Energy storage (Power to Gas) and carbon capture integration in chemical industry with hydrogen production

      In this project, we proposed for the first time the hybridization of Power to Gas with an electrochemical industry. This type of integration implements methanation in chemical plants whose lines of production are based on chemical electrolysis. Whenever a chemical electrolytic process generates hydrogen as by-product, it can be integrated in a Power to Gas process. At the same time, the carbon dioxide emissions from the electrochemical plant can be used in the methanation process.

      The main goal of the project was to study the application of this concept at ERCROS S.A. facilities. This chemical company has significant amounts of byproduct hydrogen coming from two electrolytic production lines: (i) sodium chlorate (NaClO3), and (ii) chlorine (Cl2) and potassium hydroxide (KOH). Both sources of byproduct hydrogen are purified and mixed for further use. The 50% of the hydrogen is diverted to ammonia production, the 25% to hydrochloric acid, and the 20% to hydrogen peroxide; the remaining 5% are losses. The application of Power to Gas consists of replacing ammonia production with synthetic natural gas production, since the latter is a more profitable product. In addition, the methanation process allows consuming CO2 emissions from the boilers installed in the plant.

  • It was found that the PtG-Electrochemical integration is economically feasible, according to the analysis performed under real operating data of ERCROS S.A.

  • Analyzing the base case scenario (5% discount rate) it can be observed that capital investment would be recovered in 8 years, generating a 4.8 M€ NPV at the end of the project lifetime with an IRR of 9%.

  • The technical analysis showed that the plant can operate 6000 hours per year, consuming more than the 85% of available hydrogen and 60% of the CO2 emitted by the chemical industry.

  • The hybrid plant can achieve a production of 518.5 m3/h (NTP) of synthetic methane and additionally 238 kg/h of medium-pressure steam that can be used in the industry.
Completed 100%

Project info

10 November 2015 – 30 October 2016

Total budget: 109,600 €

Principal investigator
Luis M. Romeo (
University of Zaragoza

[1] Power to gas-electrochemical industry hybrid systems: A case study. M Bailera, S Espatolero, P Lisbona, LM Romeo. Applied Energy, Volume 202, 15 September 2017, Pages 435-446.

This project received funding from Department of Industry and Innovation of the Government of Aragon, through the funding programme “Ayudas Innovaragón 2014” (Ref. INNOVA-A1-038-15).