The Electric Jetpack is a variation of the Jetpack. As the name implies, the device runs on electricty, meaning you can fly without having to go through the trouble of making coalfuel cells or biofuel cells, instead using easier sources of power such as charcoal, solar or nuclear. However, there is a drawback. It is unable to fly above level 185, or 185 meters/blocks above bedrock. Note that it can only go to level 85 in the Nether. It requires 30,000 EU to fully charge, and runs for 3 minutes and 26 seconds, much longer than the regular fueled Jetpack, which runs for 63 seconds. It can be charged in ANY energy holder including a batbox, MFE, MFSU, solar panel, wind mill, or generator.
To activate an electronic jetpack, hold the space bar after equipping it in the chest armor slot. Hitting the "M" key while holding down the space bar switches the jetpack to "Hover Mode" Which allows for easier altitude changing.
Hover Mode currently only works singleplayer.
These are very useful in mines and quarries, but because of the height limit, it is not that useful for working on a house or ship. It takes longer to mine while flying, but the advantage is you can fly and get ores that are in the ceiling over lava. Contrary to popular belief, you do not bounce off the ceiling when you fly into it.
You can also use it as an elevator-like mechinism by making a shaft that leads to the surface and jumping down it into your mine. If you are planning to do this, it is recommended that you practice slowing yourself down. You can practice by putting 2 blocks of water at the bottom of a hill and jumping off of the top of the hill; as you descend, activate the jetpack so as to not hit the water. If you do not want to take the time to practice, it is recommended that you wear rubber boots.
Also note that while in hover mode, the player does not take fall damage, but instead uses a tiny amount of fuel to slowly descend.