Technical Field

[0001 ] The present invention relates broadly to a solar-powered water electrolyser and relates particularly, although not exclusively, to a printed solar photovoltaic (PV) source directly coupled to an anion exchange membrane (AEM) electrolyser. The invention also relates generally to a method of constructing a solar-powered water electrolyser. The invention is also broadly directed to a printed solar PV source configured to power a water electrolyser.

Background

[0002] It is known to split or decompose water by electrolysis to provide oxygen and hydrogen. This decomposition of water can be effected within an electrolyser having electrodes/membranes and an associated DC power source. The associated DC power source may be provided by fossil-fuel or renewable energy sources such as conventional silicon-based solar panels. When the electrolyser is powered by solar panels, other balance of plant equipment is required to deal with the intermittent nature of the power supply. In particular, the solar powered electrolyser system requires a DC to DC converter for regulating voltages from solar panels to operational voltages required by the associated electrolyser. Furthermore, the system requires a maximum power point tracker (MPPT) to regulate the DC power from the solar panels whereby it remains within the operating power requirements of the water electrolyser.

Summary of Invention

[0003] According to a first aspect of the present invention there is provided a solar-powered water electrolyser comprising:

a water electrolyser adapted to receive water and being effective in electrolysis of said water to produce hydrogen;

a printed solar photovoltaic (PV) source directly coupled to the water electrolyser to power it for the production of said hydrogen. [0004] Preferably the printed PV source is configured to provide direct current (DC) power at a voltage at least substantially equal to an operating voltage of the water electrolyser. More preferably the printed PV source is configured to provide DC power having a current less than or substantially equal to an operating current of said electrolyser. Even more preferably the DC power provided by the printed PV source is supplied directly to the water electrolyser without regulation of the voltage and/or the current, or maximum power point tracking (MPPT).

[0005] Preferably the printed PV source includes a plurality of PV cells printed on a supporting substrate. More preferably the supporting substrate includes a flexible membrane to which the PV cells are directly printed. Still more preferably the supporting substrate includes a rigid support panel to which the flexible membrane and the associated printed PV cells are applied. Alternatively the PV cells are directly printed on a rigid support panel.

[0006] According to a second aspect of the invention there is provided a printed solar photovoltaic (PV) source comprising:

a supporting substrate;

one or more PV cells printed directly on the supporting substrate, said PV cells configured to provide power at a voltage at least substantially equal to an operating voltage of a water electrolyser to which the printed PV source is directly coupled for electrolysis of water to produce hydrogen.

[0007] Preferably the printed PV cells are printed in a predetermined pattern wherein the power provided is direct current (DC), at operating solar irradiances, substantially matching or within operating power requirements of the water electrolyser. More preferably the printed PV cells are electrically connected in a predetermined series and/or parallel configuration to provide the substantially matching power requirements of said electrolyser.

[0008] Preferably the printed PV source includes a plurality of electrical off-take points at predetermined locations on the PV cells to provide the substantially matching voltage requirements of said electrolyser. More preferably the electrical off take points are each in the form of power terminals for direct electrical connection to the water electrolyser. [0009] Preferably the water electrolyser is an anion exchange membrane (AEM) electrolyser, including a plurality of AEM cells arranged in a stack configuration. More preferably the AEM cells are electrically interconnected with one another in series.

[0010] According to a third aspect of the invention there is provided a method of constructing a solar-powered water electrolyser, said method comprising the steps of:

providing a water electrolyser adapted to receive water and being effective in electrolysis of said water to produce hydrogen;

directly coupling a printed solar photovoltaic (PV) source to the water electrolyser to power it for the production of said hydrogen.

[0011 ] Preferably the method also comprises the step of printing a plurality of PV cells on a supporting substrate to provide the printed PV source. More preferably the PV cells are directly printed on a flexible membrane which is applied to a rigid support panel to provide the printed PV source. Alternatively the PV cells are directly printed on a rigid support panel.

[0012] Preferably the step of printing the PV cells involves printing said cells in a predetermined pattern wherein direct current (DC) power provided by the printed PV source, at operating irradiances, substantially matches or is within operating power requirements of the water electrolyser. More preferably said printing step involves printing said cells wherein they are electrically connected in a predetermined series and/or parallel configuration to provide the substantially matching DC power requirements.

[0013] Preferably the method further comprises the step of forming a plurality of electrical off-take points at predetermined locations on the PV cells to provide the substantially matching DC power requirements of the water electrolyser. More preferably said forming of the off-take points involves forming power terminals each configured for direct electrical connection to the water electrolyser.

[0014] Preferably the water electrolyser is associated with a water capture generator designed for directly capturing liquid water from atmosphere to provide the water to the electrolyser. [0015] Preferably said electrolyser is also associated with a reactor designed to receive the hydrogen produced from the electrolyser and react it with carbon dioxide to produce renewable methane.

Brief Description of Drawings

[0016] In order to achieve a better understanding of the nature of the present invention a preferred embodiment of a solar-powered water electrolyser and associated aspects of the technology will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a schematic illustration of an embodiment of a printed solar photovoltaic (PV) source of one aspect of the invention;

Figure 2 is a schematic illustration of the printed solar PV source of figure 1 in the context of a solar-powered water electrolyser of an embodiment of another aspect of the invention.

Detailed Description

[0017] As seen in figures 1 and 2, there is solar-powered water electrolyser 10 of one aspect of the invention designed to produce hydrogen from water. The water supplied to the electrolyser 10 may be in the form of liquid water directly captured from atmosphere or air. The hydrogen from the electrolyser 10 produced may be reacted with carbon dioxide in a reactor to produce renewable methane. These associated technologies are disclosed in the applicant’s pending Australian provisional patent application no. 2018903181 the contents of which is to be considered included herein by way of this reference.

[0018] In this embodiment the solar-powered water electrolyser 10 generally comprises:

1. a water electrolyser 12 adapted to receive water and being effective in

electrolysis of this water to produce hydrogen;

2. a printed solar photovoltaic (PV) source 14 directly coupled to the water

electrolyser 12 to power it for the production of hydrogen. [0019] The printed PV source 14 of this example includes a plurality of PV cells 16a to 16c printed on a supporting substrate in the form of a flexible membrane 18. The supporting substrate also includes a rigid support panel 20 to which the flexible membrane 18 and the associated printed PV cells such as 16a are applied.

Importantly, the printed PV source 14 is directly coupled to the water electrolyser 12 without intermediate equipment for regulation of the DC power supplied to the electrolyser, in particular the voltage and/or the current.

[0020] The printed PV source 14 of this embodiment is configured to provide DC power to the electrolyser 12 at a voltage at least substantially equal to an operating voltage of the water electrolyser 12. The printed PV source 14 is also designed to provide DC power to the electrolyser 12 at a current less than or substantially equal to an operating current of the electrolyser 12. The printed PV cells such as 16a of the printed PV source 14 are thus configured to provide DC power, at operating irradiances, substantially matching or within operating power requirements of the water electrolyser 12. This substantially matching DC power requirement is achieved within the printed PV source 14 by any one or more of the following design

characteristics of the printed PV source 14:

1. printing the PV cells such as 16a to 16c in a predetermined pattern;

2. electrically connecting the printed PV cells 16a to 16c in a predetermined

series and/or parallel configuration.

[0021 ] Importantly, the printed PV source 14 also includes a plurality of electrical off-take points such as 22a to 22c and 24. It will be understood that the DC power provided by the printed PV source 14 depends on selection of the off-take point 22a to 22c associated with respective of the printed PV cell 16a to 16c. The off-take points such as 22a are in this example in the form of power terminals for direct electrical connection to the water electrolyser 12 wherein terminal 24 is of opposite electrical polarity to the selected terminal such as 22a.

[0022] In this embodiment the water electrolyser 12 is an anion exchange membrane (AEM) electrolyser. The AEM electrolyser 12 includes a plurality of AEM cells (not illustrated) arranged in a stack configuration and electrically interconnected with one another in series. It will be understood that the AEM electrolyser 12 is associated with other balance of plant (BOP) equipment indicated in figure 2 at 26. Importantly, this BOP equipment 26 does not as required by the prior art include either:

1. a DC to DC converter for regulating voltages from the conventional rigid

silicon-based solar panels to operational voltages required by the associated electrolyser;

2. a maximum power point tracker (MPPT) to regulate the DC power provided by the solar panels so that it remains within operating power requirements of the water electrolyser.

[0023] In another aspect of the invention there is provided a method of

constructing a solar-powered water electrolyser such as that described in the embodiment of preceding aspect of the invention. The general steps involved in construction of the solar-powered water electrolyser 10 of the preceding embodiment are as follows:

1. providing a water electrolyser 12 with the capability of receiving water and being effective in electrolysis of this water to produce hydrogen;

2. directly coupling a printed solar photovoltaic (PV) source 14 to the water

electrolyser 12 to power it for the production of hydrogen.

[0024] Importantly, the method also comprises a step of printing a plurality of PV cells such as 16a to 16c on a supporting substrate 18 and 20 to provide the printed PV source 14. The PV cells such as 16a are in this example directly printed on a flexible membrane 18 which is applied to a rigid support panel 20. In an alternative arrangement, the PV cells may be directly printed on the rigid support panel such as 20.

[0025] In this embodiment printing of the PV cells such as 16a is effected wherein DC power is provided by the printed PV source 14, at operating irradiances, so that it substantially matches or is within operating power requirements of the associated water electrolyser 12. In this example the DC power provided by the printed PV source 14 is influenced by one or more of the following factors: 1. the predetermined shape or pattern at which the PV cells such as 16a are printed;

2. the arrangement of the printed cells such as 16a and 16b which are electrically connected in a predetermined series and/or parallel configuration.

[0026] The method of this embodiment further comprises the step of forming a plurality of electrical off-take points at predetermined locations on the printed PV source 14, and more particularly the PV cells such as 16a to 16c. The off-take points such as 22a are formed as power terminals configured for direct electrical connection to the water electrolyser 12. It will be understood that the DC power provided by the PV source 14 to the electrolyser 12 is dependent on the selected power terminal such as 22a and this selection is made in order to substantially match power requirements of the water electrolyser 12.

[0027] Now that a preferred embodiment of the various aspects of the solar-power water electrolyser have been described it will be apparent to those skilled in the art that they have at least the following advantages:

1. printed solar PV provides the capability for direct coupling to power water

electrolysers in the production of hydrogen;

2. the solar-powered water electrolyser does not require the additional expense of a DC to DC converter and MPPT typically required to regulate power output from the PV source;

3. the printed solar PV can be specifically designed to match or be within

specification of operating power requirements of the associated water electrolyser.

[0028] Those skilled in the art will appreciate that the invention as described herein is susceptible to variations and modifications other than those specifically described. For example, the printed PV source may be of various types including but not limited to organic or inorganic solar PV. The solar-powered water electrolyser is not limited to the AEM electrolyser of the described embodiment and extends to practically any electrolyser which is effective in the production of hydrogen from water. In constructing a solar-powered water electrolyser the printed solar PV source may take the form of PV cells directly printed on a flexible membrane off-site which are then transported to site and applied to the rigid support panel. Alternatively the PV cells may be printed on site directly onto the rigid support panel or other supporting substrate.

[0029] All such variations and modifications are to be considered within the scope of the present invention the nature of which is to be determined from the foregoing description.