# node-red-contrib-solar-power-forecast
A Node Red node to forecast the power output of a solar system under ideal conditions at a specified time.

Input message payload contains the timestamp for solar power output to be calculated at.

Uses the [suncalc](https://github.com/mourner/suncalc) to calculate the current sun position. Power forecast is adjusted for panel tilt, orientation, altitude, panel area, number of panels and panel efficiency.

## Configuration

- Lat & lon is the location of the solar system.
- Tilt is degrees from the horizontal.
- Orientation is the bearing in degrees from North. 
- Altitude is in metres above sea level.
- Area is the surface of a single panel in m^2.
- Number is the number of panels in the system.
- Efficiency is the conversion efficiency of the panel under ideal conditions.

## Input
- msg.payload contains the timestamp for the calculation.

## Output

msg.payload contains:
- timestamp: Timestamp of calculation
- powerforecast: Forecast of electrical power generated by the system under ideal conditions.

See [PV Education](http://www.pveducation.org/pvcdrom/properties-of-sunlight/solar-radiation-at-earths-surface) for details of calculation.