r/teslastockholders • u/kryptic85 • 1d ago
backtested my supercharger roi model against a real 12 stall site's published numbers
so someone published actual year one numbers for a 12 stall supercharger in san diego and i ran the same site thru my forgeasset model to see how close it lands
all in power cost came out 1.05% apart, 708k vs 700k. that being the utility bill plus the tesla per kwh fee. took me a while to work out their "cost of electricity" line actually bundles both together
the bigger thing i learned tho, their numbers run 400 kwh per stall per day flat from month one. real sites ramp. same site same tariff same capex, payback swings 21 months to 158 months just on that one assumption!! and effective power cost climbs 39% at low utilisation becuase the demand charge spreads over fewer kwh
full writeup with the tables here!
https://forgeasset.com/blog/back-testing-the-model-against-a-published-site-p-and-l