Currently showing: Sustainable energy

05 Dec 13 22:11

Electric power grids have always been a delicate balancing act between demand and supply. The massive arrival of fluctuating solar and wind renewable power into the grid has added to the complexity.

HHS is a massively scalable novel technology poised to solve the storage and balancing issue cheaply once and for all. "Hydraulic Hydro Storage", or "Lageenergiespeicher" is a surprisingly simple approach based on old and tested technology combined in a surprising fashion.

Where classic pumped hydro storage relied on tall mountains and tall lakes, which cost a fortune to install, and was always in the face of environmental concerns, the HHS does away with those issues and radically solves them.

The HHS, in fact, is not pumping water itself, but is using water as a hydraulic fluid to push up a very large cylinder of rock, sawn out of the ground anywhere on the continent where power grids need balancing, and where the rock underground is solid enough to allow for stable cylinders of about a hundred by fifty meters.

Since rock is 4 times more dense than water, a much higher energy content is achievable. And since cutting rock is also very cheap, the construction costs and complexities are small. Even better, the cost per stored kWh drops dramatically as the radius r of the cylinder increases:

Whereas the stored energy increases by r^4, construction costs only increase by r^2, so storage costs decrease by r^2.

The attached links show a plethora of data and presentations on the technology. A cost-comparison with current technology, showing a 10x-100x cost reduction, can be found under

The only engineering issue left at this point are the successive rings of seals placed around the middle of the cylinder. Their detailed design and testing is under way at this point.

Several pilot locations for the first HHS have been identified and are under examination in Southern Germany. I expect that as soon as the first pilot installation has been successfully running for two years, we will see many more of these friendly rocks coming out of the ground all around the world.

Nick Schaefer, CEO, XNRG GmbH,

Lageenergiespeicher: Strom aus Windkraftwerken und Solaranlagen speichern

Der Lageenergiespeicher kann mehrere 1000 GWh Strom in einem Felsen speichern.

Category: Sustainable energy

Location: Global


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