Notes on EV-charging site economics — tariffs, incentives, cost stacks, and how the underwriting engine models them.
A charging site sells the kWh cars receive but buys the kWh the utility meters — and the gap between the two runs through almost every line of the cost model. What the loss factor is, where it shows up, and what a 12% default does to a year of numbers.
Since Tesla opened the Supercharger for Business program, property owners and businesses can purchase and own Supercharger sites. What the path from application to energization looks like, how the ownership model works, and what an eight-stall site costs and earns under the model's default assumptions.
What the national economics map shows when effective electricity cost and Supercharger density are read together: the cheapest priced territories carry single-digit station counts, and the densest territory pays close to double the cheapest.
Electricity has two prices: one for how much you use, one for your single highest 15-minute spike. For DC fast charging the second one decides the outcome — and it varies 10× by utility.
Washington, Ohio, Utah, New Hampshire, and Kentucky join the covered set — and each forced a cost the model could not express before: sales tax on installation labor, a percent-of-revenue charging tax, and a state income tax on the entity itself.
Wisconsin, Iowa, Indiana, Louisiana, and Nevada join the covered set — and the pre-seed verification pass moved real numbers in three of the five states before they shipped.
What a DC fast-charging site actually pays for demand in Montana, Idaho, Kansas, Nebraska, the Dakotas, and Wyoming — seven filed rate designs, from a plain per-kW charge to caps that erase the demand line entirely.
New Mexico, Oklahoma, Alabama, and Missouri join the covered set: five of eight new filed tariffs bill no demand charge at all, New Mexico's clean-fuels market pays the site per kWh, and Oklahoma pairs its EV rate with a 3¢/kWh charging tax.
The five numbers that answer it — payback, NPV, IRR, cash-on-cash, upfront capital — and the handful of inputs that actually move them.
Every cost line the underwriting engine models for a Supercharger for Business site: hardware, install, utility upgrades, electricity under 85 filed tariffs, rent, taxes, and hidden fees.
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.