Client has 3,200 kW peak demand on secondary service. Utility offered primary metering at ~$180K one-time cost (customer owns transformer) with approximately $38K/yr in savings. Payback looks like 4.7 years. At what threshold do you recommend clients make the switch?
Primary metering — when is it actually worth the switch?
Under 5-year payback is almost always worth it if the client plans to hold the property 7+ years. Key variables to pressure-test: (1) future growth in demand (if they add load, savings grow), (2) transformer maintenance cost (typically $2-4K/yr you should net out), (3) insurance adjustment for owning the transformer. At 4.7 years with no growth assumption, I'd recommend it.