Here is the simplified SQL for the query. (I have removed some fields for clarity).
SELECT
POPData.[PSPO], POPData.[kW saved winter (Est)], POPData.[kWh Summer (Est)], POPData.[kWh Winter (Est)],
POPIncentives.VerifiedkWWinter, POPIncentives.VerifiedkWhSummer
FROM POPData LEFT JOIN...