With so many options for water heating, the inevitable question is: which is best?
Like most things in life, the answer depends on your priorities and circumstances. Things like location & climate, size of household, budget, reliability of electricity supply and importance of environmental considerations all have an impact on the suitability of available water heating options.
However, there are clear advantages to some options over others. Let’s first look at cost.
When considering the cost of any system, it is important to also consider total lifetime cost. This includes the upfront cost of the system and installation (capital cost), as well as any ongoing costs, such as electricity or fuel costs, maintenance and repair costs. One must also consider the lifetime of the system.
There is a methodology to account for all the above factors called Levelized Cost of Energy (LCOE). It calculates the total cost per unit of energy (called a kWh or ‘kilowatt-hour’) for different energy options.
The graph below shows the overall cost or LCOE for several water heating options in South Africa as of 2021 (see tab “Levelized Cost of Energy” at ref):