Small Office
  LED case study

LED Cost Savings Summary

LED Replacement Savings

LED Break-Even Savings Chart

1 Savings-to-Investment Ratio (SIR): SIR is the ratio of savings achieved -to- the cost of an investment. A SIR of 1 or greater represents a prudent/profitable overall investment in energy efficient lighting. The higher the ratio, the more savings and profit will be realized from the investment.

2 Current Utility Rate: Utility rate is an estimated state average until more detailed information is collected. Rate may include a 3.5% total increase over 10 year period (not compounded) applied to LED lifespan, in order to estimate modest increase in retail electricity costs based on historical data (Source: U.S. Energy Information Administration).

3 Annual Carbon Emissions: Electricity sources emit 1.306 lbs of CO2 per kWh on average (Source: EPA’s eGRID emission factor)

4 LED Lifespan & Actual Usage Hours: LED lifespan ranges by facility and product and is estimated based on light operation listed above. More usage per day and year will decrease projected lifespan of lamp, while realizing a quicker payback period / break-even due to larger monthly energy savings. Lifespan of lamp type is estimated based on manufacturer's specifications and ranges from 35,000 hours - 50,000 for LED lamps.

5 Cumulative Costs: Cumulative costs assume the estimated initial cost of fluorescents lamps and LED lamps, including estimated ballast replacement costs for fluorescents using a ballast (over the 35,000-50,000 hour lifespan on LED lamps).