Open Access activists in research institutions have built several consortial organizations and this SHERPA site is an excellent place to begin becoming familiar with their work.
From the SHERPA "About" page:
"The original SHERPA partnership was formed for the SHERPA project (2002-2006) and drew from research-led universities with an active interest in establishing an example of a then-new concept - an open access institutional repository. After a year, the original 7 development partners were joined by 6 more partners to form a partnership of 21 individual institutions. We now have 26 institutions overall, consisting of 24 HE institutions, the British Library and the AHDS."
SHERPA: Securing a Hybrid Environment for Research Preservation and Access