GOVERNMENT SUPPORT STATEMENT

[0001] This invention was made with government support under DE-AC02-06CH11357 awarded by the Department of Energy. The government has certain rights in this invention.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

[0002] The present application claims the benefit of and priority to U.S. Provisional Patent Application No. 63/106,586, filed October 28, 2020, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0003] The present disclosure relates generally to natural gas compressors for natural gas vehicles.

BACKGROUND

[0004] Natural gas has become a more common fuel source over recent years. When compared to other fuel sources used in internal combustion engines, natural gas engines tend to produce less nitrogen oxide (NOx) and greenhouse emissions. Natural gas engines also tend to be more cost- effective due to the abundance of natural gas.

[0005] Generally, a natural gas compressor may be used with a natural gas vehicle. Typical natural gas compressors are stand-alone systems that are fueled by natural gas or powered through electricity. At times, the cost of operating the natural gas compressor on electricity is higher than the cost of operating the natural gas compressor on natural gas. Additionally, a stand-alone compressor is an additional purchased piece of equipment, which may not be cost-effective. SUMMARY

[0006] One embodiment of the present disclosure relates to a natural gas vehicle including a fuel tank, a natural gas internal combustion engine, a fuel conduit, and a natural gas compressor. The natural gas internal combustion engine is configured to produce a mechanical output. The natural gas internal combustion engine is fluidly coupled to the fuel tank. The natural gas compressor is operatively coupled to the natural gas internal combustion engine and utilizes the mechanical output to operate the natural gas compressor. The fuel conduit provides fuel. The natural gas compressor is fluidly coupled to the fuel tank. The natural gas compressor is fluidly coupled to the fuel conduit. The natural gas compressor is configured to receive the fuel from the fuel conduit, compress the fuel from the fuel conduit, and provide compressed fuel to the fuel tank.

[0007] Another embodiment of the present disclosure relates to a vehicle. The vehicle includes a chassis, a vehicle body coupled to the chassis, and a powertrain system coupled to the chassis. The powertrain system includes a fuel tank, an internal combustion engine, and a natural gas compressor. The internal combustion engine is fluidly coupled to the fuel tank and is configured to utilize fuel in both a lower pressure state and a high pressure state. The natural gas compressor is operably coupled to the internal combustion engine. An inlet to the natural gas compressor is fluidly coupleable to an external fuel source that is separate from the fuel tank. An outer of the natural gas compressor is fluidly coupled to the fuel tank.

[0008] Yet another embodiment of the present disclosure relates to a system including a natural gas internal combustion engine; a natural gas compressor operably coupled to the natural gas internal combustion engine; a fuel sensor configured to monitor an amount of fuel in a fuel tank; and a fuel control unit communicably coupled to the natural gas internal combustion engine, the natural gas compressor, and the fuel sensor. The fuel control unit includes a memory storing machine readable instructions and a processor. The machine readable instructions are structured to cause the processor to perform operations including activating the natural gas compressor by coupling the natural gas internal combustion engine to the natural gas compressor; receiving, from the fuel sensor, an indication of the amount of fuel in the fuel tank; and deactivating the natural gas internal combustion engine in response to the amount of fuel satisfying a fuel threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a block schematic of an example natural gas vehicle with a compressor coupled to a natural gas engine;

[0010] Figure 2 is a block schematic of another example natural gas vehicle with the compressor coupled to a transmission power take-off;

[0011] Figure 3 is a block schematic of a hybrid vehicle with a compressor coupled to an engine;

100121 Figure 4 is a block schematic of another hybrid vehicle with the compressor coupled to an electric motor;

[0013] Figure 5 is a flowchart showing an example process performed by a controller of a natural gas vehicle; and

[0014] Figure 6 is a flowchart showing another example process performed by a controller of a natural gas vehicle.

[0015] It will be recognized that the Figures are schematic representations for purposes of illustration. The Figure are provided for the purpose of illustrating one or more implementations with the explicit understanding that the Figures will not be used to limit the scope or the meaning of the claims.

DETAILED DESCRIPTION

[0016] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and systems for incorporating a natural gas compressor into a natural gas vehicle (NGV). The methods, apparatuses, and systems introduced above and discussed in greater detail below may be implemented in various ways, as the described concepts are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided primarily for illustrative purposes. [0017] Figure 1 depicts a block schematic of an example NGV 100. The NGV 100 may be an on-road or an off-road vehicle including, but not limited to, line-haul trucks, mid-range trucks (e.g., pick-up trucks), cars, boats, tanks, airplanes, locomotives, mining equipment, and any other type of vehicle. The NGV 100 includes a chassis 10 (e.g., frame, etc.) and a vehicle body 20 coupled to the chassis 10. The vehicle body 20 may define a cab area for the NGV 100 that accommodates occupants of the NGV 100. The cab may be an enclosure that protects an occupant from environmental and road hazards. The cab may also include an instrument panel that provides a user with diagnostic information about the NGV 100 and includes controls (e.g., steering wheel, throttle and brake pedals, signals, etc.) to facilitate vehicle operations. The NGV 100 includes a powertrain system 102 coupled to the chassis 10. In various embodiments, the powertrain system 102 includes an engine system, a transmission system, a drive shaft system, a differential system, and additional vehicle subsystems, etc. The powertrain system 102 may include additional, fewer, and/or different components/sy stems such that the principles, methods, systems, apparatuses, processes, and the like of the present disclosure are applicable to any other vehicle configuration.

[0018] The powertrain system 102 includes a fuel tank 104 (e.g., fuel source, fuel supply, pipeline) and a first external fuel conduit 105 (e.g., fuel line, pipeline). The fuel tank 104 stores high pressure fuel (e.g., natural gas, gaseous fuel, lean bum gas, bi-fuel, propane, liquid propane, liquid natural gas, biogas, etc.) for use in combustion and provides the fuel to a fuel line. In some embodiments, the fuel is in a low pressure state.

[0019] The first external fuel conduit 105 is removably coupled to the fuel tank 104 at a first end of the first external fuel conduit 105. The first external fuel conduit 105 is disposed external to the NGV 100 and may be removably coupled to other vehicles or to a natural gas supply line at a second end. The fuel tank 104 is fluidly coupled to the first external fuel conduit 105. The fuel tank 104 is configured to receive high pressure fuel from the first external fuel conduit 105. For example, the fuel tank 104 can be re-fueled by a natural gas supply line through the first external fuel conduit 105. The fuel tank 104 is also configured to provide high pressure fuel to the first external fuel conduit 105.

[0020] The powertrain system 102 also includes a fuel control regulator 106 (e.g., solenoid valve). The fuel control regulator 106 is fluidly coupled to the fuel tank 104 and is configured to receive high pressure fuel from the fuel tank 104 through a fuel line. The fuel control regulator 106 is operable between an open position and a closed position. In the closed position, the flow of the fuel through the fuel control regulator 106 is stopped (e.g., blocked, prohibited) by the fuel control regulator 106. Between the open position and the closed position, the flow of the fuel through the fuel control regulator 106 is restricted (e.g., decreased, limited) by the fuel control regulator 106. In the open position, flow of the fuel through the fuel control regulator 106 is not restricted by the fuel control regulator 106. After passing through the fuel control regulator 106, the fuel expands, which causes the fuel to enter a low pressure state. In some embodiments, the fuel remains in a high pressure state.

[0021] The powertrain system 102 also includes an internal combustion engine 108 (e.g., natural gas internal combustion engine, lean-bum internal combustion engine, biofuel internal combustion engine, bi-fuel internal combustion engine). The internal combustion engine 108 is fluidly coupled to the fuel control regulator 106 and is configured to receive low pressure fuel from the fuel control regulator 106. In some embodiments, the internal combustion engine 108 utilizes fuel in a high pressure state. The internal combustion engine 108 combusts the fuel to generate power and is defined by an output (e.g., power, rating). The internal combustion engine 108 is structured as a spark-ignition engine. In various embodiments, the internal combustion engine 108 is structured as a compression-ignition system.

[0022] The powertrain system 102 also includes a transmission 110 (e.g., gearbox). The transmission 110 is coupled to the internal combustion engine 108 through a crankshaft. The output of the internal combustion engine 108 is transferred through the crankshaft to the transmission 110. The transmission 110 is configured to transform the output received by the internal combustion engine 108 and provide the transformed output to an output shaft 112. The output shaft 112 transmits the transformed output to the wheels of the NGV 100 through a differential system.

[0023] The powertrain system 102 also includes a compressor 114. The compressor 114 is mechanically coupled to the internal combustion engine 108. In some embodiments, the compressor 114 is hydraulically coupled to internal combustion engine 108. The compressor 114 utilizes the output transmitted from the internal combustion engine 108 to compress fuel (e.g., increase a pressure of the fuel) in order to re-fuel the fuel tank 104 or other vehicles. The NGV 100 is configured to select the output of the internal combustion engine 108. For example, a user (e.g., operator) of the NGV 100 may select the internal combustion engine 108 to power the transmission 110. When the transmission 110 receives the output of the internal combustion engine 108, the NGV 100 is driven as a traditional vehicle. When the user of the NGV 100 selects that the compressor 114 is to receive the output of the internal combustion engine 108, the output of the internal combustion engine 108 is utilized to compress fuel in order to re-fuel the fuel tank 104 or fuel of additional vehicles. In some embodiments, the output of the internal combustion engine 108 is utilized by the transmission 110 and the compressor 114. In these embodiments, the NGV 100 may be driven without disrupting the function of the compressor 114. This is advantageous if the position of the NGV 100 needs to be adjusted during a re-fuel.

[0024] The compressor 114 is fluidly coupled to an external fuel supply 116 (e.g., fuel tank, fuel supply, pipeline) and is configured to receive fuel from the external fuel supply 116. The external fuel supply 116 is configured to provide low pressure fuel to the compressor 114. The compressor 114 compresses the low pressure fuel to convert it into high pressure fuel. In various embodiments, the pressure of the high pressure fuel is approximately equal to (e.g., within 5% of) between 1,000 to 5,000 PSI. The compressor 114 is also fluidly coupled to the fuel tank 104 and is configured to provide the high pressure fuel to the fuel tank 104.

[0025] The powertrain system 102 may include a second external fuel conduit 117 (e.g., fuel line, pipeline). The second external fuel conduit 117 is fluidly coupled to the compressor 114. The NGV 100 exports the high pressure fuel compressed by the compressor 114 to an external source through the second external fuel conduit 117. The external source may include other vehicles (e.g., external internal combustion engines, vehicle fuel tanks, etc.) or storage tanks. In some embodiments, the second external fuel conduit 117 may include a plurality of supply lines. The supply lines are used to refuel a plurality of external sources simultaneously, allowing the user to set up the exporting of the fuel during a single instance. The user of the NGV 100 can determine whether the high pressure fuel compressed by the compressor 114 is provided to the fuel tank 104 or the external source through the second external fuel conduit 117. In some embodiments, the NGV 100 exports the high pressure fuel from the fuel tank 104 to the external source through the first external fuel conduit 105. [0026] The NGV 100 also includes a controller 118 (e.g., fuel controller, fuel module, fuel control unit, fuel control circuit, etc.). The controller 118 includes a processing circuit 120. The processing circuit 120 includes a processor 122 and a memory 124. The processor 122 may include a microprocessor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc., or combinations thereof. The memory 124 may include, but is not limited to, electronic, optical, magnetic, or any other storage or transmission device capable of providing a processor, ASIC, FPGA, etc. with program instructions. This memory 124 may include a memory chip, Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), flash memory, or any other suitable memory from which the controller 118 can read instructions. The instructions may include code from any suitable programming language. The memory 124 may include various modules that include instructions which are configured to be implemented by the processor 122.

10027 [ In various embodiments, the controller 118 is configured to communicate with a central controller 126 (e.g., engine control unit (ECU), engine control module (ECM), etc.) of a NGV 100. In some embodiments, the central controller 126 and the controller 118 are integrated into a single controller.

[0028] In some embodiments, the central controller 126 is communicable with a display device (e.g., screen, monitor, touch screen, heads up display (HUD), indicator light, etc.). The display device may be configured to change state in response to receiving information from the central controller 126. For example, the display device may be configured to change between a static state (e.g., displaying a green light, displaying a “SYSTEM OK” message) and an alarm state (e.g., displaying a blinking red light, displaying a “SERVICE NEEDED” message) based on receiving information from the central controller 126. By changing the state, the display device may provide an indication to the user of a status (e.g., operation, in need of service) of the powertrain system 102.

[0029] The controller 118 is configured to communicate with any and/or all of the fuel tank 104 (e.g., a fuel sensor 107 disposed in the fuel tank such as a fuel pressure sensor, fuel level sensor, etc.), the fuel control regulator 106, the internal combustion engine 108, the transmission 110, and the compressor 114. The controller 118 monitors and controls the re-fueling process. For example, after the user has started the compressor 114, the controller 118 monitors the fuel capacity of the fuel tank 104. For example, the controller 118 may receive, from a fuel sensor, an indication of the amount of fuel in the fuel tank by monitoring the fuel pressure in the fuel tank 104, a fuel level in the fuel tank 104, or another metric indicative of fuel quantity. Once the fuel tank 104 has been re-fueled to the desired amount (e.g., once a fuel threshold has been satisfied as indicated by the fuel sensor), the controller 118 stops the compressor 114. The controller 118 then communicates with the central controller 126 to turn off the NGV 100, allowing the user to leave the NGV 100 to be re-fueled without the need to monitor it.

[0030] In some embodiments, the central controller 126 is communicable (e.g., via cellular radio, Bluetooth, Wi-Fi, etc.) with a wireless device, such as a mobile phone, laptop, or tablet. In some embodiments, the wireless device is be configured to transmit a message to the central controller 126. For example, the wireless device may provide a user with the expected duration to complete re-fueling based on information received from the central controller 126.

[0031] In some embodiments, the wireless device of the central controller 126 is communicable with an external server (e.g., webserver, intranet, internet, Internet of Things, Vehicle-to-Everything). The wireless device may be configured to retrieve information from the external server and provide the information to the central controller 126 and the controller 118. The information may be retrieved periodically (e.g., every minute, hourly, daily), before the start of fuel compression, or manually by the user. The user may also manually program the information into the central controller 126.

[0032] Figure 2 depicts a block schematic of an example NGV 100 according to another embodiment. In the embodiment of Figure 2, the transmission 110 includes a transmission power take-off 202. The transmission power take-off 202 diverts output received from the internal combustion engine 108 to a secondary application. The compressor 114 is coupled to the transmission power take-off 202. The transmission power take-off 202 diverts the output provided from the output shaft 112 to the compressor 114. The transmission power take-off 202 is communicable with the controller 118.

]0033] Figure 3 depicts a block schematic of an example hybrid vehicle 300 according to another embodiment. In the embodiment of Figure 3, the hybrid vehicle 300 is similar in nature to the NGV 100; however, the hybrid vehicle 300 is configured to use both fuel and electric power. The hybrid vehicle 300 is configured to alternate between the fuel and the electric power to provide an output to the wheels of the hybrid vehicle 300. In some embodiments, the hybrid vehicle 300 is configured to use both the fuel and the electric power simultaneously.

[0034] The hybrid vehicle 300 includes a hybrid powertrain 302. The hybrid powertrain 302 also includes a generator 304 (e.g., turbine). The generator 304 is coupled to the internal combustion engine 108 and is configured to receive the output of the internal combustion engine 108 and convert it into electrical energy. The internal combustion engine 108 is configured to use low pressure fuel when providing the output to the generator 304. In some embodiments, the internal combustion engine 108 is configured to use high pressure fuel when providing the output to the generator 304.

[0035] The hybrid vehicle 300 also includes a battery 306. The battery 306 provides electricity to the hybrid vehicle 300. The battery 306 may be the only battery for the hybrid vehicle 300. In some embodiments, the battery 306 is dedicated for the hybrid powertrain 302. The battery 306 is electrically communicable with the generator 304 and the battery 306 is configured to be recharged by the generator 304.

[0036] The hybrid vehicle 300 also includes an electric motor 308 (e.g., electromotor, electrical engine). The electric motor 308 is electrically communicable with the generator 304 and is configured to receive electricity from the battery 306. The electric motor 308 converts electrical energy into a mechanical output. The electric motor 308 is defined by an output (e.g., power, rating). The electric motor 308 provides the output to the wheels to the hybrid vehicle 300. The user may decide whether to power the hybrid vehicle 300 using the electric motor 308 or the internal combustion engine 108. In some embodiments, the hybrid vehicle 300 may use both the electric motor 308 and the internal combustion engine 108 to power the hybrid vehicle 300.

[0037] Figure 4 depicts a block schematic of an example hybrid vehicle 300 according to another embodiment. In the embodiment of Figure 4, the compressor 114 is coupled to the electric motor 308. The electric motor 308 provides an output to the compressor 114 so that the compressor can operate. [0038] The hybrid vehicle 300 is removably coupled to a first end of an external electric conduit 310. The external electric conduit 310 is electrically communicable with the battery 306 and is configured to receive charge from the battery 306. The second end of the external electric conduit 310 is coupled to an external electric compressor and configured to provide electricity to the external electric compressor. In some embodiments, the hybrid vehicle 300 includes a connection port (e.g., adapter, etc.) by which an external electric compressor may be connected to the battery 306 and/or generator 304. The external electric compressor may be used to provide high pressure fuel to the hybrid vehicle 300 or to other vehicles. This is advantageous as it offers the user the opportunity to select whether to use electricity generated by the generator 304 or the compressor 114 of the hybrid vehicle to produce high pressure fuel. The user may make the selection based on the availability of fuel and/or the cost of using fuel compared to using electricity. The second end of the external electric conduit 310 may be coupled to an external battery and be configured to charge the external battery.

[0039] The external electric conduit 310 is configured to provide electricity to the hybrid vehicle 300. The electricity is used to charge the battery 306 and may be directly coupled to one, or a combination of, the battery 306 and the electric motor 308. The electricity may also be used to provide power to the electric motor 308 so that the electric motor 308 can operate the natural gas compressor 114. In various embodiments, the hybrid vehicle 300 is electrically communicable with a solar panel through the external electric conduit 310. The solar panel provides solar power, in the form of electricity, to the hybrid vehicle 300.

[0040] The controller 118 and/or the central controller 126 are configured to control operation of the hybrid powertrain 302 based on retrieved information. For example, the wireless device may retrieve the current price of electricity and the current price of natural gas from a municipality website based on the location of the hybrid vehicle 300. The wireless device then provides the price of electricity and the price of natural gas to the controller 118. Using the historical efficiency of each approach, the controller 118 can then determine the most cost effective approach to pressurize the fuel. In another example, the wireless device may retrieve information of the current carbon content (e.g., the amount of carbon generated) of an energy source from the municipality website based on the location of the hybrid vehicle 300. The wireless device then provides the current carbon content for natural gas and electricity to the controller 118. The controller 118 may then determine the approach which results in the lesser carbon content to pressurize the fuel.

[0041] In some embodiments, the controller 118 displays to the user the cost of each solution. Using a selectable clutch, the user selects the approach for pressurizing fuel. The options available to the user include, but are not limited to, using electrical power from the battery 306, electrical power from the generator 304, or electrical power from an external, local electrical grid.

[0042] Figure 5 depicts an example process 500 of refilling a fuel tank of a NGV (e.g., NGV 100, hybrid vehicle 300) having an onboard natural gas compressor 114 controlled by the controller 118, according to another embodiment. In some embodiments, the central controller 126 controls the process 500 of refilling the fuel tank of the NGV.

[0043] At 502, the controller 118 receives a signal indicative of a current amount of fuel in a fuel tank. In various embodiments, the fuel tank is for a secondary natural gas vehicle or an external fuel tank.

[0044] At 504 the controller 118 determines a duration for the natural gas compressor 114 to fill the fuel tank. The controller 118 may determine the duration to fill the fuel tank from using known programmed values provided to the controller 118. In some embodiments, the controller 118 calculates the duration by utilizing historical data available to the controller 118.

[0045] At 506 the controller 118 determines a vehicle start time of the NGV. The vehicle start time may be programmed in the controller 118 by a user of the NGV. In some embodiments, the controller 118 may receive the vehicle start time by a wireless device.

[0046] At 508 the controller 118 determines a compressor start time by comparing the vehicle start time to the duration for the natural gas compressor 114 to fill the fuel tank. For example, if the time to fill the fuel tank requires three hours, and the NGV is scheduled to be operated at 7:00 A.M., the controller 118 will determine that the natural gas compressor 114 is scheduled to start at 4:00 A.M. [0047] At 510 the controller 118 activates the natural gas compressor 114 at the compressor start time. For example, if the compressor start time is 4:00 A.M., the controller 118 then activates the natural gas compressor 114 at 4:00 A.M.

100481 In some embodiments, at 512 the controller 118 receives a signal indicative of a current in-cab temperature of the NGV. The controller 118 may receive the signal by a sensor disposed in the cab.

[0049] In some embodiments, at 514 the controller 118 determines a duration for a climate control system to heat or cool the in-cab temperature to a desired temperature. The controller 118 may determine the desired temperature utilizing the climate control system’s last-used values. For example, if the user of the NGV had the climate control system set to 72° during their last operation of the NGV, the controller 118 will determine that 72° is the desired temperature. In various embodiments, the desired temperature is programmed in the controller 118 by the user of the NGV. In some embodiments, the desired temperature is provided, to the controller 118, by the wireless device. The controller 118 may determine the duration to reach the desired temperature using known programmed values provided to the controller 118. In some embodiments, the controller 118 determines the duration to reach the desired temperature by historical data available to the controller 118.

[0050] In some embodiments, at 516 the controller 118 determines the vehicle start time of the NGV. The vehicle start time may be the same as used at 506. The vehicle start time may be programmed in the controller 118 by the user of the NGV. In some embodiments, the controller 118 receives the vehicle start time by the wireless device.

[0051] In some embodiments, at 518 the controller 118 determines a temperature start time by comparing the vehicle start time to the duration for the climate control system to heat or cool the in-cab temperature to the desired temperature. For example, if the time to reach the desired temperature is ten minutes, and the NGV is scheduled to be operated at 7:00 A.M., the controller 118 will determine that the climate control system is scheduled to start at 6:50 A.M. [0052] In some embodiments, at 520 the controller 118 activates the climate control system at the temperature start time. For example, if the temperature start time is 6:50 A.M. the central controller 126 then activates the climate control system at 6:50 A.M.

100531 Figure 6 depicts an example process 600 of refilling a fuel tank with a NGV having an onboard natural gas compressor 114 through available solar power, controlled by the controller 118, according to another embodiment. In some embodiments, the central controller 126 controls the process 600 of refilling the fuel tank with the NGV through available solar power.

[0054] The NGV receives electricity generated by a solar panel through an external electric conduit. In some embodiments, the solar panel is located on the NGV. At 602, the controller 118 determines if the NGV is scheduled to be operated for a specified amount of time. The schedule of the NGV may be programmed in the controller 118 by a user of the NGV. In some embodiments, the controller 118 receives the schedule of the NGV from a wireless device. If the NGV is scheduled to be operated, the controller 118 will remain at 602. For example, the controller 118 may require the NGV not to be refueled if the NGV is scheduled to be used within four hours; thus, if the NGV is scheduled to be operated within two hours, the controller 118 will remain at 602. The controller 118 may periodically re-determine if the NGV is scheduled to be operated.

[0055] When the NGV is not scheduled to operate, at 604 the controller 118 receives a signal indicative of available solar power. The controller 118 may receive the signal directly from a battery that receives the solar power from the solar panel. In some embodiments, the controller 118 receives the signal from the wireless device.

10056] At 606, the controller 118 determines if the available solar power exceeds an operating threshold. The operating threshold is the amount of available energy needed to operate the natural gas compressor 114 for a specified duration uninterrupted. The controller 118 determines the operating threshold by using programmed values provided to the controller 118. For example, if the operating threshold requires operating the natural gas compressor 114 for one hour uninterrupted and the available solar power is able to operate the natural gas compressor for two hours uninterrupted, the operating threshold has been exceeded. [0057] When the available solar power satisfies the operating threshold (e.g., exceeds the operating threshold, is greater than or equal to the operating threshold, etc.), at 608 the controller 118 utilizes the available solar power to operate the natural gas compressor 114. The controller 118 utilizes the available solar power until it is depleted and will then return to 602. For example, if the available solar power is capable of operating the natural gas compressor 114 for four hours uninterrupted, after the available solar power has been depleted the controller 118 will again determine if the NGV is scheduled to be operated.

[0058] When the available solar power does not satisfy the operating threshold (e.g., has not exceeded the operating threshold, is less than or equal to the operating threshold, is less than the operating threshold, etc.), at 610 the controller 118 utilizes a fuel to operate the natural gas compressor 114. While the natural gas compressor 114 is operated, the controller 118 periodically re-performs the process 600. If the available solar power exceeds the operating threshold at 606, the controller 118 stops providing the fuel to operate the natural gas compressor 114 and instead utilizes the available solar power to operate the natural gas compressor 114.

[0059] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed but rather as descriptions of features specific to particular implementations. Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

[00601 As utilized herein, the terms “substantially,” “generally,” “approximately,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims.

[0061| The term “coupled” and the like, as used herein, mean the joining of two components directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two components or the two components and any additional intermediate components being integrally formed as a single unitary body with one another, with the two components, or with the two components and any additional intermediate components being attached to one another.

[0062] The terms “fluidly coupled to” and the like, as used herein, mean the two components or objects have a pathway formed between the two components or objects in which a fluid, such as air, fuel, an gaseous fuel-air mixture, etc., may flow, either with or without intervening components or objects. Examples of fluid couplings or configurations for enabling fluid communication may include piping, channels, or any other suitable components for enabling the flow of a fluid from one component or object to another.

[0063] It is important to note that the construction and arrangement of the various systems shown in the various example implementations is illustrative only and not restrictive in character. All changes and modifications that come within the spirit and/or scope of the described implementations are desired to be protected. It should be understood that some features may not be necessary, and implementations lacking the various features may be contemplated as within the scope of the disclosure, the scope being defined by the claims that follow. When the language “a portion” is used, the item can include a portion and/or the entire item unless specifically stated to the contrary.

[0064] Also, the term “or” is used, in the context of a list of elements, in its inclusive sense (and not in its exclusive sense) so that when used to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, Z, X and Y, X and Z, Y and Z, or X, Y, and Z (i.e., any combination of X, Y, and Z). Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each be present, unless otherwise indicated.

|0065| Additionally, the use of ranges of values (e.g., W1 to W2, etc.) herein are inclusive of their maximum values and minimum values (e.g., W1 to W2 includes W1 and includes W2, etc.), unless otherwise indicated. Furthermore, a range of values (e.g., W1 to W2, etc.) does not necessarily require the inclusion of intermediate values within the range of values (e.g., W1 to W2 can include only W1 and W2, etc.), unless otherwise indicated.