Convert kilowatt-hours to kilojoules (kWh to kJ)

One kilowatt-hour is exactly 3600 kilojoules, because an hour holds 3600 seconds and a kilojoule is a thousand watts for one second. Nothing is rounded on the way.

=

How to convert kilowatt-hours to kilojoules

Multiply the value in kilowatt-hours by 3600. The kilowatt-hour is the unit of the electricity meter, the kilojoule the unit of physics and of food labels: the same energy, counted by the supplier on one side and by the laboratory on the other.

kJ = kWh × 3600The other way round, divide by 3600.

Where these two units are used

The kilojoule is compulsory on European food labels, where the kilocalorie may appear beside it but never in its place.

Kilowatt-hours to kilojoules conversion table

0.1 kWh360 kJ
0.25 kWh900 kJ
0.5 kWh1,800 kJ
1 kWh3,600 kJ
2 kWh7,200 kJ
5 kWh18,000 kJ
10 kWh36,000 kJ
25 kWh90,000 kJ
50 kWh180,000 kJ
75 kWh270,000 kJ
100 kWh360,000 kJ
Show every value
  • 1 kWh = 3,600 kJ
  • 2 kWh = 7,200 kJ
  • 3 kWh = 10,800 kJ
  • 4 kWh = 14,400 kJ
  • 5 kWh = 18,000 kJ
  • 6 kWh = 21,600 kJ
  • 7 kWh = 25,200 kJ
  • 8 kWh = 28,800 kJ
  • 9 kWh = 32,400 kJ
  • 10 kWh = 36,000 kJ
  • 11 kWh = 39,600 kJ
  • 12 kWh = 43,200 kJ
  • 13 kWh = 46,800 kJ
  • 14 kWh = 50,400 kJ
  • 15 kWh = 54,000 kJ
  • 16 kWh = 57,600 kJ
  • 17 kWh = 61,200 kJ
  • 18 kWh = 64,800 kJ
  • 19 kWh = 68,400 kJ
  • 20 kWh = 72,000 kJ
  • 21 kWh = 75,600 kJ
  • 22 kWh = 79,200 kJ
  • 23 kWh = 82,800 kJ
  • 24 kWh = 86,400 kJ
  • 25 kWh = 90,000 kJ
  • 26 kWh = 93,600 kJ
  • 27 kWh = 97,200 kJ
  • 28 kWh = 100,800 kJ
  • 29 kWh = 104,400 kJ
  • 30 kWh = 108,000 kJ
  • 31 kWh = 111,600 kJ
  • 32 kWh = 115,200 kJ
  • 33 kWh = 118,800 kJ
  • 34 kWh = 122,400 kJ
  • 35 kWh = 126,000 kJ
  • 36 kWh = 129,600 kJ
  • 37 kWh = 133,200 kJ
  • 38 kWh = 136,800 kJ
  • 39 kWh = 140,400 kJ
  • 40 kWh = 144,000 kJ
  • 41 kWh = 147,600 kJ
  • 42 kWh = 151,200 kJ
  • 43 kWh = 154,800 kJ
  • 44 kWh = 158,400 kJ
  • 45 kWh = 162,000 kJ
  • 46 kWh = 165,600 kJ
  • 47 kWh = 169,200 kJ
  • 48 kWh = 172,800 kJ
  • 49 kWh = 176,400 kJ
  • 50 kWh = 180,000 kJ
  • 51 kWh = 183,600 kJ
  • 52 kWh = 187,200 kJ
  • 53 kWh = 190,800 kJ
  • 54 kWh = 194,400 kJ
  • 55 kWh = 198,000 kJ
  • 56 kWh = 201,600 kJ
  • 57 kWh = 205,200 kJ
  • 58 kWh = 208,800 kJ
  • 59 kWh = 212,400 kJ
  • 60 kWh = 216,000 kJ
  • 61 kWh = 219,600 kJ
  • 62 kWh = 223,200 kJ
  • 63 kWh = 226,800 kJ
  • 64 kWh = 230,400 kJ
  • 65 kWh = 234,000 kJ
  • 66 kWh = 237,600 kJ
  • 67 kWh = 241,200 kJ
  • 68 kWh = 244,800 kJ
  • 69 kWh = 248,400 kJ
  • 70 kWh = 252,000 kJ
  • 71 kWh = 255,600 kJ
  • 72 kWh = 259,200 kJ
  • 73 kWh = 262,800 kJ
  • 74 kWh = 266,400 kJ
  • 75 kWh = 270,000 kJ
  • 76 kWh = 273,600 kJ
  • 77 kWh = 277,200 kJ
  • 78 kWh = 280,800 kJ
  • 79 kWh = 284,400 kJ
  • 80 kWh = 288,000 kJ
  • 81 kWh = 291,600 kJ
  • 82 kWh = 295,200 kJ
  • 83 kWh = 298,800 kJ
  • 84 kWh = 302,400 kJ
  • 85 kWh = 306,000 kJ
  • 86 kWh = 309,600 kJ
  • 87 kWh = 313,200 kJ
  • 88 kWh = 316,800 kJ
  • 89 kWh = 320,400 kJ
  • 90 kWh = 324,000 kJ
  • 91 kWh = 327,600 kJ
  • 92 kWh = 331,200 kJ
  • 93 kWh = 334,800 kJ
  • 94 kWh = 338,400 kJ
  • 95 kWh = 342,000 kJ
  • 96 kWh = 345,600 kJ
  • 97 kWh = 349,200 kJ
  • 98 kWh = 352,800 kJ
  • 99 kWh = 356,400 kJ
  • 100 kWh = 360,000 kJ
  • 101 kWh = 363,600 kJ
  • 102 kWh = 367,200 kJ
  • 103 kWh = 370,800 kJ
  • 104 kWh = 374,400 kJ
  • 105 kWh = 378,000 kJ
  • 106 kWh = 381,600 kJ
  • 107 kWh = 385,200 kJ
  • 108 kWh = 388,800 kJ
  • 109 kWh = 392,400 kJ
  • 110 kWh = 396,000 kJ
  • 111 kWh = 399,600 kJ
  • 112 kWh = 403,200 kJ
  • 113 kWh = 406,800 kJ
  • 114 kWh = 410,400 kJ
  • 115 kWh = 414,000 kJ
  • 116 kWh = 417,600 kJ
  • 117 kWh = 421,200 kJ
  • 118 kWh = 424,800 kJ
  • 119 kWh = 428,400 kJ
  • 120 kWh = 432,000 kJ
  • 121 kWh = 435,600 kJ
  • 122 kWh = 439,200 kJ
  • 123 kWh = 442,800 kJ
  • 124 kWh = 446,400 kJ
  • 125 kWh = 450,000 kJ
  • 126 kWh = 453,600 kJ
  • 127 kWh = 457,200 kJ
  • 128 kWh = 460,800 kJ
  • 129 kWh = 464,400 kJ
  • 130 kWh = 468,000 kJ
  • 131 kWh = 471,600 kJ
  • 132 kWh = 475,200 kJ
  • 133 kWh = 478,800 kJ
  • 134 kWh = 482,400 kJ
  • 135 kWh = 486,000 kJ
  • 136 kWh = 489,600 kJ
  • 137 kWh = 493,200 kJ
  • 138 kWh = 496,800 kJ
  • 139 kWh = 500,400 kJ
  • 140 kWh = 504,000 kJ
  • 141 kWh = 507,600 kJ
  • 142 kWh = 511,200 kJ
  • 143 kWh = 514,800 kJ
  • 144 kWh = 518,400 kJ
  • 145 kWh = 522,000 kJ
  • 146 kWh = 525,600 kJ
  • 147 kWh = 529,200 kJ
  • 148 kWh = 532,800 kJ
  • 149 kWh = 536,400 kJ
  • 150 kWh = 540,000 kJ
  • 151 kWh = 543,600 kJ
  • 152 kWh = 547,200 kJ
  • 153 kWh = 550,800 kJ
  • 154 kWh = 554,400 kJ
  • 155 kWh = 558,000 kJ
  • 156 kWh = 561,600 kJ
  • 157 kWh = 565,200 kJ
  • 158 kWh = 568,800 kJ
  • 159 kWh = 572,400 kJ
  • 160 kWh = 576,000 kJ
  • 161 kWh = 579,600 kJ
  • 162 kWh = 583,200 kJ
  • 163 kWh = 586,800 kJ
  • 164 kWh = 590,400 kJ
  • 165 kWh = 594,000 kJ
  • 166 kWh = 597,600 kJ
  • 167 kWh = 601,200 kJ
  • 168 kWh = 604,800 kJ
  • 169 kWh = 608,400 kJ
  • 170 kWh = 612,000 kJ
  • 171 kWh = 615,600 kJ
  • 172 kWh = 619,200 kJ
  • 173 kWh = 622,800 kJ
  • 174 kWh = 626,400 kJ
  • 175 kWh = 630,000 kJ
  • 176 kWh = 633,600 kJ
  • 177 kWh = 637,200 kJ
  • 178 kWh = 640,800 kJ
  • 179 kWh = 644,400 kJ
  • 180 kWh = 648,000 kJ
  • 181 kWh = 651,600 kJ
  • 182 kWh = 655,200 kJ
  • 183 kWh = 658,800 kJ
  • 184 kWh = 662,400 kJ
  • 185 kWh = 666,000 kJ
  • 186 kWh = 669,600 kJ
  • 187 kWh = 673,200 kJ
  • 188 kWh = 676,800 kJ
  • 189 kWh = 680,400 kJ
  • 190 kWh = 684,000 kJ
  • 191 kWh = 687,600 kJ
  • 192 kWh = 691,200 kJ
  • 193 kWh = 694,800 kJ
  • 194 kWh = 698,400 kJ
  • 195 kWh = 702,000 kJ
  • 196 kWh = 705,600 kJ
  • 197 kWh = 709,200 kJ
  • 198 kWh = 712,800 kJ
  • 199 kWh = 716,400 kJ
  • 200 kWh = 720,000 kJ
  • 205 kWh = 738,000 kJ
  • 210 kWh = 756,000 kJ
  • 215 kWh = 774,000 kJ
  • 220 kWh = 792,000 kJ
  • 225 kWh = 810,000 kJ
  • 230 kWh = 828,000 kJ
  • 235 kWh = 846,000 kJ
  • 240 kWh = 864,000 kJ
  • 245 kWh = 882,000 kJ
  • 250 kWh = 900,000 kJ
  • 255 kWh = 918,000 kJ
  • 260 kWh = 936,000 kJ
  • 265 kWh = 954,000 kJ
  • 270 kWh = 972,000 kJ
  • 275 kWh = 990,000 kJ
  • 280 kWh = 1,008,000 kJ
  • 285 kWh = 1,026,000 kJ
  • 290 kWh = 1,044,000 kJ
  • 295 kWh = 1,062,000 kJ
  • 300 kWh = 1,080,000 kJ
  • 305 kWh = 1,098,000 kJ
  • 310 kWh = 1,116,000 kJ
  • 315 kWh = 1,134,000 kJ
  • 320 kWh = 1,152,000 kJ
  • 325 kWh = 1,170,000 kJ
  • 330 kWh = 1,188,000 kJ
  • 335 kWh = 1,206,000 kJ
  • 340 kWh = 1,224,000 kJ
  • 345 kWh = 1,242,000 kJ
  • 350 kWh = 1,260,000 kJ
  • 355 kWh = 1,278,000 kJ
  • 360 kWh = 1,296,000 kJ
  • 365 kWh = 1,314,000 kJ
  • 370 kWh = 1,332,000 kJ
  • 375 kWh = 1,350,000 kJ
  • 380 kWh = 1,368,000 kJ
  • 385 kWh = 1,386,000 kJ
  • 390 kWh = 1,404,000 kJ
  • 395 kWh = 1,422,000 kJ
  • 400 kWh = 1,440,000 kJ
  • 405 kWh = 1,458,000 kJ
  • 410 kWh = 1,476,000 kJ
  • 415 kWh = 1,494,000 kJ
  • 420 kWh = 1,512,000 kJ
  • 425 kWh = 1,530,000 kJ
  • 430 kWh = 1,548,000 kJ
  • 435 kWh = 1,566,000 kJ
  • 440 kWh = 1,584,000 kJ
  • 445 kWh = 1,602,000 kJ
  • 450 kWh = 1,620,000 kJ
  • 455 kWh = 1,638,000 kJ
  • 460 kWh = 1,656,000 kJ
  • 465 kWh = 1,674,000 kJ
  • 470 kWh = 1,692,000 kJ
  • 475 kWh = 1,710,000 kJ
  • 480 kWh = 1,728,000 kJ
  • 485 kWh = 1,746,000 kJ
  • 490 kWh = 1,764,000 kJ
  • 495 kWh = 1,782,000 kJ
  • 500 kWh = 1,800,000 kJ
  • 510 kWh = 1,836,000 kJ
  • 520 kWh = 1,872,000 kJ
  • 530 kWh = 1,908,000 kJ
  • 540 kWh = 1,944,000 kJ
  • 550 kWh = 1,980,000 kJ
  • 560 kWh = 2,016,000 kJ
  • 570 kWh = 2,052,000 kJ
  • 580 kWh = 2,088,000 kJ
  • 590 kWh = 2,124,000 kJ
  • 600 kWh = 2,160,000 kJ
  • 610 kWh = 2,196,000 kJ
  • 620 kWh = 2,232,000 kJ
  • 630 kWh = 2,268,000 kJ
  • 640 kWh = 2,304,000 kJ
  • 650 kWh = 2,340,000 kJ
  • 660 kWh = 2,376,000 kJ
  • 670 kWh = 2,412,000 kJ
  • 680 kWh = 2,448,000 kJ
  • 690 kWh = 2,484,000 kJ
  • 700 kWh = 2,520,000 kJ
  • 710 kWh = 2,556,000 kJ
  • 720 kWh = 2,592,000 kJ
  • 730 kWh = 2,628,000 kJ
  • 740 kWh = 2,664,000 kJ
  • 750 kWh = 2,700,000 kJ
  • 760 kWh = 2,736,000 kJ
  • 770 kWh = 2,772,000 kJ
  • 780 kWh = 2,808,000 kJ
  • 790 kWh = 2,844,000 kJ
  • 800 kWh = 2,880,000 kJ
  • 810 kWh = 2,916,000 kJ
  • 820 kWh = 2,952,000 kJ
  • 830 kWh = 2,988,000 kJ
  • 840 kWh = 3,024,000 kJ
  • 850 kWh = 3,060,000 kJ
  • 860 kWh = 3,096,000 kJ
  • 870 kWh = 3,132,000 kJ
  • 880 kWh = 3,168,000 kJ
  • 890 kWh = 3,204,000 kJ
  • 900 kWh = 3,240,000 kJ
  • 910 kWh = 3,276,000 kJ
  • 920 kWh = 3,312,000 kJ
  • 930 kWh = 3,348,000 kJ
  • 940 kWh = 3,384,000 kJ
  • 950 kWh = 3,420,000 kJ
  • 960 kWh = 3,456,000 kJ
  • 970 kWh = 3,492,000 kJ
  • 980 kWh = 3,528,000 kJ
  • 990 kWh = 3,564,000 kJ
  • 1,000 kWh = 3,600,000 kJ
  • 1,025 kWh = 3,690,000 kJ
  • 1,050 kWh = 3,780,000 kJ
  • 1,075 kWh = 3,870,000 kJ
  • 1,100 kWh = 3,960,000 kJ
  • 1,125 kWh = 4,050,000 kJ
  • 1,150 kWh = 4,140,000 kJ
  • 1,175 kWh = 4,230,000 kJ
  • 1,200 kWh = 4,320,000 kJ
  • 1,225 kWh = 4,410,000 kJ
  • 1,250 kWh = 4,500,000 kJ
  • 1,275 kWh = 4,590,000 kJ
  • 1,300 kWh = 4,680,000 kJ
  • 1,325 kWh = 4,770,000 kJ
  • 1,350 kWh = 4,860,000 kJ
  • 1,375 kWh = 4,950,000 kJ
  • 1,400 kWh = 5,040,000 kJ
  • 1,425 kWh = 5,130,000 kJ
  • 1,450 kWh = 5,220,000 kJ
  • 1,475 kWh = 5,310,000 kJ
  • 1,500 kWh = 5,400,000 kJ
  • 1,525 kWh = 5,490,000 kJ
  • 1,550 kWh = 5,580,000 kJ
  • 1,575 kWh = 5,670,000 kJ
  • 1,600 kWh = 5,760,000 kJ
  • 1,625 kWh = 5,850,000 kJ
  • 1,650 kWh = 5,940,000 kJ
  • 1,675 kWh = 6,030,000 kJ
  • 1,700 kWh = 6,120,000 kJ
  • 1,725 kWh = 6,210,000 kJ
  • 1,750 kWh = 6,300,000 kJ
  • 1,775 kWh = 6,390,000 kJ
  • 1,800 kWh = 6,480,000 kJ
  • 1,825 kWh = 6,570,000 kJ
  • 1,850 kWh = 6,660,000 kJ
  • 1,875 kWh = 6,750,000 kJ
  • 1,900 kWh = 6,840,000 kJ
  • 1,925 kWh = 6,930,000 kJ
  • 1,950 kWh = 7,020,000 kJ
  • 1,975 kWh = 7,110,000 kJ
  • 2,000 kWh = 7,200,000 kJ
  • 2,050 kWh = 7,380,000 kJ
  • 2,100 kWh = 7,560,000 kJ
  • 2,150 kWh = 7,740,000 kJ
  • 2,200 kWh = 7,920,000 kJ
  • 2,250 kWh = 8,100,000 kJ
  • 2,300 kWh = 8,280,000 kJ
  • 2,350 kWh = 8,460,000 kJ
  • 2,400 kWh = 8,640,000 kJ
  • 2,450 kWh = 8,820,000 kJ
  • 2,500 kWh = 9,000,000 kJ
  • 2,550 kWh = 9,180,000 kJ
  • 2,600 kWh = 9,360,000 kJ
  • 2,650 kWh = 9,540,000 kJ
  • 2,700 kWh = 9,720,000 kJ
  • 2,750 kWh = 9,900,000 kJ
  • 2,800 kWh = 10,080,000 kJ
  • 2,850 kWh = 10,260,000 kJ
  • 2,900 kWh = 10,440,000 kJ
  • 2,950 kWh = 10,620,000 kJ
  • 3,000 kWh = 10,800,000 kJ
  • 3,050 kWh = 10,980,000 kJ
  • 3,100 kWh = 11,160,000 kJ
  • 3,150 kWh = 11,340,000 kJ
  • 3,200 kWh = 11,520,000 kJ
  • 3,250 kWh = 11,700,000 kJ
  • 3,300 kWh = 11,880,000 kJ
  • 3,350 kWh = 12,060,000 kJ
  • 3,400 kWh = 12,240,000 kJ
  • 3,450 kWh = 12,420,000 kJ
  • 3,500 kWh = 12,600,000 kJ
  • 3,550 kWh = 12,780,000 kJ
  • 3,600 kWh = 12,960,000 kJ
  • 3,650 kWh = 13,140,000 kJ
  • 3,700 kWh = 13,320,000 kJ
  • 3,750 kWh = 13,500,000 kJ
  • 3,800 kWh = 13,680,000 kJ
  • 3,850 kWh = 13,860,000 kJ
  • 3,900 kWh = 14,040,000 kJ
  • 3,950 kWh = 14,220,000 kJ
  • 4,000 kWh = 14,400,000 kJ
  • 4,050 kWh = 14,580,000 kJ
  • 4,100 kWh = 14,760,000 kJ
  • 4,150 kWh = 14,940,000 kJ
  • 4,200 kWh = 15,120,000 kJ
  • 4,250 kWh = 15,300,000 kJ
  • 4,300 kWh = 15,480,000 kJ
  • 4,350 kWh = 15,660,000 kJ
  • 4,400 kWh = 15,840,000 kJ
  • 4,450 kWh = 16,020,000 kJ
  • 4,500 kWh = 16,200,000 kJ
  • 4,550 kWh = 16,380,000 kJ
  • 4,600 kWh = 16,560,000 kJ
  • 4,650 kWh = 16,740,000 kJ
  • 4,700 kWh = 16,920,000 kJ
  • 4,750 kWh = 17,100,000 kJ
  • 4,800 kWh = 17,280,000 kJ
  • 4,850 kWh = 17,460,000 kJ
  • 4,900 kWh = 17,640,000 kJ
  • 4,950 kWh = 17,820,000 kJ
  • 5,000 kWh = 18,000,000 kJ
  • 5,100 kWh = 18,360,000 kJ
  • 5,200 kWh = 18,720,000 kJ
  • 5,300 kWh = 19,080,000 kJ
  • 5,400 kWh = 19,440,000 kJ
  • 5,500 kWh = 19,800,000 kJ
  • 5,600 kWh = 20,160,000 kJ
  • 5,700 kWh = 20,520,000 kJ
  • 5,800 kWh = 20,880,000 kJ
  • 5,900 kWh = 21,240,000 kJ
  • 6,000 kWh = 21,600,000 kJ
  • 6,100 kWh = 21,960,000 kJ
  • 6,200 kWh = 22,320,000 kJ
  • 6,300 kWh = 22,680,000 kJ
  • 6,400 kWh = 23,040,000 kJ
  • 6,500 kWh = 23,400,000 kJ
  • 6,600 kWh = 23,760,000 kJ
  • 6,700 kWh = 24,120,000 kJ
  • 6,800 kWh = 24,480,000 kJ
  • 6,900 kWh = 24,840,000 kJ
  • 7,000 kWh = 25,200,000 kJ
  • 7,100 kWh = 25,560,000 kJ
  • 7,200 kWh = 25,920,000 kJ
  • 7,300 kWh = 26,280,000 kJ
  • 7,400 kWh = 26,640,000 kJ
  • 7,500 kWh = 27,000,000 kJ
  • 7,600 kWh = 27,360,000 kJ
  • 7,700 kWh = 27,720,000 kJ
  • 7,800 kWh = 28,080,000 kJ
  • 7,900 kWh = 28,440,000 kJ
  • 8,000 kWh = 28,800,000 kJ
  • 8,100 kWh = 29,160,000 kJ
  • 8,200 kWh = 29,520,000 kJ
  • 8,300 kWh = 29,880,000 kJ
  • 8,400 kWh = 30,240,000 kJ
  • 8,500 kWh = 30,600,000 kJ
  • 8,600 kWh = 30,960,000 kJ
  • 8,700 kWh = 31,320,000 kJ
  • 8,800 kWh = 31,680,000 kJ
  • 8,900 kWh = 32,040,000 kJ
  • 9,000 kWh = 32,400,000 kJ
  • 9,100 kWh = 32,760,000 kJ
  • 9,200 kWh = 33,120,000 kJ
  • 9,300 kWh = 33,480,000 kJ
  • 9,400 kWh = 33,840,000 kJ
  • 9,500 kWh = 34,200,000 kJ
  • 9,600 kWh = 34,560,000 kJ
  • 9,700 kWh = 34,920,000 kJ
  • 9,800 kWh = 35,280,000 kJ
  • 9,900 kWh = 35,640,000 kJ
  • 10,000 kWh = 36,000,000 kJ

An hour is 3600 seconds and a watt is one joule per second, so a kilowatt-hour is 3.6 megajoules by construction, an exact value rather than a measured one. The kilowatt-hour is not an SI unit, although the SI accepts the hour alongside its own. Methodology & sources.

Frequently asked questions

kWh or kW/h, which notation is right?

kWh, or kW·h with a middle dot. A slash means a division, so kW/h would read as kilowatts per hour, the rate at which a power changes, which has nothing to do with a quantity of energy. The kilowatt-hour is a product instead, a power multiplied by a duration. A 2 kW heater running for 90 minutes uses 3 kWh, that is 10,800 kJ. The SI would write the same energy as 3.6 megajoules, the hour not being its unit of time.

How many kilojoules does a kettle need?

Heating one and a half liters of water from 15 to 100 degrees takes 534 kilojoules, or 0.148 kilowatt-hour. The arithmetic is one line long: 4.186 kilojoules raise one kilogram of water by one degree, and there are 85 degrees to climb. A 2200 watt kettle takes a little over four minutes, the real time running about a tenth longer because the body and the surrounding air take their share.

Why does a gas bill turn cubic meters into kilowatt-hours?

Because the meter measures a volume while gas is sold as energy. The supplier multiplies the metered cubic meters by a conversion coefficient that depends on the composition of the gas delivered and on the altitude of the town: in France it runs from about 10.6 to 12.8 kilowatt-hours per cubic meter, that is 38,000 to 46,000 kilojoules. A cubic meter of natural gas therefore carries about ten times the energy of one kilowatt-hour of electricity, which is why the two bills never compare on the price of a kilowatt-hour alone.

How many kilojoules in a kilogram of TNT?

Exactly 4184 kilojoules, or 1.162 kilowatt-hour, because the ton of TNT is a conventional unit worth one billion thermochemical calories. One gram of TNT is therefore one kilocalorie exactly: the unit that sizes explosions is the unit printed on food labels. The convention is round, the substance less so, trinitrotoluene releasing close to 4600 kilojoules per kilogram in practice. A 2200 watt kettle reaches the same energy in thirty-two minutes.

A hundred kilowatt-hours as petrol or as battery, what changes?

Eleven liters on one side, more than half a tonne on the other. A liter of petrol carries about 32 megajoules, or 8.9 kilowatt-hours, so a hundred kilowatt-hours fit into eleven liters and twelve kilograms. The same energy stored in lithium cells needs a pack of five to six hundred kilograms, a battery topping out near 0.18 kilowatt-hour per kilogram where petrol offers 12.2. The mass ratio approaches seventy, but the useful gap is far smaller: a combustion engine turns only a quarter of the tank into motion, against close to nine tenths for an electric driveline.

Related conversions

kilojoules to kilowatt-hours (kJ to kWh) Energy kWh to kcal kWh to J kilocalories to kilojoules (kcal to kJ) kJ to kcal Kilowatt-hours to watt-hours Joules to kilowatt-hours Joules to kilojoules