This paper evaluates the potential of grid services in France, Italy, Norway and Spain to provide an alternative income for electrolysers producing hydrogen from wind power. Grid services are simulated with each country's data for 2017 for energy prices, grid services and wind power profiles from relevant wind parks. A novel metric is presented, the value of curtailed hydrogen, which is independent from several highly uncertain parameters such as electrolyser cost or hydrogen market price. Results indicate that grid services can monetise the unused spare capacity of electrolyser plants, improving their economy in the critical deployment phase. For most countries, up-regulation yields a value of curtailed hydrogen above 6 €/kg, over 3 times higher than the EU's 2030 price target (without incentives). However, countries with large hydro power resources such as Norway yield far lower results, below 2 €/kg. The value of curtailed hydrogen also decreases with hydrogen production, corresponding to the cases of symmetric and down-regulation.This publication has received funding from the Fuel Cells and Hydrogen 2 Joint Undertaking (now Clean Hydrogen Partnership) under the European Union's Horizon 2020 research and
innovation programme under grant agreement No. 779469. Any contents herein reflect solely the authors' view. The FCH 2JU and the European Commission are not responsible for any
use that may be made of the information herein contained. TECNALIA is a “CERVERA Technology Centre of Excellence” recognised by the Spanish Ministry of Science and Innovation. The authors wish to thanks Stefano Rossi of ARERA for his advices on the Italian energy market and regulation aspects
