Charging to Minimize Cost



Offer an option that would figure out the cheapest home charging cost. It would include outside temp, utility time-of-day pricing when I expect to leave, and other considerations that may lower the cost.


I guess that internal resistance varies non-linearly with temperature, voltage (SOC), and current. Conditioning the battery to accept charge likewise varies with ambient temperature and wind, heat gain from charge inefficiency, maybe battery health or age, and probably other stuff. It’s wakeful state when charging draws a trickle. Does SOC affect the battery discharge rate while the car sleeps? Then factor that in.

I’d prefer the car to continuously vary the current as conditions change to charge as cheaply as possible, without exceeding the set current limits.

I’d like, on arriving home, to set anticipated departure time and trip distance and let it do the math. Departure might be tentative/definite, or a continuum between those extremes. Choosing definite should allow the car to charge to 100% just in time for launch.

It might use an internet provided forecast to time it’s charging and maybe even adjust the charge level accordingly. It can quickly learn how my garage moderates the outdoor temperature.

I’d like for it to allow for energy management programs like “off-peak”, “dual fuel”, or night storage heating (start time but add stop time). These load switching programs cause the car to sleep, and I wake up for work to a third charged battery. If I select ‘switched supply’, it should periodically wake to sample the charger and it should allow for an hour or two interruptions.

A price schedule could be factored in.

Load coordination could be considered so it doesn’t blow the main breaker when I usually take my sauna and the heat pump kicks on. That could be simply defining curfews for reduced charge limit or by monitoring your household meter via the internet or a Bluetooth device. I know it’s far out. It would be so cool and only involves programming.



lightly edited by moderator
Category: CY3XS Applies to:
     Created 24-Oct-2019

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Use your home automation system to implement this. Of course, you’ll have to set up the links to data sources and do the programming, but you’ll save thousands of pennies per year.
    Created 1-Feb-2020