> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dalyenergy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Layout, Shading, and Losses

> Array geometry, near/far shading controls, and DC/AC loss assumptions

# Layout, Shading, and Losses

These sections define most physical and electrical assumptions per block.

## Layout Rules by `arrayType`

| `arrayType`          | Required fields                                   |
| -------------------- | ------------------------------------------------- |
| `fixed`              | `azimuth`, `axisTilt`, `tilt`                     |
| `tracker`            | `azimuth`, `axisTilt`, `backTracking`, `maxAngle` |
| `rotationalFloating` | `tilt`, `maxAngle`                                |

## Shading Rules

* `nearShading="octavia"` requires `shadingSceneId`.
* `nearShading="unlimited"` with `electricalImpact=true` requires `transverseDiodes`.
* If `electricalImpact=true` and `electricalImpactFraction` is omitted, it defaults to `1.0`.

## Losses Interpretation

All fractional losses are decimals (`0.02` means `2%`).

| Field                   | Meaning                                                  |
| ----------------------- | -------------------------------------------------------- |
| `moduleQuality`         | STC deviation from module nameplate (can be negative)    |
| `mismatch`              | Module/string mismatch loss                              |
| `dcohmic`               | DC wiring/conduction loss                                |
| `lid`                   | Light-induced degradation loss                           |
| `stringVoltageMismatch` | String voltage mismatch loss                             |
| `invAuxLoss`            | Include inverter auxiliary losses from inverter metadata |
| `uC`, `uV`              | Thermal coefficients for inverter temperature behavior   |

## AC System Inputs (per Block)

| Field                                | Meaning                                     |
| ------------------------------------ | ------------------------------------------- |
| `numberOfInverters`                  | Count of inverters represented by the block |
| `losses.acohmicLoss`                 | LV AC ohmic loss fraction                   |
| `losses.transformer.ironLoss`        | Constant transformer loss fraction          |
| `losses.transformer.copperLoss`      | Load-dependent transformer loss fraction    |
| `mvLosses.mvOhmicLossFraction`       | Optional MV ohmic loss fraction             |
| `mvLosses.mvTransformerLossFraction` | Optional MV transformer loss fraction       |

## Legacy PDF vs Current Constraints

| Topic                            | PDF v16 wording                      | Current validator behavior |
| -------------------------------- | ------------------------------------ | -------------------------- |
| `layout.gcr` range               | 0.1 to 0.85                          | 0.15 to 0.90               |
| `shading.transverseDiodes` range | Mode-specific wider values described | 0 to 10 enforced           |

<Warning>
  When PDF guidance conflicts with API validators, current API/model validators are authoritative.
</Warning>

## Schema-Assisted Tables

* `Layout` fields: `packages/docs/energy-models/_generated/layout.mdx`
* `Shading` fields: `packages/docs/energy-models/_generated/shading.mdx`
* `Losses` fields: `packages/docs/energy-models/_generated/losses.mdx`