Is there ANY way to set up a timed export in advance?

What I want to do:

In these days of less PV generation we are filling up the batteries overnight at a rate of 12.5p.

Depending on solar during the day we have a bit of a surplus to export via Agile Outgoing at teatime (rates not brilliant at the moment but higher than 12.5p).

If I set this up in advance, the moment I enable timed export, Eco is disabled, the battery is frozen and any house load is drawn from the grid. Likewise, when the export time ends the battery is still frozen and the grid used.

So I have to be there to manually switch on and off the export.

There must be a better way than this. What is it!

GribinIsaf From the blurb on the inverter timed export page: "This mode will hold your battery power and discharge it at full power during a period you define". From your description, it is behaving as designed.

To commence a grid export at a specific time in the future, (from memory) others set an alarm on their phones to start and stop via the app. The only other way to do it would be using some home automation such as Home Assistant or Alexa if you use these.

If you are with Octopus on Agile, they have a way of controlling your imports or exports, either by price or time of day works great for me and sets my giv inverter back to eco when its finished.

Tim "This mode will hold your battery power and discharge it at full power during a period you define". From your description, it is behaving as designed.

Yes - the inverter is doing what it says it should do! I am just getting started with Home Assistant, so far it can read attributes from the inverter but not yet worked out how to instruct it. Any pointers welcome.

Hellipad If you are with Octopus on Agile, they have a way of controlling your imports or exports, either by price or time of day works great for me and sets my giv inverter back to eco when its finished.

Thanks, will look into that. The amount of time we want to export for each day varies according to the surplus we have.

GribinIsaf

GribinIsaf out of interest, after considering the conversion losses for the off-peak charging, how much are you hoping to make each year from the forced discharge? It's easy enough to script what you want, but is it worth the effort?

stevelewis out of interest, after considering the conversion losses for the off-peak charging, how much are you hoping to make each year from the forced discharge? It's easy enough to script what you want, but is it worth the effort?

I suppose I just enjoy experimenting with this sort of thing! At this time of year it is certainly worthwhile adding at least some charge to the batteries overnight - which is easy on the portal. (Our night rate is 12.5p 8pm to 7am). You are right, with current Agile Outgoing rates it is not actually worth very much exporting at tea time. I am just using at an exercise to acquire more skills in automation via HA, Node-RED etc.

BTW - what would you calculate the conversion losses as for import>battery>export?

GribinIsaf Assume 90% round trip efficiency. I'm on an old FIT scheme with deemed export, so my focus has been on maximising self-consumption by automating the overnight charge to reflect forecast generation and usage.

stevelewis Assume 90% round trip efficiency

Thanks

stevelewis Assume 90% round trip efficiency.

Why assume when the inverter measures it?

I've not had my system long, but so far it's 94.3%.

Portal - energy graph, change daily to total, change home to battery out, then battery in.
Efficiency = battery out / battery in * 100.

Rubikcube I've not had my system long, but so far it's 94.3%.

Here: 92% over five months

Rubikcube Why assume when the inverter measures it?

The values stored in the inverter are a good indicator but they aren't actual metered values. The metered values are the registers in the energy supplier's meter. My inverters have generated just over 9MWh since commissioning, according to the portal, whereas the "MCS" meter fitted as part of the installation says it's more like 8.6MWh. I can't say either is right. However, what I can say is that the inverters say that I have exported 3883kWh since installation whereas my smart meter says 4038kWh. These are large numbers but demonstrate that errors exist (about 4% for export). I can't even say that the energy supplier's smart meter is correct, but since that's what is used for my energy bill and SEG tariff, it's as right as it can be.

As far as making money from import -> battery charge -> export, if it makes sense at 90% round trip efficiency, anything better than 90% will make better sense. It would be a pity to make assumptions which you think are saving/making money only to find that the assumptions are incorrect.

Rubikcube because it's not a constant value, at least not for me... I checked mine before posting and it varies across the year, presumably due to losses varying with battery temp, charge/discharge rates, etc. 90% is an approximation.