A large part of our customers’ success has been from showing building owners and operators how reducing their lighting costs can have a big impact on their bottom line. The first step to accomplishing this is a Lighting Audit to help identify the best lighting technology for each application that will yield maximum energy savings for the customer.
What Is a Lighting Audit?
A Lighting Audit is an onsite walkthrough of an existing facility to document the current lighting conditions and determine where energy saving changes can be made. It can be conducted for both exterior and interior spaces, and involves collecting four main types of information: general, lighting, occupant, and financial.
General information includes floor plans and ceiling plans that show current fixture locations. Room dimensions, as well as ceiling heights are also documented. Any future plans for renovation are also collected, if available.
Lighting information for each area being considered is also collected. This includes information such as the:
- Number of fixtures
- Type and size of fixtures
- Number of lamps per fixture or ballast
- Type of lamps or ballasts
- Fixture wattage
- Tasks performed in the space
- Hours of operation in the space
- Height at which tasks are performed
- Availability of natural daylight
It is also important to know how occupants feel about their current lighting system, as their insight can provide information to fill the gaps a physical inspection cannot determine. This step usually involves interviews or surveys, where the auditor asks the regular occupants of each space to reflect on how the lighting currently affects them. Questions can include whether occupants are experiencing glare on their computer screen, if they find the lighting too dim when they work at their stations or whether it is too bright (especially in areas where there is natural light) during the day.
With the physical space and how users react to it documented, the last step of a Lighting Audit is to collect financial information. Knowing the average charges for electricity (kWh) and demand (kW) is important to calculating current operating costs and the eventual long-term savings gained from replacing everything with energy-saving fixtures.
How to Conduct a Lighting Audit: Our 6-Step Checklist
Identify each space. Is it an office? Warehouse? Retail showroom? Parking lot? Note any special conditions such as windows or skylights.
Specify each existing fixture type, noting each one’s:
- The number of hours used per week
- Additional notes such as any existing controls/sensors, mounting height or special usage conditions
Calculate the approximate Annual Burn Hours (the number of hours fixtures in a space are turned on per year).
Determine the fixtures’ Kilowatt (kW) rate (how many Kilowatts the fixtures use).
Find the average Kilowatt per Hour (kWh) rate based on the customer’s three most recent utility bills.
Calculate the existing energy expense of all fixtures.
The end result is the facility’s current lighting cost. Having this number allows you to show how your recommended energy-efficient replacements will drastically lower their month-to-month operating expenses.
Lighting Audit Tips
While a Lighting Audit is straightforward, every space can be different. The following is our list of tips to consider for achieving the most accurate assessment:
- Accurate system wattage. Fixtures are often suspended high in the ceiling, but knowing each one’s wattage is crucial to the overall calculation. Don’t assume system wattage is the same for every fixture just because they look the same.
- Space usage seasonality. A space can be used differently in different times of the year. A warehouse may be used for packing, storing, and shipping during peak season–but is then re-configured for storage only when off-peak. Knowing this not only changes the annual burn rate and energy expense; it can also affect the new fixtures that are proposed.
- Room surface reflectances. Bright surfaces in a room reflect light, making things brighter while dark areas absorb light, requiring more lumen output to sufficiently illuminate a room. Therefore, it is important to note the current color of floors, walls and ceilings and know if there are any planned changes.
- Opportunity for controls. Understanding how each space is used allows you to suggest the use of simple controls that detect motion, perform daylight harvesting functions or work on a timer, providing further savings opportunities.
- Maintenance (or lack of). Replacing current fixtures and lamps with those that are long-life will result in maintenance savings, particularly in areas with difficult-to-access fixtures. Make a note of this major selling point.
- Space dimensions matter. Having the accurate dimensions of the space (length in feet, width in feet, ceiling heights in feet and areas in square feet) is important to a successful audit. Be aware that renovation work could have been performed since the original building was built so the floor plan you have may not reflect the current fixture layout in the ceilings.
- Don’t manipulate hours to get meet ROI targets. We have seen some auditors in the past bump the hours of operation of fixtures in order to inflate the cost of system operation to reduce the payback period. Avoid this because the customer will eventually see that their payback period is longer than your proposal (especially since IoT is growing in popularity, and the ability to measure exact output is now available); this could seriously affect your long-term relationship with them.
Lighting Audits aren’t complicated; but they do require a degree of knowledge and attention to detail. Doing them right is the first step to providing your customers with a cost-saving solution for their business. At Premise, we offer Lighting Audits as a part of our Partner Services to our distributors and their electrical contractor partners. Contact us if you need help!