Virtually every home has at least one fridge running 24/7.
So after heating water, which consumes a lot of energy, fridges are one of the other major consumers of electricity in many homes.
Domestic fridges, especially extravagant modern double door designs usually have large doors that open sideways. This makes them very convenient to use. But every time you open that large door, all the cold air inside the fridge literally falls out onto the floor at your feet and is replaced with warm air. This is very inefficient with regards to energy consumption, especially when one thinks of how often the fridge gets opened each day.
A far better design from an energy efficiency point of view is the chest type configuration which keeps the cold air in place when you open the lid. But chest designs are far less convenient to use on an everyday basis because you have to bend over to reach the stuff inside. In addition, the goods inside need to be stacked on top of each other, which makes it difficult to easily reach, or even find, stuff placed at the bottom.
However, the latest fridges have far more efficient cooling systems which reduce their energy consumption significantly in comparison to older designs. Most new fridges have an energy rating tag which shows how much energy they consumed in a standard test extrapolated over a year. The improvement in efficiency is quite dramatic in some cases, so it may well pay to replace an old fridge with a new more efficient version in many homes!
An example of this is the fridge we tested a few years ago (Defy Arctica), which was quite a modern medium sized fridge at the time of testing. Our results showed an energy consumption of 2.47 kWh per day. The same size and style of fridge currently available uses just less than 1 kWh a day, according to the energy consumption tags on display. At current electricity rates, that amounts to a saving of R53 odd a month. This means a new more efficient fridge could pay for itself in 3-4 years.