Energy Cost

What it does

A time-of-use electricity cost calculator for grow lighting. The lighting load is one 600 W fixture; you choose the utility rate profile, the lights-on and lights-off hours, and an optional HVAC load multiplier.

When to use it

Use it to see how a lighting schedule falls across a utility's peak and off-peak hours and what that does to daily, monthly and yearly cost. The preset rates are representative regional structures; choose Custom to enter your own $/kWh.

How it calculates

• Total load (kW) = fixture kW × (1 + HVAC multiplier when enabled)
• Each lights-on hour is charged at its time-of-use rate. Monthly cost = daily × 30 and yearly cost = daily × 365
• Demand charge = peak kW × the profile's $/kW rate
• Savings opportunity = lights-on peak hours × kW × (average peak rate − average off-peak rate) × 30

What you enter

Utility Provider(preset or Custom)

Your average rate($/kWh, Custom only)

Lights On(hour, 0–23)

Lights Off(hour, 0–23)

Include HVAC cooling load

HVAC Load Multiplier(0–1)

What you get

Daily Cost($)

Monthly Cost($)

Yearly Cost($)

Demand Charges($/month)

Potential Savings Opportunity($/month)

Time-of-Use Rate Schedule(24-hour)

Load summary(kW)

PDF report

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