Between 1981 and 1985, Elio created and participated in the activities of the Institute for Energy Research and Design (IRPE SCRL), an institution among the forerunners of the application of the principles of sustainable development in the architecture of small and medium-scale systems urban planning and transport networks, as well as the potential for recovery and development of so-called Areas of Limited Resources.
In particular, he implemented a project of regional energy planning in Itri, southern Italy.
He was among the founders of the Centro Studi Formazione e Ricerca (Centre for Studies and Research Training) and a director from 1988 to 1991.
Mr Pacilio is a founding member of Verdi Ambiente e Società (Green Environment and Society), for which he served as vice president from 1991-2001, and a member of the National Council since 2001.
He co-founded the editorial Verde Ambiente (Green Environment), assuming the role of a board member from 1991 to 1998 and chairman of the board of directors since 1998.
In 1992, he designed and implemented the environmental education project Un Racconto per l’Ambiente (A Tale for the Environment), which evolved into the successful Green Cross Italia-organized Immagini per la terra, which is used to promote environmental conservation and protection in all Italian schools.