How do you do the math for the cost of a light bulb or any electric appliance?

Question

To help the environment I want to know how and to keep my electric bill down. Electric water heaters, oven, and light bulbs. All I hear the environmentalist say is turn off the lights.

Answer 1

Most utility companies in North America send you a bill based on the number of Kilowatt hours your house hold consumes. A kilowatt is 1000 watts. If you consume 1000 watts of power for an hour, you will be billed 1 killowatt hour. Here is an explanation from Wikipedia:

"Consider a setup with two 50 W light bulbs (100 W total) left on for 10 hours per day. The setup will consume 1 kilowatt-hour per day. If a power company charges $0.10/kW·h, then those two light bulbs will cost $0.70 over the course of a week."

Just about all major appliances and electronic devices are required to have their power usage somewhere right on the appliance. By doing a little simple math, you can do an inventory of your power consumption in fairly short order.

Remember that devices that are energy star compliant use significantly less power when they are in sleep mode. Most of these devices also allow you to adjust their sleeping and waking intervals.

Answer 2

The practicalities of the maths involved with this do, in some cases, make it almost impossible. Light bulbs and water heaters without a thermostat use a constant power. A light bulb rated at say 100 Watts will use 100 Watts/hour all the time it is switched on. Things like ovens, shower heaters and some electric kettles have thermostats. These items will use a rated power when switched on, but, at a preset temperature they will switch off until the temperature drops. Unless you put a power meter in circuit with these items and watched them continuously, you wouldn't know at what point they were using their rated power and when they were using nothing. Your heavy users are the things with heaters in them. Use these as sparingly as you can to keep your bills down

Answer 3

Here's how to estimate costs/savings:

First, let's assume you replace items at the end of their "useful life." Which i s asensible way of doing it--it means the money you spend to "go green" is limited to the difference between what you actually spend and what you would have had to spend anyway to replace an item, whether it's a light bulb or a car.

The math: If the energy-efficient item costs more than a more conventional alternative (not all do--and if efficient alternatives are cheaper, it's a no-brainer) take the difference in cost between the two chooices--that's the added cost of the energy-efficient choice.
Next, figure out how much energy you will save (many products have guides to help you figure this out) and estimate how much that reduction in energy consumption will save you per month. Finally, multiply that by the expected lifetime of the device--that gives you the total cost savings you can expect. Subtract that from any added cost of purchasing the device. Usuallly this will give you a negative number--you save more in the long run than you pay out to start with. If it is a positive number, that's the long term cost to you of energy-efficiency in a particular case.

Although, quite honestly, there are very few situations in which you will not save money in the long run. Even adding solar panels, while expensive, are long-term money savers with today's technology.

Answer 4

Very simple.
Watts of your actual light bulb 60 Watts
Watts of the new efficient light bulb 23 Watts
Difference 37 Watts
Hours that you light the bulb per yr 1,200 Hours
Energy Consumption 44,400 Watt hours
Divide that by 1000 to get KWH 44.4 KWH
Cost per KWH $0.10 /kWh
Saving per bulb $4.44 / bulb
20 Bulbs in a house hold $ 88.80 per yr

To get the right amount you need to know how many hours you operate the bulb and the cost of your kWh. Yo can see the cost in your utility bill.

You can save water and electricity and avoid water pollution when you use a laundry ball to wash your clothes.
Look at www.laundryball.net
Good luck and save as much energy as you can.
We can help reduce global warming.

Answer 5

CFLs are basically reliable in purposes the place you're no longer turniing lights on and stale plenty. each and every time you turn a CFL on, in simple terms a sprint ballast blasts off. The balast is important to tutor the easy on. So, in places like a bathing room the place the lights are grew to become on and stale plenty, the existence of the CFL would be shortened severely. while you're basically turning the CFLs on as quickly as an afternoon, they'll final a protracted time and make up for the fee differential...yet once you turn them on/off frequently, they'd have a plenty shorter existence and not be rather well worth the extra funds.

Answer 6

Take the number of watts times the time it is operating to get the watt-hours. For comparing light bulbs you compare the lumens produced divided by the watts consumed.