While electrical resistance heating can no longer provide the bulk of your hot water it can be used to supplement supply in areas that are not used often, or where smaller quantities of water are used or in the South African Context where you don’t mind a cold shower. (South Africa experienced power shortages in recent years resulting in planned power outages cleverly marketed as ‘load shedding’).
Standard electric geyser on a timer could be installed in a guest suite that is occupied from time to time. However, in a new dwelling, this cannot supply more than 50% of the hot water required by the household as per the ‘design population’ of the dwelling as set out by SANS10400 XA.
Side note: Eskom’s design population quota is 50 liters of hot water per person per day, the building regulations require 80- 115 liters per person per day, and assume a design population at 2 persons per bedroom, for a domestic dwelling.
Instantaneous electric geysers are now available locally and are ideal for water sources that get used intermittently. They work the same as instantaneous gas geysers in that that heat water instantaneously, as required and do not have a storage tank. They do however use large volumes of electricity when in use, but are ideal for guest suites or bathrooms and applications that are not used daily.
Under counter electric
Under counter electrical geysers may be useful when a guest toilet or outside area prep bowl is far from the main water heating source and a small amount of hot water is required. They hold small quantities of water; therefore they do not use huge amounts of energy to heat the water.
This post is a part of the ‘in hot water ‘series and should not be read in isolation.
Please see my conclusion on this issue of water heating.