Ammonia as hydrogen carrier for realizing distributed on-site refueling stations implementing PEMFC technology

Abstract

Ammonia is a particularly promising hydrogen carrier due to its relatively low cost, high energy density, its liquid storage and to its production from renewable sources. Thus, in recent years, great attention is devoted to this fuel for realizing next generation refueling stations according to a carbon-free energy economy. In this paper a distributed onsite refueling station (200 kg/day of hydrogen filling 700-bar HFCEVs (Hybrid Fuel Cell Electric Vehicles) with about 5 kg of hydrogen in 5 min), based on ammonia feeding, is studied from the energy and economic point of views. The station is designed with a modular configuration consisting of more sections: i) the hydrogen production section, ii) the electric energy supplier section, iii) the compression and storage section and the refrigeration/dispenser section. The core of the station is the hydrogen production section that is based on an ammonia cracking reactor and its auxiliaries; the electric energy demand necessary for the station operation (i.e. the hydrogen compression and refrigeration) is satisfied by a PEMFC (Proton-Exchange Membrane Fuel Cell) power module. Energy performance, according to the hydrogen daily demand, has been evaluated and the estimation of the levelized cost of hydrogen (LCOH) has been carried out in order to establish the cost of the hydrogen at the pump that can assure the feasibility of this novel refueling station.

Design and Costs Analysis of Hydrogen Refuelling Stations Based on Different Hydrogen Sources and Plant Configurations

“…The proposed configurations were presented by the authors in previous papers [10,[21][22][23], in which the HRSs were sized for smaller hydrogen capacities (100 and 200 kg/day). In [10,21] in particular, ammonia-based HRSs with hydrogen capacities of 100 kg/day and 200 kg/day were proposed, respectively.…”

“…The proposed configurations were presented by the authors in previous papers [10,[21][22][23], in which the HRSs were sized for smaller hydrogen capacities (100 and 200 kg/day). In [10,21] in particular, ammonia-based HRSs with hydrogen capacities of 100 kg/day and 200 kg/day were proposed, respectively. In [10], the selected power production section was a SOFC unit, and in [21], a PEMFC system was implemented for satisfying the electricity requirements.…”

“…In [10,21] in particular, ammonia-based HRSs with hydrogen capacities of 100 kg/day and 200 kg/day were proposed, respectively. In [10], the selected power production section was a SOFC unit, and in [21], a PEMFC system was implemented for satisfying the electricity requirements. A biogas-based HRS, characterized by an autothermal reforming (ATR) unit, as the hydrogen production system, and sized for a capacity of 100 kg/day, was studied in [22].…”

“…The syngas (8) containing H 2 , CO, CO 2 , H 2 O, and N 2 , is cooled in the heat exchanger HE1 and then split into two streams: stream ( 12) is fed to the WGSR (water gas shift reactor) while stream (10) to the SOFC power unit. The air (21), feeding the cathodic compartment of the SOFC, is preheated in the HE2. Biogas, air, and water enter the ATR reactor after heating in the heat exchangers HE2, HE3, and HE1, respectively.…”

On-site solar powered refueling stations for green hydrogen production and distribution: performances and costs

“…The transition to a hydrogen-based mobility requires the development of an infrastructure that must be able to satisfy the hydrogen demand. Hydrogen refueling stations (HRSs) with on-site production from electric renewable energy sources (RES) are an interesting solution for assuring green hydrogen with zero CO2 emissions [1][2][3][4] The advantages achievable by adopting this solution are: i) increasing the share of electricity produced by renewable sources, ii) helping the integration of the fluctuating and non-programmable renewables (solar and wind) in the electric grid, iii) providing grid balancing services, iv) producing "green hydrogen" able to assure a sustainable mobility. The main issue of these on-site RES powered HRSs is the green hydrogen cost that is currently too high and depends on both the plant size (hydrogen production capacity) and on the hydrogen source [4].…”