Lighting Upgrade Payback Estimator

Energy Standards

Average annual energy rate: $/kWh

Average annual demand rate: $/kW

Annual operating hours:

Lighting Specification

Installation cost

Cost of new luminaire (each): $

Labor cost to install new luminaire (each): $

Project Payback and Savings

Calculate payback and savings

Instructions

This calculator will estimate the savings associated with a lighting upgrade in your facility. The calculator accepts inputs based on the current lighting in your facility, the proposed lighting system that you are analyzing, and your utility costs. The calculations will show the annual costs of your current system, the proposed system, the savings for the project, and the simple payback period based on these values.

Inputs

• Average annual energy rate - the 12 month marginal energy cost per kWh of electricity used in your facility. If you don't know this number, it can be calculated from previous bills or for a less accurate estimate you can enter an aggregate energy cost in this field.
• Average annual demand rate - the 12 month average demand charge per kW peak for your electricity. If you don't know this number, it can be calculated from previous bills or for a less accurate estimate you can enter zero (0) and use an aggregate energy cost.
• Annual operating hours - the number of hours the lights are on each year. If you are considering using occupancy sensors to reduce your lighting operation hours, please see our occupancy sensor calculator.
• Luminaires - the number of lighting fixtures to be considered in this analysis. The proposed system may or may not have the same number of luminaires as the existing system.
• Lamps per luminaire - the number of light bulbs in each fixture.
• Lamp wattage - the wattage for each individual bulb.
• Ballast Multiplier - the percentage of lamp wattage that is consumed by the ballast. As a rough estimate, use 10% for magnetic ballast and 2% for electronic ballast. If you know the exact wattage use by your ballast, feel free to use the exact percentage, or add the ballast wattage in with the bulb wattage.
• Cost of new luminaire - the purchase price for each new fixture, including bulbs.
• Labor cost to install new luminaire - the installation cost for each new light fixture.

Outputs

• Annual operation cost of current lights - the total annual cost, based on energy and demand inputs, for the existing lighting system. If you used the less accurate aggregate energy cost, this cost may include charges that cannot be reduced (e.g. customer charges).
• Annual operation cost of proposed lights - the total annual cost, based on energy and demand inputs, for the lighting system that is being analyzed. If you used the less accurate aggregate energy cost, this cost may include charges that cannot be reduced (e.g. customer charges).
• Cost to install proposed lights - the total cost, based on luminaire cost and labor costs, to install the lighting system that is being analyzed.
• Annual energy savings - the annual number of kWh that will be saved by installing the new lighting system.
• Monthly peak demand reduction - the peak demand reduction, in kW, of the proposed system versus the existing system.
• Annual energy cost savings - the annual reduction in energy cost of the proposed system versus the existing system. [(old kWh - new kWh) * energy rate]
• Annual peak demand cost reduction - the annual reduction in demand charges of the proposed system versus the new system. [(old peak - new peak) * demand rate * 12 months]
• Annual total cost savings - the annual energy cost savings plus the annual demand cost savings.
• Simple payback - the number of years required to accumulate enough savings to pay for the installation of the new system.

Contact the Arkansas Industrial Energy Clearinghouse if you need assistance with this calculator.