# Usage time and forecasting horizon

It is important to clearly communicate when forecasts need to be made and to what horizon they will relate. TIM needs information on both aspects in order to build the most appropriate models. The user can communicate the time of forecasting using the Cron notation and the forecasting horizon using the relative time notation. By default, TIM will understand the forecasting horizon to consist of all samples between the time defined as ‘predictionFrom’ and the time defined as ‘predictionTo’.

## Examples¶

The following examples might clarify this topic.

### Example 1 – Electricity consumption¶

In this example, the data has a sampling rate of one hour. Every day at 08:20, a dispatcher wants to forecast the electricity consumption for the next day (i.e. for 24 hours from 00:00 to 23:00).

Usage | Prediction from | Prediction to |
---|---|---|

* 8 20 * | Day+1 | Day+1 |

### Example 2 – System imbalance¶

This exemplary dataset has a sampling rate of 15 minutes. Every hour from 05:50 to 15:50 a trader wants to forecast the system imbalance during the next 2 hours. This results in 8 forecasts, starting with 06:00.

Usage | Prediction from | Prediction to |
---|---|---|

* 5-15 50 * | QuarterHour+1 | QuarterHour+8 |

### Example 3 – Full scale forecasting¶

The data in this example has a sampling rate of one hour. Every hour from 06:00 to 16:00, the expected electricity load during the following 10 days needs to be predicted, future samples within the same day included.

Usage | Prediction from | Prediction to |
---|---|---|

* 6-16 0 * | Sample+1 | Day+10 |

### Example 4 – Solar production¶

This example deals with data with a sampling rate of 15 minutes. Every hour a forecast has to be made of the production of photovoltaic plant (a solar system; PV_prod) starting 3 hours ahead until the end of the day, two days ahead.

Usage | Prediction from | Prediction to |
---|---|---|

* * 0 * | Hour+3 | Day+2 |