Use consumption shares, not clock-hour shares
A period covering one-third of the hours does not necessarily contain one-third of your kWh. Cooking, heating, cooling and EV charging can cluster at different times. Use interval data or bill-reported period totals where available. Treat equal-share defaults as illustrations rather than observed behavior.
Map each plan separately
Two tariffs can define peak, weekend and overnight periods differently. A usage distribution suitable for one cannot be copied blindly into another. Include holidays, seasonal schedules and the time zone used by the meter. The current workbench accepts manually entered shares; it does not automatically align interval data to every tariff calendar.
Look beyond the overnight headline
Compare the standing charge and prices outside the discount window. Consider how much load can actually move without affecting safety, comfort or equipment needs. An EV can be flexible, while cooking or space heating may not be. The tool should show the full model even when the overnight rate looks attractive.
Recheck after a schedule change
A change in work hours, household members or charging location can alter the distribution. Keep both the source tariff and the usage-share assumptions with your worksheet, then revisit them using a comparable period. Modeled savings are not proof of a future reduction.
HAUSE Energy editorial team · reviewed 2026-10-26. Calculation and coverage limits are documented in the methodology.