@yingc125, wow, that’s a significant difference. A few questions related to potential sources of differences.
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Do you have a smart meter or does your utility rely on human meter readers ? Can you get a more detailed view of daily / hourly usage ?
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Are you sure that Sense CTs are measuring exactly the same load as the meter ? Several users with initial big discrepancies missed a parallel circuit branch and subpanel that diverged after the meter, but before their main panel. Not as likely if Sense has truly found ever major device in your new unit - in other user cases the other branch powered things that the users had forgotten about - golf cart charger, what they thought to be non-functional heater, common laundry room.
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Unlikely, but you don’t have 3-phase wiring vs standard US split phase service ? The only reason I mention that is that larger condos do employ 3-phase wiring.