G n-grams:
エネルギー	9514176
エネルギ	168834
WWW examples

Common enough to record.

@@ -7,0 +8,4 @@
+</r_ele>
+<r_ele>
+<reb>エネルギ</reb>
+<re_inf>&ik;</re_inf>

Many of those match with キロカロリー, but yes, there are plenty of pages & PDFs where エネルギー is down as the calorific value of food.

@@ -17,0 +17,7 @@
+<gloss>strength</gloss>
+<gloss>power</gloss>
+<gloss>stamina</gloss>
+<gloss>get-up-and-go</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>

i still don't think it's necessary.  エネルギー just means "energy", which is a perfectly adequate description on a food label in either language.  AFAIK, they are required to give units on food labels anyway, so there is always a "kcal" note right next to it.

http://ja.wikipedia.org/wiki/カロリ�%
83%BC#.E6.A0.84.E9.A4.8A.E5.AD.A6.E3.81.AB.E3.81.8A.E3.81.91
.E3.82.8B.E3.80.8C.E3.82.AB.E3.83.AD.E3.83.AA.E3.83.BC.E3.80
.8D

Google comes up with 21 million hits for "エネルギー * kcal"
https://encrypted.google.com/search?
num=20&hl=en&safe=off&q=%22%E3%82%A8%E3%83%8D%E3%83%AB%E3%82
%AE%E3%83%BC+*+kcal%22&oq=%22%E3%82%A8%E3%83%8D%E3%83%AB%E3%
82%AE%E3%83%BC+*+kcal%22&aq=f&aqi=&aql=&gs_sm=3&gs_upl=8434l
9443l0l9619l2l2l0l0l0l0l70l137l2l2l0

I mean as it appears on "nutrition facts" on products, in 
place of "Calories." It does appear as "Energy" sometimes in 
English too but in Japan, it's almost always エネルギー.

新和英中辞典

No 国語 or JE refs support the "calories" gloss, except in the broadest way. The 中辞典 has a second sense of "〈気力･活力･精力〉 energy; strength; power; stamina; get-up-and-go", which is perhaps what you are referring to (?). Can you quote some references for your second sense?

Previous entry was rejected because it made the entry seem as 
if it only meant calories, which I can agree with. The calorie 
meaning is extremely common though, much more than カロリー, so 
I think that meaning deserves special mention.

@@ -15,0 +15,5 @@
+<sense>
+<pos>&n;</pos>
+<gloss>food energy</gloss>
+<gloss>calories</gloss>
+</sense>