A PGO is a Personal Health Environment.
With a PGO you can collect and view your own medical data from multiple healthcare providers in one place.
So you can link multiple patient portals to the PGO you use.

In a patient portal you can see the information that your healthcare provider has about you. This way you only see the data that the hospital has about you in your hospital's portal. And in your GP's portal only the data known to your GP.

You can view your medical data in both a patient portal and a PGO. But there is still a big difference between the two.
In a patient portal you can only view your medical data from the relevant healthcare organization.
With a PGO you can view all medical data from different healthcare organizations in one place.
You can therefore see a PGO as a patient portal, but with your medical data from all healthcare organizations that you have linked yourself.