Is there a solar revolution? Time for data, not adjectives

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Solar power is disruptive, growing exponentially, fill in the blanks. This is what you will believe if you spend too much time reading optimistic articles on clean tech websites, and less time looking at actual statistics for solar generation.

In reality solar power’s heavily subsidized growth is nowhere close to being the revolutionary force some of its advocates claim it already is. It is also not growing exponentially, as anyone could see if they checked the meaning of the term exponential growth and actual statistics for year on year growth rates.

Globally, solar grew by 93% in 2011, 60% in 2012, 39% in 2013, and 38% in 2014. Meanwhile, in the countries with the most developed solar sectors, absolute growth has in fact slowed.

Germany added 7.5 and 7.6 GW of new capacity in 2011 and 2012 respectively. In 2013 and 2014 the figures had gone down to 3.3 and 1.9 GW. The same goes for Italy, where new capacity additions went from 9.3 to 0.38 GW between 2011 and 2014.

In fact, the current growth of European solar is not even vaguely exponential. Instead, growth is declining overall. In 2011, 22.4 GW was added throughout Europe; in 2012 17.4 GW was added, in 2013 10.4 GW was added, and in 2014 7.2 GW was added. Absolute growth of solar capacity in Europe is now one third of what it what it was in 2011.

Anyone confidently predicting continued exponential growth of solar will have a hard time accounting for the actual decline in growth in Europe.

Growth of solar can be put in further perspective by comparing the annual growth (in TWh) with the total electricity consumption of a country. Let’s imagine that in a single year a country went from 0 to 1% of electricity generation being from solar panels. That would mean it would take roughly 100 years to get to 100% solar.

Obvious caveat: we don’t know what to do when the sun goes down, but you get the thrust.

So, how quickly is solar growing globally? Below is a chart showing the top 25 countries in terms of solar growth last year. Growth is measured by comparing absolute growth of solar (in TWh) with total electricity generation (in TWh).


Number 1 is Greece. Now, exactly why heavily indebted Greece is number one in the growth of a heavily subsidized source of energy generation can be debated, but the fact remains.

Most importantly, no major economy is above 1%. At current rates of solar additions they are all many many decades away from solar power taking over. And remember: many of these countries, e.g. Germany, are now seeing reduced rates of absolute solar additions.

Growth in solar energy in China now attracts a lot of optimistic headlines. However, the increase in solar energy last year represented only 0.2% of total electricity generation. In other words, if China kept increasing solar’s share at that rate it would take half a millennium to get to 100% solar electricity. Keep this in mind when you see misguided headlines about solar power having a major influence on Chinese air pollution.

Focusing on electricity generation alone of course is problematic. The underlying reason to switch to solar power is climate change. And the majority of fossil fuels are not used for generating electricity, but for heating, flying, shipping, making steel, and so on. What we really should look at is total energy consumption.

The growth of solar is much slower in terms of total primary energy consumption. Growth in solar in 2015 was less than 0.5% of total primary energy consumption in all major economies.

Top20growth_primThese numbers should make it clear how far we are away from a solar revolution. The figure for China and the US is 0.1%. If China and the US added solar at a rate ten times greater than they are today, then, it would take them a century to get to 100% solar.

In Germany, where a supposed solar revolution has occurred, the figure was 0.29%. 100% solar is a mere three centuries away in that high latitude, cloudy country……. where the sun still goes down.


16 thoughts on “Is there a solar revolution? Time for data, not adjectives

    Alexander Ač said:
    June 24, 2015 at 9:12 am


    you dimiss the joys of EXPONENTIAL growth 🙂 (just joking).

    With exponential growth (OR exponential price decrease) everything is possible. Its so easy and convenient to be optimist 🙂



    Arthur said:
    June 24, 2015 at 11:31 pm

    Simple and hard-hitting.
    Fix that typo!
    “Globally, solar grew by 93% in 2011, […2012,2013,…] and 38% in 201_2_”


    Arthur Yip said:
    June 25, 2015 at 5:15 am

    This post is a refreshing antidote to They assume/extrapolate how EU went from 24% -> 33% of electricity (when hydro and biomass is included) and then comment how going to 80% will not be a big deal…


      Robert Wilson said:
      June 25, 2015 at 8:43 am

      I tend to stop reading energy articles that feature the words “revolution”, “exponential”, or “disruptive”. They are 999 times out of a thousand completely uninformative.


    […] Reblogged from Robert Wilson’s site, Carbon Counter […]


    Brendon said:
    June 27, 2015 at 3:00 am

    Here is how the curve looks for total solar generation in the US. Looks vaguely exponential to me. While the TWh added/total TWhs for the US was 0.22 in 2014, in 2013 it was 0.12, and it was 0.06 in 2012. So each year saw a doubling in the percentage. At this rate, in about two years the US will be up over 1.0. Showing one year of data doesn’t show a trend.


      Robert Wilson said:
      June 27, 2015 at 8:25 am

      Did you bother reading the thing before creating this graphic? I discuss multiple years of growth rate, globally and in Europe. This is the second time you have responded – the first with a blog post – to things you just appeared to have skimmed through. It’s not as if I’m writing Finnegan’s Wake here.


        Brendon said:
        June 27, 2015 at 1:42 pm

        What exactly in my blog post or my comment do you disagree with? A slowing growth rate in Europe does not mean growth is slowing everywhere. Your post left out the US, which is seeing a doubling of the rate of growth compared with total consumption, as I pointed out. How would you describe the shape of the curve for the US?

        While you present one year of data for China, the ratio of new solar added to total consumption is actually growing each year, meaning you shouldn’t assume the current (or last year’s) growth rate in the future. Here is what the curve of solar generation looks like in China (via BP data).


        Robert Wilson said:
        June 27, 2015 at 1:47 pm

        This is tiresome. I suggest you take the time to read what people are actually arguing before commenting. I did not assume the current growth rate of anything would continue in future. Where you get this from is being me.


    Brendon said:
    June 27, 2015 at 2:19 pm

    “However, the increase in solar energy last year represented only 0.2% of total electricity generation. In other words, if China kept increasing solar’s share at that rate it would take half a millennium to get to 100% solar electricity”


      Brendon said:
      June 27, 2015 at 2:24 pm

      I’m also still wondering how you would characterize the shape of the growth curves in the US and China.


      Robert Wilson said:
      June 27, 2015 at 2:35 pm

      You read that as me assuming China will keep adding solar at current rates for half a millennium? I’m giving up here. Correcting your continued misunderstandings is not a worthwhile use of a Saturday afternoon.


        Jan Ziobro said:
        July 15, 2015 at 8:48 am

        Well I do not know if @Brendon did read that but I certainly did read that you assume “keep adding solar at current rates for half a millennium”. If you do linear extrapolation based on one year delta (addition) I assume that you do think that addition would be the same every year. Just reading your outrage on the comments it hit me that this was figure of speech to visualize quantity. Something like comparison to “football fields” when talking about area or “library of congress” when discussing data capacity. But if you do know that delta (addition) would not be the same each year such figure of speech is still dishonest and misleading.


        Robert Wilson said:
        July 15, 2015 at 9:05 am

        First rule of writing: Never second guess how literal minded your readers are.


    It's getting doomy out there | Bad Futurist said:
    June 30, 2015 at 6:49 pm

    […] growth in solar is slowing, not […]


    gbell12l said:
    July 2, 2015 at 5:59 am

    Can we please have fuller references? “Data source: BP” doesn’t help me recreate the results.


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