Each teaspoon of ejaculate has about 5 - 7 calories and some 200 - 500 million sperm. Since sperm make up only about 1 percent of semen, what accounts for the other 99 percent? Well, its other ingredients include:

Fructose sugar
Water
Ascorbic acid (a.k.a., vitamin C)
Citric acid
Enzymes
Protein
Phosphate and bicarbonate buffers (bases)
Zinc

tātad, aptuveni rēķinot -
1l spermas = 1000ml /5ml * 6cal = 1200 kalorijas