Glossary¶
AC coupling¶
PV whose own inverters (micro-inverters or a string inverter) feed the house's AC wiring. Its forecast and its meter are in AC kW. Compare DC coupling.
BMS¶
The battery management system: the battery's own electronics. It protects the cells, and near full it slows charging, which is why a battery can count as full below 100 % (saturation).
DC bus¶
The DC side of a hybrid inverter, shared by whatever connects there: the battery, DC-coupled PV, a DC load.
DC coupling¶
PV strings wired to a hybrid inverter's DC bus, without inverters of their own. Its forecast is in DC kW.
Dead band¶
The gap between what PV diverted from charging the battery costs and what a kWh from the battery costs, made by the battery's losses and wear. See What a stored kWh is worth.
Dispatch as modelled¶
Whether the plant is running the dispatch its model describes. Defined in Inputs.
Folded and split¶
Two ways to describe a battery on a DC bus. Folded: one conversion from the AC side to stored energy, metered at the DC bus. Split: the battery's own step from the DC bus to stored energy, with the hybrid's conversion from the DC bus to AC separate. See Describe your plant.
Grid-charge window¶
Hours in which the plant tops the battery up from the grid toward a target, set in
plant/2. A top-up is that charge.
Heartbeat¶
A series whose samples show that readings were flowing: a meter that reports every few
seconds, or a client's own tick. Optional: without one, each series is trusted as far as
its known_until. Defined in Inputs.
Horizon¶
How far ahead a valuation reaches: 48 hours by default. See Slots and the horizon.
House load¶
What the plant's AC loads draw, as the plant meters it. Defined in Inputs.
Hybrid inverter¶
An inverter with a battery (and possibly PV strings and DC loads) on its own DC bus, converting between that bus and the AC side.
Issue¶
One forecast as published: its values over intervals, and when it was issued. A forecast input is the series of its issues, each at the time the client received it.
Make-up¶
How the battery replaces a kWh taken from it: by PV that would have spilled, by a grid
top-up, or by an import once it runs empty. A fill bounds a battery kWh's price; under
battery_value = "replacement" the make-up prices it. See The make-up
rule.
Marginal cost¶
What one more kWh used in a slot costs the site. See The marginal price.
MPPT¶
The maximum power point tracker: the part of an inverter that draws power from PV
strings. Its rating caps the strings' DC power (dc_rating_kw).
Provider¶
Where an input comes from: a tool's integration or any entity's attribute, named per
input in a sources/1 file. Forecasts can come from
either; measured values come from Home Assistant only, today, or from a dataset.
PV¶
Photovoltaic: solar panels.
Regime¶
What one more kWh in a slot would displace: export, curtailment, the battery, or an import. See Outputs.
Reserve¶
The SOC the plant keeps back (a backup reserve), reserve_soc. To the price rule, a
battery at its reserve is empty.
Pool¶
All the energy the battery holds, and what it cost, as one: its running average cost per stored kWh prices a kWh the battery delivers. See The battery's lots.
Saturation¶
The SOC at which charging counts as full, saturation_soc: below 1 where the
BMS slows charging near the top.
Slot¶
The unit of time the engine prices: 10 minutes by default.
SOC¶
State of charge: how full the battery is, as a fraction of its capacity (0.62, not 62 %) inside the library.
Stored cost¶
What the energy in the battery cost per stored kWh, its pool's running average: solar at the export it gave up, grid energy at the import it was bought at, energy of unknown cost as if bought at the import. See What a stored kWh is worth.
Surplus¶
PV the plant would export or curtail. See Outputs.
Telemetry path¶
Whatever carries a plant's readings to the client: a local connection, a cloud service, a recorder. When it goes quiet the readings stop, without the values changing.
Valuation¶
The engine's answer for one moment: every slot of the horizon, priced. A live value is one valuation run again from the meters for the slot from now.