Understanding the cost of outdoor lighting electricity
In commercial buildings, outdoor luminaires often have long operating plans. For example, a lighting system that operates 12 hours a night accumulates 4,380 hours of use per year. When using older and less efficient types of lamps, the electricity bill can be very high.
Suppose you have 100 parking lights with halogen bulbs that consume 460 watts. Their total consumption is 46,000 watts – 46 kilowatts.
- If these luminaires are used 4,380 hours / year, they consume 201,480 kilowatt hours.
- According to US Energy Information Administration, the average commercial tariff in the country is 11.57 cents / kWh (as of July 2021).
- At this price per kWh, 100 halogen lamps have energy costs $ 23,211 per year.
These are estimated operating costs based on the average US commercial tariff. However, the electricity bill may be much higher in countries with expensive electricity. Consider New York and California, where average commercial tariffs are 18.36 cents / kWh and 20.88 cents / kWh.
|State||Commercial electricity tariff||Annual operating costs with MH
(201,480 kWh / year)
|US average||11.57 cents / kWh||$ 23,311|
|New York||18.36 cents / kWh||$ 36,992|
|California||20.88 cents / kWh||$ 42,069|
In general, a 460W halide lamp can be replaced with the equivalent of a 150W LED, which reduces power consumption by 67 percent. In this case, the total annual consumption would fall from 201,480 kWh to 65,700 kWh, which is reflected much lower electricity bill.
|Annual operating costs with
LED (65,700 kWh / year)
|US average||11.57 cents / kWh||$ 7,601||$ 15,710|
|New York||18.36 cents / kWh||$ 12,063||$ 24,929|
|California||20.88 cents / kWh||$ 13,718||$ 28,351|
Assuming the cost of upgrading the LED is $ 600 per luminaire, the total budget is $ 60,000. Based on electricity savings alone ($ 15,710 per year), the payback period would be 3.8 years. However, we must also consider replacing lamps, which are very expensive in the case of parking lights.