The thermodynamic dissipations in crystalline silicon solar cells are identified and evaluated. The ratio of the exergy of the output electrical power to the exergy of the input solar radiation is the effectiveness of the solar cell. The input exergy is converted to the output exergy (the electrical power delivered) with a series of dissipations. These dissipations are identified and evaluated for crystalline silicon cells in terms of the thickness and certain fundamental properties of the light absorbing silicon semiconductor (in this case a P -type material). It is assumed that the N -type material is very thin and absorbs no radiation. For representative values of these properties and a range of thicknesses, it is found that the dissipations due to transmission and thermalization and in the photogeneration process are dominant. The dissipations due to the dark current and recombination are small.

The Compressed Air Energy Storage (CAES) concept is analyzed as an exergy storage concept. A thermodynamic analysis involving the application of the first and second laws of thermodynamics to both the charge and discharge processes is made. Works, heats, cavern energy changes, cavern exergy changes, and dissipations are evaluated for two designs—one idealized and the other more practical. An appropriate effectiveness based on the exergy concept is defined and evaluated.

The controversy over the proper expression for the theoretical maximum conversion efficiency of solar devices is resolved. The correct expression, η max = 1 −4/3 (T o /T s ), relates to the maximum work that can be done by a device which accepts blackbody radiation at T s and rejects heat to the ambient at T o . A general bilinear dissipation equation for solar devices is derived. The effect of back-radiation is considered, and the efficiency decrease due to atmospheric scattering is determined.

A theoretical analysis is given for squeeze film bearings which use an electrically conducting fluid, such as a liquid metal, as the lubricant and which are in the presence of a magnetic field. Electrical energy is added to the film by an exterior source. By considering infinitely long rectangular plates, the fluid film thickness is determined as a function of time, with the applied magnetic and electric fields as parameters. It is shown that the squeeze action is altered significantly when the electric field is symmetrical about the center of the bearing, and results are presented for various values of the Hartmann number.

Energy conversion by the mechanism of electrokinetics is investigated. A device capable of converting either electrical power into pumping power or pumping power into electrical power in the steady state is studied. The basic equations coupling voltage, pressure, current and flow rate are established and simplified in the light of existing experimental evidence. Operating characteristics for both the fluid pumping and the electrical generation mode are determined and illustrated by example problems. The results indicate that with water as the working fluid, conversion efficiencies of only 0.392 percent are possible.

A thermally powered pump for fluids which are electrically conducting, which utilizes the Lorentz force between an electric current induced by the Seebeck effect, and an external magnetic field is examined. The pressure rise in the pump is found to be proportional to the magnetic flux density while the flow rate is found to be inversely proportional to the magnetic flux density. Thus the pumping power and efficiency (both being proportional to the product of pressure rise and flow) are independent of the applied magnetic field. Calculations for a pump with constantan walls handling sodium and utilizing a temperature difference of 300 deg C show that a maximum efficiency of close to seven-tenths of a percent is possible. If the same pump is constructed with optimum thickness walls made of the semiconductor AgSbTe 2 , it would have an efficiency of nearly six percent.

It is demonstrated that the form of the energy-dissipation equation which describes thermoelectric and thermomagnetic generators is greatly dependent on the choice of dependent variables in the coupled equations used to describe the devices. If “natural” coordinates are chosen, the energy dissipation will always contain two terms—the Fourier conduction term and Joulean heating term. If “unnatural” coordinates are chosen, the energy-dissipation equation will contain three terms. A brief solid-state consideration demonstrates how a bound on the figure-of-merit temperature product can arise in terms of fundamental physical parameters.

The development of free convection in a viscous fluid between heated vertical plates is investigated. The basic governing continuity, momentum, and energy equations are expressed in finite difference form and solved numerically on a digital computer. Results are obtained for the variations of velocity, temperature, and pressure throughout the flow field assuming the fluid to enter the channel with ambient temperature and a flat velocity profile. The flow and heat-transfer characteristics of the channel are studied and a development height established. A comparison is made between the results of this theoretical investigation and the experimental work of Elenbaas.