Restrict project list and access to projects in SOLAR_PROJECT_ADMIN
In transaction SOLAR_PROJECT_ADMIN the list of accessible projects should be reduced for a user.
Approach / Solution
You need to add a role (based on a SAP template or an individual one) with authorization object S_PROJECT to the user. For object field PROJECT_ID please enter the project name (column "Project" in SOLAR_PROJECT_ADMIN).
The following screen shows you a definition sample:
Note that you are NOT able to change the visibilty of projects in SOLAR_PROJECT_ADMIN! You can only restrict the access to the projects.