Here is what I used for calculating ESR:
Here is a random datasheet which gives the ESR under certain conditions:
Suppose I want to calculate the ESR @ 100 kHz for the 220 µF capacitor:
I apply the following equation:
$$ \mathrm{ ESR = \frac{0.1}{2*PI*100^{3}*220*10^{-6}} } $$
Which is not equal at 0.18 Ohm which is given in the datasheet.
Where is my error?
We actually do not know at which frequency the dissipation factor is given, but I supposed that it is given for 100kHz.