I was amazed about how simple this is and how much sense it makes. Pelmets are those old fashioned protections for the top of the curtains. Over time we have obviously forgotten that they serve a purpose and delegated them to the realm of old fashion decoration. However the did have a purpose and can save a lot of wasted energy in the form of heat. So how do they work? We all know that hot air rises and cold air falls. So the hot air from our heating rises to the top of the room and the cold air to the bottom and this is what happens...
How Pelmets drop your heating bills dramatically
As soon as the hot air reaches the level where the top of your windows are, the air round the windows cools down and as cold air has a tendency to do it falls. As the air falls it draws more air in behind it, cooling it too and the cycle repeats and a thermal current is started where hot air is sucked from the top air cooled via the windows and pushed out the bottom. If it's a cold night you can test this out. Go over to your curtains and place your hands at the bottom. You can feel a cool draft of wind. A pelmet works like so....
The Pelmet acts as a stopper to this flow of air. The air behind the curtain is still cold and your curtain traps the cold air out, as it should. But as no (or rather very little) air is flowing to the top of the curtain so the thermal flow is stopped and your room stays warmer. Install a pelmet from some spare wood or material and see how much warmer your room is and watch your power bills (and hence usage drop).
Simple, cheap and it makes sense. Give it a go.