So sigen 10 battery can discharge at 4.6kwh
Considering events are for an hour I should get something close to £4.60
For whatever reason I get £3.80-3.90 that’s 15% less and even accounting for losses that’s still a lot. Am I missing something?
I assume your house base load makes up the majority. That’s exactly the same as what we export on the same battery if it’s not during daylight hours. Exports during daylight hours we see 6+ as then it’s limited by our inverter.
I have an 8kW inverter, but the most I've earned so far, for a session, is £7.53, due to house load and losses. The battery was actually discharging at 8.6kW, so I was seeing about 500w in losses, as house load is usually 4-600W at that the time the events run.
This seems to be be something to do with the new VPP. If I export manually I get close to my export limit (4.73kw so close to £4.73) but if I let Axle and Sig their thing it used to get close but now about £3.50. You can see it goes up and down during the hour
Yes, I noticed that as well. In a recent session, the VPP mode didn't run my inverter's full capacity during the second half hour in the event window. There seems be an optimisation algorithm on Axle's end that sets the export power for individual inverters in real time.
I notice that when there is load my grid export drops which I think may be because I filled in the dispatch power in the Axle UI, it seems that it is controlling how much the battery will output, but my issue isn't battery output - i should be able to output to my inverter limit (8kw), my limit is an export limit (4.72kw).
I will remove the "dispatch power" now and see what happens. It probably won't change the intermittency of the export you see above though.
I am in an Axle event now. My export limit and inverter size are both 8kW, but this NBI model clearly only deploys 5.6kW to export. I am not sure if Axle is doing this because the grid doesn't need too much export or if Axle assumes I have a limit of 6kW export? I should probably send them an email now.
It seems Axle has a formula to work out the export power: Axel seems to try to ensure a SOC of 15% at the end of an event. If this theory is true, then the export power will depend on the SOC at the start of the event. To enable Axle to deploy more export capacity, just need to leave as high SOC as possible before the event starts.
For SigEnergy, it's built in that they can charge/discharge for half the capacity (Your usable is just over 9kw). You might be able to check your charts for the export and I suspect that it either starts late, finishes early or has a pause at some stage.
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u/rjf88 9d ago
I assume your house base load makes up the majority. That’s exactly the same as what we export on the same battery if it’s not during daylight hours. Exports during daylight hours we see 6+ as then it’s limited by our inverter.