All six tiers of energy capacitors can be crafted in an Enhanced Crafting Table.

An energy capacitor must be placed within 6 blocks of an Electric Machine, Energy Generator, Energy Regulator, or another capacitor (in a straight line, not diagonals).

They transfer energy between blocks in that range, so they can be used to extend your network. They will also store excess energy indefinitely, unless they are broken or the energy is used up.

A Capacitor's side texture will change depending on how much energy is stored in it, but you can more accurately measure it with a Multimeter.

Each tier of energy capacitor has a different capacity, listed below.