The Component Fuel Cell
The Fuel Cell component models generation of electrical and thermal energy through the direct use of fuel.
Component Template
The component template Fuel_Cell.e-ctpl is located in the Component template library folder Renewable Energy Sources.
Integration Into a Scheme
How the Component Works
The Fuel Cell component represents the generation of electricity from fuel (hydrogen or methane from natural gas or biogas). This electrochemical process primarily generates electricity; as a side effect, heat is generated, which can be used.
The required fuel can be supplied from various sources; in particular, the Fuel Cell can be used in combination with a Power-to-Gas plant and a Fuel Storage system. Tutorial 26 demonstrates this constellation in its second variant.
For the input data, the information on energy converters in general applies. To optimize the size of the component, activate the structural optimization in the component ribbon.
Modeling With External Waste Heat
The external heat utilization of the fuel cell is optional in the TOP-Energy model. To activate it, place a check mark next to Modeling with external waste heat in the Technical input data.
Then the blue material model pins are shown in the scheme at the Fuel Cell component, to which you connect the Heat Demand.
Recovery of Fuel From the Exhaust Gas Stream
Not all of the fuel is always converted in the fuel cell. The unconverted fuel can be passed on to other components, e.g., a gas turbine. To further consider the unconverted fuel, activate the Further use of the exhaust gas flow with a check mark in the Technical input data form (see following figure).
Then the additional input parameter Fuel utilization is shown (see figure above), and a fuel exit pin appears on the Fuel Cell in the scheme (see following figure).
Fuel utilization is the proportion of fuel consumed to total fuel input, usually expressed as a percentage (%).
\( \begin{equation} \begin{aligned}fuel\ utilization= \frac{fuel_{consumption}}{fuel_{input}} \end{aligned}\end{equation}\).
A fuel cell with 100 kW nominal fuel power, 80 % fuel utilization, and 50 kW nominal electrical power outputs 50 kW of electrical power in nominal operation and provides 20 kW of energy for further use by other components.
Modeling With Extended Material Model Fuel (considering composition)
If you have selected Considering composition for the material model Fuel in the Simulation ribbon, use the Fuel Mixer component for mixing fuel flows and enter the Elementary composition in the Technical input data.
Select the Fuel cell type additionally if Considering composition is activated in the Simulation ribbon and the selection field Further use of exhaust gas flow is activated in the Technical input data of the Fuel Cell. You can select SOFC (solid oxide fuel cell) or PEFC (polymer electrolyte fuel cell).
The polymer electrolyte fuel cell can only utilize hydrogen, whereas the solid oxide fuel cell can utilize both hydrogen and methane. The conversion of the chemical energy of the continuously fed fuel and oxidant into electrical energy takes place at a temperature of 500 °C to 1000 °C. During the process, heat is released and water is produced. The heat can be used to reform methane into hydrogen, which is then used in the solid oxide fuel cell.
When modeling with the solid oxide fuel cell, another parameter field appears in the Technical input data: Efficiency of reforming.
The parameter Efficiency of reforming, given in %, is the proportion of reformed methane to the entering methane.
Economic Data
In addition to the operating costs and any reinvestment costs, the economic calculation takes into account the capital-related costs (investment costs) and the special costs and revenues of the fuel cell system.
The following table shows the investment costs, determined on the basis of data of the Publications Office of the European Union (Grosse, R., Christopher, B., Stefan, W., Geyer, R., Robbi, S., Long term (2050) projections of techno-economic performance of large-scale heating and cooling in the EU, EUR28859, Luxembourg 2017) and the Danish Energy Agency (Technology Data–Generation of Electricity and District Heating, 2022).
| Plant Size (kW) | Investment Costs of PEFC (EUR) | Investment Costs of SOFC (EUR) |
|---|---|---|
| 100 | 500.000 | 4.150.000 |
| 1.000 | 5.000.000 | 41.500.000 |
Balances of the CO2 Emissions and Primary Energy
The article How Life Cycle Assessment (LCA) Works describes how the savings of CO2 and primary energy are balanced. Use the examples for the use of a Power-to-Gas component as a guide.
