# Lighting

![](/files/-MihpfEo2uc6eo-vb72O)

![](/files/-MihpeMf_53IYMlPzrME) - [\[source code\]](https://github.com/ladybug-tools/honeybee-grasshopper-energy/blob/master/honeybee_grasshopper_energy/src//HB%20Lighting.py)

Create a Lighting object that can be used to create a ProgramType or be assigned directly to a Room.

## Inputs

* **name**

  Text to set the name for the Lighting and to be incorporated into a unique Lighting identifier. If None, a unique name will be generated. 
* **watts\_per\_area \[Required]**

  A numerical value for the lighting power density in Watts per square meter of floor area. 
* **schedule \[Required]**

  A fractional for the use of lights over the course of the year. The fractional values will get multiplied by the \_watts\_per\_area to yield a complete lighting profile. 
* **radiant\_fract**

  A number between 0 and 1 for the fraction of the total lighting load given off as long wave radiant heat. 
* **visible\_fract**

  A number between 0 and 1 for the fraction of the total lighting load given off as short wave visible light. 
* **return\_fract**

  A number between 0 and 1 for the fraction of the total lighting load that goes into the zone return air (into the zone outlet node). Default: 0.0 (representative of pendant lighting). 
* **baseline**

  An optional number for the baseline lighting power density in W/m2 of floor area. This baseline is useful to track how much better the installed lights are in comparison to a standard like ASHRAE 90.1. If set to None, it will default to 11.84029 W/m2, which is that ASHRAE 90.1-2004 baseline for an office. 

## Outputs

* **lighting**

  A Lighting object that can be used to create a ProgramType or be assigned directly to a Room. 


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.ladybug.tools/hb-energy-primer/components/3_loads/lighting.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.