A better idea is to give them double leave time, so you can get more and smarter people working in the project. The same people can choose between this project and working in a 4-day-work-week company, for more money.

But actually, a more efferent use of the resources would give the team a lot of auxiliary support, so they don't have to deal with the invoice system of the university and the providers, they don't have to care about how to install the heating/air conditioning, they have some money to hire a mechanical technician to help with the design of the system, and a lot of small things that waste a lot of time. (I work in a University and sometime I weep when I read http://www.joelonsoftware.com/articles/BionicOffice.html or http://www.joelonsoftware.com/articles/DevelopmentAbstractio... .)