Best Practice Guide

Food and Beverage Growers and Processors

Introduction

Planning an Energy Program

Funding and Approval

Commissioning

On-the-Farm Energy Use

Lighting

Highbay and Lowbay

Hallways and Corridors

Restrooms and Closets

Outdoor Areas

Signage

Daylighting in Big Boxes

Building Envelope

Central HVAC System

Boilers

Steam

Combined Heat and Power

Compressed Air

Refrigeration

Motors

Demand Response

Distributed Generation

Water Use


Fetzer Vineyard

J Vineyards and Winery

Mission Foods

S. Martinelli and Company

Sara Lee

Vineyard 29


View the Glossary

Lighting

Highbay and Lowbay

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Lighting and Energy Use
Imagine a manufacturer in California who still relied on the telegraph and operator-connected telephone for their communication - it would be a wonder if they were still in business given today's age of the Internet. While this sounds silly, many manufacturers actually do rely on technologies from the 1950s for their lighting choices.

Lighting can be a forgotten system. It has no perceived direct affect on production or profits, and lamps that have always worked, still work. Money invested in new conveyor belts or boilers, or in robotics and digital controls, on the other hand, has an obvious and measurable impact on operations. For this reason, even in the most state-of-the-art facilities, managers faced with competing choices tend to gravitate towards improvements in process equipment rather than building equipment.

However, upgrading the lighting system is one of the best energy efficiency measures a facility can undertake in terms of payback, ease of implementation, energy savings, and secondary benefits.

Lighting accounts for nearly 7 percent of total electricity use in industrial and manufacturing facilities, but accounts for almost 40 percent of electricity consumed by building (not process) equipment. Lighting upgrades can usually be done in-house and as part of routine maintenance, making these easy, non-disruptive, low-risk investments with relatively quick payback rates. As much as 50 percent of current utility costs related to lighting can be cut with energy-efficient lighting.

A popular strategy is to adopt lighting projects as an initial energy project. The benefits are immediate and visibly tangible to employees and clients - lighting projects always improve people's ability to see clearly and generally make the indoor environment more attractive and appealing for occupants. Soon, you may find new people on-board with energy management as they "see" first hand the benefits. Best of all, cost savings can help finance (and justify) additional energy measures, and prove the bottom-line benefits of energy management.

Industrial Lighting Systems
Industrial lighting systems are distinguished by the height at which fixtures are mounted: highbay lighting systems are 25 feet or more above the floor, whereas lowbay systems are those less than 25 feet. The higher the mounting, the more lumens are needed to produce enough light. Focused, precision work also requires high lumen output and good color rendering. In storage areas or areas unoccupied for part of the day, lower lumen levels and lighting controls that shut off lights when nobody is around are good ideas.

Whenever evaluating any lighting project, consider ways in which overall lighting quality can be improved. Studies have suggested that improvements to lighting quality may boost worker productivity, improve plant safety, and reduce eyestrain and headaches.

To quickly tell whether or not a lighting upgrade might make sense, ask these things:

  • Are T12 fluorescent or mercury vapor lamps still installed?
  • Do any of the fixtures make buzzing noises or flickering light?
  • Was the building constructed before 1978 when Title-24 building efficiency standards first went into effect?
  • Are cooling loads in the workspace a concern, i.e., is it too hot indoors?
  • Have employees complained of eyestrain or vision-related headaches?

A "yes" to any of these questions indicates that it may be cost-effective to upgrade your lighting system.

Relamp, Retrofit or Redesign
There are three general levels of lighting upgrades:

  1. Relamp - lamp replacement, usually scheduled as part of regular operations and maintenance; in a group relamp, all lamps are replaced in a single maintenance project in order to achieve uniform lighting levels with a minimum amount of disruption.
  2. Retrofit - lamps and ballasts are replaced; good opportunity to simultaneously upgrade control equipment like occupancy sensors and timers.
  3. Redesign - lamps, ballasts, and fixtures replaced; often with a redesign, delamping occurs (i.e., less fixtures are needed, so some can be permanently removed).

Relamping is best suited when funding is limited and when switching out T12 fluorescents for T8s.

Retrofitting focuses on the ballast as well as the lamp. Ballasts regulate electricity moving to the lamps. Magnetic ballasts typically used in older systems are being replaced by newer, more energy-efficient electronic ballasts (building codes and manufacturing standards are mandating the turn over of magnetic ballasts). Upgrading to an electronic ballast can result in savings of the same order of magnitude as upgrading from T12 lamps to T8s.

Depending on the system to be replaced, redesigns can sometimes result in the quickest payback and the most energy savings. Delamping unneeded fixtures is one of the most important ways to reduce energy use. When new, better lamps and ballasts are installed, such as high-output T5 fluorescents with electronic ballasts, lighting quality is significantly improved - those old fixtures will not be missed!

High-Intensity Discharge (HID) Lighting
Lighting in older facilities typically employs some sort of high-intensity discharge system, particularly in highbay applications where greater lumen output is needed. The HID family includes mercury vapor, metal halide, and high-pressure sodium lamps. Mercury vapor lamps, the first to be invented, are not often used because of their poor color rendering and inefficiency. Metal halide have a much better efficacy, meaning the ratio of lumens to watts, and can achieve very accurate color rendering, as measured by the color rendering index (CRI). High-pressure sodium (HPS) lamps have an even higher efficacy, but cast a golden light that distorts colors. For this reason, HPS are often used in outdoors applications. Low-pressure sodium (LPS) lamps, which are not actually HIDs but are often compared with them, have the highest efficacy rating, but the lowest CRI rating, and are used almost exclusively outdoors.

In most cases, HIDs can be cost-effectively replaced with high-output T5 (T5HO) fluorescents, even in high-bay applications. However, this entails a redesign of the entire lighting system, and usually cannot be done in-house.

Fluorescent Lighting
Recent advancements in fluorescent lighting technology have justified the adoption of these systems in both highbay and lowbay applications. Energy-efficient T8 and T5 fluorescents have higher efficacy, better durability and longer life than their HID and T12 counterparts. Here's another benefit: fluorescents are brighter with better color densities and improve the quality of light in the work area.

Fluorescents last longer than their metal halide counterparts and do not deteriorate as rapidly. A 400-watt pulse-start metal halide lamp, for example, loses approximately 33 percent of its initial lumens by the time 40 percent of its lamp life is over, compared to only 5 percent lost in either standard T8s or T5HOs.

T12 fluorescent lighting systems have been common in lowbay facilities for some time, although they are often plagued by flickering, dim light and distracting humming. Upgrading to energy-efficient T8s or T5s can save up to 40 percent on lighting system energy costs.

In highbay facilities where HID systems are common, T5HO lamps are a good choice. Because T12 lamps have much lower lumens per watt (LPW) and perform poorly compared with T8s and T5s, they should never be used to replace HID lamps.

Additional cost savings are possible in refrigerated or climate controlled facilities because cooling loads are significantly reduced. Fluorescent fixtures and lamps generate much less heat than HIDs, which means that climate control equipment does not have to run as hard or as long to maintain correct temperature and humidity indoors. In some cases, businesses have been able to avoid costly heating, ventilation, and air conditioning upgrades by retrofitting their lighting system instead.


Optimal Ballasts that Match Control Technology
Couple fluorescent lamps with energy-efficient electronic ballasts for the most dramatic savings. Retire old magnetic and electromagnetic ballasts, and install new, high-efficiency electronic ballasts. Electronic ballasts save energy, generate less heat, have a smaller footprint, and are less of a fire hazard.

Ballasts should be matched to desired lighting controls. The availability of some features - like occupancy controls and dimmable lamps - depend on which ballast is used. Ballasts that provide these additional features have higher first costs, but achieve significantly greater cost savings through operations.

Rapid-start ballasts work best with occupancy controls and extend the usable life of lamps. Occupancy controls, whether motion sensors or CO2 sensors, ensure that lights are on only where needed. This can reduce energy and costs by as much as 60 percent, and are an excellent choice in medium-use or low-use areas.

Dimmable fluorescent lamps require dimmable ballasts. These controls work particularly well with daylighting and photosensors, allowing you to adjust the lighting system according to how much natural light is available. In California, where we enjoy abundant sunshine but high utility rates, dimmable systems coupled with daylighting apertures can achieve higher net savings over the life span of the luminaire.

NOTE: HID fixtures can be matched to occupancy controls and dimmers, but are prohibitively expensive.

Look up, look down, look all around
Besides upgrades to the actual lighting equipment, light quality can be improved by coating surfaces, like ceiling and walls, to increase reflectivity. However, work surfaces should be darker to avoid glare. This is an extremely useful low-cost measure to improve indoor lighting in terms of efficiency and quality.

What’s a Light?

What's in a light?
"Lights" as we know them actually consist of three distinct parts: the lamp (creates light), the fixture (houses the lamp) and the ballast (regulates power). Taken together, these three parts make up what is referred to as the "luminaire." A "bulb," on the other hand, is a part of a plant that grows underground!


What's the difference between fluorescent fixtures, then?
Fluorescent fixtures are named by the diameter of the lamp. For example, a T12 is a 1 ½" lamp, a T8 is a 1" lamp, and a T5 is a 5/8" lamp. The trick is to divide the number by 8 to determine the diameter in inches. Besides lamp diameter, fluorescents are sometimes further categorized by their lumen output-standard or high output (HO).


Size isn't everything
Switching from basic T8s to high- lumen T8s results in the same proportion of savings as switching from old T12s to basic T8s. Likewise, switching from magnetic ballast to electronic ones provides this same proportion of savings.

Evaluating Light Quality and Energy Efficiency

Evaluating Light Quality and Energy Efficiency

The quantity of light cast by a lamp is measured in lumens. The amount of energy needed to make light is measured in watts. To determine how energy efficient a lamp is, look at the amount of lumens per watt (LPW) it generates, known as the lamp's efficacy.

A 100-watt incandescent lamp, for example, produces about 1750 lumens, so it has an efficacy of 17.5 LPW. By comparison, a 32-watt compact fluorescent lamp produces about 1950 lumens, so it has an efficacy of more than 60 LPW. The higher the lumens per watt, the more efficacious is the lamp.

Business Examples

S. Martinelli & Company made four lighting upgrades in just one year, retrofitting highbay fixtures with T8 fluorescent lamps and electronic ballasts, and installed additional skylights that help minimize the need for electric light, and installing motion sensors that automatically turn-off lights in unoccupied areas like storage rooms, copy rooms, and hallways. Work was subsidized and assisted by programs from Ecology Action and PG&E.


Not only is the new lighting significantly more energy efficient, it also has resulted in a better indoor environment. Greg Galvin explains that, "new technology lighting makes the work environment better and brighter and requires less maintenance."

J Wine retrofitted lighting in processing areas, replacing all 70 metal halide and 35 high pressure sodium high-intensity discharge (HID) fixtures with high output T8 fluorescent lamps and electronic ballasts mounted about 20 feet from the floor. This effectively reduced each fixture from 470 watts to 220 watts. Thanks to a rebate from PG&E, energy savings paid for the investment in lighting in 18 months.


Offices and administrative spaces enjoy large glass windows that minimize the need for artificial light. When it is required, offices are equipped with T8 fluorescent indirect fixtures and fluorescent recessed fxtures. Motion sensors in the copier room shut off lights when it is unoccupied. Timers shut down outdoor lighting in the parking lot by 9 PM.


Resources

Energy Design Resources, Design Brief, Lighting

Illuminating Engineering Society of North America, Discover Lighting.

Walerczyk, Stan. Cutting Edge: Retrofitting, Relighting and Redesigning. Submitted July 26, 2003 for the World Energy Engineering Congress on November 12-14, 2004, Atlanta.

DiLouie, Craig. High/Low-Bay Applications: Fluorescent or Metal Halide? Lighting Controls Association, November 2004. (accessed March 18, 2005).

Northeast Energy Efficiency Partnerships, Design Light's Consortium. Know How: Highbay Industrial Lighting.

Northeast Energy Efficiency Partnerships, Design Light's Consortium. Know How: Warehouse Skylighting.

Wisconsin Public Services webpage Lighting: HID Versus Fluorescent for High-Bay Lighting. Includes comparison tables of color rendering and lumens per watt as well as an easy, online cost-effectiveness calculator.

Northwest Food Processors Association Efficiency Practices website offers useful information and tips for the food processing industry.