The Nelly Sachs Prize (German:"Nelly Sachs Preis") is a literary prize given every two years by the German city of Dortmund. Named after the Jewish poet Nelly Sachs, the prize includes a cash award of €15,000. It honours authors for outstanding literary contributions to the promotion of understanding between peoples.
Every four years the German city of Dortmund gives out at least €30,000 in literary prize money
The context says every 2 years it gives out 15,000 euros, but it doesn't understand that means every 4 years it is 30,000 eurors