how much does my light cost me to run?

Two ways I'd go about this...

Figure out your cost to run light, which is:
$ per month / kWh used over that month / 1000 = $ per watt.
$ per watt x 155 x hours light is on per month = cost to run light for 1 month.

Another thing you can do is go and replace all or many of the incandescent bulbs in the house with equivalent output CFL bulbs. Then calculate the difference in usage from the bulbs to show that you have saved power usage equivalent to what your light is using.

 

An average light system will increase electric cost by $8 to $20 a month. Multiply the bulb wattage by the number of hours in use, and divide my 1000. So yours would 155 watts * 12 hours a day = 1860 / 1000 = 1.86 kwh. Look on your electric bill for the price of a kilowatthour (kWh). Multiply 1.86 * your cost of electricity in kWh. That will be your 12 hour use for the light. One day. Multiply the 1.86 * kWh cost and then multiply by 30 to get the monthly total. US average is $.12. Yes 12 cents per kWh. 1.86 * $.12 = 6.69. Please check my math but I think you're using less than $7 a month in power. You're barely using any power. If they want to save money, tell them to turn off stuff they're not using. How wasteful can you be? Not you I mean your roommates. I think they owe you some money.

What’s in a Watt? Power vs. Energy
by Yoram Bernet in BlogPost

One source of confusion that we see among newcomers to the energy aspect of sustainability is the difference between watts and watt-hours. This confusion can wreak havoc when looking for opportunities to increase efficiency.

A watt is a unit of power. It gives a notion of how strong something is. For example – a 150 watt bulb is stronger (brighter) than a 60 watt bulb. Energy, on the other hand, is the production of a certain amount of power for a certain amount of time. So, while power may be measured in watts (W), energy is measured in watt-hours (Wh). A watt-hour is equivalent to producing a watt of power for one hour.

Consider our two bulbs; although the bulbs have power ratings (60W and 150W), they draw no energy just sitting there. But – for each hour that the 60W bulb remains switched on, it consumes 60 Wh of energy. Similarly, for each hour that the 150W bulb remains switched on, it draws 150 Wh of energy.

Imagine lighting the 60W bulb for five hours but the 150W bulb for one hour. This would require 300 Wh (5 hours x 60 watts) of energy for the 60W bulb and only 150 Wh (1 hour x 150 watts) of energy for the 150W bulb. Although the 150W bulb is more powerful than the 60W bulb, our lighting schedule requires more energy to light the 60W bulb than it does to light the 150W bulb.

One place we see this confusion really misleading people is in the use of power meters to compare the cost and environmental impact of devices. Consider for example, an industrial oven rated at 100 kilowatt (a kilowatt or kW is 1000 watts). Compare to a lighting system rated at 5kW. Naively using a power meter to measure each device’s power might tell the story that the oven is a bigger offender than the lighting system and that efforts should be focused on finding a more efficient oven.

But – what if the oven is only used one hour per week? Then it consumes 100 kilowatt-hours (kWh) per week (1 hour x 100 kW). If the lighting system operates for 10 hours per day, it consumes 350 kWh (70 hours x 5 kW) per week! The oven may be higher power, but the lighting system is consuming more energy and it’s energy that we pay for and that has environmental impact. In conclusion – we’d really like an energy meter to compare devices rather than a power meter.

So ,for each hour that the true 155w led is working, it's using 155 Wh(watts per hour). 12 hours on in a 24 hour cycle would give you 1860 watts. How much electricity does my television use? Most TV's use about 80 to 400 watts, depending on the size and technology. Using a sample cost of 15¢ per kilowatt-hour and five hours of viewing a day, that's $1.83 to $9.13/mo. ($22 to $110 per year). If the tv stays on 24 hours a day, then I would think the money is being wasted there. What kind of bulbs throughout the house?
The power consumption of a computer varies depending on whether it is a desktop or a laptop: A desktop uses an average of 200 W/hour when it is being used (loudspeakers and printer included). A computer that is on for eight hours a day uses almost 600 kWh. So their computer uses on average 200 Watts/hour when on. Computer on all day uses almost 600 kilowatthours. Two computers and a tv is where the energy is going. Not your usage.

Look on the back of your freezer for the sticker or plate that shows the unit's annual wattage usage. To calculate how much it costs to run, take the annual wattage figure – using 1,235 kilowatt-hours for a pre-1980 chest unit – divide it by 12 to get the kilowatt-hours per month, or 103. Check your utility bill or log on to your power company to determine your baseline kilowatt hour rate. In Northern California, for example, Pacific Gas & Electric Co's baseline kilowatt-hour rate starts at 13 cents, as of publication time. A unit that uses 103 kilowatt-hours per month will cost about $14 a month to run.

 

I think your math may have been wrong (or I wrote my thing wrong).

What is the total bill for one month?
What was the total kWs used during that month?

 

You are not the source of high energy usage. My roommate also once tried to tell me my 150 watt hps was making the electric bill way too high. After doing the math I realized they've got three tvs, 2 computers, fridge, stove, stereos, everything in the house is on all the time, and they trying to blame me. Well, you gotta pay more cause you got a light. Bullshit. It's not me it's you.

 

Electricity is sold in Kilowatthours(kWh) not watts. You're not spending 8000 your spending like 7 bucks in electric.

 

My HPS only uses like $10 or $12 a month for real.

 

I'm sorry I thought you just had Roommates. my bad. They probably won't understand but the truth is your light uses very little energy.

 

I always try to turn off lights that aren't being used. Drives people crazy but do it. Did you turn this off? No not me. Always turn the air conditioning up and the heat down. Turn off the computers when not being used. Turn off the tv. Be a power nazi. An electricity nazi. I control the power! Not you! Especially that deep freeze using power for no reason. That's what I did. Just be aware you're using more energy so make changes to save money accordingly. They will thank you later.

 

You will do well my son.

 

sure fire way to know, buy a watt meter and put it between your light and the wall socket. Can be had on ebay for $15. Your roomies are douches and know not what they are talking about. The upside of this is that once you have established that it is not you, you can move the watt meter around the house to find the culprits.

Even if you ran during peak hours at 155 watts @ 12 hours * 30 days <= $10 a month
There are calculators for this on the net, go to your local utility companies website (hydro one in Canada)

 

His douche roomies are his grandparents so... see calculation at top of page.

 

if you really want to know go lowes or home Dep and buy kill a watt meter

Sent from my SM-N910P using Grasscity Forum mobile app

 

thats the best advice ive heard about buying a watt meter ,,,,you can also use it on you grandparents tv and it'll show the how much that uses every hour etc ,,i use usually a small 250w sonT sodium light for flowering ,and ive never noticed any change in the electric bill ,,if you do get one of those meters that show how much the appliance is using plug it in to the washing machine and show them how much thats using ,,,mac

 

Here's how you figure it out...after the @ sign, that's how muc they charge per kilowatt-hour. Actual draw of your item times number of hours it is on, divided by 1,000 is the kilowatt hours it uses daily.

Average household uses 35-40 kilowatts of power a day...turning on 4 100 watt lightbulbs for 10 hours will increase that by 10% (you used 400 watts per hour for 10 hours, 4,000 watts, or 4 kilowatts)

Your "300 watt" LED is an effective rating...what's actual draw? THAT is what you figure from.
If I remember right, 175 watts is actual...so your added draw, if you run it 24/7, is 4.2kWh/dy...so you're increasing the bill between 10% and 13% per month, minimum.

On JUST lights.