Abstract: Processes for converting nitrate to ammonia are described. Nitrate is electrochemically converted in the presence of a catalyst to form a product comprising ammonia. The catalyst comprises cobalt on a support, where the support is in the form of a foil, mesh, cloth, gauze, sponge, and combinations thereof. The catalyst may alternatively comprise a cobalt in the form of a foil, mesh, cloth, gauze, sponge, and combinations thereof.

Abstract: A method for mitigating loads acting on a rotor blade of a wind turbine includes receiving a plurality of loading signals and determining at least one load acting on the rotor blade based on the loading signals. Further, the method includes determining a type of the load(s) acting on the rotor blade. Moreover, the method includes comparing the load(s) to a loading threshold, such as an extreme loading threshold. In addition, the method includes implementing a control scheme when the load(s) exceeds the loading threshold. More specifically, the control scheme includes providing a first pitching mode for reducing a first type of load, providing a different, second pitching mode for reducing a different, second type of load, and coordinating the first and second pitching modes based on the type of the at least one load to mitigate the loads acting on the rotor blade.

Abstract: A wind turbine is provided. The wind turbine includes a mechanical system, an electrical system and a controller. The controller is for determining an electrical capability limit of the electrical system according at least in part to one or more operating conditions of the wind turbine and one or more environment conditions of a site of the wind turbine, comparing the electrical capability limit of the electrical system and a mechanical capability limit of the mechanical system, and controlling the electrical system to operate at the smaller one of the electrical capability limit and the mechanical capability limit. A method for controlling a wind turbine comprising a mechanical system and an electrical system is also provided.

Abstract: A system and method are provided for controlling a wind turbine based on a collective pitch-offset. Accordingly, a wind condition acting on a rotor of the wind turbine is determined, and a first collective pitch angle for the plurality of rotor blades is set, and the wind turbine is operated. A thrust of the rotor based, at least in part, on the wind condition is determined, and an actual collective pitch angle is calculated. A collective pitch offset is determined based on the difference between the first collective pitch angle and the actual collective pitch angle. The collective pitch offset is integrated with at least one pitch setpoint command. The at least one pitch setpoint command is transmitted to a pitch control mechanism of the wind turbine.

Abstract: A method for mitigating loads acting on a rotor blade of a wind turbine includes receiving a plurality of loading signals and determining at least one load acting on the rotor blade based on the loading signals. Further, the method includes determining a type of the load(s) acting on the rotor blade. Moreover, the method includes comparing the load(s) to a loading threshold, such as an extreme loading threshold. In addition, the method includes implementing a control scheme when the load(s) exceeds the loading threshold. More specifically, the control scheme includes providing a first pitching mode for reducing a first type of load, providing a different, second pitching mode for reducing a different, second type of load, and coordinating the first and second pitching modes based on the type of the at least one load to mitigate the loads acting on the rotor blade.

Abstract: A wind turbine is provided. The wind turbine includes a mechanical system, an electrical system and a controller. The controller is for determining an electrical capability limit of the electrical system according at least in part to one or more operating conditions of the wind turbine and one or more environment conditions of a site of the wind turbine, comparing the electrical capability limit of the electrical system and a mechanical capability limit of the mechanical system, and controlling the electrical system to operate at the smaller one of the electrical capability limit and the mechanical capability limit. A method for controlling a wind turbine comprising a mechanical system and an electrical system is also provided.

Abstract: A method for controlling the operation of a wind turbine may generally include monitoring a current yaw position of a nacelle of the wind turbine, wherein the current yaw position is located within one of a plurality of yaw sectors defined for the nacelle. In addition, the method may include monitoring a wind-dependent parameter of the wind turbine and determining a variance of the wind-dependent parameter over time, wherein the variance is indicative of variations in a wind parameter associated with the wind turbine. Moreover, the method may include determining at least one curtailed operating setpoint for the wind turbine when the variance exceeds a predetermined variance threshold, wherein the curtailed operating setpoint(s) is determined based at least in part on historical wind data for the yaw sector associated with the current yaw position.

Abstract: A method for mitigating loads acting on a rotor blade of a wind turbine includes determining, via a state estimator of a controller, a blade state estimation of the rotor blade. The method also includes reconstructing, via the controller, one or more loading signals of the rotor blade from the blade state estimation using modal analysis such that the loading signal(s) include a lead time. Further, the method includes comparing the loading signal(s) of the rotor blade to a loading threshold. Moreover, the method includes implementing a control action based on the comparison such that the lead time provided by the loading signal(s) allows the control action to take effect before a damaging load occurs on the rotor blade.

Abstract: A system and method are provided for controlling a wind turbine based on a collective pitch-offset. Accordingly, a wind condition acting on a rotor of the wind turbine is determined, and a first collective pitch angle for the plurality of rotor blades is set, and the wind turbine is operated. A thrust of the rotor based, at least in part, on the wind condition is determined, and an actual collective pitch angle is calculated. A collective pitch offset is determined based on the difference between the first collective pitch angle and the actual collective pitch angle. The collective pitch offset is integrated with at least one pitch setpoint command. The at least one pitch setpoint command is transmitted to a pitch control mechanism of the wind turbine.

Abstract: Provided herein are methods and systems for converting natural gas, and specifically methane, into higher-value oxycarbon products, such as methanol, methyl formate, and formic acid. The natural gas is introduced into an aqueous solution with hydroxyl radicals and reacted in ambient conditions to form the desired products in the presence of a metal catalyst. The methods described herein overcome the “over-activation” dilemma of prior art methods that lead to the formation of undesirable carbon oxide compounds. Methods and apparatus for forming hydrogen peroxide via electrolysis and for forming hydroxyl radicals from the hydrogen peroxide via reaction with ferrous ions are also provided.

Abstract: A compound including a cation of the following structure is provided (1), wherein Q is selected from the group consisting of polymer residues and substituted or unsubstituted alkyl groups, and R is H or a polymer residue. A membrane including the above cation, and electrochemical devices employing this membrane, are also provided.

Abstract: Provided herein are methods and systems for converting natural gas, and specifically methane, into higher-value oxycarbon products, such as methanol, methyl formate, and formic acid. The natural gas is introduced into an aqueous solution with hydroxyl radicals and reacted in ambient conditions to form the desired products in the presence of a metal catalyst. The methods described herein overcome the “over-activation” dilemma of prior art methods that lead to the formation of undesirable carbon oxide compounds. Methods and apparatus for forming hydrogen peroxide via electrolysis and for forming hydroxyl radicals from the hydrogen peroxide via reaction with ferrous ions are also provided.

Abstract: A redox flow battery is provided having a double-membrane (one cation exchange membrane and one anion exchange membrane), triple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and one electrolyte positioned between and in contact with the two membranes). The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte. This design physically isolates, but ionically connects, the negative electrolyte and positive electrolyte. The physical isolation offers great freedom in choosing redox pairs in the negative electrolyte and positive electrolyte, making high voltage of redox flow batteries possible. The ionic conduction drastically reduces the overall ionic crossover between negative electrolyte and positive one, leading to high columbic efficiency.

Abstract: A method for controlling the operation of a wind turbine may generally include monitoring a current yaw position of a nacelle of the wind turbine, wherein the current yaw position is located within one of a plurality of yaw sectors defined for the nacelle. In addition, the method may include monitoring a wind-dependent parameter of the wind turbine and determining a variance of the wind-dependent parameter over time, wherein the variance is indicative of variations in a wind parameter associated with the wind turbine. Moreover, the method may include determining at least one curtailed operating setpoint for the wind turbine when the variance exceeds a predetermined variance threshold, wherein the curtailed operating setpoint(s) is determined based at least in part on historical wind data for the yaw sector associated with the current yaw position.

Abstract: A compound including a cation of the following structure is provided (1), wherein Q is selected from the group consisting of polymer residues and substituted or unsubstituted alkyl groups, and R is H or a polymer residue. A membrane including the above cation, and electrochemical devices employing this membrane, are also provided.

Abstract: A redox flow battery is provided. The redox flow battery involves multiple-membrane (at least one cation exchange membrane and at least one anion exchange membrane), multiple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and at least one electrolyte disposed between the two membranes) as the basic characteristic, such as a double-membrane, triple electrolyte (DMTE) configuration or a triple-membrane, quadruple electrolyte (TMQE) configuration. The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolyte and the positive or negative electrolyte.

Abstract: This invention provides a family of functionalized polymers capable of forming membranes having exceptional OH? ionic conductivity as well as advantageous mechanical properties. The invention also provides membranes including the provided polymers and AEMFC/HEMFC fuel cells including such membranes. In a preferred embodiment, preferred function groups include a quaternary phosphonium, and in a more preferred embodiment the provided polymer is (tris(2,4,6-trimethoxyphenyl)phosphine)3 functionalized phosphonium polysulfone hydroxide.

Abstract: Oxygen reduction catalysts for fuel cells are provided. The catalyst can be based on platinum-coated palladium nanotubes, or multiple twinned, crystalline silver nanowires. Also provided is a method of removing carbon dioxide using a membrane having basic functional groups, and a method of water electrolysis using a membrane having basic functional groups.

Abstract: This invention provides a family of functionalized polymers capable of forming membranes having exceptional OH? ionic conductivity as well as advantageous mechanical properties. The invention also provides membranes including the provided polymers and AEMFC/HEMFC fuel cells including such membranes. In a preferred embodiment, preferred function groups include a quaternary phosphonium, and in a more preferred embodiment the provided polymer is (tris(2,4,6-trimethoxyphenyl)phosphine)3 functionalized phosphonium polysulfone hydroxide.

Abstract: This invention provides a family of cation-strung polymers capable of forming membranes having exceptional hydroxide ionic conductivity as well as low water uptake and methods of making the same. The invention also provides for using these cation-strung polymers to manufacture membranes useful in HEMFC fuel cells and other devices such as electrolysis, solar hydrogen generation, redox flow battery, dialysis, reverse osmosis, forward osmosis, pervaporation, ion exchange, sensor, and gas separation.