Module count vs. nameplate capacity: what a draw request should show

Every solar construction loan has a number that traveled from the interconnection agreement down to the draw request: nameplate capacity, usually in MWdc. It's the number everyone quotes. It is also, by the time it shows up in a monthly draw package, often the number nobody on the lender side has verified against the field.

Nameplate capacity is a derived figure. It comes from multiplying a module's rated wattage by however many modules the design calls for, then rolling in inverter and string losses to get a DC and AC rating. That math holds up fine when the module count underneath it is accurate. The trouble starts when the module count itself is a schedule estimate rather than a count of what's racked and wired at the site.

Where the two numbers diverge

An EPC's draw request typically reports percent-complete against the full nameplate target: "62% of nameplate installed," or some version of that phrasing. That percentage is almost always calculated backward from a schedule, or from the EPC's own module tally, not from an independent count of modules in the ground. Two projects can report the same percent-complete and sit in very different physical states. One might have modules racked but not strung. Another might have trackers up with no modules on them at all. Nameplate capacity alone doesn't tell a draw administrator which project that is.

Module count is the one number in the chain you can actually count. Walk a block, count the modules, and you have a fact, not a projection. A draw package that leans only on a capacity percentage is handing the lender a derived number without the underlying count that produced it.

What a draw request should show

A draw request built to withstand scrutiny, not just clear approval, includes both figures side by side:

• The nameplate capacity being claimed for the milestone.
• The module count that capacity is calculated from, broken out by block or inverter zone if the site has them.
• The date the count was taken. A count from six weeks before the draw date is not the same thing as a count from this week.
• A note on how the count was produced: an EPC site walk, a third-party inspection, or an independent count from imagery.

Leave out that last line and a lender is taking the EPC's word that the count behind the capacity number is real. On a site where other milestones have slipped before, that's the gap that turns a routine draw into a dispute about whether it should fund at all.

Reconciling the two numbers

The reconciliation itself is simple arithmetic once you have a module count you trust: modules installed divided by total modules in the design, multiplied by nameplate capacity, gives an as-built capacity figure that isn't just copied from the EPC's own schedule. The hard part is getting a module count that didn't originate with the party asking to get paid.

That's the documentation gap an independent count closes. Instead of reconciling the EPC's capacity claim against the EPC's own tally, a lender or asset owner can check it against a counted inventory of modules, tables and inverters pulled from imagery of the site, taken on the same quarterly cycle as the draw schedule. The draw package still shows nameplate capacity. It just isn't the only number in it anymore.

If your draw documentation currently stops at a percent-complete figure, ask what module count sits underneath it, and whether anyone outside the EPC has confirmed it.