Electric Bill

[Keith Downing]

Wondering how much it actually costs, in electricity, to run the laser for say 40 hours a week. In my case, I also run the blower and chiller when the laser is running.

I've never really thought about this explicitly before, but the last couple of months our electric bill (we work out of a home shop) has really shot up. Trying to determine if it's the extra lasering time, or if there's something else that we've got going on. It also doesn't help that we're on a tiered pricing scale; so once you get over 500kwh per month, it starts moving up considerably for additional usage.

Plus, I don't think I've ever seen this discussed here. So I thought it'd be interesting to hear how much others have determined it costs where they live, and if it's enough to factor into your pricing during peak times; or if you just look at it as a fixed cost of doing business.

[Dennis Rech]

Wondering how much it actually costs, in electricity, to run the laser for say 40 hours a week. In my case, I also run the blower and chiller when the laser is running.
Plus, I don't think I've ever seen this discussed here. So I thought it'd be interesting to hear how much others have determined it costs where they live, and if it's enough to factor into your pricing during peak times; or if you just look at it as a fixed cost of doing business.

Looking at he nameplate ratings, my 40 watt laser draws 400 watts, the exhaust fans 150, the water pump 60 and the blower 75 for a total laser related wattage of 685 watts. At a cost of 12 cents a KW, it is a little over 8 cents an hour. A 3kw electric heater adds 36 cents an hour and 600 watts of lights are another 7.2 cents. The laptop computer is about 150 watts for 2 cents. So the whole thing is about 65 cents an hour in winter.
A laser tube replacement cost a little over $200 after a little over 300 hours for another 67 cents for a total of $1.32.

So, with a slightly bigger laser, a slightly colder climate, a little bit more powerful fan and exhaust, you could figure 2 dollars an hour.

Hope this helps.

[Kev Williams]

Our home is our business. What I have here that burns electricity:
8 computers
10 CNC rotary tool engravers
3 C02 lasers
1 Fiber laser
3 HF 'green' blowers
1 HF 'the bigger' blower
1 3000 chiller (non-refer)
1 old 20" vinyl cutter
1 really old Delta drill press, floor model
1 table mounted drill press
1 HF mini lathe
1 bench grinder
2 tool grinders
1 beveler
1 cut-off bandsaw
1 10" table saw
1 10" radial arm saw
1 4" or so safety saw
1 80 gallon air compressor
1 5 gallon air compressor
70 (I just counted 'em) 32-40 watt florescent tubes to light the place up
1 500 gallon hot tub
Central air
Portable refer AC (garage)
Evap AC (garage)
washer, dryer
2 refrigerators (28cf, 19cf)
2 freezers (20cf, 12cf)
2 electric ovens
assorted other lamps, TV's ---

Last year was our best year by quite a margin, so it's fair to say we burned thru a few kWatts :D
Summer is worst due to trying to keep cool, this is my 5 mW bill last mid-July/mid-August...
379356

And this is my latest bill, a mere 2.5 mWatts ;)
379357

Now, this all might seem like a lot, but every other month I get a graph that tells me that we use -on average- 300% as much power as our neighbors. I'm actually pretty amazed it's ONLY 300%! And I always try to look for the silver linings, such as, our equal-pay bill is less than my wife's Mustang payment :)
--and then there's the fact the power does help us make a decent living!

[Keith Downing]

Dennis, thanks for the reply. I'll have to do the math on that in the morning, seems lower than I expected though!

Kev, you've got quite a bit of machining power there. The crazy part is I have basically just 1 laser running (though I do have 4 computers and 3 cable boxes) and we hit 2.2mW last month. I don't understand how it's that high for me and just a tad bit higher for you running that arsenal. Lol

[Bill George]

Dennis, thanks for the reply. I'll have to do the math on that in the morning, seems lower than I expected though!

Kev, you've got quite a bit of machining power there. The crazy part is I have basically just 1 laser running (though I do have 4 computers and 3 cable boxes) and we hit 2.2mW last month. I don't understand how it's that high for me and just a tad bit higher for you running that arsenal. Lol

I think you need to re-read your power bill. Electric is billed in kWh. We usually run here around 800 to 1200 or so, and the cost per kWh is about 9 cents.

[Matt McCoy]

Keith,

How do you heat your shop? Do you have a YOY comparison?

[Keith Downing]

I think you need to re-read your power bill. Electric is billed in kWh. We usually run here around 800 to 1200 or so, and the cost per kWh is about 9 cents.

Our bill for February was 2,224 kwh. I assumed from Kev William's post that converted to 2.2Mw being billed. Apologies for the confusion if that assumption wasn't true.

Matt, we don't heat the shop on a regular basis, though we did have to run a heater a few days since (as I'm sure you know) we had a colder than average winter in this area.

In the last year our usage has only broken 2,000 kwh's in July and August when the AC was running 24/7. February the last 2 years was roughly 35-40% lower though, so somethings up.

[Kev Williams]

kW mW, as you can see in my bills, it's done in kilowatts.. we routinely look at 1,000 kb files on our computers and know it's a megabyte, I just did the same conversion!
(and 'megawatts' just sound more impressive :D )

oh, and beware electric heaters-- we have a mobile home some friends are renting from us, and I get the light bills in my emails. Last winter they bought one of those heaters advertised on TV, just a 1500w thing, and the light bill jumped $120 that first month.

Me, I heat my garage shop with a wall mounted ventless heater...
379386
This one was all of $219 to my door from Ebay and works with LP or NG, which I'm using. Keeps the garage 65° for around a buck a day. Not particularly cheap either but the garage is mostly un-insulated so I'm not complaining. Another thing, I have 5 machines in the garage now, and usually 4 of them are on and/or running, and the heat they give off naturally can raise the temps in here 5 or 6 degrees easy...

[Doug Fisher]

Keith -

Does Boss still send the cheap Chinese big gray exhaust extraction fan? If so, those suck lots of power (and are loud!). The label on mine specs 550 watts. I bought a replacement from Amazon that uses a fraction of the power, has variable speed, is much quieter and still moves lots of air.

[Mike Chance in Iowa]

Plus, I don't think I've ever seen this discussed here. So I thought it'd be interesting to hear how much others have determined it costs where they live, and if it's enough to factor into your pricing during peak times; or if you just look at it as a fixed cost of doing business.

It has been discussed numerous times over the years. Here are some to get you started. Use the Advanced Search feature to locate more.

https://sawmillcreek.org/showthread.php?229291-Laser-Cutter-Running-Cost-Per-Minute

https://sawmillcreek.org/showthread.php?53369-Just-got-my-first-electrical-bill!-Help!

https://sawmillcreek.org/showthread.php?207444-Howdy-from-a-new-member-and-a-question-about-energy-consumption!

[Keith Downing]

Keith -

Does Boss still send the cheap Chinese big gray exhaust extraction fan? If so, those suck lots of power (and are loud!). The label on mine specs 550 watts. I bought a replacement from Amazon that uses a fraction of the power, has variable speed, is much quieter and still moves lots of air.

It's black not grey, but probably overkill yes. I'll check to see if it has a rating on it tomorrow.

[Scott Marquez]

Keith,
There are a few things you can do, read your meter daily to learn your trend, my house normally uses 35-90 KWH a day, the best being Spring and the worst being last Winter when it was in the teens. I do this every evening at 7:00 pm and the days I miss, I use an average for the days missed. I also got an inline power meter 120volts, that I plug into to see actual power draw. Last Summer I replaced about 70 lights to LED, in an effort to reduce my power bill, which it did.
Depending where you are at, you may be spending more money on heating or cooling your make-up air then running the equipment.
Food for thought.
Scott

[John Lifer]

I've my lasers in my basement. NW Arkansas usually has pretty cold winters as compared to the rest of the south. Much closer to south Missouri, but we avoid a lot of the snow that passes thru Joplin and Springfield. :) December was Extreme. We had over a week at less than 5 degrees as a high. AND I had some of our extended family staying with us in part of the basement that is a bedroom.... It usually stays about 60-65 down here if the weather stays above freezing. It was getting down in the 55-60 degree range especially in my laser corner where I have a door and large windows and is the walkout side. So they ran a 1500watt portable heater. It costs us about $3 a day when they ran it over night. I can watch my daily usage via app, so it is nice to monitor. Laser, if I ran all day, I can see it go up, but my wife baking a two hour meal kicks it up more than all my equipment. So Yep watch out for any of the electric heaters. 1500w is 1500w, no matter what brand, shape or size.... Don't be fooled....

[kyle bonnell]

I added this all up for a large job a couple months ago and the cost was negligible. If you really want to find out what your set up is running get one of those watt meters you can plug into the outlet and it will tell you the draw and you can get the cost from there.

[Keith Downing]

I added this all up for a large job a couple months ago and the cost was negligible. If you really want to find out what your set up is running get one of those watt meters you can plug into the outlet and it will tell you the draw and you can get the cost from there.


I have been keeping track with the Kill a Watt and also our city's newly launched consumption app.

Mostly I believe it's just a lot of little things adding up for us. We don't use gas for anything so that's added some usage others don't experience (for heating, cooking, and laundry).

As far as the added cost of the lasering, the one thing I forgot is probably a big part of ours. We have a big 60 gallon, 5hp, 220V air compressor. And when we're cutting that thing cycles about 30-40% of the time. Can't imagine that use is negligible, but I will do the math on it and try to keep track of how much it's running.

[Kev Williams]

We have a big 60 gallon, 5hp, 220V air compressor. And when we're cutting that thing cycles about 30-40% of the time. Can't imagine that use is negligible, but I will do the math on it and try to keep track of how much it's running. You shouldn't be using that much air just for air-assist- I have a HD Husky compressor, same basic specs as yours, it runs about 70% when pressure-pot sandblasting @ 100psi-- If you're using the cone nozzle to deliver the air, you might consider buying or fabbing up an 'exterior' mounted air nozzle, using 1/16" ID copper tubing, you can get a much stronger stream of air using much less air in the first place....

[John Lifer]

Why on earth use a large air compressor? My cheap Chinese aquarium pump puts out plenty of air and it is about a hundred watts... Now with my 38mm nozzle it has a little needle valve. It needs all the flow it can get to get enough air.. I'll be buying a HF airbrush compressor when this one dies.... Heck I'd hate to use my 1 HP compressor

[Mike Null]

John

If you're a hobbyist the HF/aquarium pumps might be ok but if you're running customers' goods then you're taking a risk with that kind of air supply. Both, no doubt, have automatic shut-offs. That can ruin a job in a hurry.

[John Lifer]

Whatever.... My air assist is off when engraving. I haven't found anything yet that has been ruined if it is off. Ill not argue the fact on a clear acrylic it wouldn't be good to be cutting and it fail, but any compressor can fail. Would you really notice quick enough is you lost air due to a leak?

I'll still argue a five horsepower compressor is overkill for air assist unless you are running multiple lasers simultaneously. It doesn't take that much air....But it ain't my money...

[Kev Williams]

Most of us with large compressors have them for many reasons that have nothing to do with laser air assist :)

-and as long as a big compressor is already in service, there's no reason not to connect it to a laser...

And FWIW, when I find my compressor is cycling more than I think it should, it's because one of my fittings is leaking... ;)

[Bill George]

Whatever.... My air assist is off when engraving. I haven't found anything yet that has been ruined if it is off. Ill not argue the fact on a clear acrylic it wouldn't be good to be cutting and it fail, but any compressor can fail. Would you really notice quick enough is you lost air due to a leak?

I'll still argue a five horsepower compressor is overkill for air assist unless you are running multiple lasers simultaneously. It doesn't take that much air....But it ain't my money...

Agreed. You can also hear the air or aquarium pump running so you know it working. My big compressor would only cycle maybe 3 or 4 times an hour when I was using on my ULS.

[Keith Downing]

Thanks for all the opinions guys. I will say though, there's no reason to really turn this into a debate about the size of the air compressor I own. We use it for spraying and a few air tools also. And, going from the trash air pump that came with my laser to a true, regulated 20-35 psi of flow made an AMAZING difference; especially when cutting 1/4". No more charred edges, a cleaner cut, etc. So, no regrets there.

Anyways, thanks for the input on everything.