Cannabis Facility Energy Cost Calculator

What each input means

State sets the default cents-per-kWh rate. The dropdown pulls the EIA average commercial price for that state, updated from Table 5.6.A [eia-epm-5-6-a]. Illinois, for example, averaged 14.53 cents/kWh in June 2026. That figure blends every commercial customer in the state, so your all-in delivered rate may differ.

Connected load running at once is the sum of equipment that can be on during your worst simultaneous interval, in kilowatts. For cultivation, lighting dominates: the Northwest Power and Conservation Council found lighting was 66 percent of electricity use across surveyed producers [nwpcc-cannabis]. Add HVAC and dehumidification that ramp when lights are on. A 10,000 sq ft flowering canopy under top-bar LED commonly lands between 300 and 600 kW depending on fixture density and HVAC strategy.

Hours per day is how long that load runs at full draw. Veg rooms often run 18 hours of light; flower rooms 12. HVAC and dehumidifiers typically run longer than the photoperiod, but this field assumes one average run time for the whole connected load. If you want a tighter number, run the grow-light wattage converter for lighting only, then add HVAC separately.

Days per month defaults to 30. Use your billing cycle length if you know it.

Demand charge is the dollar-per-kW rate from your tariff. NREL's survey of more than 10,000 commercial tariffs found demand can account for 30 to 70 percent of a commercial bill [nrel-demand-charge-survey]. The default $12/kW is a placeholder. Replace it with the figure on your bill or tariff sheet.

Your actual all-in rate (optional) overrides the state average when you know your blended supply-plus-delivery cents-per-kWh. Leave it at zero to use the EIA figure.

The math step by step

The calculator uses three formulas:

Energy cost here is a single blended rate. On a real commercial utility bill, supply and delivery are separate lines, and time-of-use schedules change the effective cents per kWh by hour.

Demand is modeled as a flat monthly charge on the full connected kW. Many tariffs instead bill the highest 15- or 30-minute interval in the month, which may be lower than nameplate if not every circuit is on at once. Use the demand charge estimator when you have a measured peak from your bill.

Assumptions baked in

• The connected load runs at its entered kW for every hour you specify. Partial loads, dimming, and staged HVAC are not modeled.
• One flat energy rate applies to all hours. No on-peak or off-peak split.
• Demand is one line item with no ratchet, no seasonal multiplier, and no distribution-vs-transmission split.
• State averages include customers far smaller than a grow. Your effective rate may sit above or below the EIA commercial average depending on rate class and contract type.

Limits of this tool

This is an orientation estimate, not a quote or tariff audit. It does not include customer charges, reactive-power penalties, taxes, renewable surcharges, or demand-response credits. It does not tell you whether you qualify for a competitive supply contract; use the state deregulation eligibility checker for that.

For a facility-level benchmark against industry data, compare your result to kWh per square foot benchmarks. If demand is a large share of the total, read demand charges explained before changing equipment or schedules.

Worked scenarios by facility type

The defaults in the calculator are cultivation-oriented. Adjust inputs when your facility type differs.

Indoor flower canopy (10,000 sq ft). Assume 400 kW connected load when LED top bars, dual-stage HVAC, and dehumidifiers can run together during photoperiod. At 18 hours per day for a veg-heavy year averaged to 14 hours, 30 days, 14.53 cents/kWh, and $12/kW demand, monthly energy is about 168,000 kWh and $24,410 in energy charges. Demand at 400 kW adds $4,800. Real peaks may be lower if not every circuit starts in the same interval.

Greenhouse with supplemental light. Connected load might be 150 kW with 10 hours of supplemental lighting in winter averaged to 6 hours year-round. Same rate yields roughly 27,000 kWh and $3,923 in energy before demand. Greenhouse intensity per square foot is lower in published surveys [nwpcc-cannabis]; dollars still scale with tariff.

Hydrocarbon extraction lab. Chillers and recovery units might sum to 80 kW running 16 hours daily. That is 38,400 kWh per month at the example rate, or $5,579 energy. Peak kW may track chiller startup more than lighting. See extraction processing facility energy loads for load breakdowns.

Dispensary retail. Twenty kW of HVAC, lighting, security, and refrigeration running 14 hours hits about 8,400 kWh per month, or $1,221 energy at 14.53 cents. Many dispensaries sit on non-demand rate classes; set demand to zero if your bill has no kW line.

How to calibrate connected load without a single meter reading

Walk your panels and schedules when you do not have an engineer's load letter.

1. List every circuit that can be on during worst-case overlap.
2. Use nameplate or spec-sheet watts per fixture, including ballast or driver loss.
3. Add HVAC and dehumidifier nameplate for units that start with lights.
4. Divide total watts by 1,000 for kW.

Cross-check against twelve months of bills: monthly kWh divided by (hours per day times days) should land near average kW. If average kW is far below connected kW, your hours field is too high or not everything runs together.

The grow light wattage to cost converter isolates lighting kW when you know fixture count and watts per lamp.

When the estimate says your bill should be lower than reality

Common gaps between this calculator and a real invoice:

Supply and delivery are blended in the EIA default. If you shop supply separately, enter your delivered cents per kWh from the bill total divided by kWh.

Using results in procurement conversations

Suppliers quote against historical usage, not nameplate load. Bring trailing twelve-month kWh and peak kW from bills when you request pricing. This calculator helps you sanity-check whether a supplier's implied annual cost matches your load assumptions before you sign.

If energy plus demand from the tool is already below your actual bill, the gap is probably riders, taxes, or a supply rate above the state average. Run the supplier contract comparison worksheet when you have offers.

If the tool exceeds your bill, you may have overstated connected load or demand rate. Lower inputs until energy kWh matches one month times twelve, then revisit demand.

Seasonal and expansion notes

Indoor flower schedules change kWh through the year even when nameplate load is flat. Veg rooms at 18 hours and flower at 12 produce a sawtooth monthly kWh pattern. This calculator uses one average hours field; run separate passes for veg and flower if they are on different meters.

Adding rooms mid-year increases both kWh and peak kW. Bandwidth clauses in supply contracts penalize load growth beyond forecast. Model expanded kW here before you sign a fixed volume deal.

Cooling degree days affect HVAC kWh but not lighting kWh. The tool does not weather-normalize. Compare summer and winter bills separately when tuning inputs.

Quick sanity checks before you trust the output

Divide monthly kWh by billed peak kW when you have a real bill. If the ratio is below 100 hours equivalent, peak kW may be overstated in the demand field or kWh understated in your bill copy.

Multiply energy cost plus demand cost by twelve and compare to last year's total utility spend excluding taxes. Within 15 percent is reasonable for a first-pass model. Larger gaps mean riders, supply contract premiums, or gas charges are material.

Log results in a spreadsheet with date, inputs, and outputs so you can rerun when rates change or rooms expand. Procurement teams reuse the same template at renewal.

Case studies on this site show how tariff-specific demand restructures change totals without changing kWh. See Illinois craft grower demand charge restructure for a worked utility-side example paired with supply shopping.