Draft · not for search
The cheapest contiguous window.
This note is unpublished. Ember EV will not offer it as a public guide until it is signed off.
The scheduler sorts the day's half-hours and splits them where one slot does not end when the next begins. Inside each unbroken run it slides a window of the length the battery needs and keeps the lowest sum. An equal sum keeps the earlier window.
Length comes from the energy still to add, the home charger kilowatts, and an 0.88 efficiency for the onboard charger. Half-hours are rounded up. If the battery is already at the target, the length is one half-hour so the app can look again later.
A personal price cap can reject that window afterwards. A leave-by time can shorten the search. The public calculator on the homepage does the contiguous search only. It says so.