Abstract:
An offshore vessel embodies a mobile buoyant energy recovery system enabled to extract energy from solar power. An exemplary energy recovery system comprises concentrating solar thermal power systems (CSP) or concentrating photovoltaic power (CPV) systems on the deck of the vessel. Within the vessel hull, ballast water serves multiple purposes. The ballast not only stabilizes the vessel, but also provides reactant for hydrogen electrolysis or ammonia synthesis, or steam for a turbine. For CPV systems the ballast conducts heat as a coolant improving the efficiency and durability of photovoltaic cells. For CSP systems the ballast water becomes superheated steam through a primary heat exchanger in the concentrator. In some embodiments, some steam from the CSP primary heat exchanger or from the CPV coolant system undergoes high-pressure electrolysis of enhanced efficiency due to its high temperature. In some embodiments, the remaining steam that did not undergo electrolysis drives a steam turbine providing electrical current for electrolysis. A secondary heat exchanger takes heat from the steam expelled from an energy storage process to efficiently distill ballast water at a lower temperature thus minimizing corrosion and build-up of scale. A remote control Supervisory Control and Data Acquisition System (SCADA) determines position, navigation, configuration, and operation of the preferably unmanned modular mobile buoyant energy recovery structure based on Geospatial Information Systems (GIS), Velocity Performance Prediction (VPP) models, Global Positioning Satellites (GPS) and various onboard sensors and controls.
Abstract:
A computer to improve prediction of solar output for a solar power system that includes a processor and a memory. The memory has software code which when executed causes the computer to receive power output data from the solar power system, calculate a statistical mean of the power output data, receive solar hour information from an almanac system and generate an almanac predicted power output for the solar power system for the specified time period. The computer receives weather information for the specified time period from a weather predicting source and calculates a weather prediction-to-solar almanac ratio based on a comparison of the solar hour information to the weather information. The computer generates a predicted power output for the specified time period by multiplying the almanac predicted power output for the solar power system by the weather prediction-to-solar almanac ratio and stores the predicted power output for the specified time period.
Abstract:
A suntracking system for a central receiver solar power plant includes a heliostat field for reflecting sunlight to a receiver, cameras directed toward at least a subset of the heliostats, and a controller. The cameras are configured to produce images of sunlight reflected from multiple heliostats. The heliostats include a mirrored surface having a settable orientation and have a geometry modeled by a set of parameters. A method of estimating heliostat parameters for open-loop suntracking includes acquiring pointing samples by setting the direction of reflection of the heliostats and detecting concurrent sunlight reflections into the cameras. The method uses the acquired pointing samples and surveyed locations of the cameras to estimate the heliostat parameters. The method accurately maintains the sun's reflection directed toward the receiver open-loop utilizing the estimated tracking parameters.
Abstract:
A suntracking system for a central receiver solar power plant includes a heliostat field for reflecting sunlight to a receiver, cameras directed toward at least a subset of the heliostats, and a controller. The cameras are configured to produce images of sunlight reflected from multiple heliostats. The heliostats include a mirrored surface having a settable orientation and have a geometry modeled by a set of parameters. A method of estimating heliostat parameters for open-loop suntracking includes acquiring pointing samples by setting the direction of reflection of the heliostats and detecting concurrent sunlight reflections into the cameras. The method uses the acquired pointing samples and surveyed locations of the cameras to estimate the heliostat parameters. The method accurately maintains the sun's reflection directed toward the receiver open-loop utilizing the estimated tracking parameters.
Abstract:
A photovoltaic efficiency estimator, comprising a photovoltaic cell covered by a sunlight-penetrable surface; an illuminator for artificially illuminating said surface; and a controller connected to said photovoltaic cell and to said illuminator, said controller being configured to measure an amount of voltage produced in said photovoltaic cell as a result of the artificial illumination by said illuminator, so as to estimate a decrease in the efficiency of said photovoltaic cell caused by dirt on said surface.
Abstract:
An optical concentrator is disclosed which includes an imaging, aplanatic optical element having a front surface with a one-way light admitting portion, a back surface with a reflective portion, and an interior region of refractive material disposed between the front and backs surfaces.
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:
A method for generating temporal solar irradiance values for a selected area. Binary format hillshade files are generated for selected azimuth and altitude points on the Sun's path for selected time points for the area. Data in the hillshade files is reclassified into reclassified files, on basis of the selected time points relative to the solar radiation data. The reclassified files are then summed to generate a set of normalized reclassified files, each representing a selected intermediate interval. The values for each corresponding one of the cells in the set of normalized reclassified files are summed to generate an irradiance-weighted shade file. The hillshade files are summed by inclusively OR-ing corresponding values for each of the cells in each of the hillshade files to generate respective composite files for each said selected intermediate interval. The composite files are then summed to generate a summed shade/time frequency file in which each data point therein represents the frequency of repetition of corresponding cells in the hillshade files over a selected upper interval of time. Each data point value in the irradiance-weighted shade file is then divided by the corresponding data point value in the frequency file to generate a file having solar access values for the upper interval, relative to the intermediate interval, for the selected area.
Abstract:
Method for using renewable energy sources comprising at least one remote energy generation plant which may be operated by a renewable energy source, a production measurement unit at the location of the at least one remote energy generation plant which measures the production of the at least one remote energy generation plant, a central control unit, the method comprising the following steps: a) producing a production forecast for the production of the at least one remote energy generation plant in a future time period, b) transmitting the production forecast to the central control unit via a computer network, c) operating the remote energy generation plant and measuring the production using the production measurement unit, d) comparing the measured production with the production forecast, e) notifying an operator of the at least one energy generation plant, if the measured production deviates from the production forecast beyond a predetermined level.
Abstract:
A computer which functions by a performance prediction program for a ground source heat pump system of the present invention and a performance prediction system constructed thereby include a dimensionless distance calculating means, a first dimensionless time calculating means, a second dimensionless time calculating means, a boundary time acquiring means, an underground temperature change calculating means, and a tube surface temperature change calculating means. The performance prediction program and performance prediction system can be applied to the design of heat exchange system by obtaining predicted underground temperature data for the ground source heat pump system with high accuracy and predicting the performance for the ground source heat pump system based on the resulting underground temperature changes, etc., in view of the use of a plurality of buried tubes, underground temperature change patterns for buried tubes placed at different intervals, and the use of U-shaped tube heat exchangers.