Introduction. Previous studies of initiation of plate tectonics were concerned mostly with the present-day Earth where plate tectonics is actively occurring [1-3]. Understanding of how plate tectonics starts and can be sustained for a long time on an Earth-like planet is a different problem. Investigation of this problem began only recently [4-6]. This problem is also important for understandin...

The F10.7 index provides a daily record of solar microwave emissions, which vary in rough proportion to the projected area of bright magnetic structures called plages and network, and also sunspots, on the sun's disk. The daily observations used to form the index only began in 1947. Recently, we digitized the archive of daily Ca K spectroheliograms obtained at Mt. Wilson Observatory between 190...

A prototype concentrating photovoltaic (CPV) module was designed and constructed with a low concentrating dielectric compound parabolic concentrator (DiACPC) for outdoor characterisation. The designed concentrator has acceptance half angles of 0 & 55 with a concentration ratio of 2.8. This concentrator design is suitable for building facade integration in higher latitude (>55 ) locations. A sma...

Abstract—Solar water heating is a thermodynamic process of heating water using sunlight with the help of solar water heater. Thus, solar water heater is a device used to harness solar energy. In this paper, a modified solar water heating system (MSWHS) has been proposed over flat plate collector (FPC) and Evacuated tube collector (ETC). The modifications include selection of materials other tha...

This paper introduces the functioning principle as well as dimensioning elements of a new active solar heating system using air as heat carrier. The air is heated in flat-plate collectors and then circulated through the building walls having circulation “hollows”. The heat storage function is performed by a rockbed storage unit. The solar collectors have water-air double service and supply the ...

Recently Debates about Energy and the issue of global warming have led to the use of new energy. One of the best options for this purpose is the use of a new hybrid system of power, heating and refrigeration, with its thermal source of solar and geothermal energy. In the present study, used a combined cooling, heating and power system based on the organic Rankine cycle and the Ejector Refrigera...

Concentrating solar collectors of low concentration ratio can supply hot water or process heat at intermediate temperatures, i.e. 80 to 180 C, where flat plate collectors are not effective, and for which there are a number of industrial, domestic and rural applications. This paper studies the potential applications of this technology and presents case studies to prove its feasibility.