Free tool
Free meter data checker
Check a site's interval meter data before a battery study: gaps, duplicates, daylight saving time, kW vs kWh, registers, spikes and coverage. Free, no account, nothing uploaded.
Short answer: a battery study needs 12 months of 15-minute data with at least 90 % of the intervals measured. Check that the values are kWh per interval (not kW or a meter register), that daylight saving days have 23 and 25 hours, and that no gap or spike will size the battery for you.