Improved Battery Control: Nighttime Restriction for Car Charging

Dear GivEnergy community,

I hope this message finds you well. I wanted to reach out to discuss a potential enhancement to our GivEnergy battery control system, specifically related to managing battery output during nighttime car charging. I believe this could greatly benefit our overall energy efficiency and ensure we make the most of both our battery and grid resources.

Currently, some of us may have experienced instances where our batteries are drained during the night due to car charging, leaving us with insufficient power for more expensive daytime usage. To address this issue, I would like to propose the implementation of a scheduling timer and power output restriction feature that allows us to limit the battery output during specified nighttime hours.

By having the ability to restrict battery output during specific periods, such as during the night when car charging commonly occurs, we can ensure that enough power is reserved for our essential home consumption during the day. This means that any additional power required beyond what the battery can supply would be seamlessly sourced from the grid, preventing any disruption to our energy needs.

Allow me to provide an example to illustrate the potential benefits of this feature. Imagine having a nightly car charging routine that typically requires 7 kWh of electricity. Currently, if this charging process depletes the battery entirely, we might end up needing to purchase an extra few kWh from the grid during the day when energy prices are higher. However, with the proposed scheduling timer and power output restriction, we could allocate, for instance, only 1 kWh of battery output for home use and subsequent car charging during the night. This would ensure that the remaining 2 kWh output is kept and is available for later or at least until the sun comes up and normal daytime usage, and covering our average home consumption needs, Consequently, we would maximize the battery's efficiency and minimize our energy costs.

Now, I would like to open the discussion to our knowledgeable community. Does anyone currently have a solution or workaround for this particular issue that GivEnergy does not provide? Perhaps you have encountered a similar situation and found an effective way to manage night time car charging without draining the battery entirely?

Please feel free to share your thoughts, ideas, or any other suggestions you may have regarding this matter. Together, we can continue to improve our GivEnergy systems and promote sustainable energy consumption practices.

Thank you all for your time and contributions!

Warm regards,

Cosgrove

I am aware of three possible solutions:

1. Move the actual hardware wiring of your EV charger to before the inverter, hence it does not form part of your PV system at all, but draws directly from the grid. This is how mine was done and the issue is averted; or
2. Use the Remote Control page of the Portal, and use the PAUSE BATTERY settings to PAUSE DISCHARGE for the hours your intend to charge the car; or
3. Set the battery to Grid Charge for the time you charge the car, even a very low charge rate will stop if from discharging.

GaryS Thanks Option 1 & 2 would work if you could schedule those times and the functions for each setting, as opposed to being awake to manually change them. If this is already possible then it solves my problem.

Cosgrove You can set them from the REMOTE CONTROL page on the Portal. Open the My Inverts page, then click the cogwheel icon 2nd from the right on the inverter's line.

I need a combination of dynamic and scheduling, I need normal usage throughout the day but restricting power say from 2am through to 5am that way when there is a heavy pull of power in those times the battery will only deliver say 600w which is maximum normal home use. I might also want to charge the battery at night if the export is more cost effective that the import.

Cosgrove as above, timed charge for the GE battery is the easiest way. Set it for the entire off peak duration. Plus set the percentage you want the GE battery to be at at the end of the off peak rate.

Option 1 is a permanent change, a re-wire. It solves the problem as the GE inverter would not see the car charger being used, thus would not output its battery to the car charger.

If you want custom automation, Home Assistant (HA) is probably the best option. Have a look at the videos on YouTube by “speak to the geek”.

GivEnergy are working on alternative scheduling systems, but if you want something sooner, HA is the best option.

Zakalwe I’m learning and experimenting only just given birth to solar in this home, I will get there, I think Gary S has made me see the possibilities

Thanks to everyone for taking the time to respond and engage in a positive way. I think I get it.

Beware of Intelligent Octopus. You can end up with lots of half hour charge slots during the day. So setting your inverter(s) to charge during the off-peak period will not work. My workaround is to plug the car in just before the off peak window and set the departure time in the Octopus App to 05:30.

Slartibartfast Very true. ONly expection here is if you use an OHME charger on Intelligent, then the OHME charger is seen as the smart device by Octopus and not the car. Ohme has a toggle to restrict charging to your cheap hours, so the smart charge schedule that it creates, only falls within these hours. Octopus advises to turn this feature off, but you leave it on and not worry about day time charging. Slightly defies the purpose of Intelligent, but less eratic charging times.

Cosgrove if you have a myenergi Zappi2 EV charger then option 1 negates the ability to charge from excess solar, probably a diminishing return anyway due to 15p export rates with IO. The forthcoming Zappi/Octopus integration should help with battery draining. PredBat and HA also help, I would hope GE are learning loads from monitoring GivTcp and PredBat users.

Jase1703 does it?

Not sure of the exact models, but some zappis can still charge from export even if the GivEnergy is not seeing the zappi consumption.

If there's an export, zappi should notice it and if it's enough, start using it?

Depends exactly on how it's all wired I guess and where each of the CT clamps are.

Cosgrove Just set your inverter to do a timed charge with the same window as the car charger. The battery can't discharge to feed house or car while it is in timed charge mode. Use the Charge to % (Web Portal-Inverter Card-Settings-Timed Charge tab) to limit how much you put into the battery.

This works well, even if the target % is below the likely battery SOC. so you can stop the bettery charging altogether when charging the EV. (Useful for me as in the summer my SE facing roof makes overnight charging the home battery unnecessary.)

Thank you

Chris