Solis vs GivEnergy: which UK home battery for Octopus Agile?

GivEnergy exposes high-level "preset" endpoints: timed charge, timed discharge, timed export. Each preset takes a list of slots with start/end times in your site’s local clock. The cloud handles the firmware-level encoding for you, which makes integration straightforward — write a preset, get the same shape back when you read it.

Solis exposes lower-level command IDs (CIDs). Each slot is several CIDs you write together — time window, current limit, target SoC, enable bit. The cost of working at this level is that every write goes to a finite-life EEPROM on the inverter, so any well-behaved scheduler reads the current state before writing to avoid burning through the budget. The benefit is fine-grained control if you ever need it.

For a typical Agile household running one charge slot per night and one discharge slot in the evening, both work. The difference shows up if you want to layer in mid-day top-ups or ride multiple price dips: GivEnergy’s 10-slot Gen3 firmware gives more interleaving headroom; Solis’s slot 1 is the canonical write target with three more slots reserved if you need them.

GivEnergy uses a single API token you generate in the GivEnergy portal (Account Settings → Manage API Tokens). One paste and the connection works.

Solis uses an API key plus a separate secret, which is HMAC-signed on every request. The pair is requested through your installer for many UK accounts; some self-serve portals are starting to expose it directly. Two fields to paste rather than one, but the same overall ergonomics once you have them.

Both inverters interpret schedule slot times in the site’s local timezone, which sounds obvious until the clocks change in October or March. A scheduler that does not handle the IANA timezone correctly will silently shift every slot by an hour twice a year.

This is not a brand difference — both Solis and GivEnergy have the same trap, and both communities have a long history of "schedule went wrong after the clock change" reports. The thing to check is that whatever scheduler you use does the UTC↔local conversion in a DST-aware way.

GivEnergy has a dedicated "timed export" preset, which is convenient if you are on a dynamic export tariff (Octopus Outgoing Agile, etc.) and want to sell battery into the grid during high-price windows.

Solis treats export through the same discharge slots — the inverter discharges into the load first and exports any surplus. For most UK households on a flat export tariff, the practical outcome is identical; on dynamic export the GivEnergy split is slightly cleaner to model.

If you have not bought yet, the practical answer is: pick whichever your installer can deliver and service quickly. Both work well on Agile with a half-decent scheduler, and the savings ceiling is set by your tariff and load shape, not the brand.

If you already own one, do not switch. Run it on Agile, automate the daily plan, and pocket the difference. Brand-swapping a hybrid inverter is a four-figure decision that almost never pays back against the marginal scheduling difference.