The Ray Sphere was a device used by transferring the neuro-electric energy from a group of people to concentrate it into a human indevidual to unlock his/her powers. Though it will unlock the dormant abilities of the Conduit, it will kill the catalysts, and worse, cause a catastrophic explosion.
How many gallons of gas does the average mid-size car hold? The average fuel tank size for mid-size cars is 16 gallons. If the  price of gas was $3.59 per gallon, it would cost $57.44 to fill a  16 gallon tank.
So depending on the average fuel economy (MPG), a smaller car may have a 12 gallon tank, whereas a mid-size car is likely 16, and a larger SUV might be 20+. On average, I would say 16 gallons.