Do you run a hotel or commercial facility? Switched to CFLs but your energy bill didn't go down much? Here's the shocking truth...
A little-understood fact about electricity is that there's more to it than just "watts". Most commercial and industrial users are billed in KVA. If you don't know what that means, you're not alone! KVA means "kilo-volt/amps", or thousands of volt/amps.
If you remember some basic high school electricity, the idea that "volts times amps equals watts" might sound familiar. So what's KVA then? In a perfect world, a volt/amp should be the same thing as a watt. But of course, it's not a perfect world.
A simple device like an incandescent bulb - which is really just a glowing heat filament in a glass ball - draws power in a very simple and predictable way. Remember: AC means "Alternating Current" and you've probably seen the wavy line that represents AC power. An incandescent bulb consumes power exactly as it comes out of the plug. No muss, no fuss.
However - a Compact Fluorescent light (CFL) is nowhere near so simple. It has a lot of electronics inside that little white blob of plastic at the base. And, you guessed it - it's a messy eater! The typical CFL takes the power in a very spiky manner, resulting in a low "power factor" and it kicks back noise and spikes into the power line along the way. Bad. Most CFLs only really use 50 - 60 % of the power that they are fed. It sounds like a good thing, but in fact it's the opposite.
Think of it this way: You decide to throw a big party, so you order a stack of pizzas from your favorite pizza joint. You say "I'd like 10 pizzas please". Then your guests take a couple of slices from each one, and you end up with a total of about 4 pizzas worth of leftovers. So you call up the pizza joint and say "we only ate 6 pizzas, so we're only going to pay for that much!" You can imagine how that would go over!
This is pretty much what CFLs do with the power they receive. Amazingly, the utilities actually let you get away with it right now - if you're a residential user. BUT... the bigger users are not so lucky. Commercial and industrial accounts have to pay for all 10 pizzas, not just the 6.
The 10 pizzas are the "KVA", and the 6 pizzas are the "watts". If the power factor is low (like .6) it means that 40% of the power delivered is not used. But the power company still has to deliver it, which means the power has to be generated, and the wires have to be big enough to send it, and the other parts of the utility have to be able to handle it. In the pizza analogy, the store has to bake all 10 pizzas, it has to deliver them, and it needs a vehicle big enough to carry them all. So you better eat all the pizza, not throw half of it away!
So, what's it all mean? If you operate a hotel and you've got 13 watt compact fluorescent bulbs, but they have a power factor of .6, you will be billed NOT for 13 watts, but for 22! (KVA) The math is simple: 13/.6 = 22 .
And that is why your energy bill didn't go down as much as you expected!
In your home, you get away with it. Sort of. While you don't directly pay for the bad power factor, you still pay for it indirectly. The power company has to build all that big expensive infrastructure to deliver the extra power that gets frittered away, and you end up paying for it in your taxes and in the overall energy rate.
Now that we've got you thinking, you might be wondering "hey, LED lights have electronics too! What about their power factor?" Good question. The power factor on our Par lights is over .9, in some cases as high as .95! By the way, this isn't true of all LED lights, some have power factors almost as low as CFLs because their driver circuits are not well designed.
Click here to see our complete line of LED replacement lights, with high power factor.