Gravity Storage

About us

A new StoreAge

Who we are and what we do

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

Gravity Storage Inc. is the only shareholder of Heindl Energy. Gravity Storage Inc. is owned by Swiss investor HTG Ventures AG, which is financing the development of the concept. Gravity Storage Group holds several patents on this storage concept and is currently developing its readiness for realization, with the goal of constructing a pilot project.

The Team

Vice-Chairman of the Board, Gravity Storage Inc.

The hydraulic rock storage idea was conceived by
Professor Dr. rer. nat. Eduard Heindl, scientist, inventor, and entrepreneur.

After studying engineering (Dipl. Ing. FH) and physics (Dipl. Phys.), Prof. Heindl was a faculty member in the Physics Department at the University in Tübingen, concentrating on electron holography and neural networks.

In the summer of 1995, together with Andreas Benez, he founded Tübingen’s first Internet company.  In 1997 he started the SolarServer Internet platform with the vision that both Internet use and solar energy would grow exponentially, and therefore be successful. Both of these goals have been realized. On average, there are 10,000 visitors per day to the SolarServer site.

After professional positions at Integrata AG and the former Emprise AG, Eduard Heindl started a successful independent engineering company. This has become the current Heindl Internet AG, of which he is a member of the Supervisory Board. During a professorship at the Nürtingen-Geislingen University of Applied Science in 2001-2003 he returned to academia, and since 2003 has been a professor for e-business at the Furtwangen University. He is the author of several books foremost of which is his definitive work “The Webmaster”, for which he is known to many people interested in the Internet.

Creativity has always been his passion. In 2007 he was awarded the Wolfgang Heilmann Prize for his longstanding work regarding questions for structuring humane IT. He also developed the first Tsunami Alarm System, for which his A3M company, founded for this system, was awarded the ICT Prize of the European Union in 2007 for the best IT innovation.

Recently he has been increasingly occupied with issues involved with energy. He conceived of the hydraulic rock storage in 2010 in response to the realization that security of energy supply with a large share of renewable generation is not feasible without large storage capacities, which are so far lacking. In 2011 his concept was awarded the QUERDENKER-Award in Munich.

Eduard Heindl and his family reside on a farm in Furtwangen in the Black Forest, Germany.

As CEO of Gravity Storage Inc. and Managing Director of the Heindl Energy GmbH, Robert is in charge of General Management, financial management and political affairs. He was CEO in the green innovative energy business for more than 10 years. He knows the power market as well as the business of planning, constructing and funding wind, hydro, and solar power plants.

Robert has been active in public discussions on national and European energy policy for almost 20 years. In addition to his experience with the media, he draws on his extensive network in politics, business, and industry associations. He is one of the founders of the Hamburg Institute, a strategy consulting firm specialized on energy markets and policies.

Chairman Gravity Storage Inc.

Marc, Chairman of the Board of Gravity Storage Inc., has studied law at the universities of Frankfurt, Saarbrücken and Metz/France, and was admitted to the practice of law at the Bar of the State of New York. He has held senior management positions – mostly in finance functions and at board level – in the US, Germany, Switzerland and other countries for more than 30 years. Currently, he serves as the CEO of HTG Ventures AG, a swiss venture capital investor, which is major shareholder of Gravity Storage Inc., a position he holds since 2016. Further, he is member of the Board of several other companies. Prior to joining HTG Ventures, he advised companies in litigation management for national and international legal disputes, various structured finance and business development projects in renewable energies, and various mergers & acquisitions and structured financing projects. As a CFO he joined Armacell Inernational Holding GmbH from 2007-2011 and AgfaPhoto GmbH between 2004-2005. Marc served in the Lufthansa Group 1989-2001 as CFO of LSG Luft­hansa Service Holding AG, as Senior Vice President Corporate Group Finance of Deutsche Lufthansa AG, and Managing Director of Lufthansa Leasing GmbH. He also spent some time in banking at the Manufacturers Hanover Trust Company.

as a highly experienced construction engineer, he works on the design how to construct the Gravity Storage. He also developed the sealing system.



We are hiring!
Our Chicago-based team is looking for:

– Senior and Junior Engineers with a proven track record in Subsurface Sciences
   (e.g. Geology, Geotechnical Science, Mining, Tunnel Construction)
– Engineers in planning and construction
– Research Managers
– International Project Managers

Candidates should fully support the idea of renewables and energy storage and have experience working in small, global and innovative teams. All positions require exceptional intercultural competence and the willingness to travel globally.
Let´s get in touch!

Please contact Robert Werner, CEO, at

Status of development

We are preparing the engineering and planning for a demonstrator plant we intend to build to proof the concept. The demonstrator will be the starting point of a stepwise market uptake and a gradual commercialization.

Cooperations & Partners


Heindl Energy GmbH is member of the German American Chamber of Commerce (GACC) in New York. Gravity Storage Inc. is member of the GACC Midwest in Chicago.

contact info


Chicago office +1 312-561-9790
Stuttgart office: +49 711 6569689-0

Email Address

Main Office Adress

Am Wallgraben 99
70565 Stuttgart

Office USA

Gravity Storage Inc.
U.S. Representation
321 North Clark Street, Suite 1425
Chicago Illlinois 60654-4714
Phone:+1 312-561-9790
Fax:+1 312-644-0738

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