Friday, March 26, 2010

Interesting data from the Guardian

Since the Guardian posted some (misleading) criticism of feed-in tariffs a few weeks ago, I have been monitoring the website more closely. Today, the British paper published an interesting review of a Pew report, which found that, as the paper stresses, China has overtaken US in terms of investments in "clean tech."

But the figures used actually show how uninformed the Guardian is. For instance, the data on "clean tech" investments is linked in a table entitled "Renewable energy investment by country." But clean tech is not the same as renewable energy. Investments in carbon capture and storage, for instance, are generally also included as clean tech, as are innovative insulation systems, to name just two examples that are clearly not renewable energy. (I have not yet read the Pew report, so I do not know exactly what the study defines as clean tech.)

The Guardian then conflates "energy" with "power" when it gives us, in the same table,

  • Renewable Energy Capacity, GigaWatts
  • Percentage total power, %

We see that Brazil has made quite a lot of investments in renewables -- nearly twice as much as Germany -- but only has a third of Germany's "renewable power." Why is that? Perhaps it is because Brazil has invested so much in ethanol, which it produces from sugarcane, for use as motive fuel. In other words, Brazil produces renewable fuel more than renewable electricity. But the folks at the Guardian do not seem to understand the issue well enough to present the data accurately.


The paper then writes, "Pew have kindly shared the data with us - what can you do with it?" Answer: I would completely throw away the report in the Guardian and have to start over with the Pew data from scratch.

Also, I would have to point out something that I have said at conferences on renewables before (and it really angers people). When we count generating capacity for wind turbines and solar and compare the figure to the generating capacity from nuclear, natural gas, and coal plants, we inflate the figures for renewables. For instance, Pew reports that 36 percent of Germany's electricity generation capacity is already renewable, but the country actually gets far less than half of that percentage from renewables.

(Update: the exact figure for the share of renewable electricity was 16.1 percent in 2009 in Germany. And while the Guardian/Pew puts the figure for investments in renewables in Germany at 4.3 billion, my German source has the figure at 17.7 billion in 2009.)

The reason is quite simple -- while coal and nuclear plants run at 60-70% and 90-95% capacity, with gas turbines being switched on and off more often, wind turbines hardly ever generate more than 30 percent of their rated capacity on the average and actually come in below 20 percent in Germany. The figure is similar for photovoltaics.

Proponents of renewables get really upset when I say this, but I don't see why -- it's a simple fact. If we are going to convince the few remaining doubters, we need to speak the truth. And the truth is that wind and solar allow us to make use of a resource we lose every day - the wind and solar energy we get today. If we don't use it, we lose it.

Coal, nuclear, and gas plants are different. They run on resources we would not otherwise lose. We only lose them when we use them.

But you won't hear that from the Guardian, where the understanding of energy matters seems to be quite shallow.

1 comment:

  1. On the edge of the Taklamakan desert in Western China,I recently drove through the 'worlds largest windfarm'. This succeeds for 3 reasons (1) It's desert, so no-one can complain (2) It's permanently windy (3) The electricity generated can be used to irrigate the nearby cotton fields on land that would otherwise be desert, also to power factories which process the cotton & even produce garments, so obviating the need for long distance power lines.
    Why do so many commenters always assume that the Chinese government only ever ride rough-shod over their own people ?

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