Abstract: Paint formulations having a high absorptivity with respect to solar radiation are disclosed herein. The disclosed paint formulations are also thermally and mechanically durable, thereby enabling the paint formulations to be used on components in solar thermal applications where exposure to high temperatures and environmental conditions may be an issue. The paint formulation can include an oxide-based pigment, an organic binder, one or more additives, an inorganic filler, and/or an organic solvent. The pigment can have a relatively high absorptivity with respect to light having a wavelength in the range from 250 nm to 3000 nm. Curing of the paint formulation can irreversibly convert the organic binder into an inorganic binder.

Abstract: Steam can be generated using insolation by a solar collection system. A thermal storage system can store enthalpy in insolation-generated steam at times and can generate steam from stored enthalpy at other times. During some operating periods, a gas-fired superheater can further heat the generated steam to provide superheated steam to generate electricity. Steam at a substantially uniform electricity generating temperature may be produced selectively and at different operating periods from insolation only, from insolation and gas firing, from transfer of enthalpy from a thermal storage system and gas firing, or from a combination of insolation, stored enthalpy transfer, and gas firing. Operating periods can be characterized by at least one of an insolation level, a time of day, or a stage in the operation process. The generated steam can be used in the production of electricity.

Abstract: A method of detecting anomalies in an industrial control system includes analyzing data of correct operational parameters from at least one input device and storing the correct operational parameter or a correlation of at least two operational parameters as training data. The training data is used to train an anomaly detection system. Current operational parameters of the at least one input device are detected. The anomaly detection system then checks at least one of the detected operational parameter or a correlation of at least two detected operational parameters to detect a deviation from the training data. When the detected deviation is above or below a defined threshold, a communication function is performed. For example, the communication function is at least one of creating an alarm, communicating data to at least one of a control system and an operator, and recording the data or the alarm.

Abstract: In a startup period for a solar thermal electricity generating system, a non-solar source of steam heats a downstream receiver (for example, a superheating receiver) prior to insolation being available. Insolation, once available, heats an upstream receiver (for example, an evaporator). The upstream receiver can be arranged in a recirculation loop with a steam separation drum, which may be bypassed during the initial heating of the upstream receiver by insolation. Once sufficient temperature and pressure have been reached, steam from the upstream receiver is directed to the downstream receiver by way of the steam separation drum to replace the non-solar source of steam. Heating of the downstream receiver using steam from the upstream receiver continues until a threshold temperature and pressure are reached. Insolation is then directed at both the upstream and downstream receivers to generate steam for electricity production by a turbine.

Abstract: A solar energy collection system can include a plurality of heliostats configured to reflect sunlight to a target mounted on a tower. Each of the heliostats can have a heliostat controller configured to control a respective heliostat so that the sunlight reflected therefrom is directed to at least one of a plurality of cameras. The cameras can be oriented to image the heliostat. A second controller can be configured to compute geometry data that defines a geometry of the surface of the heliostat from captured images thereof. The geometry data can designate a plurality of subsections of the surface. The computing by the second controller can include storing data indicating sections of the captured images corresponding to the plurality of subsections of the heliostat. The second controller can also calculate data indicating respective surface normals of each of said subsections of each of said heliostat.

Abstract: Images representative of cloud shadows with respect to a field of heliostats can be used to adjust operation of a solar energy system. For example, images of a field of heliostats and shadows produced by the clouds can be obtained. Additionally or alternatively, images of the sky and clouds can be obtained. The images can be analyzed to determine a shading parameter. Based on the shading parameter, an operating parameter of the solar energy system can be changed or maintained. For example, the operating parameter may include aiming directions for one or more of the heliostats. Cloud characteristics in addition to the location of the cloud shadow can be used in determining the shading parameter. Such characteristics can be used in determining if and/or how to change the operating parameter of the solar energy system.

Abstract: Embodiments relate to methods and systems of controlling and operating a wirelessly controlled solar field. By placing a higher density of access points in regions close to the solar field border, communication interference may be mitigated. A method of mitigating interference between an access point and a heliostat in a wireless communication system located in a solar field, may include in a first section of the solar field, deploying a first plurality of access points such that each of the access points is a first distance from its neighbor; and in a second section of the solar field, deploying a second plurality of access points such that each of the access points is a second distance from its neighbor. The first distance is greater than the second distance and the second section of the solar field may be closer to a perimeter of the solar field.

Abstract: A solar energy thermal storage system can include a receiver in which a first storage medium is heated by insolation. First and second thermal storage reservoirs for a second storage medium can be provided. A first heat exchanger can be configured to transfer heat in the first storage medium to the second storage medium. A buffer tank can be located at a height above the receiver and can be fluidically connected to the first heat exchanger at its inlet and the receiver at its outlet. A second heat exchanger can be configured to transfer heat between the second storage medium and pressurized water and/or steam. The use of a buffer tank in conjunction with the first storage medium increases the overall efficiency of the system and results in a higher temperature for the thermal storage system, which can be used to generate superheated steam.

Abstract: Thermal energy can be stored in a fluid-based thermal storage system for later use. The stored thermal energy may be derived from steam generated using insolation in a steam-based solar power system. The thermal storage system can store energy when insolation is generally available. Alternatively or additionally, the thermal energy may be derived from electricity from the electrical grid. For example, the thermal energy can store energy when the electrical grid has excess electricity available for storage. At a later time, the energy stored in the thermal storage system can be released to heat pressurized water or steam in addition to or in place of steam generated by the insolation. For example, the stored thermal energy may be used in preheating the solar power system during startup, in supplementing steam output of the solar power system, or to replace steam generation during low insolation periods.

Abstract: The disclosed subject matter relates to methods and systems for operating a solar steam system in response to a detected or predicted reduced insolation condition (for example, sunset or a cloud condition). In some embodiments, for a period of time, enthalpy stored within a solid material of a conduit via which steam travels en route to a steam turbine is used to heat the steam to drive the turbine. In some embodiments, a net migration of heliostats away from the steam superheater is carried out in response to the detected or predicted reduced insolation condition.

Abstract: A solar energy collection system can include a plurality of heliostats configured to reflect sunlight to a target mounted on a tower. Each of the heliostats can include (i) a mirror assembly, which can include at least one mirror, at least one support arm and a pair of diagonals attached to each end of the support arm, the support arm attached to the backside of the mirror along its entire length, (ii) an elongated central support element, (iii) at least one connecting element configured to attach the mirror assembly to the elongated central support element. The location of attachment points on the at least one connecting element can define the curvature of the mirror in at least one dimension.

Abstract: Systems and methods for directly monitoring energy flux of a solar receiver in a solar energy-based power generation system include measuring infrared radiation emanating from the solar receiver. Such measurement can be achieved using one or more infrared thermography detectors, such as an IR camera. Resulting thermal data obtained by the imaging can be used to determine energy flux distribution on the receiver. A user or a system controller can use the determined flux distribution to adjust heliostat aiming to achieve a desired operation condition. For example, heliostats can be adjusted to achieve a uniform energy flux distribution across the external surface of the receiver and/or to maximize heat transfer to a fluid flowing through the receiver within system operating limits.

Abstract: A paint formulation can include an inorganic oxide-based pigment and an organic binder. The organic binder can be irreversibly converted to an inorganic binder upon curing of the paint formulation at a temperature greater than 200° C. The oxide-based pigment and/or the paint formulation itself can have an absorptivity of at least 80% with respect to the AM 1.5 spectrum. The paint formulation can also include at least one organic solvent, an inorganic filler, and/or at least one additive. Such paint formulations may be stable at high temperatures (e.g., 750° C.) and can be used as solar-radiation-absorbing heat-resistant coatings for components of a solar tower system.

Abstract: Steam can be generated using insolation by a solar collection system. A thermal storage system can store enthalpy in insolation-generated steam at times and can generate steam from stored enthalpy at other times. During some operating periods, a gas-fired superheater can further heat the generated steam to provide superheated steam to generate electricity. Steam at a substantially uniform electricity generating temperature may be produced selectively and at different operating periods from insolation only, from insolation and gas firing, from transfer of enthalpy from a thermal storage system and gas firing, or from a combination of insolation, stored enthalpy transfer, and gas firing. Operating periods can be characterized by at least one of an insolation level, a time of day, or a stage in the operation process. The generated steam can be used in the production of electricity.

Abstract: Adherence to flux or resultant measurable parameter limits, ranges, or patterns can be achieved by directing heliostat mounted mirrors to focus on aiming points designated on the surface of a solar receiver. Different heliostats can be directed to different aiming points, and a heliostat can be directed to different aiming points at different times. The cumulative flux distribution resulting from directing a plurality of heliostats to any aiming point on a receiver surface can be predicted by using statistical methods to calculate the expected beam projection for each individual heliostat or alternatively for a group of heliostats. Control of the heliostats in a solar power system can include designating aiming points on a receiver from time to time and assigning heliostats to aiming points from time to time in accordance with an optimization goal.

Abstract: Embodiments relate to methods and systems of controlling and operating a wirelessly controlled solar field. By placing a higher density of access points in regions close to the solar field border, communication interference may be mitigated. A method of mitigating interference between an access point and a heliostat in a wireless communication system located in a solar field, may include in a first section of the solar field, deploying a first plurality of access points such that each of the access points is a first distance from its neighbor; and in a second section of the solar field, deploying a second plurality of access points such that each of the access points is a second distance from its neighbor. The first distance is greater than the second distance and the second section of the solar field may be closer to a perimeter of the solar field.

Abstract: Paint formulations having a high absorptivity with respect to solar radiation are disclosed herein. The disclosed paint formulations are also thermally and mechanically durable, thereby enabling the paint formulations to be used on components in solar thermal applications where exposure to high temperatures and environmental conditions may be an issue. The paint formulation can include an oxide-based pigment, an organic binder, one or more additives, an inorganic filler, and/or an organic solvent. The pigment can have a relatively high absorptivity with respect to light having a wavelength in the range from 250 nm to 3000 nm. Curing of the paint formulation can irreversibly convert the organic binder into an inorganic binder.

Abstract: Shading by clouds can affect the amount of flux on a heliostat which in turn can affect the energy generated by the solar device. Real-time monitoring of cloud shading of at least a portion of the solar field can allow for more efficient operation of the entire solar power system. For example, diffuse solar radiation and global horizontal radiation may be measured in certain parts of the field in order to estimate the direct normal radiation at any point in the solar field. A cloud map generated based on an image taken of the cloud may be used in calculating the direct normal radiation. By knowing the amount of direct normal radiation at any point in the solar field, the solar energy system can be changed or maintained. For example, the operating parameter may include aiming directions for one or more of the heliostats.

Abstract: Methods, apparatus and systems for operating a solar steam system in response to a detected or predicted reduced or impending reduced insolation event are disclosed herein. Examples of transient reduced insolation events include but are not limited to cloud-induced reduction in insolation, dust-induced reduction in insolation, and insolation events caused by solar eclipses. In some embodiments, in response to the detecting or predicting, steam flow is regulated within the solar steam system to reduce a flow rate into a steam turbine. Alternatively or additionally, one or more heliostats may be responsively redirected onto a steam superheater or steam re-heater.

Abstract: Methods, apparatus and systems for operating a solar steam system in response to a detected or predicted reduced or impending reduced insolation event are disclosed herein. Examples of transient reduced insolation events include but are not limited to cloud-induced reduction in insolation, dust-induced reduction in insolation, and insolation events caused by solar eclipses. In some embodiments, in response to the detecting or predicting, steam flow is regulated within the solar steam system to reduce a flow rate into a steam turbine. Alternatively or additionally, one or more heliostats may be responsively redirected onto a steam superheater or steam re-heater.