Power Conversion Module

This item gives you two abilities when you're in Space Combat:

Power to Shields ( http://www.torhead.com/ability/aXCgkLV ) - Shield Regeneration is boosted significantly, but blast cannons deal very little damage.
Power to Blasters ( http://www.torhead.com/ability/6cLM5GR ) - Blast cannons deal more damage, but shield regeneration rate is cut in half.

This basically gives you an Offensive and Defensive mode in addition to the normal balanced mode (if you have both abilities off). Early on before you improve your shield with ship upgrades the Power to Blasters ability seems much more useful. Power to Shields significantly weakens the blast cannons and it's hard to kill anything at all.

Default hotkeys:

1 for Power to Blasters
2 for Power to Shields

To go back to normal mode, just toggle your current mode again.

General strategy: At start of mission, go to Power to Blasters. Once you take damage and there are no enemies present, go to Power to Shields. Switch back once either enemy is present again or shields are full.

It takes about 1.5 to 2 seconds to switch modes so some times it's better to just stay in Power to Blasters.

By far, the best ship upgrade you can get. I highly recommend buying this from the fleet at level 25. Essentially doubles your damage and shield regen, if you know how use it correctly. Just remember to stop firing your lasers while charging shields.

Costs 30 Fleet comms.