Thermopile pyranometers exhibit IR radiative losses that affect global and diffuse shortwave measurements made with first class thermopile based instruments. Pyrgeometers can be used to measure the sky temperature and are used to calculate the pyranometer’s IR radiative losses. Few solar monitoring sites are equipped with pyrgeometers necessary to account for the IR radiative losses associated ...

in this study, estimation of global and diffuse solar radiations of selected cities in nigeria was carried out to assess the feasibility of solar energy utilization. the results of this work show the variation of direct and diffuse component of solar radiation in summer and winter months. the contribution of diffuse solar radiation is high during the monsoon months whereas sky conditions are cl...

passive solar systems such as solar chimneys need solar radiation in order to work. therefore, they cannot present stable natural ventilation when solar energy vanishes: to have a more robust and stable condition, solar energy should be stored during the day and released back during the night. phase change materials can save additional thermal energy during the day and release it during the nig...

Since the 1970s, splitting water using solar energy has been a focus of great attention as a possible means for converting solar energy to chemical energy in the form of clean and renewable hydrogen fuel. Approaches to solar water splitting include photocatalytic water splitting with homogeneous or heterogeneous photocatalysts, photoelectrochemical or photoelectrocatalytic (PEC) water splitting...

Diffuse downward shortwave irradiance at the surface arises from the scattering of radiation by molecules and aerosol particles. Recently, we reported that pyranometer-measured diffuse solar irradiance in cloud-free atmospheres is overestimated by radiative transfer models at two low-altitude sites by an amount that exceeds modeling and measurement uncertainties but is correctly estimated withi...

The Fermi paradox highlights the dichotomy between the lack of physical contact with other civilizations and the expectation that technological civilizations are assumed likely to evolve in many locations in the Milky Way galaxy, given the large number of planetary systems within this galaxy. Work by Landis and others has modeled this question in terms of percolation theory and cellular automat...

in the present work, a prototype of a new type of solar collectors, which called direct absorption solar collector, was built and its thermal performance is experimentally compared with conventional flat plate solar collector under transient and steady state conditions. different volume fractions of multi wall carbon nanotubes in water and ethylene glycol mixture (70%:30% in volume) were used a...

Daily sunshine duration is commonly reported at weather stations. Beyond the basic duration report, more information is available from scorched cards of Campbell-Stokes sunshine recorders, such as the estimation of direct-beam solar irradiance. Sunshine cards therefore potentially provide information on sky state, as inferred from solar-radiation data. Some sites have been operational since the...

Sun-synchronous robotic exploration is accomplished by reasoning about sunlight: where the Sun is in the sky, where and when shadows will fall, and how much power can be obtained through various courses of action. We conducted experiments in the Canadian high arctic using a solar-powered rover to prove the concept of Sun-synchronous exploration. Using knowledge of orbital mechanics, local terra...

DATA-CHASER consists of two synergetic projects, DATA and CHASER, which will y as a Hitch-hiker payload aboard the Space Shuttle in 1997. A technology experiment, DATA (Distribution and Automation Technology Advancement) seeks to advance human support technology. CHASER (Col-orado Hitchhiker and Student Experiment of Solar Radiation) is a solar science experiment that serves to test DATA. The D...