Gravity Batteries: any nation can do it at scale using rocks

Tesla worked on these in the early days as well. Just need some pyramids, with pyramidions, wired up properly IMHO to tap the Earth's natural charge fields:
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https://energypost.eu/gravity-batteries-any-nation-can-do-it-at-scale-using-rocks/

Gravity Batteries: any nation can do it at scale using rocks
July 27, 2022 by Simon Read


The beauty of gravity batteries is that they simply involve lifting (charging) and lowering (discharging) a heavy weight, explains Simon Read writing for the World Economic Forum. For pumped hydro, access to water and a geological height difference is needed. But if you’re using rocks or bricks, anyone can do it anywhere, and at any scale. The rest is just a construction job. No rare materials or minerals will ever be needed, nor chemicals that lose their potency over time. The gravity battery can last as long as any cement construction can be maintained, which is effectively forever. Read looks at lifted weights (or lowered into old mine shafts), pumped hydro, and a system where water is used to lift much heavier weights thus combining the two to achieve far greater gravitational potential. Makes you wonder why we’ll ever need lithium batteries or anything else for grid storage.

Engineers are developing huge ‘gravity batteries’ to store power from renewable energy generators.
Finding ways to store renewable energy is essential if the world is to move away from fossil fuels.

Some technologies use water as well as gravity to store power.

One company is planning to use former mine shafts to house the giant gravity batteries underground.
Engineers are in a race to answer one of the most urgent questions about our switch to renewable energy – how to store it? Electricity generated by wind and solar farms is not available when the sun isn’t shining or the wind isn’t blowing, so without ways of storing the power, anything not used immediately is wasted.

Gravity batteries might be the answer. The idea sounds simple – when there is plenty of green energy, the batteries use the power to lift a heavy weight either high into the air or to the top of a deep shaft. Then when the power is needed, winches gradually lower the weight, and produce electricity from the movement of the cables.

This would mean you could store power captured by a solar farm during the day when the sun is shining, and then release that electricity to the grid in the evening when demand rises because people are at home using electricity to watch TV, cook and heat their homes.

Gravitricity’s system lifts and then lowers heavy weights to store and generate power / IMAGE: Gravitricity
UK-based company Gravitricity has been testing a prototype gravity battery in the port of Leith, near Edinburgh. It is a 15-metre-high steel tower, which uses solar-powered motors to hoist two 25-tonne weights on steel cables. When the weights are lowered the motors become generators and release electricity.

Gravitricity’s senior test and simulation engineer Jill Macpherson told Raconteur the test had been a success: “The demonstrator was rated at 250kW – enough to sustain about 750 homes, albeit for a very short time. But it confirmed that we can deliver full power in less than a second, which is valuable to operators that need to balance the grid second by second. It can also deliver large amounts more slowly, so it’s very flexible”.

Gravity batteries vs Lithium-ion (or anything else!)
Gravity batteries are not the only way renewable energy can be stored; lithium-ion batteries dominate the market and some experts favour green hydrogen. But gravity is free, clean and easily accessible, without the complications of producing hydrogen or the environmental and human rights concerns linked to some lithium mining.

Although gravity batteries big enough to supply power grids are still some years away, the technology is evolving quickly. Oliver Schmidt, a clean energy consultant and visiting researcher at Imperial College London told Science.org that gravity-based storage has much to merit it. While lithium-ion batteries lose capacity after they’ve been charged and recharged over years, the gravity systems are made of robust components which will last much longer: “It’s mechanical engineering stuff… It’s relatively cheap,” he says.

Water-based gravity systems

Gravitricity is one of a number of companies trying to build on the concept of pumped hydro, which involves pumping water uphill when power is plentiful, and then letting it flow back down again later, turning the turbines in a hydroelectric generator.

Unlike gravity batteries, pumped hydro is an established technology that provides more than 90% of the world’s high-capacity energy storage, according to the International Hydropower Association. But facilities are expensive to build and restricted by geography: the technology requires hills and access to water.

Gravity Power, based in California, USA and the German company New Energy Let’s Go have adapted the idea of combining water and gravity to store power. Both companies have systems in which water is forced through a turbine by a large, piston-shaped rock housed in underground shafts.

Watch the short video here / SOURCE: Gravity Power


Storing power in mineshafts

Gravitricity’s system doesn’t use water, but the company’s engineers are also planning to use underground shafts rather than towers for full-scale versions of its gravity batteries, which will require much heavier weights than the Leith prototype. The team is currently investigating if they can use disused mine shafts in the Czech Republic, Poland and South Africa. Gravitricity plans to launch its first full scale system in 2023/24.

The firm’s Managing Director, Charlie Blair, says it is good to see former mining areas playing a part in helping to supply renewable energy: “Full-scale energy stores in former mines can make good use of existing infrastructure and create jobs in exactly those areas where they’re most needed… The emotional aspect of this is also important. Whole communities once worked in the mines – and generally they’re very happy to see them being used for storing renewable energy.”

The World Economic Forum founded the Global Battery Alliance (GBA) in 2017 to establish a sustainable battery supply chain by 2030. The body of over 100 leading international organisations, NGOs, industry actors, academics and multiple governments became independent in 2021 and its membership is collectively working towards the goals set out in the GBA 2030 Vision.

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Simon Read is a Senior Writer at Formative Content, writing for the World Economic Forum

This article is republished in accordance with the Creative Commons Attribution-Non Commercial-No Derivatives 4.0 International Public License

Apparently there is a German company doing this with a product. Gut feeling applying Miles a bit with the charge field fully enabled could create a revolution of sorts with this tech:

https://heindl-energy.com/about-us/
https://heindl-energy.com/technical-concept/engineering-challenges/

study by Imperial College
https://docs.wixstatic.com/ugd/496e1f_3b3097d4fc7f4df985c975224fc101b3.pdf

Status of Development & Next Steps

The concept of Gravity Storage was invented by Professor Eduard Heindl and has since 2014 been continually developed by the company Heindl Energy GmbH, supported by a team of civil engineering, geology, mining and geophysics specialists.

Heindl Energy GmbH has been sold in 2021 to New Energy Let´s Go UG, based in hamburg (Germany) and being a SPV funded by Dr. Sven Bode as an interim investor who is restructuring the assets and is now looking worldwide for a new strategic investor willing to continue the development with the goal of constructing a pilot project to verify the concept. Such a demonstrator will be the starting point of a stepwise market uptake and a gradual commerzialisation.

Many institutions and cooperating partners have been involved in developing Gravity Storage so far. To build the demonstration plant we have all necessary services, engineers, and consultants on hand. A close network of scientific institutions may ramp up its activities on this technology. Eduard Heindl and his team are looking forward to providing full support for a breakthrough of this large-scale gravity-based storage technology.

For providing new funds we cooperate with Alexander Gärtner at the agency GARDNER CONSULTING based in Munich.

Don´t hesitate to get in touch: info@heindl-energy.com

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Geology
Gravity Storage requires suitable geological conditions but no elevation difference.


Gravity Storage plants should be located in areas with solid bedrock. The most favorable sites have stable, little-faulted rock such as granite or compact layers of otherwise solid rock material. The geological conditions must first be assessed in detail by a team of geologists. Heindl Energy provides all services required to evaluate potential sites.

In order to estimate how widespread suitable geological conditions for Gravity Storage might be, Heindl Energy has conducted a study analyzing different types of magmatic, metamorphic and sedimentary rock. A total of 117 globally distributed sites where analyzed, and a classification performed based on the internationally recognized Rock Mass Rating (RMR) system. The suitability of the geological conditions for construction of a Gravity Storage plant was found to be “very good” (RMR I) at 3% of the evaluated sites, and “good” (RMR II) at 43%. The remaining sites would require extensive, expensive rock stabilization measures, or would be suitable only for a relatively small Gravity Storage plant.

Geological suitability of evaluated sites for construction of a Gravity Storage plant (corresponding number of sites in brackets).