System description, categorization, and comparison

This chapter presents possible ways to analyze and categorize existing and even future solar and heat pump (SHP) systems. There are five main criteria to describe a solar and heat pump system: the type of heat demand to be served; the low-temperature heat source(s) of the heat pump; the form(s) of energy used to drive the system; the function and placement of storages in the system; and the interactions between these components. The chapter introduces a graphical representation to systematically analyze and compare solar and heat pump systems. It presents statistical analysis of market-available solar thermal and heat pump systems. The chapter deals with the question to what extent SHP already penetrated the market. Results can be stated either in absolute numbers or relative to conventional systems, that is, non-solar and heat pump systems. Here, it is evident that the industry follows theoretical considerations in both ecology and economy.