Solar Thermal Technology Marketing Summaries

This technology is an automated system in which the reflection of a mirror, typically for solar applications, is characterized by the slope and slope errors. The system uses a video camera and a PC to create fringe patterns from the reflection of the mirror. These patterns can characterize and better assess the quality of the mirrors for solar applications in a more automated process.

With growing numbers of solar energy systems being proposed and installed throughout the United States, the potential impact of glint and glare from photovoltaic modules, concentrating solar collectors, receivers, and other components is receiving increased attention as a potential hazard or distraction for pilots, air-traffic control personnel, motorists, and residents. Hazards from reflection of solar radiation from solar power plants include the potential for permanent eye injury (e.g.,... read more

Current oil and salt based heat transfer fluids have significant limitations such as usable temperature, high cost, and limited thermal conversion efficiency. To achieve the Department of Energy SunShot goal of high efficiency, low cost renewable power generation, a highly efficient and economical way to absorb solar heat and to store the thermal energy is important for broad deployment of concentrating solar power (CSP) plants as baseload power.

Radiative transfer (RT) models simulating broadband solar radiation have been widely used by atmospheric scientists to model solar resources for various energy applications such as operational forecasting. Due to the complexity of solving the RT equation, the computation under cloudy conditions can be extremely time consuming though many approximations (e.g. two-stream approach and delta-M truncation scheme) have been utilized. Thus, a more efficient RT model is crucial for model... read more

Parabolic trough power plants use concentrated solar thermal energy to generate electricity by producing steam that drives a Rankine power cycle. Solar thermal energy is captured in a fluid medium which flows through receiver tubes. At high temperatures the vapor generates hydrogen gas which can leak into the annular volume of the heat collection element. The presence of low partial pressures of hydrogen gas in the annulus significantly decreases the thermal performance of the heat... read more

Concentrating Solar Power (CSP) systems utilize solar energy to drive a thermal power cycle for the generation of electricity. CSP technologies include parabolic trough, linear Fresnel, central receiver or “power tower”, and dish/engine systems. Considerable interest in CSP has been driven by renewable energy portfolio standards applicable to energy providers in the southwestern United States and renewable energy feed-in tariffs in Spain. CSP systems are typically deployed as... read more

Thermophotovoltaic (TPV) devices can be used to generate power from photons, and consist of a thermal emitter and photodiode. These limitations of photovoltatic (PV) devices solar cells—since sunlight is composed of many different wavelengths, not all incident photons have an energy larger than the energy band gap (Eg) of the semiconducting material of the photodiode and thus, not all photons can contribute to the photo-current. If the thermal emitter of a TPV can absorb all incoming... read more

As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. The Distant Observer (DO) tool, developed by engineers at the National Renewable Energy Laboratory (NREL), is a fast and highly accurate tool that provides complete characterization of the performance of the optical components which include the mirror panels and thermal receiver. This tool is very useful for testing both prototype and... read more

Iowa State University and Ames Laboratory researchers have developed a method for increasing the efficiency of conventional incandescent light bulbs.

Ames Laboratory researchers have developed a process for producing more efficient polymer solar cells by increasing light absorption through a thin and uniform light-absorbing layer deposited on a textured substrate. 

There are multiple methods for measuring fluid flow. Current methods rely on different physical principles such as: pressure measurement, particle tracking using images, heat removal from a wire and Doppler shift measurements. However, infrared images are not used to quantitatively measure flow properties, fluid mixing, or mass concentration of fluids.

These existing techniques for measuring two dimensional velocity fields, such as particle image velocimetry (PIV), require expensive and... read more

A recent “Reinvent the Toilet Challenge” put forth by the Bill & Melinda Gates Foundation called for researchers to develop sanitation solutions that are affordable and desirable to use, render fecal waste harmless within a short time-span, are self-contained without the need for flush water or electricity, and produce valuable end products. Current waterless toilets – such as dry pit latrines, ventilated improved pit (VIP) latrines, and composting toilets – fall... read more

There are numerous options for renewable energy systems development. Location, size, type of system, and a number of other criteria need to be considered. The objective of this program is to determine the optimal size (capacity, Kilowatt (kW)) of a renewable energy generator, based on minimizing life cycle cost (LCC).

The reason for developing such a program is driven by three major issues. First, the need to evaluate a very large number (tens of thousands) of project opportunity sites.... read more

In order to increase the speed and scale of Renewable Energy (RE) solar project deployment on buildings, energy savings analysis and a strong business case is required. This software provides an hourly simulation to optimize rooftop area for combined solar photovoltaic (PV) and solar hot water (SHW) systems or solely PV. The program calculates energy savings, demand reduction, cost savings, C02 reduction, and building life cycle costs including: simple payback, discounted payback,... read more

The invention provides processes that perform biomass gasification or pyrolysis for production of hydrogen, synthesis gas, liquid fuels, or other hydrocarbon based chemicals. The methods of the invention use solar thermal energy as the energy source for the biomass pyrolysis or gasification. This allows operation at temperatures above 950 degrees C, speeding up reaction kinetics and shifting thermodynamics to various reaction end products, thus, bypassing the formation of tars and other... read more

Currently most hydrogen is produced through a process of heating natural gas with water vapor called steam reforming. This process requires energy to heat the gasses and produces greenhouse gases such as CO2 as its byproducts. These conditions confine steam reforming to large industrial plants requiring trucks to transport the hydrogen to users, since most population centers have regulations that prohibit such high levels of CO2.

This algorithm calculates the solar and lunar zenith and azimuth angles in the period from the year -2000 to 6000, with uncertainties of +/- 0.0003 degrees for the Sun and +/- 0.003 degrees for the Moon, based on the date, time, and location on Earth.

A University of Colorado research team led by Alan Weimer has developed a technique for a substantially isothermal hercynite cycle, in which the entire reaction cycle is performed isothermally at 1200-1400°C (though the cycle can be performed at temperatures as low as 940°C). Because no significant heating or cooling is required between the respective cycles, the hercynite cycle allows faster, more efficient cycling and less wear on the equipment and materials used for the process.... read more

Parabolic trough collectors are one of the main concentrating solar power (CSP) technologies used in commercial utility-scale power generation plants. A key param­eter for trough performance evaluation is the collector optical efficiency, which is the ratio of the absorbed solar power by the receiver to that intercepted by the collector aperture. This has a direct influence on annual electricity generation, annual plant revenue, and, eventually, the levelized cost of energy (LCOE).

Th... read more

Berkeley Lab scientists Rachel Segalman, Jeffrey Urban and Kevin See have invented a water based process to make thermoelectric films. The resulting composite film displays both the high thermovoltage expected of nanocrystals and the high electrical conductivity of polymers—a beneficial pairing of traits. These traits can counteract in conventional thermoelectric materials to limit a thermoelectric device’s efficiency and economic utility.

Ames Laboratory researchers have developed fabrication methods for a polarized thermal emitter than can be used to create more efficient thermophotovoltaic devices for power generation.

Sandia has developed a heat transfer fluid (HTF) for use at elevated temperatures that has a lower freezing point than any molten salt mixture available commercially. This allows the HTF to be used in applications in which the expensive parasitic energy costs necessary for freeze protection can be significantly reduced. The higher operating temperature limit significantly increases power cycle efficiency and overall power plan sun-to-net electric efficiency.

Sandia has developed a cheap, efficient, and accurate method of measuring the irradiance from solar reflections using a digital camera. Measurements of reflected solar irradiance is of great importance to industry, military, and government agencies to assess potential impacts of glint and glare from growing numbers of solar power installations around the world. In addition, this measurement technique can be used to monitor and maintain system performance for concentrating solar power... read more

This technology is a new technique for parabolic trough mirror alignment based on the use of an innovative Theoretical Overlay Photographic (TOP) approach. It is a variation of current methods used on parabolic dish systems and involves overlay of theoretical images of the Heat Collection Element (HCE) in the mirrors onto carefully surveyed photographic images and adjustment of mirror alignment until they match.

A good HTF must be able to absorb a substantial amount of energy in a given volume, a property known as volumetric heat capacity. Physical properties such as viscosity, thermal stability, and thermal conductivity must also be considered. Ionic liquids (IL) were discovered more than 30 years ago and are organic compounds with negligible vapor pressure. ILs are molten salts with low melting points below 100°C, high liquid range above 400°C, in some cases, freezing points below 0°C.... read more

Ames Laboratory researchers have developed a process for fabrication of solar cells with increased efficiency. 

Buildings consume approximately 40% of the energy, and nearly 70% of the electricity used in the United States. Building surfaces are well suited to renewable energy production. The surface area of a typical residence is large enough to produce the electricity required to operate the building. However, in order to achieve net-zero energy use, solar thermal collectors are often required to produce hot water for domestic and space heating needs or pre-heated ventilation air.
Current problems... read more

Iowa State University and Ames Laboratory researchers have developed fabrication methods for a polarized thermal emitter than can be used to create more efficient thermophotovoltaic devices for power generation.

This algorithm calculates the solar zenith and azimuth angles in the period from the year -2000 to 6000, with uncertainties of +/- 0.0003 degrees based on the date, time, and location on Earth. (Reference: Reda, I.; Andreas, A., Solar Position Algorithm for Solar Radiation Applications, Solar Energy. Vol. 76(5), 2004; pp. 577-589).