After the boost module and crane, you'll go through an underwater section.
1. You'll have to attach the bottom of the boat to a base, and you can swim through it.
2. Swim down and to the right. A rope with lights will lead you to a pipe, go into it.
3. You'll enter an area with a light in the middle, and above this, is a crane on a track on the ceiling.
4. Pick up the object in the middle of the room. It's the same as the row of objects on the right that you passed.
5. We'll call it a battery. Put the battery on the far left where there's a holder for it.
6. Pick up a new battery on the right, and put it in the middle console.
7. Swim back to your ship, grab the garbage along the way.
8. Now that you know how to boost, perform a boost to charge the machine.
9. Once you boost, the city will be powered, unlocking the achievement.