So you require a cert for personal projects. That doesn't mean a cert that chains to a public trust. You could easily cut your own cert and trust it on whatever device you wish to access the site on
And for e.g. intranet usage the organisation could set up their own internal CA to validate TLS certificates. The root certificate could be distributed in a manner suitable to the organisation. E.g. via Group Policy for Windows clients, or by simply including it in the disk image used for setting up new machines.