Test chamber 8

Place portal in wall at end of short walkway.

Stand in front left corner of platform. Crouch if you feel safer. Place portal where energy ball bounces at end.

While energy ball is still traveling between the wall and the orange teleport, place blue teleport opposite energy ball reception bay.

Now that the lift is moving place blue portal above end of lift and wait for it to move under the portal. Then jump through and complete level.