kjpro @ usenet.com wrote:

No kidding... this is what people don't understand.

Which produces more heat?

A 1 - 500 watt halogen light.
B 5 - 100 watt light bulbs.
C 1 - 500 watt electric heater
D 1 - 500 watt quartz heater
E 1 - 500 watt baseboard heater

Which answer below is correct?

1 They all create different amounts of heat.
2 A & B are equal, C & E are equal, but D produces more heat.
3 A, B & D are equal and C & E are equal, but C & E produce more heat.
4 (A,B,C,D & E) All create the same amount of heat.

Correct, but incomplete, answer (have renumbered answers) is 4

But complete answer is:

A,B and D produce more radiation heat
C less radiation
E most heats buy convection

Therefore, if you are sitting exposed to sources A, B and D, you feel
warmer with the same power (sounds strange ?) as of C or E.

If you are interested ONLY in heating a room, answer 1) is ok.
But if you are interested in heating people (for example, outdoor),
sources A, B and D are very efficient options.

Let us put it this way: A,B and D are most efficient in delivering the
same amount of power of C and E, but where you need it mo on your body.

Example: a keep 64 F at home. When I am walking around it is a
comfortable temperature. But when I sit down, I start to feel a little cold.
Solution: a 150W halogen lamp with reflector pointed in my direction.
150W is not that much power, but you have to compare it to your body
heating power (about 100-200W), so if you could deliver that power to
heat yourself and not the walls of your house ... :-)

R.L.Deboni