# Consumption Details Figure 1 shows the additional parameters related to consumption. Initially, these values are taken from the vessel, but they can be modified or retrieved again from the vessel or the Tc In contract for each voyage.

Figure 1. Consumption Details

Values from this section will influence the voyage's consumption calculations but will not affect the vessel’s [speed and consumption](https://docs.dataloy.com/voyage-management-system/vessels/vessel-speed-and-consumption-data#boilers-per-day-and-generators-per-day). #### Generator and Boiler consumption source The dropdown field in the top right of the section allows you to track the currently selected consumption source. * Vessel - all generator and boiler consumption fields\* match the vessel’s generator and boiler consumption settings. * Tc In - all generator and boiler consumption fields\* match the TC In generator and boiler consumption settings. * Overridden - indicates that the voyage has uniquely defined generator and boiler consumption values.

Figure 2. Consumption source selector.

It is possible to update all generator and boiler consumption fields at once by selecting either the Vessel or TC In configuration. List of fields to be updated: * FO Port Idle * FO Port Working * MGO Port Idle * MGO Port Working * MGO At Sea * FO At Sea * FO Heating * FO Inerting * FO Cleaning * MGO Inerting {% hint style="info" icon="exclamation" %} Please review the detailed documentation of the Generator and Boiler consumption fields [here](https://docs.dataloy.com/voyage-management-system/vessels/vessel-speed-and-consumption-data#boilers-per-day-and-generators-per-day-overview) to understand how each field in this section affects the voyage consumption calculation. {% endhint %}