February 05, 2014 | Viv Forbes

Green energy not fit for purpose

Germany’s wind and solar power generation came to a standstill in late 2013. More than 23,000 wind turbines ran out of wind and most of the one million photovoltaic systems ran out of sunlight. For a whole week, coal nuclear and gas-powered plants generated an estimated 95 percent of Germany’s electricity.

Britain has 3,500 wind turbines, but during a period of extreme cold they produced just 1.8% of UK’s electricity. But, gluttons for punishment, politicians intend building more.

When electricity demand peaked at the height of the recent heatwave in Southern Australia, the total power output from the fleet of wind farms across Victoria and South Australia was almost zero. Solar panels worked at their peak for a short time during the heat of the afternoon, but waned as the sun moved on and smokiness increased.

At dinner time on any still, cold winter night, when all suburban stoves, lights, TV’s and heaters need power, solar panels sit in the dark, powerless. And the idle wind turbines are probably drawing power from the grid for heating, lubrication, electro-magnets, hydraulics and start-up.

Despite the expenditure of trillions of dollars on conferences, green energy subsidies, research, carbon taxes, carbon trading, solar and wind subsidies, plant construction, additional transmission lines and back-up power, wind and solar only produce a derisory share of world energy (“zero” to the nearest whole number).

We keep hearing how “research” will solve the key green energy problems, but no amount of research can alter the fact that solar energy will always be variable, intermittent and dilute.

Even if solar panels collected 100% of the solar energy that fell on them, and no dust or snow ever covered the panels, the output is always variable and intermittent, with the rise and fall of the sun, the long night and the variable clouds, snow and dust.

Similarly the wind is variable, often too weak, sometimes too strong, and even when it is just right, there may be no demand for that surge of power. Germany has 23,000 wind turbines – they produce an average of about 17% of their installed capacity; on some days, they harvest nothing except subsidies (and they are good at that).

And crucially, both wind and solar energy are very dilute, so large areas of land are required to collect significant energy and to build the spider-web of roads and transmission lines required to connect to each other and to the grid. Solar panels rob green plants underneath of their sunlight. Wind turbines annoy neighbours with their noise, devalue their properties and slice up eagles, bats and migrating birds. These are very significant human and environmental costs never mentioned by green energy disciples and promoters.

No amount of research can change the key intermittent and dilute nature of green energy. We should stop wasting ever-increasing amounts of money on pointless research.

Even if we invented magic batteries (small with massive capacity, low cost, no energy losses and everlasting life), the green energy plants would still need to spend over 60% of the energy they generate to charge the batteries in order to produce 24/7 power.

There are places when green energy is appropriate and useful, and people should be free to use it at their own expense. But for grid power, it is not fit-for-purpose.

All of this explains why Green Germany is now using more coal than it did in 2009 and its power supply is more expensive and less reliable.

Posted by Viv Forbes at 10:34 am | Comments (13) |
Filed under: Environment


  1. Nearly a decade ago, the CSIRO did a study and estimated that even if there were sufficient renewable generation to supply power for the whole country, there would need to be 90% of the capacity covered by fossil fuel generators to cover the times when there was little wind at night.

    Comment by Jeff Hosking — February 5, 2014 @ 1:28 pm

  2. Do you have a copy of that report Jeff, or a link to it?

    Comment by Viv Forbes — February 5, 2014 @ 8:17 pm

  3. Sorry Viv, but trying to search for a decade old article is like looking for a needle in a haystack.

    However, having worked as a power systems electrical engineer for nearly a decade, distribution and generation systems are designed for peak periods when spot prices are 40x or more those of off peak periods, which typically occurs between 5pm and 8pm.

    It doesn’t take much to realise that at this time, solar is of little use, and wind is unreliable. As the promise of Hot Rocks fades, the back bone of generation then falls to coal with gas for peaks, and renewables as a feed in.

    Comment by Jeff Hosking — February 6, 2014 @ 4:31 am

  4. Such a pity its so negative. All we need it to spend a lot more on battery research and the problem will be solved sensibly. My garage roof already supplies all my electricity and I am only dependent on the grid for the timing of the supply. Batteries to cover 4 – 7 days consumption is all that is necessary

    Comment by Dickybird — February 6, 2014 @ 10:13 am

  5. It is quite amazing that after all the research, all the subsidies, all the ‘global warming’ legislation and dedication of masses of people by governments around the world, including the U.N. – attending “workshops”, “conferences” and other direct government rep to government rep “consultations” – that the gross contribution to the world’s energy by wind and solar is still less than 1%. I wonder what the nett benefit to the environment would be if the CO2 production connected with all the above mentioned activities were totaled and deducted from the claimed benefits?

    Comment by Mike Williamson — February 6, 2014 @ 12:07 pm

  6. Hello Viv,

    During the week-beginning January 13, NEM-wide demand peaked at 33,769.54 megawatts at the Dispatch Interval 16:30 (AEST) on 16/01/2014. At this time, the sum output of wind energy was 710.42 megawatts (about 28% of total possible output).

    From the Monday to the Friday inclusive, the minimum sum output of wind farms across the NEM was 92 megawatts.

    Here’s a chart displaying total NEM demand, total possible wind output, and actual wind output, over the week of the heatwave:


    AEMO’s wind forecasts accurately predicted the output of wind farms, well in advance. If the integration of wind energy cause any energy market issues during the week, I’d be curious for you to point them out.


    Comment by Ketan Joshi — February 7, 2014 @ 10:07 am

  7. Hello Ketan

    “Figures supplied by the Australian Energy Market Operator show that between 11.30am and 4pm on Wednesday, as demand hit a daily peak of 33,029 megawatts nationally, wind’s share of supply fell as low as 0.3 per cent. When the electricity price peaked at $6213 in South Australian on Wednesday in the half-hour to 4pm, wind was contributing 0.7 per cent to total demand.”
    Graham Lloyd, The Australian, 18 January 2014.

    Wind is about as predictable as the weather, and this variability always adds management complexity and operational cost to the grid.

    And wind is intermittent with considerable periods when its output is zero. Therefore it must have 100% backup, which means that the capital spent on wind is totally unnecessary. Backup must be from a “grid-ready” power station – gas, hydro, nuclear, geothermal or coal.

    And because the wind output can and does cease suddenly, it needs continuously available backup which is always costly because of the variable and intermittent operation of the system. Even though the wind is free, total operating costs of the grid have risen significantly with green power.

    The bigger the wind share of the grid, the worse the management problems become. Outages and power fluctuations become more common as the wind proportion in the grid increases. German refineries were damaged recently because voltage dropped severely for just a second.

    Here is a good summary of the problems with Green energy in Germany.

    Why make the same mistakes here?

    Viv Forbes

    Comment by Viv Forbes — February 7, 2014 @ 1:08 pm

  8. Viv,

    Wind was indeed muted during that specific day. You made reference to the ‘height of the recent heatwave’, which as you know, lasted longer than one day.

    Does it seem logical, then, to consider peak demand for the duration of the heatwave, rather than specifically selecting a day with lower wind output?

    I’m also curious in which you can provide an example in which the output of wind has ‘ceased suddenly’, in the same way a 500 megawatt coal-fired power station did during the week of the heatwave.


    Comment by Ketan Joshi — February 7, 2014 @ 1:14 pm

  9. You appear to plagiarise Lloyd at the Australian, who is a critic and serial misleader. Your credibility is shot unless you open up and acknowledge your sources.

    No primary sources here at all, unlike analysts at Reneweconomy, say. Just regurgitating cherry picked bits, even when they are wrong. Such is the denial tactic.

    Ketan disproves the Lloyd contention that you borrowed. And your excuses are weak – the phrase “height of the recent heat wave” is clear in its intention.

    The “wind needs 100% backup” is crap if it implies that equivalent new backup capacity needs to be added when wind is added. There is nearly always “back up” capacity in the system, needed for peaks and/or failure in generating units.

    During the last heatwave, apparently all peaking plants were on for about 1 hour only. Even when a unit at Loy Yang A went down (so much for reliability of fossil fuels – suddenly 450 MW was gone). Quite likely thanks to solar and some wind.

    And you are dishonest in pretending that green energy is only wind. This presumably is to deny the real impact rooftop photovoltaic panels had in moderating the peaks during the last heatwave.

    And storage is coming…

    Comment by NW — February 7, 2014 @ 2:30 pm

  10. Ketan,

    Wind can produce a lot of power or nearly nothing, and generation is determined by demand. If wind / solar cannot be determined ahead of time, the fossil fuel generator need to be ready, which means you are paying for them anyway.

    Comment by Jeff Hosking — February 7, 2014 @ 4:28 pm

  11. Hi Ketan,

    That graph belongs to a blog post by some shyster who does a cherry pick to misrepresent what Lloyd’s and Forbe’s position is. If you actually look at the graph you’ll see that on two of the days of the heatwave, including the hottest day, which by definition must be the peak, when demand peaked wind output was virtually zero.

    This is not a hard ask for any upper-primary or lower secondary student to have enough graphmanship to work that out.

    It illustrates the problems of having a sensible conversation in this area with so many people committed to second rate technologies that they rush to the web with poor, or dishonest, analysis.

    Comment by Graham — February 7, 2014 @ 10:51 pm

  12. I’ve had a closer look at the blog post associated with the graph – so you are the “shyster”? Sorry. I try not to use emotive terms about posters on the site. However, you really need to lift your game. Especially as you boast a science degree. It makes the analysis much worse than I thought. You should be able to read a graph by now.

    Comment by Graham — February 8, 2014 @ 8:29 am

  13. Hey Graham,

    That’s okay, no offence taken 🙂

    I determined the maximum quantity of operational demand by using the data point itself, rather than reading it off a chart through visual inspection, or inferring it from average temperature.

    Determining maxima is something I learnt to do in high school 😉

    Comment by Ketan Joshi — February 8, 2014 @ 11:00 am

RSS feed for comments on this post.

Sorry, the comment form is closed at this time.