I have recently started a contract with Eneco for my heating. I'm in Utrecht. I only use one radiator at my living room and I set the radiator valve to 4 after only 20 minutes it consumed almost 0.005 GJ.
|Per Hour||0,015 GJ|
|Per 12 hours a day||0,18 GJ|
|Per 30 days a mounth||5,4 GJ|
|Price by 28,47 Euros||153, 738 Euros|
To be honest I don't if this value is good or terrible but It seems it consumes alot.