Energy Efficiency Reference/Industrial/Assessment Walkthrough

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How to Use the Checklist


This checklist is designed for quick scanning. See the Reference Section for more detail on opportunities identified.

Following is a key to bullet icons identifying the type of information being presented.

2 Notes

«  Tip

C Rule of thumb

N Warning or Caveat

$ Look for

? Ask

7 Measure

1 Additional opportunities

¨ Sign of potential inefficiency to correct

ð Potential opportunity

L Potential disadvantage

$ Cost savings estimation 1

Following is an example of how the checklist is organized:

This is the equipment, system, or subject being covered

2 General Notes:

General notes on the equipment, system, or subject.

«  Tip

C Rule of thumb

N Caveat

$ Look for:

o Flag or sign of a potential inefficiency to correct

Notes about flag

ð Potential opportunity for action to improve efficiency.

General notes

C Rule of thumb

$ Value estimation method[1]

« Special tip

L Disadvantage

N Warning

7 Measurement(s) to take

? Ask: (Signs of potential inefficiencies you may discover by asking questions)

7 Measure: (Signs of potential inefficiencies you can find with measurements)

1 General Opportunities:

The Opportunity Checklist Common Equipment Lighting

2 General Notes:

«  Use binoculars to identify high bay lights – particularly fluorescent lights

«  It can be easiest to identify the type of lights installed by checking the stockroom

«  Light output from a light source is measured in lumens

«  Light available at a particular location is measured in footcandles

«  Helpful reference tables:

Common light source characteristics



Lumens /Watt

Restrike (Min.)

Full Output


Avg. Life (1000 Hours)


Warm yellow

8-24 *










Mercury Vapor

Very blue white – tends to get greenish with time





Metal Halide

“White”, significant color shift with time





High Pressure Sodium

Yellow orange





Low Pressure Sodium

VERY monochromatic yellow





  • The most common incandescent lamps yield approximately 17 lumens/watt

Variations in Fluorescent lamp and fixture choices

Lam p


Relative Energy Consumption for same lighting level as standard lamp and magnetic ballast.


Standard Magnetic



Efficient Magnetic






Standard Magnetic



Efficient Magnetic






Matched Electronic Ballast


[1] Unless otherwise noted, estimate rules of thumb assume: 5¢/kWh for electricity, ******/CCU for natural gas, 8 hours a day (one typical shift), 5 days a week, 52 (perhaps this should be 50) weeks a year. Adjust for actual conditions (e.g. x2 for two shifts). Be aware that estimates are rough and intended only for developing “ballpark” estimates of potential.

$ Look for:

o Lights on in unused area

ð Turn off lights (manual)

Because there is no investment this can be the simplest most cost effective method to save on lighting energy.

L It hard to change worker habits. There is no guarantee that a directive to turn off lights in unused areas will be effective.

ð Install occupancy sensor

This offers a more reliable method to obtain savings as it is not operator dependant.

ð Replace high pressure lights in low use areas with fluorescent lights for quick on and off control

Although they can operate more efficiently, lights with long restrike times, such as high pressure sodium lights can be a poor choice for low use areas. Because they take so long to warm up and provide enough light to work by, they are frequently left on continuously.

o Lights on outside in daytime

ð Turn off lights (manual)

L This measure is only as reliable as the operator(s)

ð Install photo electric sensor

This offers a more reliable method to obtain savings as it is not operator dependant.

ð Replace or maintain faulty photocontrols

Often when lights are on during the day it turns out that photocontrols are already installed but have become inoperable or dirty.

o Higher lighting levels than required

Use a hand held light meter to measure light available in work areas. Hold the meter at work level. Refer to the table above for recommended lighting levels. See Illuminating Engineering Society of North America (IESNA) guidelines for more detail.

Common lighting requirements*




    Very Complex






Control Room


Mechanical Room


Corridors, Lobbies





         Large items
         Small items




  • See Illuminating Engineering Society of North America guidelines for much more detail.)

ð Reduce lighting level (e.g. in warehouse areas)

It is common for some areas to have excessive lighting; particularly warehouse space, walk-in freezers, and hallways.

There are a number of strategies for reducing lighting: Lamps can be removed (for fluorescent fixtures the ballast will still consume some energy), fixtures can be rewired to allow partial to full lighting, or new efficient fixtures can be installed with a reduced design point for the lighting level.

L Lighting level may be perceived as a “health and happiness” issue. Even if an area may have higher lighting levels than recommended by IESNA it may go against the local culture to reduce lighting.

ð Reduce overall lighting and install task lighting

This approach can deliver better lighting where it is required, while reducing the overall lighting in an area.

L Unless task lighting is installed to be easily modified, an excellent task lighting layout can quickly become obsolete as manufacturing operations change.

o Incandescent Lights

ð Replace low bay incandescent fixtures with fluorescent fixtures.

C Estimate: energy savings of 80%[1]

ð Replace incandescent lamps with compact fluorescent lamps.

Compact fluorescent lamps offer a quick and simple opportunity to retrofit to more efficient lighting.

C Estimate 80% increase in efficiency2

L Compact fluorescent lamps can represent a theft risk.

ð Replace high bay incandescent fixtures with high pressure sodium (HPS) lamps in areas where color is not important

C Estimate 80% increase in efficiency2

L Some might not like the yellow orange light. It may also be unacceptable where good color recognition is required (example: a product grading area)

L HPS lamps take time to restrike and then come up to full output when first turned on

ð Replace incandescent fixtures with higher efficiency metal halide (MH) fixtures in areas where color is important such as product grading area.

MH lamps offer a “white” light preferred by some. Generally they are not as efficient as HPS lights.

C Estimate: 80% increase in efficiency2

L MH lamps take time to restrike and then come up to full output when first turned on

o Standard fluorescent lights

Standard lights to replace:

40 watt T12-CW, WW, WWX, and Daylight 34 watt T12 WWX, and Daylight

75 watt slimline CW, WW, WWX, and Daylight 60 watt slimline WWX, Daylight

110 watt HO CW,White, Daylight

ð Replace standard fluorescent lamps with high efficiency fluorescent lamps.

Many of the “standard” lamps listed above are no longer being manufactured. “Efficient” lamps are becoming the new standard. Verify that these older “standard” lamps are being used before making this recommendation.

C Estimate: 10% increase in efficiency 2

ð Replace Standard fluorescent and magnetic ballasts with T8’s and matched electronic ballasts

C Estimate: 35-45 % increase in efficiency 2

L It can be problematic to have T8 and standard fluorescent fixture at the same facility. Although standard fluorescent lamps fit in T8 fixtures, the ballasts are not matched.

ð Replace fluorescent fixtures with low bay metal halide fixtures.

Metal halide (MH) lights are more commonly chosen for their white light than their efficiency. Savings will only be available for specific selections of MH fixtures. For some combinations of existing fluorescent fixtures and replacement metal halide fixtures, smaller low bay wattages in particular, energy use could increase.

o Magnetic ballasts on fluorescent lights

ð Install electronic ballasts

C Estimate: 10-25 % increase in efficiency

It can be difficult to determine the type of ballast installed.

[1] Efficiency increase estimates assume maintaining same lighting level.