AES Environmental Consulting

Energy-Efficient Lighting Solutions

In late 2009 aes started to market energy-efficient lighting solutions as a part of our strategy to help our clients deal with their environmental challenges. The rising costs associated with illuminating a broad spectrum of commercial properties can have a significant financial impact for many businesses. And the first-generation energy-efficient lighting solutions tended to be manufactured using materials that have a significant environmental impact during their normal operations, and at the end of their life cycle when the fixtures require disposal.

The balance of this document is devoted to providing background information regarding the benefits associated with the use of energy-efficient lighting solutions.

If reducing your energy consumption and maintenance costs sounds like an attractive concept, give us a call. We’ll be glad to work with you to develop a strategy that best meets your unique circumstances and goals.

Why Upgrade Lighting – The Financial Case

• There are numerous financial benefits for businesses who upgrade their commercial or industrial buildings with new energy efficient lighting systems
• Outdated lighting in a large commercial or industrial building can be responsible for up to 80% of the onsite electricity usage
• As an pure financial investment, energy saving lighting provides a quick, guaranteed return – 18-30 months is typical, with less than 18 months being possible
• Availability of rebate and credit programs from many power companies and governmental agencies to offset a significant portion of your up-front capital investment
• Many indirect financial benefits including reduced lighting maintenance costs, better productivity in improved working conditions, avoiding financial penalties of new stringent environmental regulations etc…
• The following is an overview of environmental benefits associated with the upgrade …
• A business is able to demonstrate its concern for the environment and a carbon reduction strategy to supply chains and customers. New lighting has the advantage of being a very “visual” demonstration of an onsite energy reduction initiative
• New energy efficient, long life lamps require much less frequent replacement, resulting in less waste requiring specialized disposal. This simplifies a business’ efforts to ensure compliance with ever tighter environmental regulations (e.g. the Waste of Electronic and Electrical Equipment initiative – currently confined to EU market – requiring specialist disposal)
• The opportunity to realize a extremely quick return on investment ensures that the installation of new lighting is a convincing first step as part of a wider sustainability initiative or environmental strategy for a business

Key Features of Energy-Efficient Light Fixtures

• Reduced power (electricity) consumption of up to 80%
• Reduced routine maintenance costs: 50,000 – hour life cycle for LED lights, and 100,000 – hour life cycle for induction lights
• Reduced heat loads in buildings
• Extended warranty – up to a 5-year warranty for LED lights, and up to a 10-year warranty for induction lights
• Available in high-bay, low-bay, wall pack, street light, and floodlight configurations

Sample Specifications

 

Some Technical Information that Explains why this Works – Lux, Lumens & Watts…

This section is intended to help you understand what the expressions “lux” and “lumens” mean and how they relate to the power consumption & light output of energy-efficient commercial & industrial light fittings.

Lux – a standardized unit of measurement of light intensity (which can also be called “illuminance” or “illumination”). As an example for reference purposes, 1 lux is equal to the illumination of a surface one meter away from a single candle. Some further examples of settings with the average recommended illuminance is measured in lux is shown below:

• Outdoor average sunlight ranges from 32,000 to 100,000 lux
• Warehouse aisles are lit to a range of 100 to 200 lux
• A brightly lit office environment requires approximately 400 lux of illumination
• At sunset and sunrise (with a clear sky), ambient outdoor light is approximately 400 lux
• Typical public building corridors are considered to be adequately lit at approximately 100 lux
• Moonlight represents approximately 1 lux

Lumen – a standardized unit of measurement of the total amount of light (packets or quanta if you want to get really technical!) that is produced by a light source, such as a bulb or tube. This total amount of light may also be referred to by lighting engineers as “luminous flux”. Some examples of total light output from common commercial & industrial light sources are given below, measured in lumens (NOTE: these are sample figures for example purposes only – the actual output can vary significantly from installation to installation):

• high bay warehouse lighting: 38,000 lumens output with a 400W Metal Halide lamp
• street/parking lot/area lighting – 12,000 lumens output with a 150W High pressure sodium bulb
• general task lighting applications: 1,700 lumens output with a 100W Incandescent bulb
• office ceiling lighting – 1,600 lumens output with a 32W T5 or T8 Fluorescent tube

One lux is defined as being equivalent to one lumen spread over an area of one square meter, or to put it another way – a measurement of lux (light intensity) tells you how many lumens (total light output) are required to effectively illuminate the area you are trying to light.

• 1,000 lumens, concentrated into an area of one square meter, lights up that square meter with a light intensity (illuminance) of 1,000 lux.
• The same 1,000 lumens, spread out over ten square meters, produces a light intensity (illuminance) of only 100 lux.

Therefore, lighting a larger area to the same measurement of lux requires a larger number of lumens – which is usually achieved by increasing the number of light fixtures (and the power consumed).

The relationship of lumens & watts

Wattage, measured in Watts, is the power (electricity) required to operate a light fitting. It refers to the total electricity that is consumed which will include:

• The heat generated by the light source
• Operational aspects depending on the type of lighting device (mechanical consumption)
• The energy of the light emitted from the bulb or tube

So the rated wattage of a light source refers to the entire power consumed to drive the source and lumens only refers to the light output of that source.

A light engineering term exists for the measurement of the rate at which a lamp is able to convert electrical power (watts) to light (lumens) – this is referred to as “luminous efficacy” – and is expressed in lumens per watt (LPW) or sometimes lumens per circuit Watt.

Some examples of luminous efficacy and other performance criteria are given below (from www.energysavers.gov)