Client in Bakersfield had PG&E replace mechanical meters with AMI units. New meters started recording reactive power demand charges that never appeared before. Old Westinghouse mechanical meters couldn't measure vars. $8,400 in new monthly charges.
PG&E smart meters reading reactive power wrong
That's not an error, that's a feature! Smart meters can measure reactive power where mechanical meters couldn't. Check the tariff - PG&E probably always had var charges but couldn't bill them with old meters.
Same thing happened with Xcel Energy in South Dakota. Client thought it was an error but Schedule A-57 had reactive power charges the whole time. Old meters just couldn't read them.
This is why I always review tariff schedules during meter upgrades. Utilities often have charges they can't collect until they get smart meters installed. Power factor correction equipment might be worth installing.