Save Money On Lighting


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Table of Contents

  1. How to Save On Lighting
  2. Fluorescent Bulb Payback Time

How To Save On Lighting

In this article, I will attempt to help you to keep your rooms adequately lit while keeping your power consumption as low as possible. Please click the links provided below for more information.

  • Carefully choose the wattage of the bulb based on the room that you will put it in. Some rooms don’t need very bright bulbs, such as passageways/hallways, living rooms, garages, small rooms, bedrooms, verandas, outside, and anywhere else where you don’t need a bright light. Some rooms such as those that you would read in should be well lit, or you should use a decent lamp for reading, which is an even better idea in my opinion.
  • Replace your outside lamps with the motion sensor activated type. They are off most of the time, saving electricity, and they turn on when someone enters the premises, which may give them the feeling that they are being watched, and that will also alert you that someone is there if you see the light turn on yourself, so you can check.
  • Cloudy dark climates: People living in countries such as the United Kingdom, Germany, Norway, Russia, etc, sometimes need to turn on their lights during the day if it is too dark, and this is common, causing them to use more electricity for lighting because their lights are on for longer periods of time. They especially need to try and apply as many of the lighting tips on this page as possible. Especially using very low wattage lamps in rooms and using very low wattage lamps on the kitchen counter or table so that they can do what they need to with adequate lighting. I recommend this because less light (hence electricity) is required to brightly light a table than or counter than is required for an entire room. Better yet, during the day, turn off the lights, but use very low wattage (5-15 watts) lamps to illuminate tables, counters, and other work areas.
  • The most frequently used bulbs should be as low a wattage as possible, while still providing enough light. A brighter bulb like the 23 watt example may be more appropriate for the store room than the passageway, anyway.
  • Mechanics and other technicians should use work lights in their area which are focused on their work area instead of relying on high wattage ceiling lamps. If you have bulbs of varying wattages in your house, then you should check their wattages and move them to the appropriate rooms. In other words, if you have a 23 watt bulb in your passageway or veranda, and a 7 watt bulb in your store room which you don’t enter often, then move the 23 watt bulb to the store room, and move the 7 watt bulb into the passageway.
  • Turn off lights in rooms if you will leave them for more than 20 minutes.
  • Replace inefficient light bulbs such as incandescent ones with more efficient bulbs (Ideally fluorescent bulbs, but please shop for the LEDs carefully, some are very inefficient. Divide the light output in lumens by the wattage and that will give you the lumens per watt or lm/W figure).

The average efficiency of incandescent bulbs is approximately 1/5th of that of fluorescent bulbs. That means that fluorescent lamps produce 5 times as much light per watt. The average luminous efficacy of incandescent bulbs is 5-17 lumens per watt (usually 10), and 50-72 lumens per watt for fluorescent bulbs (usually in the 50s). In terms of ultraviolet (UV) light emissions, fluorescent bulbs do not emit a hazardous amount of that, because they are internally coated with phosphor, which absorbs UV light and re-emits white light.

Fluorescent Payback Time

In order to understand what I wrote below, you need to read this first.

A $4 14 watt CFL is as bright as an 80 watt incandescent bulb (the brightness is roughly 800 lumens, sometimes it is more, or less if it is a cheap bulb).

Incandescent power consumption: 80 watts * 8 hours of operation per night = 640 Wh (watt-hours) per night. Multiply that 640 Wh result by 30 days since there are 30 days in a month, and the result is 19,200 Wh per month, which is 19.2 kWh per month. That would cost you $1.92/month if your electricity rate is $0.10/kWh (USD).

A 14 watt fluorescent bulb consumption: 14 watts * 8 hours of operation per night = 112 Wh per night. Multiply that 112 Wh result by 30 days and the result is 3,360 Wh or 3.3 kWh per month. That would cost you $0.33 per month if your electricity rate is $0.10/kWh.

The incandescent bulb costs $1.59 per month more to operate than the fluorescent bulb, therefore, if you divide the price of the $4 fluorescent bulb by how much more the incandescent costs you to operate per month, the result is a financial payback time of 2.5 months, and that doesn’t include the price of the incandescent bulb, which would actually shorten the payback time of the CFL by roughly a month.

  • For those who prefer the colour of incandescent bulb light to that of fluorescent bulb light, you can find fluorescent bulbs which are that colour, as well as LED bulbs, but look carefully. I use the Sunrise lighting bulbs.
  • I would recommend using fluorescent bulbs which are no more than 14 watts for most rooms, but 7 watt bulbs for hallways/passageways, small rooms, bedrooms, garages (some garages), 7 or 5 watts for closets, and 7-14 watts for bathrooms. When reading, you should use a desk lamp, or you can use a 23 watt ceiling lamp in that room, but only if you consider that to be necessary.
  • I would recommend (to businesses especially) setting up automatic lights which switch themselves off after the rooms are empty.
  • It is a good idea to recycle what you use. Find somewhere to drop off your light bulbs and other items to be recycled. I would recommend buying fluorescent lamps which have replaceable tubes. So that you can salvage whichever part goes bad, whether it is the ballast or the tube.