Load form and load letter

A load form is a template the utility publishes and the applicant fills in. A load letter is a signed statement from the applicant's side carrying the same kind of figures, typically written by the project's electrical engineer or electrical contractor. The names are not standard. National Grid titles its form a Load Sheet. Central Hudson’s undated service delivery process asks for a load letter to accompany the application, with a breakdown of estimated electric load for each structure on the site.

National Grid’s Load Sheet says the utility designs and builds the requested electrical system from the loads provided, so the figures carry weight. The following hypothetical example illustrates the fields; the figures are assumptions, not a design assessment.

• Service size. 1,200 amps, 480 volts, three-phase, the stated equipment rating, not a measure of available utility capacity.
• Equipment by type, each in kW with an estimate of hours of use per year. Inside lighting 120 kW. Air conditioning 300 kW. Additional equipment, which here holds the dock and conveyor equipment at 250 kW and the forklift chargers at 180 kW. Motors have their own lines in horsepower.
• Total connected load. 850 kW, the sum of the lines above (120 + 300 + 250 + 180).
• Total diversified load. The form does not define the term on its face. Confirm the utility’s intended calculation and document the operating assumptions. An independently estimated coincident peak is useful context, but should not be entered as diversified load without checking the requirement.

The service rating converts to about 1.0 MVA and the load lines are in kW. These describe different quantities; a power-factor conversion does not turn the service rating into spare capacity. See what a building’s electrical service rating tells you.

The Load Sheet's fields do not include a date. A hypothetical phased schedule (200 kW in January 2028, 350 kW in July 2028, 520 kW in March 2029) would typically go in a load letter or a covering message. A load letter for the site would restate the same figures in a few paragraphs, give the schedule, and carry a signature and date, which lets the utility see who made the estimates.