information for our energy future
information for our energy future
Megawatts is MW, not mW, which is the difference between one million watts (MW) and one-thousandth of a watt (mW).
Except for Celsius, units and their prefixes are not capitalised when shown in words. Most symbols are lower case except litre, which is shown as L, symbols for units named after people, such as W for watt, and the prefixes for mega and above (giga …). Additionally:
Source: Style manual for authors, editors and printers, Sixth edition 2002.
| Prefix | Symbol | Factor | Extended form |
|---|---|---|---|
| yotta | Y | 24 | 1,000,000,000,000,000,000,000,000 |
| zetta | Z | 21 | 1,000,000,000,000,000,000,000 |
| exa | E | 18 | 1,000,000,000,000,000,000 |
| peta | P | 15 | 1,000,000,000,000,000 |
| tera | T | 12 | 1,000,000,000,000 |
| giga | G | 9 | 1,000,000,000 |
| mega | M | 6 | 1,000,000 |
| kilo | k | 3 | 1,000 |
| hecto | h | 2 | 100 |
| deca | da | 1 | 10 |
| deci | d | -1 | 0.1 |
| centi | c | -2 | 0.01 |
| milli | m | -3 | 0.001 |
| micro | μ | -6 | 0.000 001 |
| nano | n | -9 | 0.000 000 001 |
| pico | p | -12 | 0.000 000 000 001 |
| femto | f | -15 | 0.000 000 000 000 001 |
| atto | a | -18 | 0.000 000 000 000 000 001 |
| zepto | z | -21 | 0.000 000 000 000 000 000 001 |
| yocto | y | -24 | 0.000 000 000 000 000 000 000 001 |