He was referring to "I am 185lbs. On Saturday I rode a moderate 65 mile loop at roughly 17 mph average", not to the OP. 65 miles at 17 mph is about 3.8 hours. 1400 cal over 3.8 hours is 368 cal/hr. If you assume 1 cal = 1kJ, divide by 3.6 and it gives you only 102W average. 2000 cal over 3.8 hours works out to 146W which is probably a little more realistic for a 185 pound rider going 17mph. Or, using BF's favorite calorie metric, 1400 cal would be 21.5 cal/mile and 2000 cal would be 30.8 cal/mile.

Now, as for the OP, 1500 cal for 25 miles is just crazy talk, by any metric.