NON-THERMAL DOWNPIT RADIOISOTOPE ENERGY SOURCE FOR USE IN A BOREHOLE

Abstract

Some implementations include a downhole power source positioned in a borehole to supply electrical power to an electrical device in the borehole. The downhole power source includes a radioisotope source positioned in the borehole to emit radiation. One or more semiconductor layers positioned in the borehole can be configured to capture the radiation emitted by the radioisotope source and to generate electrical power based on the captured radiation. Figure for the abstract: Fig. 1

Description

Title of the invention: NON-THERMAL DOWNBOTTOM RADIOISOTOPE ENERGY SOURCE FOR OPERATION IN A BOREHOLE

[0001] Context

[0002] Powering downhole tools and equipment is generally achieved by cables running from the surface to the well, by using a downhole turbine for electricity generation, or by using batteries in a tool with limited lifespan and charge capacity. Conventional approaches can be expensive. These conventional approaches can also limit the operating window, particularly in the case of batteries and turbine generators, which require a constant output to generate power. Brief description of the drawings

[0003] The embodiments of the invention can be better understood by referring to the accompanying drawings.

[0004] [Fig. 1] represents an example of a downhole radio-voltaic non-thermal energy source and an electrical device powered by the downhole radio-voltaic non-thermal energy source, according to certain embodiments.

[0005] [Fig.2] represents an example of a well completion system, according to some methods of implementation.

[0006] [Fig.3] represents an example of a cross-section of a mandrel containing the downhole radio-voltaic non-thermal energy source, according to certain embodiments

[0007] [Fig.4] represents a flowchart of examples of feeding operations of the downhole electrical devices, according to certain embodiments. Detailed description

[0008] The following description includes examples of systems, processes, techniques, and program flows that implement certain aspects of the disclosure. However, it is understood that this disclosure can be implemented without these specific details. In other cases, well-known instructions, protocols, structures, and techniques have not been presented in detail so as not to obscure the description.

[0009] Embodiments may include a non-thermal radio-voltaic energy source positioned at the bottom of a borehole to generate energy independently of the thermal conditions in the borehole. The sources Non-thermal radio-voltaic power sources can produce energy for many years, even decades, under downhole conditions due to their robust construction. In contrast, under such conditions, a traditional battery may have a lifespan measured in weeks or months. Furthermore, non-thermal radio-voltaic power sources can power any type of downhole device (such as sensors and other downhole tools) without external cables or other moving parts. Consequently, embodiments can power downhole devices to allow these devices to continue operating even after a well is sealed and / or long after a traditional downhole battery has been depleted. Problems associated with battery degradation in high-temperature applications can also be avoided.

[0010] Example of a non-thermal radio-voltaic energy source at the bottom of a well

[0011] An example of a non-thermal radio-voltaic energy source at the bottom of a well is now described. [Fig. 1] represents an example of a downhole radiovoltaic non-thermal energy source and an electrical device powered by the downhole radiovoltaic non-thermal energy source, according to certain embodiments. [Fig. 1] represents a downhole radiovoltaic non-thermal energy source 100 electrically coupled to an electrical device 106. The downhole radiovoltaic non-thermal energy source 100 may include a radioisotope source 102 and one or more semiconductor layers 104.

[0012] In some embodiments, the radioisotope source 102 may comprise tritium, but a number of different radioisotopes may be used as the radioisotope source 102. The radioisotope source 102 may be in the form of a solid sheet, although other configurations are possible. The radioisotope source 102 may emit alpha, beta, and / or gamma particles as radiation. The radioisotope source 102 and the semiconductor layers 104 may be configured to be positioned close to each other. The semiconductor layers 104 may be configured to capture the particles emitted as radiation by the radioisotope source 102.The downhole radiovoltaic non-thermal energy source 100 can produce electrical energy by converting alpha, beta, and / or gamma radiation emitted by the radioisotope source 102 and captured by the semiconductor layers 104. In some embodiments, the semiconductor layers 104 may be part of a solid-state multilayer semiconductor structure comprising one or more PN junctions and electric fields between the layers. The semiconductor layers 104 may comprise a P-type semiconductor, an N-type semiconductor, or a combination of one or more semiconductors. Type P and type N layers. In some embodiments, the semiconductor layers 104 may have different thicknesses to capture the different types of particles emitted by the radioisotope source 102. In some implementations, the semiconductor layers 104 may comprise one or more thin layers of silicon, diamond, or other materials that have high energy conversion efficiency and can withstand the radiation emitted by the radioisotope source 102.

[0013] Rather than using a thermal differential between the semiconductor layers 104 to produce electricity, the downhole radiovoltaic non-thermal energy source 100 uses particles radiated by the radioisotope source 102. Some of the particles emitted by the radioisotope source 102 (for example, beta particles) can be captured by the semiconductor layers 104. The kinetic energy of the particles can be converted into electrical energy by the semiconductor layers 104 at a pn junction diode separated by a depletion region. When a radiated particle enters the semiconductor layers 104, it can deposit its energy and create electron-hole pairs separated by an electric field. The electrons and holes then flow in opposite directions, creating a current that can be used to power an external circuit.Holes can accumulate on the positive face 108 of the semiconductor layers 104, while electrons move towards the negative face 110 due to the potential integrated at the pn junction between the P-type and N-type layers. Electrons can then flow through a circuit coupled to an electrical device 106 to reach their respective holes, thus supplying energy to the electrical device 106. The downhole radio-voltaic non-thermal energy source 100 can be used for low-power applications, for example, on the milliwatt or microwatt scale. In some embodiments, several downhole radio-voltaic non-thermal energy sources 100 can be combined in series to provide a higher output energy.

[0014] The electrical device 206 can be any type of downhole device that uses electrical energy. For example, the electrical device 106 can be one or more microcontrollers, sensors, or motors, depending on their power requirements. In other embodiments, the electrical device 106 can be an energy storage device (e.g., a battery, a capacitor, a solenoid, etc.). In some implementations, the radioisotope source 102 can be configured to power other components used in drilling tools, as well as to charge capacitors, batteries, or other downhole energy storage devices. In some implementations, the downhole energy storage system can be used in conjunction with the source 100. non-thermal radio-voltaic downhole energy to power an electronic component such as a sensor for a limited time. In some embodiments, the radioisotope source 102 and the semiconductor layers 104 can be installed inside the electrical device 106. Example of a system

[0015] Examples of downhole radio-voltaic non-thermal energy sources can be used in any downhole system / application (e.g., production, completion, drilling, etc.). An example of a well completion system using the downhole radio-voltaic non-thermal energy source of [Fig. 1] is now described. [Fig. 2] illustrates an example of a well completion system according to certain embodiments. A well completion system 200 may include a borehole 212 that intersects a subsurface formation 220. The borehole 212 may include a vertical section 214 (which is at least partially cemented with a casing column 216) and a horizontal section 218. The horizontal section 218 may be an open section of the borehole 212. Other well configurations may also be suitable.

[0016] Positioned in the borehole 212 and extending from the surface, the casing column 222 provides a conduit for formation fluids moving from the subsurface formation 220 to the surface and for stimulation fluids moving from the surface to the subsurface formation 220. The casing column 222 may include a production section 224 between one or more packers 226. The production section 224 may include a mandrel 235. In some implementations, the mandrel 235 may include the downhole radio-voltaic non-thermal energy source 100 of [Fig. 1].

[0017] The downhole radio-voltaic non-thermal energy source 100 positioned in the mandrel 235 can be configured to power one or more downhole devices similar to the electrical device 106 of [Fig. 1]. The downhole devices can be sensors, microcontrollers, motors, energy storage devices, etc. Although described as being positioned in the mandrel 235, downhole devices powered by a downhole radio-voltaic non-thermal energy source can be positioned anywhere in the borehole 212.

[0018] The production section 224 may include several pipe sections, including, for example, a sand screening section. The packer(s) 226 may provide a seal between the casing column 222 and the well 212, thus defining one or more production intervals 230. The production section 224 may include one or more valves 232 (for example, interval control valves) configured to control the inflow and outflow of fluid into the section 224 of production. In some embodiments, the casing column 222 may include a power generation source 240 comprising a power generation source with an output energy greater than that of the downhole radio-voltaic non-thermal power source 100 for powering various downhole electronic components, including, but not limited to, pumps, sensors, actuators, valves, sleeves, deflectors, etc.

[0019] For example, the power generation source 240 may include a processor and a turbogenerator configured to convert the fluid flow through the turbine into electrical energy.The power generation source 240 may also include a downhole energy storage device (e.g., a battery) of suitable capacity to power various downhole electronic components during initial completion and stimulation operations when fluid flow is insufficient to generate enough power from the turbine generator. The downhole energy storage device may also power the downhole electronic components in conjunction with the turbine generator. Although [Fig. 2] depicts the power generation source 240 as being positioned in an area that is not in production, it should be understood that the power generation source 240 may be positioned anywhere along the wellbore 212, including near the production section 224.

[0020] In some embodiments, the power generation source 240 may include a telemetry device 252 that can receive data from various sensors located in the borehole 212 and transmit the data to a surface control unit 228. The data may also be provided by the surface control unit 228, received by the telemetry device 252 via a wired connection from the surface, via acoustic signals, or via other means of communication. The telemetry device 252 may further transmit signals to various electronic devices located in the borehole 112 to perform functions, such as actuation of one or more valves. The surface control unit 228 may include a computer system for processing and storing the measurements collected by one or more sensors located in the borehole 212.The computer system may, among other things, include a non-transient, computer-readable storage medium (e.g., a hard drive and / or memory) capable of executing the instructions necessary to perform these tasks. In addition to collecting and processing measurements, the computer system may be capable of controlling completion, stimulation, and production operations, including, but not limited to, the installation of 226 plugs, acidification, gravel compaction, or hydraulic fracturing.

[0021] A more detailed description of an example of a mandrel 235 of [Fig. 2] is now given. [Fig. 3] shows an example of a cross-section of a mandrel containing the downhole radio-voltaic non-thermal power source, according to certain embodiments. A mandrel 303 can be disposed along a casing 301. The casing 301 is positioned in a borehole 350 formed in an underground formation 320. Although it is shown as a closed compartment with respect to the casing 301, in some embodiments the mandrel 303 can be open towards the inside of the casing 301. Other positions and configurations are possible. The mandrel 303 can be similar to the mandrel 235 of [Fig. 2], and the mandrel 303 can include a housing 327 for the power source inside. The power source housing 327 can accommodate a radioisotope source 302 and one or more semiconductor layers 304.In some embodiments, the radioisotope source 302 and the semiconductor layers 304 may be similar to the radioisotope source 102 and the semiconductor layers 104 described in [Fig. 1]. The energy source casing 327 may be a pressurized chamber set at atmospheric pressure at the surface and isolated from a formation fluid 319 flowing from the underground formation 320. In some embodiments, the energy source casing 327 may be made of metal or ceramic to prevent the leakage of certain radioactive particles, but other configurations are possible.

[0022] Like the down-well radiovoltaic non-thermal energy source 100 of [Fig. 1], the radioisotope source 302 and the semiconductor layers 304 can be configured to generate a constant, low output energy. The energy generated in the energy source housing 327 can be routed through an electrical circuit 329 to a sensor 309. In some embodiments, a transformer (not shown) may be arranged along the electrical circuit 329. The sensor 309 may be similar to the electrical device 106 described in [Fig. 1], although other devices may be used. The sensor 309 may be coupled to a controller 313, which may include a processor. In some embodiments, the controller 313 may also be intermittently powered by the radioisotope source 302 and the semiconductor layers 304.

[0023] The sensor 309 can perform measurements of the formation fluid 319. The controller 313 can be configured to receive these measurements of the formation fluid 319 from the sensor 309 at certain time intervals. In some embodiments, the controller 313 can control drilling operations based on these measurements, communicate these measurements to other devices (down the well or on the surface), etc.

[0024] For example, the controller 313 can be configured to trigger the operation of other downhole energy sources based on measurements taken by the sensor 309. For example, the controller 313 can trigger the activation of a power source that generates more energy (compared to the radioisotope source 302 and the semiconductor layers 304) to power devices that may require more energy than that supplied by the radioisotope source 302 and the semiconductor layers 304. For example, the most important power source may be a turbogenerator, a limited-life battery, etc., to provide power to the well completion system equipment 200, such as different types of flow control devices (for example, a valve 317).

[0025] For example, the sensor 309 can detect a change in the properties of the formation fluid 319, thereby triggering an action on the valve 317. In a given scenario, an area of ​​the underground formation 220 may be closed due to a suspected high water level. During a standby phase, the sensor 309 may detect that the formation fluid 319 contains a higher hydrocarbon concentration than previously measured. The hydrocarbon concentration may exceed a property threshold identified by the controller 313. Based on the measurement, the valve 317 can be actuated to the open position to allow the fluid to flow to the surface, based on the measurement obtained during the standby phase of the sensor 309. In other embodiments, the valve 317 can be configured to open when a threshold value for one or more properties of the formation fluid 319 has been reached.

[0026] The larger-capacity power generation source can be powered intermittently by a separate downhole energy storage device or by an engine that induces an initial fluid flow in the device (for example, by a turbine generator that can use the fluid flow to generate power). Once the larger-capacity power generation source has been temporarily activated to supply power to a completion or larger-scale production system in the wellbore 212, the valve 317 can be opened to allow the formation fluid 319 to enter the casing 301.

[0027] In some embodiments, if a formation property or other parameter detected by the sensor 309 during a standby phase changes beyond a defined property threshold, the controller 313 can be configured to transmit data autonomously. For example, the controller 313 transmits a signal to the surface indicating that a property threshold for a property of the formation fluid 319 has been reached. Alternatively, the controller 313 can initiate a command during a standby phase to a higher-capacity power generation source located in the borehole 212, which may be similar to the power generation source 240 of [Fig. 2]. In some embodiments, the controller 313 can be electronically coupled to the higher-capacity power generation source. The power source 240 may include components to generate a much greater output energy than the radioisotope source 302, and the command sent by the controller 313 may order the power source 240 to activate.

[0028] In other embodiments, energy can be supplied to a downhole energy storage device (not shown), such as a capacitor. The radioisotope source 302 and the semiconductor layers 304 can supply energy to the downhole energy storage device. The downhole energy storage device can be coupled to the controller 313, and the controller 313 can be configured to store electrical energy in the downhole energy storage device. The controller 313 can also be configured to control the energy storage device so that the energy storage device supplies electrical energy to the electrical device in response to a level of electrical energy stored in the downhole energy storage device exceeding an energy threshold that enables the sensor 309 to operate.

[0029] In some embodiments, the downhole storage device can supply the sensor 309 at fixed intervals or upon user command received via the controller 313. Such a configuration allows the sensor 309 to detect environmental changes for a limited time before becoming inactive again. This is known as the sleep / wake cycle. During the sleep phase, the sensor 309 can obtain measurements of the formation fluid 319. In other cases, the sensor 309 can also be configured to detect pressure changes, acoustic signals, etc. The duration of the sleep / wake cycle of the sensor 309 (or other downhole device) can be programmed before the sensor 309 is transported into the wellbore 212.This sleep / wake cycle can be set to a duration of several days or weeks (i.e., until the sensor wakes up again to take a measurement), although other durations are possible. The sleep phase can last less than a second or several seconds depending on the task to be performed. Examples of operations

[0030] Examples of operations for powering downhole electrical devices using a non-thermal radio-voltaic energy source are now described. [Fig. 4] shows a flowchart of examples of operations for powering downhole electrical devices, according to certain embodiments. A method 400 describes the example operations for powering an electrical device in a borehole. The operations of method 400 begin at block 401.

[0031] In block 401, the process 400 comprises positioning, in a borehole, a downhole energy source that includes a radioisotope source for emitting radiation and one or more semiconductor layers for capturing the radiation emitted by the radioisotope source and for generating electrical energy based on the captured radiation. For example, with reference to FIGS. 1-2, a downhole energy source comprising the radioisotope source 102 and one or more semiconductor layers 104 can be positioned in borehole 212. The radioisotope source 102 can emit radiation such as beta particles that can induce an electric current to generate electrical energy when captured by one or more semiconductor layers 104. The flow passes to block 403.

[0032] In block 403, process 400 further consists of powering the electrical device using electrical energy generated from the captured radiation. For example, with reference to [Fig. 3], the captured radiation emitted by the radioisotope source 302 can induce a current used to power the electrical circuit 329. The electrical circuit 329 can be coupled to a downhole device and can power one or more downhole devices such as the sensor 309. The flow of process 400 then stops.

[0033] Although the disclosure aspects are described with reference to various implementations and operations, it is understood that these aspects are illustrative and that the scope of the claims is not limited to them. In general, the downhole power generation techniques described herein can be implemented with installations compatible with any hardware system or hardware systems. Numerous variations, modifications, additions, and improvements are possible.

[0034] Multiple instances may be provided for the components, operations, or structures described herein as a single instance. Furthermore, the boundaries between the various components, operations, and data stores are somewhat arbitrary, and particular operations are illustrated in the context of specific illustrative configurations. Other feature assignments are envisaged and may fall within the scope of this disclosure. In general, structures and features presented as separate components in the configuration examples may be implemented as a combined structure or component. Similarly, structures and features presented as a single element may be implemented as separate elements. These variations, modifications, additions, and enhancements, as well as others, may fall within the scope of this disclosure. Implementation methods#:

[0035] Embodiment #1: A downhole power source to be positioned in a borehole to provide electrical power to an electrical device in the borehole, the downhole power source comprising: a radioisotope source to be positioned in the borehole to emit radiation; and one or more semiconductor layers to be positioned in the borehole to capture the radiation emitted by the radioisotope source and to generate electrical power on the basis of the captured radiation.

[0036] Embodiment #2: The downhole energy source of Embodiment 1, in which one or more semiconductor layers generate electrical energy independently of the thermal emission from the radioisotope source.

[0037] Embodiment #3: The downhole power source of one of Embodiments 1-2, wherein the semiconductor layer(s) must be electrically coupled to the electrical device to be positioned in the borehole to supply electrical power from the semiconductor layer(s) to the electrical device.

[0038] Embodiment #4: The downhole energy source of Embodiment 3, in which one or more semiconductor layers are to be electrically coupled to an energy storage device to be positioned in the borehole.

[0039] Embodiment #5: The downhole power source of Embodiment 4, wherein the energy storage device includes at least one capacitor, one battery and one solenoid.

[0040] Embodiment #6: The downhole energy source of any of Embodiments 4-5, wherein one or more semiconductor layers are electrically coupled to an energy controller, wherein the energy controller is configured to store electrical energy in the energy storage device, and wherein the energy controller is configured to control the energy storage device so that the energy storage device supplies electrical energy to the electrical device in response to a level of electrical energy stored in the energy storage device exceeding an energy threshold to enable operation of the electrical device.

[0041] Embodiment #7: The downhole energy source of any of Embodiments 3-6, wherein the semiconductor layer(s) are electrically coupled to an energy controller, the energy controller being electrically coupled to a different downhole energy source that is to generate different electrical energy that is greater than the electrical energy generated on the basis of the captured radiation, the electrical device comprising a sensor for measuring a property of an underground formation in which the borehole is formed, and the energy controller must control the different bottom-well energy source so that it starts generating different electrical energy in response to the sensor measuring a value of the underground formation property that exceeds a property threshold.

[0042] Embodiment #8: Downhole system for use in a borehole, the downhole system comprising: a radioisotope source to be positioned in the borehole to emit radiation; one or more semiconductor layers to be positioned in the borehole to capture the radiation emitted by the radioisotope source and to generate electrical energy on the basis of the captured radiation; and an electrical device configured to be electrically coupled to one or more semiconductor layers.

[0043] Embodiment #9: The downhole system of Embodiment 8, in which one or more semiconductor layers generate electrical energy independently of the thermal emission from the radioisotope source.

[0044] Embodiment #10: The downhole system of one of the Embodiments 8-9, further comprising: an energy storage device which shall be electrically coupled to one or more semiconductor layers.

[0045] Embodiment #11: The downhole system of Embodiment 10, wherein the energy storage device includes at least one capacitor, one battery and one solenoid.

[0046] Embodiment #12: The downhole system of any of the Embodiments 10-11, further comprising: an energy controller configured to store electrical energy in the energy storage device, and the energy controller being configured to control the energy storage device so that the energy storage device supplies electrical energy to the electrical device in response to a level of electrical energy stored in the energy storage device exceeding an energy threshold to enable operation of the electrical device.

[0047] Embodiment #13: The downhole system of any of the Embodiments 8-12, wherein the electrical device includes a sensor for measuring a property of a subsurface formation in which the borehole is formed, the downhole system further comprising: a different downhole energy source that is to generate different electrical energy that is greater than the electrical energy generated on the basis of the captured radiation; and an energy controller for controlling the different downhole energy source to cause the different downhole energy source to initiate the generation of the different electrical energy in response to the sensor measuring a value of the property of the subsurface formation that exceeds a property threshold.

[0048] Embodiment #14: A method for supplying electrical power to an electrical device in a borehole, comprising: positioning, in the borehole, a downhole power source which includes a radioisotope source for emitting radiation and one or more semiconductor layers for capturing the radiation emitted by the radioisotope source and for generating electrical power on the basis of the captured radiation; and supplying the electrical device with the electrical power generated on the basis of the captured radiation.

[0049] Embodiment #15: The method of Embodiment 14, in which one or more semiconductor layers generate electrical energy independently of the thermal emission from the radioisotope source.

[0050] Embodiment #16: The method of any of Embodiments 14-15, further comprising the storage of electrical energy in an energy storage device positioned in the borehole.

[0051] Embodiment #17: The method of Embodiment 16, further comprising: the determination of a level of electrical energy stored in the energy storage device, wherein the power supply of the electrical device includes supplying the electrical energy stored in the energy storage device to the electrical device, in response to the level of electrical energy stored in the energy storage device exceeding an energy threshold to allow the operation of the electrical device.

[0052] Embodiment #18: The method of one of Embodiments 16-17, wherein the electrical device includes a sensor for measuring a property of an underground formation in which the borehole is formed.

[0053] Embodiment #19: The method of Embodiment 18, further comprising: measuring, using the sensor, a value of the property of the underground formation; and triggering the production of different electrical energy from a different downhole energy source in response to the property value exceeding a property threshold.

[0054] Embodiment #20: The method of Embodiment 19, in which the different electrical energy is greater than the electrical energy generated on the basis of the captured radiation.

[0055] The use of the expression "at least one of" preceding a list with the conjunction "and" shall not be considered an exclusive list and shall not be interpreted as a list of categories with one element from each category, unless expressly stated otherwise. A clause stating "at least one of elements A, B, and C" may be infringed with only one of the listed elements, several of the enumerated elements, one or more of the elements in the list and another element that is not enumerated.

[0056] In this document, the term "or" is inclusive unless explicitly stated otherwise. Thus, the phrase "at least one of the elements A, B or C" is satisfied by any element of the set {A, B, C] or any combination thereof, including multiples of any element.

Claims

Claims

1. A downhole power source for positioning in a wellbore to provide electrical power to an electrical device in the wellbore, the downhole power source comprising: a radioisotope source positioned in the wellbore to emit radiation; and one or more semiconductor layers positioned in the wellbore to capture radiation emitted by the radioisotope source and generate electrical power based on the captured radiation.

2. The downhole power source of claim 1, one or more semiconductor layers generating electrical energy independently of thermal emission from the radioisotope source.

3. The downhole power source of any one of claims 1-2, wherein the at least one semiconductor layer is to be electrically coupled to the electrical device to be positioned in the wellbore to provide electrical power from the at least one semiconductor layer to the electrical device, and, optionally, the at least one semiconductor layer is to be electrically coupled to the electrical device, wherein one or more semiconductor layers are electrically coupled to an energy controller, the energy controller is electrically coupled to another downhole power source that is to generate different electrical power, greater than the electrical power generated based on the captured radiation, the electrical device comprising a sensor for measuring a property of a subterranean formation in which the wellbore is formed,and the energy controller to control the different downhole energy source to begin generating different electrical energy in response to the sensor measuring a value of the subterranean formation property that exceeds a property threshold.,

4. The downhole power source of claim 3, one or more semiconductor layers to be electrically coupled to an energy storage device to be positioned in the wellbore, and, optionally, the energy storage device comprising at least one capacitor, a battery, and a solenoid.

5. The downhole power source of claim 4, wherein one or more semiconductor layers are electrically coupled to an energy controller, the energy controller is configured to store electrical energy in the energy storage device, and the energy controller is configured to control the energy storage device such that the energy storage device provides electrical energy to the electrical device in response to a level of electrical energy stored in the energy storage device exceeding an energy threshold to enable operation of the electrical device.

6. The downhole system for use in a wellbore, the downhole system comprising: a radioisotope source to be positioned in the wellbore to emit radiation; and one or more semiconductor layers positioned in the wellbore to capture radiation emitted by the radioisotope source and generate electrical energy based on the captured radiation; and an electrical device configured to be electrically coupled to the one or more semiconductor layers.

7. The drilling system of claim 6, one or more semiconductor layers generating electrical energy independently of thermal emission from the radioisotope source.

8. The downhole system of one of claims 6 to 7, further comprising: an energy storage device to be electrically coupled to one or more semiconductor layers, and, optionally, wherein the energy storage device comprises at least one capacitor, a battery, and a solenoid.

9. The downhole system of claim 8, further comprising: an energy controller configured to store electrical energy in the energy storage device, and the energy controller being configured to control the energy storage device such that the energy storage device provides electrical energy to the electrical device in response to a level of electrical energy stored in the energy storage device exceeding an energy threshold to enable operation of the electrical device.

10. The downhole system of claim 6, wherein the electrical device comprises a sensor for measuring a property of a subterranean formation in which the wellbore is formed, the downhole system further comprising: a different downhole power source to generate different electrical power, greater than the electrical power generated based on the captured radiation; and an energy controller to control the different downhole power source to begin generating different electrical power in response to the sensor measuring a value of the property of the subterranean formation that exceeds a property threshold.

11. A method for supplying electrical power to an electrical device in a wellbore, the method comprising: positioning, in a wellbore, a downhole power source that includes a radioisotope source for emitting radiation and one or more semiconductor layers for capturing radiation emitted by the radioisotope source and for generating electrical power based on the captured radiation; and supplying electrical power to the electrical device using electrical power generated by the captured radiation.

12. The method of claim 11, one or more semiconductor layers generating electrical energy independently of thermal emission from the radioisotope source.

13. The method of one of claims 11 to 12, further comprising: storing the electrical energy in an energy storage device positioned in the wellbore; and, optionally, measuring, via the electrical device, a property of a subterranean formation in which the wellbore is formed, the electrical device comprising a sensor.

14. The method of claim 13, further comprising: determining a level of electrical energy stored in the energy storage device, powering the electrical device comprising, supplying the electrical energy stored in the energy storage device to the electrical device, in response to the level of electrical energy stored in the energy storage device exceeding an energy threshold to enable operation of the electrical device.

15. The method of one of claims 13 to 14, further comprising: measuring, using the sensor, a value of the property of the subterranean formation; and initiating generation of different electrical energy from a different downhole energy source in response to the value of the property exceeding a property threshold, optionally, wherein the different electrical energy is greater than the electrical energy generated based on the captured radiation.

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