The ForgeAsset blog
Tariffs, demand charges, incentives, and cost stacks — what each one does to a site, priced the way the underwriting engine prices a real address.
Three standard metrics, one pair of hypothetical charging sites, three different rankings. What each number actually encodes, why they diverge, and why a model reports all of them instead of picking a winner.
methodology
Filed tariff sheets decide a charging site's biggest operating cost, and they don't read like price lists. The six fields that matter, the riders that hide in the back pages, and real examples from 86 modeled schedules.
methodology
A developer published year-one figures for a 12-stall San Diego Supercharger. Normalized to identical throughput, our tariff-derived cost of delivered power came within 1.05% of theirs — and here is exactly what that comparison does and does not depend on.
returns
Clean-fuel credits are quoted gross, at a headline rate per kWh. Between the quote and the bank account sit an aggregator commission, a registration gap, and a payment lag that together take roughly a fifth of the line.
methodology
A grant is not a discount. It arrives mid-year, it can reduce the loan or the depreciable basis or both, and each of those choices changes the returns differently — here is how the cash flow actually treats it.
costs
The federal charging-property credit terminated for property placed in service after June 30, 2026. What that means for sites already energized, for sites still in construction, and for the basis-reduction rule that outlives the credit itself.
costs
Pricing a charging site at one blended $/kWh is the most common shortcut in Supercharger pro formas. Across the filed tariff library the true figure varies 8.5×, and demand charges are more than 40% of the bill in most territories.
costs
Hardware, install, contingency, and the one-time sales tax — priced per stall and totalled for 4, 8, 12, and 20 stalls, with the state-by-state tax spread that moves the same build by six figures.
costs
California's biggest utility bills DC fast charging through subscription blocks instead of a classic demand charge. What BEV-2-S actually charges, how the pieces interact, and what the model does with each one.
methodology
Sales tax on the build, property tax on the equipment, per-kWh excise on every sale, and percent-of-revenue levies — the four tax families a charging site pays before income tax enters the picture, with the filed rates the model carries.
Model a real site
The scenario wizard runs the same engine described on this blog: enter an address, stall count, price, and your assumptions, and it computes the payback, NPV, IRR, breakeven utilization, and the full 15-year cash flow for that combination.