Sorry, I posted the wrong amount. It is 25 Euros per day.
There is a gated car park under the hotel. It costs 15 Euros a day to park there.
One can park at the indoor parking below the hotel ( there is a daily charge) and in front of the hotel ( 1 hour free).
I sugget you to contact the hotel to be sure if it's free or not. When I've been there I didn't pay for it
Get an answer from Radisson Blu Palace Hotel, Noordwijk Aan Zee staff and past guests.