t tell which.

              I just checked the NETA web page and found that for the past 24 hours wind produced 5.6% of total energy in the UK. I also found that the output from wind farms was at a 44% capacity factor. Who would have thought wind was so useful after reading all the rubbish andyS spews out about it.

              No wonder the majority of intelligent people using this blog refer to how dishonest he is, he proves us correct with just about everything he posts.

            7. Wow; what a pairing! You’re certainly every bit as well-informed, honest and reliable as Booker. Buzzards of a feather…

              I, for one, would be happy to hear no more of andy’s dishonest and tendentious whining on this topic.

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