The BP Statistical Review of World Energy provides a lot of interesting data. Personally, I was interested in plotting the energy consumption by source as a function of time for different sources similar to:

enter image description here.

Looking into the BP report, there is for example Solar Consumption in EJ and also Solar Generation in TWh, respectively for each year. I seem to miss something fundamentally here, but why is the first larger than the latter?

As an example, take the Solar Consumption in EJ from 2021, which is for the total world 9.73 EJ. This calculates to $$\frac{9.73\cdot10^{18}\,\mathrm{Ws}}{3600\cdot1000} \approx 2701\,\mathrm{TWh}. $$

Looking again at the table, the Solar Generation in TWh for 2021 for the total world is 1032.5 TWh, so more than a factor of 2 lower. For me, it would make more sense if it would be the other way. So, obviously, I am missing something fundamental here. Any ideas?


1 Answer 1


From the first paragraph of the Methodology section:

Primary energy

Traditionally, in bp’s Statistical Review of World Energy, the primary energy of non-fossil based electricity (nuclear, hydro, wind, solar, geothermal, biomass in power and other renewables sources) has been calculated on an ‘input-equivalent’ basis – i.e. based on the equivalent amount of fossil fuel input required to generate that amount of electricity in a standard thermal power plant. For example, if nuclear power output for a country was 100 TWh, and the efficiency of a standard thermal power plant was 38%, the input- equivalent primary energy would be 100/0.38 = 263 TWh or about 0.95 EJ.

So, they quote the actual solar generation of 1032.5 TWh and the 'input-equivalent' consumption of about 1032.5 / 0.38 = 2717 TWh = 2717 / 278 EJ = 9.77 EJ. They likely use different efficiencies for different countries depending on the typical thermal plant technologies in each place, in which case their actual global total will be slightly different from these numbers. I must admit I can't see the Solar Consumption values in the pdf report I'm looking at, presumably you're quoting that number from another table they've provided.

  • 1
    $\begingroup$ Indeed, I overlooked that part - I was looking at the excel sheet and it was somewhat hidden there, looking at the pdf makes it more obvious . $\endgroup$
    – Alf
    Commented May 2, 2023 at 12:42

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