This is true in a way, but only part of the picture. While virtually all the electricity that is produced in Norway does come from renewable sources, Norwegian energy producers sell a lot of their “guarantees of origin”[1] to energy companies in other European countries, who are then in turn allowed to market their energy as renewable. You can think of these as a kind of “virtual export”: Norway sells its energy to the rest of the continent and receives the “European Attribute Mix” in return. Since it would be pointless and inefficient to physically transfer this energy, virtual certificates are traded instead.
Because of this, the Norwegian Water Resources and Energy Directorate declares the energy consumed in Norway as being 58% fossil, 33% nuclear, and only 9% renewable[2], but Norwegian politicians and energy companies tend to forget this and prefer to emphasise the point that 98% of all energy produced in the country is renewable. Both claims are true, but somewhere someone is getting screwed over.
[1] https://en.wikipedia.org/wiki/Guarantee_of_origin [2] https://www.nve.no/energiforsyning/varedeklarasjon/nasjonal-... (in Norwegian)
However they are now built and there is still plenty of capacity so there have been no new major ones built for a long time.
There are some smaller privately owned ones being built but not on a big scale.
[1] https://en.wikipedia.org/wiki/Alta_Hydroelectric_Power_Stati...
[2] https://en.wikipedia.org/wiki/Environmental_impact_of_concre...
That's one of the great things about electric cars in Norway - you're actually going to get electricity from renewable sources.