{"id":"electricity-cost","engine":"core","category":"math","name":"Calculer le coût électrique","fields":[{"key":"watts","label":"Puissance (W)","type":"number","default":1500,"required":true,"min":0},{"key":"hours","label":"Heures (h/d)","type":"number","default":2,"required":true,"min":0,"max":24},{"key":"days","label":"Jours","type":"number","default":30,"required":true,"min":0},{"key":"rate","label":"Prix / kWh","type":"number","default":0.2,"required":true,"min":0}],"sample":{"watts":1500,"hours":2,"days":30,"rate":0.2}}