Environment

Velkess flywheel technology promises cleaner, more efficient energy storage

View 6 Images
Bill Gray is looking to the past to reinvent the future of energy storage with a new take on the spinning flywheel
Velkess desktop demonstration unit
Gray’s “soft” rotor is made of E-glass
Bill Gray is looking to the past to reinvent the future of energy storage with a new take on the spinning flywheel
The existing prototype flywheel floats on a high efficiency magnetic bearing assembly, can make or absorb 2 kW of power, and can store 0.5 kWh of energy
The Velkess flywheel floats on a high efficiency magnetic bearing assembly
View gallery - 6 images

It's no secret that the successful future of wind, solar and other renewable sources hinges on the development of cost effective energy storage systems.

Of the technologies currently in play, batteries are still expensive and limited in capacity, compressed air energy storage requires very specific spatial geological formations, thermal storage – often used in concentrated solar power (CSP) facilities – is also expensive and difficult to scale, and pumped storage hydroelectricity, while relatively inexpensive and efficient (70–85 percent), also requires specific geographical locations.

New approaches such as the ability to store energy in molecular bonds are also in development, but entrepreneur and inventor Bill Gray is looking to the past to reinvent the future of energy storage with a new take on the spinning flywheel.

Perhaps the most straightforward storage method of them all, energy storage flywheels have been in use for over a century. A flywheel is usually a heavy shaft-mounted rotating disc that absorbs and stores twisting or spinning motion and then releases it as rotational kinetic energy.

Armed with the pioneering research of John Vance, a retired professor at Texas A&M University (TAMU), Gray has developed a novel approach to flywheel design with a patent pending flywheel system called Velkess – short for VEry Large Kinetic Energy Storage System. According to Gray, Velkess is a radical improvement on existing flywheel technologies and is dramatically less expensive than even the most economical energy storage technologies available today.

Most existing flywheels are designed and built like the turbines of high performance jet engines. They use materials like carbon fiber composites and precision engineering to exactly control the forces inherent in all spinning rotors. These materials and the required engineering and control methods are extremely costly and not conducive to a low cost energy storage solution.

Gray’s “soft” rotor on the other hand is made of E-glass, operates in a vacuum and flexes in response to destabilizing forces therefore reducing the amount of stored power lost to friction down to about 2 percent on a daily basis. E-Glass or electrical grade glass (used in the reinforcing phase of fiberglass) is not as strong as carbon fiber but can store up to 20 times more energy per dollar. Like a cowboy’s lasso, it gains stability as it rotates and according to the company, the energy on the rotor can be held in complete safety even in the event of power failure or natural disasters like earthquakes.

Velkess desktop demonstration unit

The existing prototype flywheel floats on a high efficiency magnetic bearing assembly, can make or absorb 2 kW of power, and can store 0.5 kWh of energy. Gray needs to scale that storage capacity up 30 times to 15 kWh. That requires replacing the 25 lb flywheel rotor seen in the video with a 750 lb version.

“Our challenge is with the magnetic assembly," says Gray. "The magnets to float 25 lbs are easy to get on the internet and easy to work with by hand. Magnets strong enough to float 750 lbs, are a different story. They need to be custom made and are too powerful to safely work by hand.”

Gray has successfully raised funds on Kickstarter for the next phase of development which will fund the construction of a magnetic bearing and motor assembly. This is the final piece of the puzzle for the completion of a fully working prototype which would pave the way for demo units which will be used to market the invention to potential buyers.

More technical information about the Velkess flexible flywheel can be found in the Patent Application.

Sources: Velkess, Kickstarter

View gallery - 6 images
  • Facebook
  • Twitter
  • Flipboard
  • LinkedIn
29 comments
Alastair Carnegie
Maybe Bill Gray should drop the idea of fancy magnets? Make the bearing large! and use regular though high performance magnets. Adding active weight is hardly a disadvantage after all. The magnetic bearings could also double up as three-phase motor-generator. AC-DC-AC conversion by MOSFET units, similar to those used on railway trains. There is no need for laminated iron cores, as 'crenellated' coreless copper windings could do the job. The 'up' wire has N/S magnetic polarity, reinforced by the 'down' wire S/N polarity. Current induced by Flemming's right hand rule for motors. (and vica-versa for Magneto-Alternator)
The 'crenelated' windings would need to be on two levels, and phase staggered. Both continuous stator rings would support the load. The two rotor rings would need equal spaced gaps. |_| |_| |_| |_| etc. The lower ring magnets equally spaced where the gaps were located in the upper rings.
Graham
Allowing the flywheel to find an axis somewhat independent of the disturbances (like a washing machine drum) still does not get over the fact large amounts of energy are stored in the moving mass.
The upper limits of flywheel storage are found with one that is specially profiled so that the stress is the same everywhere, and breakup is near the point bits of the periphery are about to break away.
Also. extracting significant torque off that long thin shaft gives a classic buckle stress. If this gets loose, it had better be in the ground somewhere!
Ronald Leard
Off the shelf parts, with a horizonal shaft , enclosed bearing boats. ease of placement. extreem weights. Lower cost, larger weights, easy built on site of concreat wheels. Using off the shelf automotive torque converters. KISS is the way to go.
Paul Pierce
Some efficiency might be gained if it is operated in a vacuum to remove air drag resistance.
doug9694
Why have a wimpy spindle as output? Use coils and take electrical energy off, same as is added. Also use wind energy to add additional energy electrically or direct.
attoman
Reviewing the patent application one is challenged to see any significant improvement over existing art.
There are obvious ways to overcome the magnet and suspension problem based on the unique characteristics of an electrical energy storage system. Properties Gray fails to recount and utilize in his application.
The answer is there Bill keep looking. Good luck in the hunt.
wle
it;s a good idea to have the equivalent of 41 lbs of gunpowder outside your house??
wle
billybob1851
maybe Alastair should patent his idea...
JBar
How is my "net-metering" not energy storage. When my 5 kw (peak) solar array generates more than my unoccupied house is consuming, my electric meter tracks the excess and credits the power that was pushed back into the grid. What Bill Gates is really trying to accomplish here is renewable energy off the grid. Why spend money on redundant infrastructure...just run a powerline to your cabin and you have your energy storage. Surely Bill can find better things to spend his money on...say...developing an intuitive and easy to use operating system??
M.Digga
JBar, it's not everywhere that you can sell the energy back to the grid, you know?