Archive for the ‘Energy Storage Patents’ category

Optimizing Green Patent Protection: A Study in Energy Storage Service

December 3rd, 2013

 

Stem is a Millbrae, California, startup that sells and leases its battery energy storage system, which is marketed as a way to reduce consumers’ energy bills.  Specifically, the company makes a lithium-ion battery connected to analytics software that determines the best times to draw energy from the battery, thereby reducing electricity demand charges.

As more demand side energy efficiency / smart grid technologies are being offered as services (with leasing of equipment rather than sale), I’ve been thinking about what this might mean for green patent drafting.  One of the things patent prosecutors consider when preparing a patent application is how to draft the claims to ensnare as many different potential infringers in the chain of commerce as possible.

On this score, it is important to keep in mind the acts that can constitute infringement, viz., making, using, selling, offering for sale, and importing into the United States.

In conventional scenarios, the competitors that could be infringers are typically manufacturers that make, offer for sale, and sell competing products as well as the end users of the products.  There could be distributors in the chain too, but these may or may not be viable infringement targets because of the patent exhaustion doctrine, which holds that an unrestricted authorized sale of a patented product “exhausts” the patent holder’s rights to control the use and sale of the product.

Taking Stem’s battery energy storage as a service as an example, the company owns at least one U.S. patent and one pending patent application relating to its technology.  Both are entitled “High speed feedback adjustment of power charge / discharge from an energy storage system” and are Publication No. 2013/0207591 (’591 Application), which is a continuation of U.S. Patent No. 8,350,521 (’521 Patent).

Generally speaking, the ’521 Patent and ’591 Application are directed to smart charge systems and power management methods in which power demand load data and variable generator power data are synchronized in time and used to provide optimal charge/discharge instructions to an energy storage unit.

The simplest infringement scenario, of course, would be competing manufacturers that make and sell products that infringe the ’521 Patent by their manufacturing and sales activities; there also could be end users who infringe by their use.  But what about a competitor that simply leases infringing systems to end users? 

This hypothetical competitor has situated itself at a spot in the commercial chain where it may be able to avoid a charge of direct infringement because it is not making, selling, offering for sale, or importing an infringing product.  Depending on how the claims of the relevant patent are written, this competitor may not be using the product either.  It’s conceivable that the end users may be the only direct infringers in this scenario.

However, the patentee may have a case for inducing infringement against a competing storage as a service lessor if the patent claims are drafted carefully.  Section 271(b) of the patent statute provides that anyone who “actively induces” infringement of a patent is an infringer.  This means that someone who himself does not infringe, but induces another to do so (e.g., by providing a product with advertising or instructions about an infringing use), may be held liable for inducement, a form of secondary liability for patent infringement.

The ’521 Patent (and the ’591 Application) contains both system and method claims:  claims directed to a smart charge system and claims directed to a method of power monitoring and management.  Independent claim 1 of the ’521 patent is directed to a smart charge system including a premise sensor for measuring premise power information, a variable generator sensor for measuring generator power information, an energy storage unit, and a control computer that receives synchronized information from the sensors and energy storage unit and provides charge/discharge instructions.

It’s possible that an end user of the smart charge system might, through use of the system, be a direct infringer of claim 1 of the ’521 Patent and the company leasing the system could be liable for inducing the infringement of the end user.

A better candidate for inducement is independent claim 10 of the ’521 Patent because this is a method claim:

10. A method of power monitoring and management comprising:

providing, at a controller, a desired limit load;

receiving, at the controller, power demand load information;

receiving, at the controller, variable generator power information; and

transmitting, from the controller to an energy storage unit, a charge/discharge instruction based on the desired limit load, the power demand load information, and the variable generator power information.

Even if the end user isn’t using the whole system with all the components recited in claim 1, or if a different system is being used, the storage as a service lessor could still be liable for inducing infringement if it directs or instructs the end user to carry out the method steps recited in independent claim 10.

Having method claims in a patent provides better protection and greater flexibility for enforcement by exposing more players and activities in the commercial chain to potential infringement liability.  As clean tech companies continue to explore new business models, careful green patent claim drafting will become more important to ensure optimal protection.

 

 

Softbank, Bloom Boxes, and Green Patenting in Japan

August 19th, 2013

Softbank, a Japanese telecommunications and internet company, recently formed a joint venture with U.S. fuel cell maker Bloom Energy to sell electricity from Bloom’s natural gas fuel cells in Japan.

A theme of this Greentech Media article about the JV is that Japan is “energy-poor” after the almost complete shutdown of its nuclear energy program.  SoftBank believes Bloom’s fuel cells are a perfect fit for the country.

The article quotes the companies’ press release, which notes “a significant electrical power deficit in Japan” and a recent increase in energy imports to Japan.  The article also observes that the country’s solar industry is trying to fill the gap.

All of this got me thinking about patenting green technologies in Japan. 

Initially, I was curious whether Bloom owns any Japanese patents for its fuel cell technology.  The Greentech Media article says the JV with SoftBank is Bloom’s “first foray” into international markets.

Indeed, a search of a couple of international patent databases does not turn up any Japanese patents or published applications in the name of Bloom Energy.  Bloom does own a number of international, or PCT, patent applications, which, depending on their priority dates, may still be eligible for filing in Japan.

But filing a patent application in Japan is expensive.  Unlike the U.S. Patent and Trademark Office (USPTO), the Japan Patent Office (JPO) does not allow any free claims; it charges for each claim.  In addition, translation costs can be very high for technical documents such as patent applications. 

Factor in the cost of retaining a Japanese law firm for prosecuting the application, translating and responding to office actions, etc., and the total cost of obtaining a Japanese patent can set you back $15-20K or more.

JPO does have a green technology fast track program should you wish to expedite examination of your patent application.  However, the program is fairly burdensome.

To be admitted to the program the applicant must (1) submit a brief description of the invention explaining that the claimed invention reduces energy consumption or carbon dioxide emissions, and (2) conduct a prior art search, disclose the prior art, and submit an explanation comparing the invention to the prior art.

The search and explanation requirement shifts what would typically be the JPO patent examiner’s burden to the applicant.  Thus, the applicant has to pay its patent attorney to do substantial additional work, increasing the cost of the patent application.

Moreover, the comparative prior art explanation submission is analogous to the Examination Support Document (ESD) required for the USPTO’s Petition to Make Special for ordinary expedited examination.

In addition to the added expense, the ESD has been dubbed the “Express Suicide Document” because of the heightened risk of inequitable conduct applicants face based on the representations made in the ESD.  The comparative prior art explanation submission for the JPO green patent fast track program could expose the applicant to similar risks.

While Bloom is getting in, it and other green tech patent applicants face a costly and perhaps difficult process to obtain patents in Japan.

 

Patent Pending Velkess Flywheel with Gimbal Remains Resonantly Undisturbed

April 29th, 2013

A previous post reported on the acquisition of Beacon Power, formerly the largest flywheel player, after the company went bankrupt.

One of the technical hurdles faced by designers of these whirling rotational energy storage devices is that spinning masses have a natural “wobble.”  Most flywheel designers have employed expensive bearings, magnets, and materials in attempts to minimize this wobble to better align the flywheel’s axis of rotation with the rotation of a generator.

Enter Velkess, a Silicon Valley developer of new flywheel technology, which has invented a self-stabilizing design.  Velkess owns U.S. Patent Application Publication No. 2012/0096984, entitled “Flywheel system” (’984 Application).

The ’984 Application is directed to a flywheel system in which the wheel is suspended in a non-symmetric damped gimbal system (9) (a gimbal is a pivoted support that allows the rotation of an object about a single axis, commonly used in gyroscopes).  The shaft of a motor/generator (20) is attached to a flexible coupling (13), which is also attached to a rigid shaft (14).

 The rigid shaft (14) is attached at its other end to a super-circular bare filament flywheel rotor (16).  The shaft (14) can transmit high levels of torque and will not suffer the destabilizing displacement common in traditional flywheels.

According to the ’984 Application, the invention allows one axis of the gimbal to dampen the resonant frequencies in the other axis:

[T]he non-symmetric damped gimbal system 9 of embodiment 15 has two different resonant base frequencies established by the differing lengths of the pendulum that each axis 10 and 11 create. This allows one axis 10 or 11 of the non-symmetric gimbal 9 to damp the resonant frequencies in the other axis 10 or 11.

As explained nicely by Chris Nelder in a recent Scientfic American piece, this feature minimizes resonant disturbances and permits more control of the device:

The gimbal in the Velkess is asymmetrical, so the two axes of rotation—the flywheel axis as well as that of the rotor, which drives the brushless, inducting DC motor—are not on the same plane, and have different periods of frequency. This dampens the resonance effects that make traditional flywheels hard to control (a resonant disturbance in one of the planes can intensify until the device shatters). With the gimbal, resonance in one plane is translated into the other, which is nonresonant at the same frequency. Accordingly, only very loose engineering tolerances—about one sixteenth of an inch—are required to build the device.

According to Nelder, the Velkess flywheel has significant advantages over previous devices like those made by Beacon Power, including slower, longer discharge of stored energy, and scalability.  More info on the Velkess technology can be found on the company’s technology page.

Storage in the Mist: LightSail’s Patented CAES Tech

December 7th, 2012

 

LightSail Energy (LightSail) is a Berkeley, California, company that has developed compressed air energy storage technology which may be used for grid-scale storage. 

The company’s central innovation is the injection of a mist of water spray into a compressed air system so the spray rapidly absorbs the heat energy of compression and provides the energy during expansion.

According to Cleantech PatentEdge™, LightSail owns at least 52 US, international, and European patents and published applications.  U.S. Patent No. 8,240,142 (’142 Patent) is one of a family of patents relating to the company’s compressed air energy storage system.

The ’142 Patent is entitled “Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange” and directed to a compressed air energy storage system (20) including a cylinder device (21) defining a chamber (22), a piston device (23) in the chamber, and a pressure cell (25).  The cylinder (21) and pressure cell (25) together form a one stage reversible pressure compression/expansion mechanism (24).

Air enters the system (20) via pipe (10), passes through a filter (26) and enters the cylinder chamber (22) via pipe (30) where it is compressed by the action of the piston (23).  Before compression begins, a liquid mist is introduced into the chamber (22) using an atomizing nozzle (44).  The volume of mist injected into the chamber (22) is predetermined to be the volume required to absorb all the heat generated during that piston stroke.

As the mist condenses, it collects as a body of liquid (49e) in the cylinder chamber (22).  The compressed air/liquid mixture is then transferred into the pressure cell (25) through outlet nozzle (11) via pipe (51). 

According to the ’142 Patent, that is when the critical heat exchange occurs, followed by storage of the air:

In the pressure cell 25, the transferred mixture exchanges the captured heat generated by compression to a body of liquid (49f) contained in the cell.  The air bubbles up through the liquid and on to the top of the pressure cell, and then proceeds to the air storage tank 32, via pipe 33.

According to this Greentech Media piece, LightSail’s system is more efficient because it captures and stores both the mechanical energy and the thermal energy used in compressing air.  The article reports the company has received a recent funding round by some big name investors, including Bill Gates and Khosla Ventures.

Isentropic’s Pumped Heat Electricity Storage Runs Hot and Cold

June 28th, 2012

Isentropic is a UK company that has developed an energy storage system called Pumped Heat Electricity Storage (PHES).

Isentropic owns several international and U.S. patents and applications.  U.S. Application Publication No. 2010/0257862 (’862 Application) describes and claims the PHES technology.

Entitled “Energy storage,” the ’862 Application is directed to an energy storage system (10) comprising compressor/expander means (20) including a compressor (21), an expander (22), and power input/output means (40).

The energy storage system (10) also includes a first heat storage means (50), a second heat storage means (60), high pressure transfer means (70, 71) and low pressure transfer means (80, 81).

To charge the system (10), a low pressure gas enters the compressor (21) through inlet (23) and passes into a compression chamber (24).  The low pressure gas is compressed by a compression piston (25) and transferred via the high pressure transfer means (70) to the first heat storage means (50) where it transfers thermal energy to the first thermal store (53).

The gas then passes through the high pressure transfer means (71) and enters the expander (22) through inlet (27).  The gas is then expanded in the expansion chamber (28) and is transferred by the low pressure transfer means (81) to the second heat storage means (60) where it receives thermal energy from the second thermal store (63).

Finally, the gas passes through the low pressure transfer means (80) and can start the process again by entering the compressor (21).

According to Isentropic’s PHES technology web page, each heat storage means contains mineral particulates as a storage medium to interact with the pumped gas.

The company says the PHES system provides very high (72-80%) round trip efficiency comparable with pumped hydro, high reversibility, i.e., the system can function as both an engine and a heat pump, and no geographical restraints.

Isentropic should be able to showcase all of these advantages soon.  This GTM piece reports that a UK public-private partnership called the Energy Technologies Institute is investing $22 million to build a full-scale PHES demo system.