Apparatus to reduce the cost of renewable hydrogen fuel generation by electrolysis using combined solar and grid power

• US 20080236647A1
• Filed: 03/27/2007
• Published: 10/02/2008
• Est. Priority Date: 03/27/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Gibson, Thomas L., Kelly, Nelson A.
• Granted Patent: US 7,645,931 B2
• Time in Patent Office: Days
• US Class Current: 136/244
• CPC Class Codes: C25B 1/04 by electrolysis of water
• CPC Class Codes: C25B 15/00 Operating or servicing cells
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis

Abstract

One embodiment of the invention includes a PV array and an electrolyzer operatively connected together and each operatively connected to a utility power grid so that electricity produced by the PV array is selectively delivered to the utility power grid and the electrolyzer. The resulting process increases the efficiency of the solar-hydrogen production process, and results in lower-cost renewable hydrogen.

Claims

1. A product comprising:

a PV array and an electrolyzer operatively connected together and each operatively connected to a utility power grid so that electricity produced by the PV array is selectively delivered to the utility power grid and the electrolyzer.

2. A product as set forth in claim 1, wherein at least a portion of the electricity produced by the PV array is delivered to the utility power grid when at least a portion of the electricity from the PV array is not desired for the electrolyzer.

3. A product as set forth in claim 1, further comprising a controller to control electricity flow so that electricity is selectively delivered from at least one of the PV array or the utility power grid to the electrolyzer.

4. A product as set forth in claim 3, wherein the total electricity flow to the electrolyzer corresponds to an optimum operating current for the electrolyzer that is predetermined to minimize the cost of hydrogen production.

5. A product as set forth in claim 1, further comprising a variable DC AC inverter electrically connected to the PV array and the utility power grid.

6. A product as set forth in claim 1, further comprising an ammeter electrically connected to the electrolyzer.

7. A product as set forth in claim 1, further comprising a variable AC DC converter electrically connected to the utility grid and the ammeter.

8. A product as set forth in claim 1, further comprising a potentiometer electrically connected to the PV array and the ammeter.

9. A product as set forth in claim 1, further comprising a variable DC DC converter electrically connected to the PV array and the ammeter.

10. A product as set forth in claim 1, further comprising a switch between the PV array and at least one of the potentiometer or the variable DC DC converter.

11. A product comprising:

a PV array;

a variable DC AC inverter electrically connected to the PV array;

a utility power grid electrically connected to the variable DC AC inverter;

a variable AC DC converter electrically connected to the utility power grid;

at least one of a variable DC DC converter or a potentiometer electrically connected to the PV array;

an ammeter electrically connected to the variable AC DC converter and at least one of the variable DC DC converter or the potentiometer;

an electrolyzer connected to the ammeter; and

a controller constructed and arranged to control electricity flow to the electrolyzer from the PV array and the utility power grid.

12. A product as set forth in claim 11, wherein the variable DC DC converter and the potentiometer are connected to the PV array by a switch.

13. A process comprising:

selectively delivering electricity to an electrolyzer from a utility power grid and from a PV array.

14. A process as set forth in claim 13 wherein at least a portion of the electricity from the PV array is delivered to the utility power grid when at least a portion of the electricity from the PV array is not desired for the electrolyzer.

15. A process as set forth in claim 14 wherein the electricity is delivered to the utility power grid from the PV array using a variable DC AC inverter.

16. A process as set forth in claim 13 wherein the electricity is delivered to the electrolyzer from the PV array using at least one of a potentiometer or a variable DC DC converter.

17. A process as set forth in claim 13 further comprising converting electricity from the utility power grid to DC before delivering the electricity to the electrolyzer.

18. A process as set forth in claim 17 wherein the converting is accomplished using a variable AC DC converter.

19. A process as set forth in claim 13 further comprising controlling the total electricity flow to the electrolyzer using a controller comprising a mainframe computer or microprocessor and associated circuits, switches, and wiring.

20. A process as set forth in claim 19 wherein the total electricity flow to the electrolyzer corresponds to the optimum operating current for the electrolyzer.

21. A process as set forth in claim 14 wherein the total renewable electricity flow from the PV system to the utility grid corresponds to the amount of renewable electric energy required to operate the electrolyzer and to produce a desired amount of renewable hydrogen fuel.

22. A process as set forth in claim 19 wherein the transfer of renewable electricity flow between the PV system and the utility grid enables the PV-electrolyzer system to operate continuously, renewably, and sustainably while generating hydrogen fuel at a reduced cost per unit amount.