Decreased Power Bill on Downsizing

[AlmostBob]

That just doesn't add up as the lumen output is about the same........

Ciao

Nor

the living room has 12 downlights, or 1 curly bulb in a standard fitting,
therefore it does add up

standard light fittings radiate in all directions
downlights go down,
the narrower the beam, the less effective it is

 

[HiEquity]

A1

1500W x 1 hour = 1.5Kwh @ 24.5961c /Kwh = 36.8942c

SM1 (Peak)

1500W x 1 hour = 1.5Kwh @ 47.4099c /Kwh = 71.1149c

SM1 (Off Peak)

1500W x 1 hour = 1.5Kwh @ 12.7360c /Kwh = 19.1040c


Add to that anything with........

Purely Resistive / Inductive loads and multiply by anywhere between 60 & 90 days billing + 45c / day supply charge + GST...........$$$$$

Remember the +GST!

And - effective 1 July 2015 - a 4.5% price increase! Plus GST again!

BTW, most 1500W irons spend more time with their thermostat off than on during operation, so you have to at least halve those figures...

That just doesn't add up as the lumen output is about the same........

I would call it a bit of an exaggeration but not far outside the realms of reality.

The first reality is that one 55W globe produces roughly the same lumens as a 13W fluoro (or LED, which aren't any more efficient than fluoros generally, despite popular belief). It also has over 10% standing loss in the transformer sitting above it heating up your roof space (remember the insulation fires because these got covered over?).

The second reality is that a downlight design concentrates all that light in one bright "puddle" on the (often dark) floor, leaving the rest of the room in darkness. So you get very inefficient distribution of light vs an open fitting which can reflect light off the ceiling and distributes that light across the whole room, without the harsh boundaries of downlights. So you really need about 6 of those halogen downlights (circa 360W) to do the same job as a 13W open fluro fitting.

To properly illuminate a room that would otherwise have 12 halogen downlights (720W of lighting!), you will likely need around a 20W open fluoro fitting IMO....

I've been fuming over this design for the last twenty years - those things are a phenomenal waste of energy. Everyone I spoke to who had them installed back then had equated "low voltage" with "low wattage", when the reality is exactly the opposite!

 

[Norwester]

I would call it a bit of an exaggeration but not far outside the realms of reality.

Haha......I was going to just call it as bullsh@t, but I'm much to polite for that.....

Spent a lot of time in the 90's doing lx (Lux) tests for architects in both commercial and high end domestic installations and can honestly tell you that its not as simple as that due to the logarithmic nature of our eyesight, but I agree that it is something that people can get quite passionate about..... (It's a light FFS).

Downlighting has been around long before dichroic lamps even existed in domestic applications and was pretty much regarded as "application" based rather than "generalised" illumination........ie wall washing, backlighting, feature highlighting.

And that was pretty much the same for when dichroic lamps first started being used in general domestic applications - they were "application" based installs. But slowly, as the rooms grew larger (open plan living) and the light fittings got cheaper, they moved into more generalised usage.

And you are right, a lot of the initial marketing related (implied) low voltage to low power consumption, but as any good electrician knows (or should know) a Watt = a Watt = a Watt regardless of the applied voltages or currents drawn. (other than KVAR....but that's a different game again)

As for the "transporter beam" effect, well that depends on the wattage of the globe and angle of diffusion.

For example:

EXN 38/39 degree 50W lamp gives you.....

1372Lx @ 1m across a diameter of 670mm
343Lx @ 2m across a diameter of 1350mm
153Lx @ 3m across a diameter of 2070mm

Where as a:

FNV 60 degree 50W lamp gives you......

550Lx @ 1m across a diameter of 1000mm
138Lx @ 2m across a diameter of 2000mm
62Lx @ 3m across a diameter of 3000mm

(for comparison, 900 lm will give approx 127lx across 7.065m^2 as a straight conversion & rough calc not accounting for height)

So a required level of illumination really depends on the room size, absorption/diffusion factors, colours, the application required, the choice of the lamp and fitting, and in the end the clients eyesight...

And as for catching fire.......yep, all recessed light fittings will do this (even LED) if you cover them.

BTW, most 1500W irons spend more time with their thermostat off than on during operation, so you have to at least halve those figures...

Yeah, I didn't want to go into duty cycles as it gets overly complicated.......and it also depends whether Sanj is ironing overalls or a camisole.....

I've been fuming over this design for the last twenty years - those things are a phenomenal waste of energy.

Everything has a purpose. This is what happens when it's used in the wrong application.........

Seriously though, I used to love putting these in....must have installed thousands of 'em over the years...priced per point + fitting cost.........$$$$$$$$......

Ciao

Nor