Solar Time of Use optimisation

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t0ny

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#324845 2-Jun-2026 10:18

Hi, I have a Deye invertor and with contact energy on their 9PM-7AM half price plan. The installer has configured the invertor to top the battery to 50% after 9PM however, in the morning, I see it settled at 25% because other things such as the pool does it cycle as per graph during the night. ToU set as below:

Should i change the ToU table to efficiently use the tarrifs, battery etc.?

pih

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#3499505 2-Jun-2026 14:02

Yeah, if you want to use cheap overnight power for the pool then you should be doing that before the battery is set to charge up. In summer it would make sense to do the pool cycle during the middle of the day so that you're not drawing on the grid at all for it. If you can be even smarter (as in setting up smart automations), you should be able to configure the pool to do its thing during the day but only when you have excess solar production, and then do it at night with cheaper grid power if the daytime run was missed due to insufficient excess.

MikeAqua

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#3499519 2-Jun-2026 15:02

What's your pool doing at night? I always ran ours during the day, to reduce noise for the neighbours. In the new place it will run during the day to take advantage of solar.

Mike

Ge0rge

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#3499578 2-Jun-2026 18:41

ToU on the Deye can be a little non-intuiative. Your battery is set to charge from the grid to 50% after 2100. However, at 0100, it then stops charging from the grid, and is allowed to discharg back down to 25%.

If you want to make best use of your tarrif, I'd be making a couple of changes:

1. Change the finish time on the first ToU slot to 0700. The second should adjust automatically to match.

2. Change the percent of the first slot to at least 50%. Test and adjust this as you settle in to your system

3. Select grid charge for the first slot.

The above changes will mean that your battery charges to a minimum of 50% (or higher if you so select) over night, on your cheap power. When your tarrif changes, your system will then use battery from 0700, with the intent that you have enough charged capacity to cover the expensive part of the morning with battery, and then solar will kick in, cover the load and, if there is excess, charge the battery. Once the sun goes back down, you'll be on battery until 2100 again.

You'll need to test and adjust the percentages, I personally charge my battery to 90% on cheap power each night between 2300-0700.