Following the Fukushima nuclear disaster, governments throughout the world started rethinking their relationship with nuclear power. One country did something about it. Germany announced in 2011 that they would be phasing out nuclear power in favor of clean, sustainable energy sources like wind and solar. The goal was to get a third of the country’s energy from sustainable sourced by the end of the decade. The German government remains resolute in their commitment to clean, non-nuclear energy, but the realities of available technology and infrastructure prove to be obstacles to reaching their goal.
Two challenges that clean, sustainable solar and wind energy compete against are nights and calm weather. Skeptics of sustainable wind and solar energy production have serious concerns about how location and condition-dependent forms of energy will power our grid. The challenge we face is that for our current grid, here in the U.S. and over in Europe, electricity is generated on-demand.
When the load on the grid increases, the electric generating companies crank out more electricity. When the load drops, production is dialed-back. This is easy enough to do when the source of your electricity is a fossil fuel like natural gas or coal, you cut the fuel supply and the plant produces less energy. When demand increases, you have the fuel you conserved on-hand for generating electricity. The energy storage technology is no more complex than a pile of coal outside the power plant. Literally. According to Joel Achenbach’s 2010 article in National Geographic, for the 21st Century economy, we need a 21st Century grid, and part of that is developing the technologies for storing sustainable energy.
With sun and wind, the technology for “piling” it for later use is more complex. We cannot dial-back the sun or turn down the wind and then revive the energy at a later time. The sun is shining and the wind is blowing now, whether we need the energy or not. Currently, Germany has the problem of generating too much energy from sustainable sources at times. According to the Deutsche-Welle article “Storage snags German clean energy boom” at times there is “so much wind energy on offer that wind turbines need to be turned off to prevent the grid from overloading.” In fossil-fuel terms, this would be like continuing to shovel coal into the furnace of a power plant, but take the generators off-line.
There are a few strategies showing promise for green energy storage. One involves diverting excess energy to pump water uphill into a reservoir for hydro-electric generation. According to Achenbach, the city of Fairbanks, Alaska has a battery the size of a football field. Flywheels and molten salt also show promise.
Advancements in energy storage need to catch up to technologies of energy capture. Until we can “pile up” the captured energy from sustainable sources, sustainable energy will be nothing more than a supplement to traditional generating methods.
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