Even with all the new storage technologies, it is still better to reduce demand.
Kris De Decker’s Low Tech Magazine is one of the most thoughtful and interesting places on the web to find original and controversial thinking about energy and technology. His latest post is typical: a detailed criticism of renewable power, titled, How (Not) to Run a Modern Society on Solar and Wind Power Alone.
In it, he looks at the variability of wind and sun, and notes:
While the potential of wind and solar energy is more than sufficient to supply the electricity demand of industrial societies, these resources are only available intermittently. To ensure that supply always meets demand, a renewable power grid needs an oversized power generation and transmission capacity of up to ten times the peak demand. It also requires a balancing capacity of fossil fuel power plants, or its equivalent in energy storage.
And that is the rub -- we are still burning coal, natural gas and biomass to fill in the gaps, although batteries, pumped storage and other technologies are becoming more common.
De Decker looks in detail at the strategies that are proposed to deal with intermittency of renewable:
First, we could count on a backup infrastructure of dispatchable fossil fuel power plants to supply electricity when there's not enough renewable energy available. Second, we could oversize the renewable generation capacity, adjusting it to the worst case scenario. Third, we could connect geographically dispersed renewable energy sources to smooth out variations in power production. Fourth, we could store surplus electricity for use in times when solar and/or wind resources are low or absent.
But none of these are without problems. And the fourth, storage of surplus energy, the one we all dream of with Tesla’s batteries and air balloons and trains running up hills, is perhaps the most problematic. Lots of people believe that this is the answer, and it is the main reason that many feel that Kris is out of touch, saying “this article is 30 years behind the state of the art.”
The energy required to build and maintain the storage infrastructure and the extra renewable power plants need to be taken into account when conducting a life cycle analysis of a renewable power grid. In fact, research has shown that it can be more energy efficient to curtail renewable power from wind turbines than to store it, because the energy needed to manufacture storage and operate it (which involves charge-discharge losses) surpasses the energy that is lost through curtailment.
Or more simply, it takes so much energy to build the storage, and the losses incurred due to inefficiencies are so big, that it may be more efficient not to bother.
This is not so different from what I and a few others have been saying, as noted in my post The grid is not a bank. I suggested that instead of investing so much in increasing renewable energy supply, we should be doing everything we can to reduce demand -- for instance, building our homes as super-insulated thermal batteries that require very little heat at all and can go for days without much heat input because they are so well insulated. It is also why I promote bicycles as the ultimate form of transportation technology, because they use very little energy, take very little space, and make the rider healthier.
Ultimately we need radical building and transportation efficiency more than we need expanded renewable energy sources and storage: why build it if you don’t actually need it?
In the end, Kris De Decker calls for a fifth strategy that’s not much different from what I call for: Adjusting demand to supply. He is saving most of his ammo for the next post, but I suspect he is going to go all 19th century on us, concluding:
Before the Industrial Revolution, both industry and transportation were largely dependent on intermittent renewable energy sources. The variability in the supply was almost entirely solved by adjusting energy demand. For example, windmills and sailing boats only operated when the wind was blowing. In the next article, I will explain how this historical approach could be successfully applied to modern industry and cargo transportation.
I’m all for 19th century technology too. Fridtjof Nansen demonstrated how super-insulating his boat with a foot of cork let him drift around the Arctic for three years starting in 1893 without ever getting cold. (He even had a wind turbine to generate electricity for lighting.) Bicycles were terrific transportation before the cars pushed them off the roads. Both technologies demonstrate how to get by while consuming very little energy.
The key point that we both agree with is that reducing demand is more effective (and a lot less costly) than increasing supply. Or as TreeHugger emeritus Ruben Anderson notes on Facebook,
Solar panels, windmills, electric cars! There is no need to change anything, in fact, we can all have more stuff!… There is only one route out of this, and we are going down that road whether we like it or not. We will use less stuff, we will have less stuff, and we will use less energy.
Harsh but true.