Frequently asked questions

OverflowEV is a cloud platform that automatically charges your electric vehicle using excess rooftop solar. It watches your home energy flows, decides when spare sunshine is available, and starts or stops charging so more of your solar stays on-site instead of being exported cheaply to the grid.

Most households earn a low feed-in tariff for exported solar, then pay a much higher rate to buy electricity back for EV charging. OverflowEV prioritises charging from excess solar so you use that energy in the car instead of exporting it, reducing grid charging costs day after day. Many customers save over $30 per week, depending on solar size, driving, and tariffs.

Solar is recommended for the biggest savings. Without solar, scheduling and vehicle control features still work, but you won’t get the same Free Solar surplus charging benefits, so overall savings are typically lower.

Support is continually expanding. Tesla vehicles are a primary integration today, with more brands planned as APIs and partnerships allow. Check the dashboard or ask us during setup if your vehicle is already available.

Not always. OverflowEV can control charging through supported vehicle APIs and compatible charging methods. Dedicated smart charger integrations are on the roadmap. You can get started with what you have today and add hardware later as we expand support.

It depends on your inverter and monitoring equipment. Some systems report solar generation and home consumption directly. Others provide solar only, in those cases an additional energy monitor (or a supported third-party meter) is used so OverflowEV can calculate true surplus after home load.

Yes, in most cases. An external monitoring device can usually be added so home load is measured accurately. Once consumption and generation are both available, Free Solar charging works as designed. We’ll help you choose a supported option during onboarding.

Yes. OverflowEV uses secure encrypted cloud connections to talk to your vehicle and energy systems. There are no inbound firewall changes required on your home network, the platform is designed so your house doesn’t need to be exposed to the internet.

No. The software is designed to minimise unnecessary wake commands while still responding when charging should start, stop, or adjust. That keeps the car available when it matters without draining the 12V battery with constant polling.

These are the two automatic modes you’ll pick on the dashboard (and during setup). They both aim to put spare rooftop solar into the car first, they differ in how they work with grid top-ups and schedules.

Free Solar (solar-only) is for charging from excess solar. When surplus drops, clouds, appliances, or evening OverflowEV slows or pauses so you aren’t intentionally buying grid power for the EV as part of that mode. Choose Free Solar when your goal is maximum “free” kWh and you’re fine with charging stopping on dull or busy periods.

Solar+ still prioritises surplus solar during the day, and is the mode meant to work with off-peak / scheduled windows so the car can top up from the grid when you’ve planned it. Choose Solar+ when you want sunshine first and a reliable overnight or pre-departure fill without switching to Charge Now.

Quick pick: Free Solar = excess sunshine only. Solar+ = sunshine first, with schedules available to finish the job from the grid.

Related modes: Off pauses automatic charging; Charge Now charges immediately at the amps you set (uses grid if solar isn’t enough). To stop all solar/home/car polling while keeping your connection details, use Profile → Pause all integrations.

OverflowEV checks solar, home load, and the car on a short control cycle (typically about every 30 seconds), then sends a new charge rate if needed. Sunshine and household load can change faster than that, for example a cloud bank or a kettle/AC kicking in.

Until the next cycle runs and the car accepts a lower amp setting (or a pause), the charger may briefly keep drawing at the previous rate. That can show as a small amount of grid import even in Free Solar mode. It’s normal, usually short-lived, and the system is designed to pull the charge rate back down as soon as the next update applies.

Live dashboards often update more often than the control loop, so you may notice a dip or a thin import spike on the energy flow before the car’s amps catch up. Small overages like this don’t mean Free Solar is “using the grid on purpose”, they’re the lag between real-world changes and the next automatic adjustment.

Yes. Choose Charge Now whenever you need energy outside Free Solar / Solar+, for example before a longer trip or when solar isn’t available. You can return to Free Solar or Solar+ afterwards.

Yes. Smart scheduling is designed to pair with Solar+: surplus solar still comes first when it’s available, and your off-peak windows can top the car up from the grid when you’ve planned them. Prefer Free Solar when you want day-to-day charging tied to excess solar only, and use Charge Now (or switch to Solar+ with a schedule) when you need a planned grid fill.

The app will still work. OverflowEV charges when excess generation is available. If your home already uses most of the solar, surplus windows will be shorter and savings will depend on how much excess you actually have, Solar+ with schedules and monitoring still add value when you need a reliable top-up.