WO2008048239A2

WO2008048239A2 - Expandable hydrogen fueling station and method of supplying hydrogen therein

Info

Publication number: WO2008048239A2
Application number: PCT/US2006/036162
Authority: WO
Inventors: Michael S. Hsu
Original assignee: Ztek Corporation
Priority date: 2005-09-16
Filing date: 2006-09-18
Publication date: 2008-04-24
Also published as: WO2008048239A3

Abstract

A staged plan for constructing hydrogen supply stations is disclosed. The staged plan reduces the financial risk and enables the hydrogen supply stations to start operational quickly. The staged plan explores the technical flexibility permitting the staged construction of hydrogen stations, thus allowing incremental funding for initiating a functional station at small capacity with limited services and reaching a full capacity and full function as the industry matures in the future. The staged plan lowers the initial cost for stations and provides flexibility to schedule the expansion toward a full operation.

Description

EXPANDABLE HYDROGEN FUELING STATION AND METHOD OF SUPPLYING HYDROGEN THEREIN

Related Application

This application claims priority to U.S. Provisional Application No. 60/717,926 filed September 16, 2005.

Background of the Invention

Due to the continued depletion of the oil reserves, the price of gasoline has been volatile, and it appears that it may invariably follow an upward price trend over time.

Unlike oil, hydrogen can be produced through many industrial processes from abundant natural raw materials, including water. The price of the hydrogen may settle at a reasonable price level dictated by supply and demand. Therefore, the hydrogen industry can develop a long-term commercial strategy, unlike the oil industry, to finance its growth.

Although the demand of hydrogen infrastructure for transportation is increasing, building the infrastructure is cost intensive and hence awaits future technological innovations to reduce costs. Furthermore, the current financial plans in the industry only address the costs for full function stations and the required number of stations for a full- function fueling network. The current available planning model for the fueling networks also provides full function stations, and does not consider the potential of staged implementation for stations in this emerging industry.

Summary of the Invention

The present invention provides a staged plan for constructing hydrogen fueling stations to reduce the startup budget requirements and to have the stations in operation quickly. The present invention explores the technical flexibility permitting the staged construction of hydrogen supply stations, thus allowing incremental funding for initiating a functional hydrogen supply station at a small capacity with limited services and reaching a full capacity and function as the industry matures with time. The present invention lowers the initial cost for hydrogen fueling stations and provides flexibility to schedule the expansion toward a full operation.

The staged construction plan provides the geographical spread of the infrastructure program. The staged construction plan with a given budget provides, at the onset of building the infrastructure of hydrogen supply stations, a maximum number of hydrogen supply stations in a given territory to provide the mobility for the car owners. The present invention eliminates the concerns of excess capacity at given locations and the associated financial waste. The construction of subsequent stages can be timed according to the pace of rising demand, which eliminates waste of idle equipment waiting for more hydrogen vehicle to arrive in the neighborhood. The expansion of the hydrogen supply station may be carried out responsively with the actual rollout of the automobiles. The quality of services available at the hydrogen supply station will improve with time, while the cost of services can be maintained with technological advancement and the volume of sales.

Brief Description of the Drawings

The foregoing and other objects, features and advantages of the invention will be apparent from the following description and apparent from the accompanying drawings, in which like reference characters refer to the same parts throughout the different views. The drawings illustrate principles of the invention.

FIG. 1 is a schematic block diagram illustrating an exemplary stage of a hydrogen supply station in the illustrative embodiment of the present invention.

FIG. 2 is a schematic block diagram illustrating another exemplary stage of the hydrogen supply station in the illustrative embodiment of the present invention. FIG. 3 is a schematic block diagram illustrating another exemplary stage of the hydrogen supply station in the illustrative embodiment of the present invention.

FIG. 4 is a schematic block diagram illustrating another exemplary stage of the hydrogen supply station in the illustrative embodiment of the present invention.

FIG. 5 shows an exemplary hydrogen fueling infrastructure implementation plan in the illustrative embodiment of the present invention.

Description of Illustrated Embodiments

To realize a staged setup of a hydrogen supply station that meets economic criteria, the illustrative embodiment of the present invention utilizes a convertible compressor that is capable of the following functions and the combination of the functions. In the first configuration or function, the convertible compressor may be configured to compresses hydrogen from a low pressure around ambient pressure to around 2,000 psi to a medium pressure around 2,000 psi to around 4,000 psi. In the second configuration or function, the convertible compressor may be configured to compress hydrogen from a medium pressure around 2,000 psi to around 4,000 psi up to a high pressure around 4,000 psi to around 14,000 psi. In the third configuration or function, the convertible compressor may be configured to compress hydrogen from a low pressure around ambient pressure to around 2,000 psi to high pressure around 4,000 psi to around 14,000 psi.

In the illustrative embodiment, the high pressure hydrogen refers to hydrogen that has a useful level of an energy density for hydrogen powered vehicles or power plants. The high pressure hydrogen may be above the pressure at which natural gas is generally stored. For example, the high pressure hydrogen may have a pressure range of around 4,000 psi to around 14,000 psi in the illustrative embodiment. Preferably, the high pressure hydrogen may have a pressure range of around 5,000 psi to around 12,000 psi in the illustrative embodiment. Those of ordinary skill in the art will appreciate that the pressure range of high pressure hydrogen may differ in other embodiments depending on, for example, the high pressure hydrogen tank used for storing the high pressure hydrogen in the hydrogen powered vehicles or power plants.

In the illustrative embodiment, the low pressure hydrogen refers to hydrogen that is generated from a hydrogen generator described below with reference to FIGS. 3 and 4. The low pressure hydrogen is then compressed to high pressure hydrogen that can be used in hydrogen powered vehicles or power plants. For example, the low pressure hydrogen may have a pressure range of ambient pressure to around 2,000 psi in the illustrative embodiment. Preferably, the low pressure hydrogen may have a pressure range of around 50 psi to around 300 psi in the illustrative embodiment. Those of ordinary skill in the art will appreciate that the pressure range of low pressure hydrogen may differ in other embodiments depending on the hydrogen generator used for generating hydrogen.

In the illustrative embodiment, the medium pressure hydrogen refers to hydrogen that has hydrogen pressure between the high pressure hydrogen and low pressure ^N hydrogen described above. In particular, the medium hydrogen may have a pressure range of hydrogen that is suitable for delivering hydrogen from one station to another station. For example, the medium pressure hydrogen may have a pressure range of around 2,000 psi to around 4,000 psi in the illustrative embodiment. Those of ordinary skill in the art will appreciate that the pressure range of medium pressure hydrogen may differ in other embodiments.

The convertible compressor can be field reconfigured from a parallel-action operation, a split-action operation to a series-action operation. The parallel-action operation is a single stage compressor with two or multiple compressor heads working in parallel, which may be used for performing the compression in either the first configuration or the second configuration, as specified above. The series-action operation of two or multiple stages of compressor heads is capable of performing the full range compression, as specified above in the third configuration. A split-action operation of two or multiple compressor heads is capable of performing the full range compression, but allows storage elements of medium pressure to be installed between the compression stages, e.g. between the first function and the second function as specified above.

For example, a compressor from PDC Machines, Inc., Pennsylvania, USA, can be configured to offer the following multiple capabilities. The compressor may be configured to be capable of 2 scfm throughput in compressing the hydrogen from around 100 psi to around 3600 psi. The compressor may be configured to be capable of 70 scfm throughput in compressing the hydrogen from around 3600 psi to around 7000 psi. The compressor may be configured to be capable of 10 scfm throughput in compressing the hydrogen from around 100 psi to around 7000 psi.

The proper utilization of the convertible compressor to meet the multi-stage setup of the hydrogen supply station will be described below in more detail with reference to FIGS. 1-5.

FIG. l is a block diagram illustration the initial stage of a hydrogen supply station in the illustrative embodiment of the present invention. The initial stage of a hydrogen supply station 100 may include a low pressure storage element 110, a convertible compressor 120, and a dispenser 130. At the initial set-up stage, hydrogen of around 3600 psi may be provided to the station 100 from an industry gas supplier and stored in the low to medium pressure storage element 110. The low to medium pressure storage element generally refers to any storage device capable of storing hydrogen at around 4000 psi or lower pressure, and preferably around 2400 psi or around 3600 psi, which is common in the industrial gas trade. To provide the hydrogen as a transportation fuel for the vehicle 140, the compressor 120 performs the second function described above. At a filling rate of 70 scfm, it may take above 30 minutes to fully fuel a tank of 2100 cf or 5kg of hydrogen in the vehicle 140. The foregoing station can be implemented in a cost effective manner.

FIG. 2 is a schematic block diagram illustrating another stage of the hydrogen supply station according to the teachings of the present invention. This stage of the hydrogen supply station 200 may include a convertible compressor 210, a high pressure storage element 220, and a dispenser 230. The illustrative embodiment provides a high pressure storage element 220 of around 7000 psi to improve station performance. The high pressure storage element generally refers to storage devices capable of storing hydrogen at around 4000 psi or higher pressure, and preferably around 6250 psi or around 10,000 psi. The hydrogen provided to the station 200 at around 3600 psi will be compressed and stored in the high pressure storage element 220. Upon the arrival of customers, the hydrogen fueling can be accomplished with 4 minutes of time.

FIG. 3 is a schematic block diagram illustrating another stage of the hydrogen supply station according to the teachings of the present invention. This stage of the hydrogen supply station 300 may include a reformer 310, a convertible compressor 320, a high pressure storage element 330, and a dispenser 340. As the fueling activities of the station increases with time, a hydrogen generator, such as a reformer or an electrolyzer 310, would be a practical, efficient, cost effective way to reduce the cost of hydrogen provided to the station. An available hydrogen reformer 310 of 10 cfm from Ztek Corporation, Massachusetts, USA, may produce hydrogen at a rate of 36kg per day, which is sufficient to meet the needs of nine (9) passenger cars per day.

FIG. 4 is a schematic block diagram illustrating another stage of the hydrogen supply station in the illustrative embodiment of the present invention. The hydrogen supply station 400 may include a reformer 410, a convertible compressor 420, a high pressure storage element 430, and a dispenser 440. In this embodiment, the dispenser 440 is in communication with the vehicle when filling hydrogen. The dispenser control electronics will perform temperature compensated fueling to a full pressure. This includes control algorithm that may account for the heat of compression and achieve fast full fill less than 5 minutes for 4kg of hydrogen for passenger cars. If the dispenser 440 is not equipped with temperature sensors, nor controls capability, the filling time is longer than 6 minutes for 4kg of hydrogen for passenger cars.

With an unpredictable ramp-up rate of hydrogen automobiles on the road, the staged approach of the present invention provides two benefits: controlling capacity excess; and facilitating investment-timing decisions. One of ordinary skill in the art will appreciate that the above models can be implemented at any multiples depending on market intensity planned by the automotive industry. One of ordinary skill in the art will also appreciate that the above models are illustrative stages for constructing a hydrogen supply station and the hydrogen supply station can be constructed in a different sequence of the stages in different embodiments.

Applying the combination of staged and clustered implementation plan, a given budget for a single station can be augmented to support multiple stations. Alternatively, the project can be funded privately with government offering guaranteed hydrogen purchase plan based on the net of annual production deduct realized sales similar to the policies adopted in the utility and telecommunication industries. The surplus in the guaranteed purchase fund can be applied in the continued projects. The number of stations with a given government budget can be greatly multiplied.

FIG. 5 shows an exemplary hydrogen fueling infrastructure implementation plan in the illustrative embodiment of the present invention. This plan may start out with funding for equipment that will provide hydrogen fueling meeting the initial demand, and is annually upgraded incrementally to meet increased demand and realize a controlled operating cost. The station design will be based on a full capacity station including P&ID for the station, component specifications and vendor(s) list, electrical and civil design for site construction and equipment installation, definition of all permits and certification requirements (state, federal etc.), detailed cost estimate, etc.

The implementation may begin with no-frills site construction; for example, at an initial capacity of two cars per day, and thereafter proceed proactively to meet the actual needs based on the automakers annual forecast of introduction of fuel cell vehicles.

The staged implementation plan is best carried out in a cluster of stations where a lead station is a full function station equipped to produce low cost hydrogen, and a number of satellite stations only equipped with fueling equipment. Alternatively, the lead station and the satellite stations can be positioned along the stretches of roadways. The synergy is in the form that the lead station supplying hydrogen to the satellite stations and the latter serves as hydrogen sales outlets. This cluster pattern when implemented properly can offer an inherent outward reaching effect encouraging the mobility of vehicles, an inherent outward grow of the stations activities, minimizing the project cost and achieving the maximum hydrogen consumption, minimizing the hydrogen cost with a high station utilization, etc.

As the hydrogen demands increases with time, the satellite station can advance to equipment with hydrogen production equipment allowing the frontier of the cluster to move outward. This concerted effort for staged station construction can achieve a maximum number of stations for a given budget. The timing of growth is controlled by the real demands which prevent the waste of overbuild.

As the clusters plan establishes an economically minded operation, the private funding assisted by proper government grants can create a positive cash flow and grow in tune with the expansion of the clusters outwards and upwards.

It will thus be seen that the invention efficiently attains the objects set forth above, among those made apparent from the preceding description. Since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are to cover generic and specific features of the invention described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described the invention, what is claimed as new and desired to be secured by Letters Patent is:

Claims

What is claimed is:

1. A fueling station for providing hydrogen fuel for transportation in the form of compressed gas, the fueling station comprising: a medium pressure storage element for storing medium pressure hydrogen; a boost compressor for compressing the medium pressure hydrogen to high pressure hydrogen; and a dispenser for supplying the high pressure hydrogen to a vehicle.

2. The fueling station of Claim 1 , wherein the medium pressure storage element stores hydrogen of around 2,000 psi to around 4,000 psi.

3. The fueling station of Claim 1 , wherein the boost compressor compresses the medium pressure hydrogen to high pressure hydrogen of around 5,000 psi to around 12,000 psi.

4. The fueling station of Claim 1 , wherein the medium pressure storage element stores hydrogen obtained from sources outside the station.

5. The fueling station of Claim 1, wherein the medium pressure storage element stores hydrogen received from a hydrogen generator in the station.

6. The fueling station of Claim 1 , wherein the medium pressure storage element is detachable from the station.

7. The fueling station of Claim 1, wherein the medium-pressure storage element is connected with station equipment with quick connection-disconnection hardware for easy removal.

8. The fueling station of Claim 1 , wherein the station is included in a cluster of stations, in which the medium pressure storage elements is detached and attached for transporting hydrogen among the stations within the cluster.

9. The fueling station of Claim 1, wherein the station is included in a cluster of stations, in which the medium pressure storage elements is detached and attached for transporting hydrogen to and from other industrial locations for proper use.

10. The fueling station of Claim 1 , wherein the dispenser dispenses a mixture of hydrogen and natural gas for Alternative Fuel Vehicle (AFV)

11. The fueling station of Claim 1 , wherein the boost compressor is convertible to a high pressure compressor for compressing low pressure hydrogen to high pressure hydrogen.

12. The fueling station of Claim 11, wherein the boost compressor is configured to a parallel operation.

13. The fueling station of Claim 11, wherein the high-pressure compressor is reconfigured to a serial operation.

14. The fueling station of Claim 11 , wherein the high-pressure compressor is a multi- stage unit compressor

15. The fueling station of Claim 11 , wherein the boost compressor has a less compression ratio but more compression capacity than the high-pressure compressor.

16. The fueling station of Claim 11 , in which the high pressure compressor compresses hydrogen of around 50 psi to around 300 psi to hydrogen of around 5,000 psi to around 12,000 psi.

17. A fueling station for providing hydrogen fuel for transportation in the form of compressed gas, the station comprising: a high pressure compressor for compressing low pressure hydrogen to high pressure hydrogen; and a dispenser for supplying the high pressure hydrogen to a vehicle.

18. The fueling station of Claim 17, further comprising: a high pressure storage element for storing the high pressure hydrogen from the high pressure compressor; wherein the dispenser supplies the high pressure hydrogen from the high pressure storage element to the vehicle resulting in reduced fueling time.

19. The fueling station of Claim 17, further comprises: a hydrogen generator for generating the low pressure hydrogen and providing the low pressure hydrogen to the modified compressor for compression to high pressure for storage in high pressure storage, resulting in continued or increased supply of hydrogen for dispensing.

20. The fueling station of Claim 17, wherein the high pressure compressor is configured to a split-action operation: 1) compression of low pressure hydrogen to medium pressure hydrogen; 2) compression of medium pressure to high pressure hydrogen.

21. The fueling station of Claim 17, further comprising; a dispenser controller for enabling the dispenser to communicate with the vehicle when filling hydrogen, wherein the dispenser controller performs temperature compensated fueling to a full pressure.

22. The fueling station of Claim 17, wherein the high pressure compressor compresses hydrogen of around 50 psi to around 300 psi to hydrogen of around 5,000 psi to around 12,000 psi

23. A fueling station of Claim 17, in which the compressor is reconfigured to compress hydrogen of around 50 psi to around 300 psi to hydrogen of around 2000 psi to around 4000 psi.

24. A cluster of hydrogen stations comprising: a lead station that is capable of producing hydrogen by reforming of hydrocarbon fuels or by electrolysis of water, and one or more satellite stations that dispense hydrogen received from the lead station.

25. The cluster of hydrogen stations of Claim 24, in which the lead station produces hydrogen at a low pressure and compress the hydrogen to high pressure for dispensing to vehicles.

26. The cluster of hydrogen stations of Claim 24, in which the satellite station receives hydrogen at medium pressure and compresses the hydrogen to high pressure for dispensing to vehicles.

27. The cluster of hydrogen stations of Claim 24, in which the hydrogen of medium pressure is more suitable for transport than low pressure hydrogen which is bulky and than high pressure hydrogen which is relatively unsafe and needs heavy container to transport.

28. The cluster of hydrogen stations of Claim 24, in which the satellite station is expanded to become another lead station which in turn feeds additional and new satellite stations

29. The cluster of hydrogen stations of Claim 24, in which the satellite station comprises compressors to become a lead station, the compressors being modified through stages of operation such that a first stage of the compressors is capable of compressing hydrogen from medium press of around 2,000 psi to around 4,000 psi to high pressure of around 5,000 psi to around 12,000 psi and that a second stage of the compressors is capable of compressing hydrogen from low pressure of around 50 psi to around 300 psi to high pressure of around 5,000 psi to around 12,000 psi.

30. A method for providing hydrogen fuel in a fueling station, the method comprising: providing hydrogen fuel for transportation in the form of gas, liquid or hydride; and supplying the hydrogen fuel to customers at prices determined based on hydrogen quality and time consumed for supplying the hydrogen fuel to the customers.

31. The method of Claim 30, further comprising: supplying most valued hydrogen fuel when a service is available upon the customer's arrival with fueling completed in five minutes or less.

32. The method of Claim 30, further comprising: supplying moderately valued hydrogen fuel when a service is available upon the customer's arrival with fueling completed longer than five minutes.

33. The method of Claim 30, further comprising: supplying low valued hydrogen fuel when a transaction is conducted by appointment only with service completed in five minutes or less.

34. The method of Claim 30, further comprising: supplying lowest valued hydrogen fuel when a transaction is conducted by appointment only with service completed longer than five minutes.

35. The method of Claim 30, further comprising: supplying premium grade hydrogen fuel by delivery to a parked location of a vehicle.

36. The method of Claim 35, wherein the premium grade hydrogen fuel is produced using renewable feedstock and/or renewable energy.

37. The method of Claim 30, wherein hydrogen is purchased with a prepaid card based on a desired amount less than the expectancy of specific hydrogen consumption.

38. The method of Claim 30, wherein hydrogen is purchased with prepaid card at a guaranteed price and a desired hydrogen amount less than the consumption expectancy of a vehicle.