Solar radiation renewable energy

An ideal renewable resource will be one that can be replenished over a relatively short timescale or is essentially limitless in supply. The latter will include solar radiation, geothermal energy, oxygen, carbon dioxide and water. Nor should production or consumption of these resources contribute to the net atmospheric burden of carbon dioxide. Advantage can be taken of the fixation of atmospheric carbon dioxide into plant material by the process of photosynthesis. 

Marion, W., and Wilcox, S. (1994). Solar Radiation Data Manual for Elat-Plate and Concentrating Collectors. Golden, CO National Renewable Energy Laboratory . National Renewable energy Laboratoiy (NREL) Home Page. National Renewable Energy Laboratoiy. August 9, 2000 < http /Avww.nrel.gov/>. 

The ocean thermal energy conversion (OTEC) is an energy technology that converts solar radiation to electric power. OTEC systems use the ocean s natural thermal gradient to drive a power-prodncing cycle. As long as the temperature between the warm strrface water and the cold deep water differs by about 20 K, an OTEC system can produce a significant amormt of power. The oceans are thus a vast renewable resomce, with the potential to help tts produce billions of watts of electric power. 

Labed S., Lorenzo E., The impact of solar radiation variability and data discrepancies on the design of PV systems. Renewable Energy 2004 29 1007-1022. 

Machine vision will be an important tool in the operation of unattended, fully automated renewable energy processes. Vision is the response of the eye and brain to light. Machine vision is the artificial response of a device to spectral radiation. Machine vision also extends the human range of the visible spectrum into the IR, UV, and x-ray regions. Machine vision can be used to make decisions faster or more accurately and precisely than a human can. Machine vision may combine online defect monitors with shade monitoring, which will be an important tool in optimizing the positioning of solar collectors (Table 3.128). 

In several renewable energy processes, including the concentrating solar collectors, boilers, and combustion systems, the accurate measurement and control of high temperatures are required. These (over 1,000°C) temperatures are most often detected by thermocouples (types B, C, R, and S) and by optical and IR-radiation pyrometers. These devices are only briefly mentioned here, because they will be discussed in detail later. Here, the emphasis will be on some of the other high-temperature detectors such as sonic and ultrasonic sensors. 

Knowledge of the optical properties of materials in relation to the solar spectrum is also important in measuring broadband solar radiation. For instance, a pyranome ter used to monitor total solar radiation for a renewable energy system has a spectral response (due to the special glass dome protecting the detector) that does not respond to the thermal infrared radiation of the sky beyond 3000 nm, as shown in Fig. 15. Flowever, there will be thermal infrared radiation exchanged between the radiometer and the sky dome, which will influence the measurement performance of the pyranometer.9... 

Fig. 6. Map of average U.S. insolation levels on a flat surface, tilted south at an angle equal to the site s latitude. The 250-290 W/m2 range in insolation levels for the sensitivity analysis corresponds to solar radiation levels of 6-7 kWh/m2/day. This map was developed from the Climatological Solar Radiation (CSR) Model, developed by the National Renewable Energy Laboratory for the U.S. Department of Energy.

W. Marion and S. Wilcox, Solar Radiation Data Manual for Flat-Plate and Concentrating Collectors, Manual Produced by the National Renewable Energy Laboratory s Analytic Studies Division. Contract No. NREL/TP-463-5607, DE93018229, April, 1994. 

Diamond et al. [127] have estimated UVR doses in wetlands using this approach. Typical UVR doses were estimated by first generating maximal solar radiation doses for each day using a radiative transfer model, SBDART [113]. The model produced values for the full spectrum of solar radiation, from 280 to 700 nm, for cloudless conditions. These maximal values were then modified based on cloud cover effect estimates from 30 yr of historical solar radiation data (National Renewable Energy Laboratory, Department of Energy http //rredc.nrel.gov/solar/). The values derived in this procedure were estimated daily terrestrial, spectral (2 nm increments from 280 to 700 nm) solar radiation doses. Water column doses were then derived from absorption coefficients and spectral attenuation data described by Peterson et al. [128]. Although the focus of this effort was to characterize risk of UV-B radiation effects in amphibians, the procedure is directly applicable to phototoxicity, and the resulting UV-A radiation and spectral doses could be directly incorporated into calculation of possible effects. 

National Renewable Energy Laboratory (1992). User s Manual National Solar Radiation Data Base (1961-1990). National Climatic Data Center, Asheville, NC. 

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