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For people electrifying facilities the grid wasn’t ready for.

FEATURED · FIELD GUIDESep 13 · 7 minWhat is NEC 220.87?NEC 220.87 is the method for establishing the existing load on a service or feeder from what it actually drew: the maximum demand over 12 months of utility records, or a 30-day recording where those are not available, taken at 125% and added to the new load against the rating. In the 2026 edition the same method is numbered 120.87.Read the guide →

THE EVIDENCE12 months, or 30 daysTHE MARGIN× 125%IN NEC 2026120.87

JURISDICTIONSep 13 · 3 minDoes a load calculation need a PE stamp in California?It depends on who is installing the work and what the authority requires. Electrical engineering is a practice act in California, a licensed contractor may design only the electrical work it installs itself, and the authority reviewing the permit sets whether the calculation has to be sealed. The NEC itself requires no stamp.JURISDICTIONSep 13 · 2 minIs it NEC 220.87 or 120.87 in California?It is 220.87. The 2025 California Electrical Code, Title 24 Part 3, is based on the 2023 NEC and took effect on 1 January 2026. The 2026 NEC renumbers the method to 120.87, and that number applies in California only when the state adopts the 2026 edition through a future code cycle.JURISDICTIONSep 13 · 5 minHow do load studies work in California?California is on the 2025 California Electrical Code, based on the 2023 NEC and in force since 1 January 2026, so the measured-load method is section 220.87. Electrical engineering is a practice act there, a licensed contractor may design only what it installs itself, and all three investor-owned utilities run service upgrades under Electric Rule 16.FIELD GUIDESep 13 · 3 minWhat is demand on a commercial electric bill?Demand is the highest rate at which the facility drew power during the billing period, in kilowatts, averaged over an interval the utility sets, commonly 15 minutes. Consumption is the energy used over the whole period, in kilowatt-hours. A load study needs demand, because the peak is what sizes a service, and a bill that shows only kilowatt-hours cannot supply it.FIELD GUIDESep 13 · 3 minWhat is the difference between a load calculation and a load study?A load calculation establishes the existing load from what could run, using the demand factors in Article 220. A load study establishes it from what the facility actually drew, using NEC 220.87. Both are recognised by the code. The study usually shows more room, because the calculation assumes far more of the equipment runs at once than ever does.FIELD GUIDESep 13 · 3 minHow long does a load study take?3 days from 12 months of utility records, 3 to 5 days with the permit set, and about 5 weeks where the panel has to be metered, because 30 days of readings are the evidence. The turnaround is published and it is the same for every customer.FIELD GUIDESep 13 · 3 minDoes a load calculation need a PE stamp?The NEC does not require one. Whether your submittal needs a Professional Engineer's seal is set by the authority having jurisdiction and by state licensing law, so it depends on where the facility is and what the permit is for. Ask the authority before you submit.FIELD GUIDESep 13 · 3 minLoad study or service upgrade?Get the load study first. It tells you whether the upgrade is needed at all, and if it is, the study becomes part of the upgrade application. It is the cheaper and faster step, and it is never wasted.FIELD GUIDESep 13 · 3 minHow much does a load study cost?A sealed commercial load study is $1,800 from 12 months of utility records, or $3,300 with 30 days of on-site metering. A permit package is $3,600 or $5,100. The prices are published and fixed before the work starts.

Holding a quote like these?Two minutes of taps scopes your study and shows the fixed price.

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