The energy in the Sun is abundant, and is the long-term solution to humankind’s energy requirements. We currently face two challenges to harness it. The first is developing sufficiently dense batteries to smooth supply, and store it until we need it. We are making good progress with this although we are not there yet. However, we have been less successful with the base load to supplement it. To move on from relying on coal we need a new partner for solar.
The Enigma of Hydro Seemingly Beyond our Reach
On paper, hydropower seems the obvious answer. We release stored water to drive huge turbines during peak. Then we reverse the polarity and use base-load surplus during quiet times to put it back in storage.
The catch is, until now we have had to build large storage dams to create a sufficient head of pressure. The capital cost of this has been holding the solution back.
Could a Coal Mine Be a New Partner for Solar?
The idea sounds crazy at first, because coal is already a base load partner for solar. However engineers at the Prosper-Haniel coalmine in North Rhine Westphalia, Germany have been thinking laterally. Their company has been following coal seams since 1863, and has created a vast network of downward-sloping tunnels in the process. But it is facing a fresh challenge.
The mine is due to close in 2018 as it has become uneconomic. This could destroy the technically savvy community that grew up around it.
However they believe the downward-sloping tunnels could become a new partner for solar. They want to fill them with water and use them to turn turbines in a virtual hydropower dam.
This ‘giant battery station’ as they call it could generate 200 megawatts, sufficient for 400,000 homes.
This is an excellent example of recycling scarce resources and putting them to productive use. A number of German universities are working alongside to ensure the conversion begins promptly in 2018. We expect the project will save many jobs.
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A Step Closer to Reliable Renewable Solar Energy
Preview Image: Whitelee Wind Farm
