Solano became a member of the Executive Committee of the BOC Youth and initiated his journalistic career as a contributor to Adelante ("Forward"), a journal headed by Joaquín Maurín — a renowned Spanish communist who would go on to found the POUM with Andreu Nin.
After the eruption of the Spanish Civil War in 1936 Solano represented the JCI in the Executive Committee of the POUM and headed the weekly Juventud Comunista (Communist Youth).
Solano spent several months living in Paris and Chartres, and along with other poumistas attempted to reconstitute the Party, with an exile wing and one active inside Spain, and also maintain links with other organizations.
In 1941, after Nazi Germany conquered and occupied France, Solano was detained in Montauban and condemned to twenty years of forced labor by a Vichy regime tribunal.
In the 1980s, he was one of the founders of the Fundació Andreu Nin, which focused on the total rectification of the prestige of that communist politician and the clarification of the mystery of his death at the hands of the NKVD, and at the same time the defense of revolutionary Marxism and dialogue with all the tendencies of the socialist labor movement.
Solano is the author of a biography of Nin, a history of the JCI, and numerous essays on the POUM, the exile of Spanish revolutionaries in France, and the problems posed by the fall of the USSR and the collapse of Stalinism.
It was published jointly by Libros de la Catarata and the Fundació Andreu Nin, and is a personal and observed discussion of the poorly understood time period and political movement – some have called it one of the two most important works about the POUM, the other being Andrew Durgan's study of the Bloque Obrero y Campesino, BOC 1930-1936.