On 14/08/2018 10:28, Harry Bloomfield wrote:
Brian Gaff explained on 14/08/2018 :
So how does a slow heater* make any difference. Take the kettle if it
takes longer to boil the water surely you have probably used the same
power as you would have with a more powerful heater for a shorter
time. Same goes for room heaters.

Not quite the same thing. A room heater has to have deliberate loss of
heat to warm the room. If the loss of heat occurs faster than the heat
input, then it will not adequately warm the room.

A storage heater has to have sufficient capacity to gain all the energy
it needs, its charge, within the off-peak hours it is designed for.
Unlikely, but a 300w storage heater would take ten times as long to gain
the same charge as a 3Kw version.

But you only have a few hours from about 1AM to about 7AM to
store sufficient energy to last the day.