Convert Terajoules to Kilocalories

Convert Terajoules (TJ) to Kilocalories (kcal) instantly and accurately.

Conversion Formula

kcal = TJ × 239005736.1

About Terajoules

A terajoule (TJ) is 10¹² J - the scale of nuclear yields in the kiloton range and large industrial accidents. One kiloton of TNT = 4.184 TJ; the Hiroshima bomb (15 kt) released ~62.8 TJ. The Halifax Explosion (1917) released ~3 TJ. A 500 MW coal plant consumes ~51.4 TJ/h of thermal input. Daily primary energy of Denmark is ~250-300 TJ; the UK ~3,800 TJ/day. A 1 GW nuclear reactor at 90% capacity factor generates ~77.7 TJ/day. 1 TJ = 10¹² J = 277,778 kWh = 277.78 MWh = 23.88 ktoe.

About Kilocalories

A kilocalorie (kcal) - the food Calorie (capital C) on US and Canadian nutrition labels - is exactly 4,184 J. WHO recommends ~2,000-2,500 kcal/day for adults. Energy density of nutrients: fat 9 kcal/g, carbohydrate 4 kcal/g, protein 4 kcal/g, ethanol 7 kcal/g. Running at 10 km/h burns ~600-800 kcal/h. Standard free energy of ATP hydrolysis is approximately −7.3 kcal/mol (−30.5 kJ/mol). Pre-SI thermodynamic tables in the US and Japan use kcal/mol for reaction enthalpies. 1 kcal = 4,184 J = 4.184 kJ = 3.968 BTU = 1.163 Wh.

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