* feat(devices): add load-dependent DC-to-AC efficiency curve for GENETIC inverters
Real inverters are much less efficient at low load than at rated power
(e.g. 0.80 at 2 % vs. 0.93 at 7 % load). A constant dc_to_ac_efficiency
overrates night-time battery discharge into a small base load and, with
it, arbitrage and grid charging.
Add two optional inverter settings for the GENETIC optimizer:
- dc_to_ac_efficiency_curve: list of (load_fraction, efficiency) points,
load fraction = AC power / max_power_w. Points must be strictly
increasing in [0, 1] with efficiencies in (0, 1]; at least two points.
Linear interpolation, clamped at both ends. When set, the curve
replaces dc_to_ac_efficiency.
- dc_to_ac_efficiency_reference_load_fraction (default 0.06): load at
which the curve values stored energy without a specific conversion.
Battery discharges in Inverter.process_energy() use the efficiency at
the AC energy of each conversion. The end-of-horizon value, the terminal
and tail value curves and the AC charge break-even penalty use
Inverter.reference_dc_to_ac_efficiency.
Without a curve, dc_to_ac_efficiency_at() and the reference efficiency
return dc_to_ac_efficiency itself, so results are bit-identical to the
previous model. GENETIC0 is unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* fix(devices): evaluate the efficiency curve at the delivered AC load
When the battery limits a discharge (low state of charge or its power
limit), the conversion ran with the efficiency of the requested AC energy.
With a 1000 Wh battery at 10 % SoC, a 1000 W inverter and the curve
[(0, .8), (.5, .95), (1, .95)], a request of 500 Wh AC returned 95 Wh AC
from the available 100 Wh DC, although the curve gives 82.5 % at that load.
The delivered AC energy now solves a = dc * efficiency(a / rated) exactly on
the piecewise-linear curve (solve_ac_for_dc_energy), bounded by the request.
Unlimited discharges and inverters without a curve are unchanged.
Regression tests use a real Battery: low SoC and a power-limited discharge,
each with 60- and 15-minute slots, battery discharge losses, the load path
through process_energy, and constant efficiency.
* docs: regenerate OpenAPI for the efficiency-curve fix
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Co-authored-by: Christin <christin@BigBrother.bikini.bottom.zone>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Andreas <drbacke@gmx.de>
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