Could someone please help me suggest the most energy efficient, cost saving solution for heating a small study room? Besides of course layering up. I am renting so only portable heaters.. ideally would like one that can cool as well. My budget is around the $500 mark (totally arbitrary amount), but of course would like to save as much as possible.
Thanks!
My solution is usually a combination of the heat generated by my U2711, my PC and lazy patch. Strongly recommend a lazypatch.
If you are heating up the whole room, then those oil column heaters are relatively effective and less dangerous. A 6-7 fin for a small room might cost you less than $50. They do take ages to heat up, and don't be shocked at your electricity bill.
However if you only want to heat up a specific spot when you are there (for example just around the desk while you scanning through OzBargain at night :), then a fan heater would give you a quicker result.
Remember that heat is spread through radiation, air movement, and conduction. For heaters, mostly the first 2 apply.
From my own experience, I have found halogen heaters (the $25 kind) to be quite good. Reason:
* they usually have different settings, e.g. low, med, high. The low setting uses about a third of one of those "blowing" heaters (which ought to be illegal - they use 2400 watt / 60c per hour) so "only" around 800w, or 1200w on medium.
* they distribute heat quite effectively through radiation as well as air movement (by convection), whereas the "column heaters" tend to rely on air movement/convection only. Also, they can "turn/pivot" automatically resulting in even distribution.
I find those blowing heaters less useful - they heat up a room fast, but unless you keep them running it gets cold fast. They rely on heating up the air, whereas with a halogen heater you have the benefit of both warmed up air as well as direct radiation onto you. I think halogen is more energy efficient if you use it for prolonged periods of time.
A convection fan less panel heater will be the cheapest to run for a study/bedroom. Slow initially to heat up but keep a nice mild temperature without being 'harsh' or requiring you to sit 20cm from it to feel anything. Not to mention will cost less than 7-10 cents / hour to run (depending on size)
Otherwise a fan heater with ceramic element for something to take the chill off and blow at you.
Oil heaters and cheap fan heaters will cost a fortune to run.
thanks ch4rgd, could you show me an example of a model of the convection fanless panel heater?
It actually doesn't matter much, other than keeping the room sealed. Assuming gas/fire is not an option there are two ways to heat the room:
1: Direct electrical heating. Thermodynamics says that these are all the same, though fans may mean that they spread the heat faster over time it is all the same.
2: Air conditioning. If you get a portable air conditioner with reverse cycle it can pump heat from outside the room. This is the only way to get more efficient, but to get one that can do this well is expensive, and tricky in a portable unit.
Personally I would go with option 1, and just get something that isn't going to start a fire.