Abstract: An aspect of the present disclosure relates to radiating light on to a front surface of a glass pane comprising a first surface and a second surface defining a thickness between the first surface and the second surface, wherein the first surface is substantially parallel to the second surface; detecting a transmittance of the light through the glass pane; comparing the transmittance through the glass pane to a reference transmittance value corresponding to a clean reference glass pane; and determining, using the transmittance and the reference transmittance, a soiling metric of a photovoltaic module.

Abstract: An aspect of the present disclosure relates to radiating light on to a front surface of a glass pane comprising a first surface and a second surface defining a thickness between the first surface and the second surface, wherein the first surface is substantially parallel to the second surface; detecting a transmittance of the light through the glass pane; comparing the transmittance through the glass pane to a reference transmittance value corresponding to a clean reference glass pane; and determining, using the transmittance and the reference transmittance, a soiling metric of a photovoltaic module.

Abstract: A hybrid power system is disclosed. The hybrid power system may include a primary power source configured to provide a primary power, and an energy storage device coupled to the primary power source, the energy storage device configured to store excess primary power provided by the primary power source. The hybrid power system may further include a variable speed genset, the variable speed genset including a secondary power source configured to operate at a variable rotor speed to provide a secondary power responsive to power requirements of a load. The hybrid power system may also include a central controller communicatively coupled to the primary power source, the energy storage device, and the variable speed genset, the central controller configured to control the primary power source, the energy storage device, and the variable speed genset based on the power requirements of the load.

Abstract: A hybrid power system is disclosed. The hybrid power system may include a primary power source configured to provide a primary power, and an energy storage device coupled to the primary power source, the energy storage device configured to store excess primary power provided by the primary power source. The hybrid power system may further include a variable speed genset, the variable speed genset including a secondary power source configured to operate at a variable rotor speed to provide a secondary power responsive to power requirements of a load. The hybrid power system may also include a central controller communicatively coupled to the primary power source, the energy storage device, and the variable speed genset, the central controller configured to control the primary power source, the energy storage device, and the variable speed genset based on the power requirements of the load.

Abstract: A valve includes a housing with a first port and a second port. The valve may also include a first valve member operable to meter fluid flow between the first port and the second port. Additionally, the valve may include valve controls operable to control the position of the first valve member at least partially with fluid supplied to a control chamber. The valve controls may include one or more additional valve members operable to meter fluid flow to the control chamber and also fluid flow from the control chamber. The one or more additional valve members may include a pilot poppet operable to meter fluid flow from the control chamber. The valve controls may be operable to control the position of at least one of the one or more additional valve members at least partially as a function of the position of the first valve member.