That depends on what you mean by ‘economical’. Electric heaters are all 100% efficient, in that every watt of electrical energy they consume is converted into heat for your comfort. It will cost just as much to run a 1kW panel heater like the one you linked to as it would to run a 1kW fan heater or a 1kW infra-red heater. The only difference is how you experience the heat produced.

A convector heater like the Stiebel-Eltron one heats up the air inside it, which comes out of the louvres and rises up towards the ceiling. This produces a flow through the heater - cold air in at the bottom and warm air out at the top. Eventually, depending on how big the room is, the air in it will all be at a similar warm temperature. Fan heaters blow out hot air which can be quite comfortable if you’re in the way of the warm-air stream. Infra-red heaters heat up objects near it - including human bodies - but not so much the air around them. Again, this can be quite comfortable if you’re in front of the heater.

It sounds as if you suffer from a cold bedroom. It’s not just a problem that this can be uncomfortable, but because there’s often high humidity in bedrooms, condensation on walls and windows can lead to other worse problems like a proliferation of mould. It won’t be cheap to combat this, but the heater you linked to may be the best bet. It would have to be running for a long time to make the difference you’d need, e.g. from sunset to sunrise. 

If humidity isn’t a major problem (the room is reasonably well insulated with double-glazed windows), then you might consider a more intimate solution: an electric underblanket on the bed. OK, It might be a bit chilly getting into and out of bed, but the momentary discomfort is soon forgotten. 

Many thanks for the reply.

Our house is very poor insulation and it does get very cold. 

I will try this heater for now.

Thank you again

Hey @froggy8,

I haven’t used one myself but they’re quite popular online! I found a few videos of them searching google/youtube - 

Let us know how it goes if you decide to go with it.

You could try a convector heater like this. This is the same basic technology.

https://www.therange.co.uk/diy/heating/radiators-and-radiator-covers/radiators/2-5kw-digital-oil-free-rad?gad_source=4&gclid=CjwKCAjwx4O4BhAnEiwA42SbVGohLUGrDrMwivw79ARW2zXo0K5Z-LUNJo70SJXP-qfyoM79yeTDdRoCOXcQAvD_BwE#6240349

Then you can set a timer or remote control it etc.

Although rated at maximum 2.5KW it has a 1KW setting the same as the one you have.

You can also pull it away from the wall a bit which should help get more even heat in the room.

We don't have this model but we do have a different black and decker heater (but with John Lewis branding on it to confuse matters) that we keep for emergencies.

I should say I am no expert on these things.