The thermal analysis of collector storage walls is presented in Section 6.2.1, Chapter 6, where a diagram of the wall and the thermal gains and losses are given. The unutilizability concept, developed by Monsen et al. (1982), can also be applied in this case to determine the auxiliary energy required to cover the energy supplied […]

Due to the nature of the economic analysis, i. e., predicting the way various costs will occur during the life of a solar energy system, a number of uncertainties are involved in the method. The person responsible for the economic analysis of a solar energy system must consider a number of economic parameters and how […]

As we have already seen in solar energy system design, the collector area is considered as the primary parameter for a given load and system configuration. The collector area is also the optimization parameter, i. e., the designer seeks to find the collector area that gives the highest life cycle savings. A method for the […]

Another way of viewing the calculations of Example 12.7 is to obtain the pres­ent worth of each column and sum them to obtain the present worth of solar savings, using appropriate signs for each column. Therefore, the life cycle sav­ings (LCS) of a solar energy system over a conventional system is expressed as the difference […]

When a solar energy system is designed, the engineer seeks to find a solution that gives the maximum life cycle savings of the installation. Such savings rep­resent the money that the user/owner will save because of the use of a solar energy system instead of buying fuel. To find the optimum size system that gives […]

The example in this section considers a complete solar water heating system. Although different solar energy systems have different details, the way of han­dling the problems is the same. Example 12.7 A combined solar and auxiliary energy system is used to meet the same load as in Example 12.5. The total cost of the system […]

The first example is about the fuel cost of a non-solar or conventional energy system. It examines the time value of an inflating fuel cost. Example 12.5 Calculate the cost of fuel of a conventional (non-solar) energy system for 15 years if the total annual load is 114.9 GJ and the fuel rate is $17.2/GJ, […]

In life cycle cost analysis, all anticipated costs are discounted to their present worth and the life cycle cost is the addition of all present worth values. The cash flow for each year can be calculated, and the life cycle cost can be found by discounting each annual cash flow to its present value and […]