### Question
How is the "removable power source" defined?


### Answer
The term **removable power source** is defined in *49 U.S.C. § 47136* as follows -

> a power source that is separately installed in, and removable from, a zero-emission vehicle and may include a battery, a fuel cell, an ultra-capacitor, or other power source used in a zero-emission vehicle

#### Citation:
  - *49 U.S.C. § 47136*
  - Heading: **SUBTITLE VII-AVIATION PROGRAMS > PART B-AIRPORT DEVELOPMENT AND NOISE > CHAPTER 471-AIRPORT DEVELOPMENT > SUBCHAPTER I-AIRPORT IMPROVEMENT**

