On 11/28/2011 1:10 PM, DerbyDad03 wrote:
On Nov 28, 1:17 pm,
wrote:
On Nov 28, 12:29 pm, wrote:

I thought that all electric heaters were 100% efficient.

What is this site talking about when they say:

"During the process of converting electrical energy into heat energy a
great deal of it is lost. Therefore an electrical heater is left with
45% of the energy for heating purposes."

http://recomparison.com/comparisons/...ter-vs-ceramic...

Per the law of physics, they are obviously idiots. The
electric energy you are paying for, as registered by the
meter, is almost all converted to heat by an electric heater.
The tiny, negligible losses would be as heat in the wiring going from
the meter to the heater. And even that is converted to heat.



You don't need to know what you're talking about to put
up stuff on the web.

There are legitimate differences in how that heat then
reaches the person in the room, how it's dispersed,
etc. For example, a radiant electric heater that directs that
heat directly at where someone is sitting is going to be more
economical to run than an electric heater
that tries to heat the entire room. But if they both run at
1000 watts they both have the same 100% efficeincy in
converting the electric that goes into them into heat.



P.S. I'm back to struggling with whether or not I should use a
constantly running oil-filled heater (set on low) in my small workshop
or should I run a small electric heater with a fan only during those
times when I'm in the shop, usually a couple of nights a week and a
few more hours on weekends.

I have both, so the initial cost is not a factor.

IMO, the electric heater with a fan is the clear winner.
Why heat the shop when you're only there a small
percentage of the time? Or buy one of the radiant heaters
with a dish that you can pick up at Costco or Walmart for $40.
The benefit to those, besides being energy efficient, is that
you get heat instantly. Downside is that they are very
directional. So, if you stay at one spot it could be good.
If you move around, soon as you're not in front of it, no heat.

"IMO, the electric heater with a fan is the clear winner."

Even though all electric heaters are 100% efficient, one type vs.
another could be cheaper to operate, right?

Depends on the application.

Fan type can transfer heat to the air faster. Heating to a comfortable
temperature if you are infrequently in the shop should be a lot cheaper
(as trader said above).

In general, a fan type can be aimed at where you are which can localize
the heat more (with other areas colder).

Radiant could also localize the heat (as trader said above). Electric
radiant ceilings and probably floors (like hydronic ones) can be
comfortable at lower air temperatures, which can reduce energy consumption.

The heaters with Amish built cabinets are best of all with a large
advantage for the manufacturer.

You can't just compare on wattage. The amount of time the heater is on
has to be included. A fan unit that infrequently heats a shop should be
higher wattage than a heater that keeps the shop heated.


Obviously 100% of 2 kW is going to cost less than 100% of 5 kW over
the same time period, but how does one compare the various types of
heaters to determine the operating cost?

Disregarding the specific situation regarding my shop, are oil-filled
heaters cheaper to operate than fan-based heaters since the oil
retains/emits the heat even when the element is off?

If I wanted to determine how much it costs to run an oil-filled heater
"24/7" I'd need to know how often it actually cycled, which would be
based on the temperature of the space, which of course would vary over
time.

The major advantage of oil-filled electric heaters is that the heat
transfer is over a much larger area than with rod type electric
elements. The surface temperature is much lower. In a baseboard unit,
oil filled is not likely to cause a fire. And if I remember right
receptacles can be in the wall above them, but not above a rod type
baseboard.

--
bud--