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HOMER Pro 3.9


When adding a Generator, Boiler, or Reformer component, you must select a fuel. For the generic built-in components, the default fuel is diesel. You can leave diesel as the fuel or change to a different fuel in the library. Several common fuels are already in the library. You can also define your own custom fuel.

When you add a generator, boiler, or reformer, HOMER adds the corresponding fuel to your model by making a copy of the fuel from the library. You can add, remove, or modify fuels on the Fuels page under the Resources tab. You can also access the Fuels Resource page from the Generator, Reformer, or Boiler Component pages, by clicking the Manage Fuels button that appears next to the fuel selection drop-down menu (shown below).


On the Fuels Resource page, you can change the properties of the fuel, as described in the table below. You can add any fuel from your library into the model by selecting it from the drop-down menu and clicking the Add button. Changes to the fuel properties in this menu do not affect the fuel properties in the library. If you change the fuel properties and want to save the modified fuel in your user library, click the Copy to Library button.





A unique name for the fuel

Lower Heating Value

The energy released per kg of fuel combusted


Density in kg/m3 (the density of water is 1000 kg/m3)

Carbon Content

The mass-based carbon content of the fuel, in %

Sulfur Content

The mass-based sulfur content of the fuel, in %


The preferred units for the amount and price of the fuel. Liters, kg, and cubic meters are supported.

Fuel Type: Conventional

Typical fuels that are purchased at the specified price per unit from an external source (i.e., Diesel, Gasoline, etc.).

Fuel Type: Uses biomass resource

If this box is checked, this fuel can only be produced by the Biomass Resource.

Fuel Type: Stored Hydrogen

If this box is checked, the fuel can only be produced by the Electrolyzer or Reformer Components, and it cannot be purchased. The fuel can only be used by components that can connect to the hydrogen bus.

Limit Quantity

Components using this fuel do not operate after the total system consumption exceeds the value set in Quantity Available. This input is ignored if Bio Fuel or Stored Hydrogen is selected. Fuels with limited quantity cannot be used in Boiler or Reformer Components.

Quantity Available

The maximum quantity of fuel the system can use per year. This input is only used if "Limit quantity" is selected. This input is ignored if the fuel is not an "Conventional" type fuel. "Limit quantity" can only be used in the generator.

Fuel Price

Default price for this fuel. After the fuel is added to a model, the fuel price or sensitivity values can be chosen for the scenario in the model.

You can remove the fuel from the model by clicking the grey "x" in the corresponding row of the table of fuels available in the model. If you try to remove a fuel that is being used by any components in the model, you see an error message telling you which components are using the fuel. To remove the fuel, you first need to change the components' fuels so that none of them are using the fuel you want to remove.

See also

Create a New Fuel