Storage heaters work by storing heat produced during the night by electric elements in insulating clay bricks. The heat is then released slowly during the daytime to provide constant heating throughout.
The great economic advantage of storage heaters is that they use electricity at night during off-peak periods. Because most electricity suppliers charge higher rates during periods of peak consumption and much lower ones during periods of low consumption, the savings on the use of storage heater might be substantial compared to alternative electrical or gas systems. To calculate savings, contact your electricity supplier to find out about the rate differentials during peak and off-peak periods.
Storage heaters are very simple mechanisms, essentially they are electrical elements surrounded by clay bricks. Because of this, installation and maintenance costs are also often much lower than alternative forms of heating.
Apart from the sheer bulk of a storage heater, which might cause difficulties for installation, the chief disadvantage of the storage heater is lack of flexibility. Because heat is built up overnight, it cannot be simply switched off if the weather turns warm unexpectedly. Likewise, if it turns colder than expected, the only way to turn the heat up is to "charge" the heater during peak hours, which is more expensive.