The curious math of Amory Lovins

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Do the math: simply repeating 2011’s renewable installations for three additional years, through 2014, would thus displace Germany’s entire pre-Fukushima nuclear output.

Or so claims Amory Lovins in a new piece about renewable energy in Germany. Anyone with even a passing knowledge of the level of nuclear power in Germany will recognise this claim is utter nonsense within about two seconds. However, since Lovins appears incapable or unwilling to do the basic arithmetic, let’s do it here. A couple of minutes on Google can find a summary of German solar and wind installations in 2011:


To make it terse: 7.5 GW of solar and 1.9 GW of wind was installed in 2011. The figures in Lovins piece show that nuclear power generated 130 TWh of juice in 2010, and this is in line with what the IEA says. How would the annual production of 2011’s new renewables installations compare?

7.5 GW of solar in one year (assuming a capacity factor of 10%, which is roughly the German average) would give us 6.6 TWh.

1.9 GW of wind in one year (assuming a capacity factor of 40%, the average is currently below 30% but I will be generous) would also give us another 6.6 TWh.

Added together we have a total of just over 13 TWh each year from Germany’s new renewables installations in 2011. So, it will take Germany at least 10 years at 2011’s build rate to displace their pre-Fukushima nuclear output with renewables. (note: 10 years of solar additions at 7.5 GW is probably Easter Bunny territory. This will result in over 100 GW of solar on the grid, and will result in Germany having more solar (and wind) than it knows what to do with on a sunny day.)

So, the basic math on Germany’s nuclear phaseout is very clear, yet I suspect that Lovins will not be the last person to try to deny it.

[Update: Amory Lovins has “corrected” my errors in a comment over at Renewables International. Now, I have no problem admitting when I make mistakes and the above post includes one. I forgot to include the likes of new biomass plants in my analysis. This is correctly pointed out by Craig Morris in the article, so you should knock a couple of years off my conclusion.

On the other hand Lovins’ remark once again shows that he is not very good at arithmetic. He claims that Germany lost 41% of its nuclear production in 2011, whereas this is actually the lost capacity. This is the basis for his claim that Germany can replace its pre Fukushima nuclear output simply by repeating its 2011 renewables additions for 3 years. Here are the actual changes in nuclear output, from Lovins’ own piece:


This is a decline from about 130 to 100 TWh. So, the actual lost production is almost half of what Lovins’ imagines it to be. Also, if Lovins’ had paid a little attention to the statistics in his own posts he would recognise his error. He points out that renewables grew from 20 to 23% of German electricity supply in 2011. Adding three percent per year for four years only adds up to twelve percent, a good bit short of the twenty three percent nuclear was providing.

Lovins also inaccurately states in his comment at Renewables International “Since the calculation resulting in TWh / y is not GW, capacity factors are irrelevant to this hypothetical case’s outcome”. Given that his calculation for lost nuclear production was based purely on their capacities he perhaps should have paid a little attention to  capacity factors. All of the remaining nuclear plants in Germany have high capacity factors, almost always coming in above 80% for the year. The same cannot be said for the plants shut in 2011. These were mostly old plants running at very low capacity factors. For example the Bruensbuttal and Kruemel plants had not produced any electricity in the two years before Fukushima. This is why the percentage decline in nuclear production is about half of the decline in capacity.

I could go on, but I suspect the reader has got my point long ago.]


16 thoughts on “The curious math of Amory Lovins

    Samuel said:
    April 17, 2013 at 4:40 pm

    Well, in the same paragraph the guy is also saying that France is a net importer of German electricity, unable to understand the difference of grid flows at the border (when Germany is selling electricity to UK, Spain or Italy guess where the electricity is flowing through ?) and overall commercial output.
    So the actual fact is that contrarily to Mr Lovin statement France was a net Exporter of electricity in 2011 for an amount of 2.4TWh


      Samuel said:
      April 17, 2013 at 4:41 pm

      *2.4TWh was the balance of energy exported to Germany


        Bill Woods said:
        April 17, 2013 at 6:44 pm

        From ENTSO-E
        year FR→DE – DE→FR = net FR→DE (TW-h)
        2010 15.13 0.80 14.33
        2011 20.32 0.14 20.18
        2012 13.22 0.78 12.44


        Samuel said:
        April 17, 2013 at 7:58 pm

        Thanks for the source Bill, but there’s obviously something wrong here I got my figure from RTE (their 2011 report since it was the year used by Lovin for his idiotic statement). Have a look on their annual report [1] page 21.

        The ENTSO-E stats are providing the actual flows of electricity and not the contractual exchange. Between FR & DE the flow exchange should be positive in favor of Germany since they are still a net exporter to many european countries and using the French network for a part of these exports.



        jmdesp said:
        April 23, 2013 at 2:26 pm

        Samuel, the reported commercial exports are only between countries that share an electric frontier. Event if, once the connexion is saturated, they can make the exchange go through another country.


      Craig Morris (@PPchef) said:
      April 18, 2013 at 11:41 am

      Samuel, France is a net importer of power from Germany in terms of commercial flows (and I think you referred to the RTE report yourself below). France uses the German grid to sell power to Switzerland and Italy. A recent 99-page study (in English and German) went into the details, and I reviewed it starting here:

      The study found that the German grid is congested to the Southwest (where I live) with French exports to Switzerland and Italy, which is why the German power flows from the north to the south partly via its Eastern neighbors. But there was apparently no temporal correlation between surges of renewables and surges in these flows through Poland and the Czech Republic.

      By the way, where would I find information about how much power Germany sells to the UK and Spain?


        Samuel said:
        April 18, 2013 at 1:01 pm

        Hello Craig, you’re right for 2013. I read again Lovin’s paper and it was confusing. So I did a summary based on RTE data.
        2005 FR net importer 9.6 TWh from DE
        2006 FR net importer 5.6 TWh from DE
        2007 FR net importer 8.2 TWh from DE
        2008 FR net importer 12.6 TWh from DE
        2009 FR net importer 11.9 TWh from DE
        2010 FR net importer 6.7 TWh from DE
        2011 FR net exporter 2.4 TWh to DE
        2012 FR net importer 8.7 TWh to DE

        So, to sum up I had the very bad idea to pick the only year France was a net exporter… which makes Lovins statement actually correct.


        Craig Morris (@PPchef) said:
        April 24, 2013 at 12:00 pm

        Samuel, I think you and I should start a campaign for better information. In February, Portuguese Energy Minister complained about the French blocking grid expansions to allow more power to flow between the Iberian Peninsula and France. Doesn’t he know how much electricity goes from Germany through France into Spain? Obviously, grid connections between France and Spain are already sufficient for a lot of electricity; otherwise, what you’re complaining about – large amounts of power sold from Germany to Spain through France – wouldn’t even exist.


        Samuel said:
        April 25, 2013 at 10:40 am

        Never said DE was selling *huge* amounts to ES (ES has balanced exchanges of electricity), but it’s just a fact that DE being (or was, not sure anymore with their missing nuclear plants) the second exporter of electricity in EU after FR, when ES buy on the spot market they buy from DE also and not only from FR.
        As for PT, the issue is all those windfarms who are never producing when you expect them and like ES they would like to find a way to sell this surplus power.
        DK is fine because they can sell all their wind surges to SE & NO even if at a great loss. PT & ES are not so lucky, but I don’t see why FR should pay for the unaccounted cost of their windfarms.
        Also ironically the guys who are against any new lines accross the ES/FR border are the same greens who want windfarms.


      Craig Morris (@PPchef) said:
      April 23, 2013 at 9:08 am

      Samuel, you did not answer my question: where can I find information about how much electricity Germany sells to Spain via France?

      And again, if Germany sells any power to Spain, it has to go through France – or are you suggesting the German should expand their grid to Spain around France?

      The question is different for French exports to Italy and Switzerland, with which France has a common border. France sells power to both of these countries in excess of what it exports directly, with the remainder running through Germany. In other words, France uses the German grid to transport electricity it sells to Switzerland and Italy. I provide the link taking you to that study below.

      I don’t know why you speak of “2013”; my data do not concern this year. For years, France has been a net importer of German electricity (commercial) but has used the German grid to sell power to neighboring countries with which it shares a common border.


        Samuel said:
        April 23, 2013 at 10:10 am

        No idea, we just know that there’s a discrepancy between the contractual exchange (i,.e. paid electricity) and effective flows going through the lines.
        Problem is that entso-e[1] figures are wrong as I mentionned above to Bill. Since the figures for FR & DE are lower than the actual contractual exchanges.

        Regarding Spain, since the only way for Electricity is to come from France, it is certain that when ES purchase power from DE, the power is flowing through FR. UK & IT are probably less dependent to the FR grid, but most of their exchange capacity is also connected to it and the potential DE energy is very likely to flow through the FR grid again.



    quokka said:
    April 18, 2013 at 1:08 am

    According to Wikipedia, German electricity production from wind was 46,500 GWh in 2011 from an installed capacity of 29 GW. By my calculation that’s a capacity factor of about 18%. I’ve seen this figure for capacity factor quoted elsewhere. 30% is probably way too generous.


    Tom Bond said:
    April 18, 2013 at 8:51 am

    Data from German Department of Environment BMU 2011 renewal energy sources report confirms that wind’s installed energy capacity at the end of 2011 is 29GW and electricity production from wind was 46,500GWh for a capacity factor of 18%.
    Also of interest is solars installed capacity of 25GW producing 19,000GWh for a capacity factor of 9%. Biomass installed capacity was 6GW producing 41,000GWh for a capacity factor of almost 80%.


    Robert Wilson said:
    April 18, 2013 at 10:59 am

    quokka, Tom Bond

    30% is probably a better figure for new wind farms in Germany. The next few years will see a big increase in the number of offshore wind farms which will drive up the capacity factors.


      jmdesp said:
      April 23, 2013 at 2:13 pm

      Deployment of new offshore project is going very slowly at the moment in Germany since the utilities have little money left :
      And the grid problems are still not really resolved, so some think of reducing the offshore capacity instead.

      And it’s hard to be able to claim a precise number for how good the load factor will be in the German north sea.


    Colin said:
    April 24, 2013 at 10:35 pm

    Lovins’ claim seems to be based on a misinterpretation of his own figures. He bases it on the assumption that 41% of nuclear output was shutdown. But in fact it was 41% of nuclear *capacity* that was shutdown. However the most of that older capacity was underperforming. So shutting down 41% of the capacity only resulted in the output dropping by about 25%.

    In fact Lovins’ own graph bears this out. It clearly shows the drop in nuclear output in 2011 is obviously much less than 41%. Similarly the increase in renewables output in 2011 is obviously much less than a quarter of the pre-Fukushima nuclear output.


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