## The chimney

A chimney relies on an energy source to heat air which rises via a buoy­ancy effect. The analysis is relatively simple and requires use of the Bernoulli equation which comes from the fluid mechanics literature. The Bernoulli equation is valid along the path that a fluid (in our case Solar Energy, An Introduction, First Edition, […]

## The solar chimney and tower

The Sun can supply radiation to a photovoltaic device, as described in the previous chapter, to provide electricity for residential or indus­trial use. This technology is quite effective and useful. Here, heating of air with solar radiation in a chimney is initially considered to draw it through a building for a cooling effect. This is […]

## Parameters for an operating photovoltaic device

So far non-idealities have not been considered except with recombina­tion occurring in the quasi-neutral regions through eqns (6.15). However, there can be defects in the crystalline lattice and this can cause recom­bination in the depletion region. The result of the calculation can be found in most solar photovoltaic textbooks, the key fact to remember is […]

## Current-voltage relation

Before discussing the current-voltage relation, a discussion is given to clarify why a photovoltaic device is operated under forward bias again, knowing the details discussed above. At first forward bias operation seems contradictory; reference to Fig. 6.8 shows that when the excited electron is formed in the n-doped region the resulting hole is swept over […]

## Details of what happens in a photovoltaic device

In the previous section we described in words what happens in a pho­tovoltaic device, while here we present the details. The key aspect of the solar cell is development of the depletion region and the internal potential. To understand how this potential forms we must first deter­mine what happens to the chemical potential in the […]

## What happens inside a photovoltaic device?

The similarity between a Carnot heat engine and a photovoltaic device was discussed in Chapter 3. The heat engine is fictitious while a photo­voltaic device is not. In this case heat or radiation from the Sun is absorbed by the material making up the cell through excitation of an electron from its ground state to […]

## The photovoltaic device

A brief introduction to the physics dictating how a photovoltaic device or solar cell works is presented. This is truly a cursory introduction as we skirt around the details of semiconductor physics, yet, is a required exercise. The reader can then appreciate that a typical photovoltaic device is made from a p-n junction, defined below, […]

## Generation of heat

Heat generation comes about by the material absorbing radiation for use in solar thermal applications. In this case, rather than producing electricity as would occur in a photovoltaic device, the electron and hole recombine to form heat. Heat is produced by the electrons losing energy to the surrounding crystalline matrix by inducing lattice vibrations to […]