Catherine Sheridan spent many years working in Ervia, where she experienced the politics and the practicalities of building out and recasting critical Irish infrastructure such as gas and water networks. She is now chief operations officer with EI-H2, which is planning to build Ireland's first green hydrogen facility in Cork. For her Five Degrees of Change, Sheridan chose a national hydrogen strategy, decarbonising the gas grid, and takin a whole of energy system approach to climate action, as well as living a minimalist lifestyle, and taking an approach of imperfect pragmatism to her personal environmentalism.