Reports about new record shares of renewable power are understandably celebratory, but they also confuse the public – and even experts. What’s worse, these peaks are an indication of solar’s limits without storage. I’m not sure that something to celebrate. At least we can go much further with wind power.
If you haven’t already heard the news, “Germany produces half of energy with solar” – at least, that’s what the website The Local would have us believe (incidentally, don’t click on the link unless you want several ads to blast you with audio, but here it is).
Of course, by “energy”, the journalist means electricity only. And the figures reported by Fraunhofer ISE are preliminary: a record 24.24 GW for one hour on Friday, June 6, followed by 23.1 GW briefly on Monday, June 9.
The latter occurred on a public holiday (Pentecost Monday), so that amount of solar was reportedly enough to meet 50 percent of peak power demand briefly. However, other data do not confirm that outcome. The data used by Agora Energiewende have solar peaking at below 23 GW on June 9 with domestic power consumption at nearly 54 GW. So solar made up at most 43 percent that day depending on what figures you use. (Fraunhofer will not publish its full estimate for this month until next month.)
Some prominent people (who not only should know better, but probably do) are nonetheless firing off tweets that overstate the case; perhaps it is a natural outcome of being limited to 140 characters.
Germany produces 50% of its energy from solar. If only the Kochs weren’t in the oil business, we could too. http://t.co/ULMnfigVnG
— Bruce Bartlett (@BruceBartlett) June 24, 2014
Nonetheless, some comparisons are unfair, such as when this prominent Dutchman puts Germany share of solar energy at 50 percent, compared to “only 0.2 percent” in the US.
Half of Germany is Powered by #Solar #Energy (and U.S. only 0.2%) http://t.co/3mzB9hz4TY pic.twitter.com/HklVRYvJ6Z
— Alexander Verbeek (@Alex_Verbeek) June 20, 2014
Here, Meneer Verbeek unfairly compares a peak solar power production record in Germany to the annual average in the US – not cool.
But even people like Al Gore get the story completely wrong when they have the space to get things right. In along article published this week at Rolling Stone, Gore claims that “Germany… now generates 37 percent of its daily electricity from wind and solar.” In reality, Germany gets only a third of that amount – closer to 13 percent. Gore Is simply confusing peaks and averages.
With all of these knowledgeable people getting the soundbite wrong, it’s no wonder we end up with claims like the one below in reaction to an article at Think Progress based, alas, on Bernard Chabot’s analysis we published here.
I tried to explain the issue carefully over at EnergyTransition.de, but unfortunately the article from here focusing on the raw data – without so much embedded information – went viral.
Interestingly, Ireland recently saw its share of wind power peak at 50 percent of power demand, an issue that went largely unreported (why is everyone so focused on Germany?). “On average,” as this report explains, “wind energy supplied 23 percent of the electricity market in the December 2013 to May 2014 period.”
If we return to solar in Germany, we see that PV made up just over five percent of domestic demand last year. Assuming it increases to six percent in 2014, we now have solar peaking at half of demand but only making up a small sliver of the total share. The limits of solar in Germany without storage are coming fast.
If we double the amount of solar in Germany, we end up with peaks at 100 percent of demand, which will completely wipe out not only baseload plants (which must run), but also whatever wind power and biomass we happen to have at the time. In other words, Germany will need to start storing or simply losing solar power when PV makes up a mere 10 percent of demand. Compare that to wind in Ireland, and you see how much further you can go.
In Germany, the situation with wind is similar. Last December, we had around one third wind power for roughly a 24-hour timeframe. Wind power makes up nearly 9 percent of German power supply. Triple that, and you can get a quarter of your power from wind without storage or curtailment.
In other words, we can go at least twice as far with wind as we can with solar in countries like Germany and Ireland, which have higher power demand in the winter than in the summer (in many parts of the US, the opposite is true, so the potential of solar is much greater).
And incidentally, in the Agora chart above, did you notice that at 9 PM on June 7 we had around 9.4 GW of renewable power, though demand was still slightly above 58 GW. German conventional power plants were running at 44.5 GW at the time, and the country was a net importer for a few hours that evening. Those who celebrate these record peaks would be well advised to look for the nearby lows, which are often just a couple of days away.
Source: Renewables International. Reproduced with permission.
