Great write up of the basics, thanks for sharing!
Key decision factors for satellite operators when choosing between chemical and electric propulsion:
- Fuel Efficiency
- Lost Mission Revenue
- Responsiveness
- Thrust Requirements
- Deorbiting
- Upfront Cost
- Propellant Availability & Storage
- Fine Pointing Maneuvers
Summary
Electric propulsion is well suited for deep space and long-duration missions because it can generate power for a long time through solar arrays, from a very small amount of propellant.
But for missions where revenue, responsibility and responsiveness take high priority, chemical propulsion systems provide quick orbit insertion, responsible re-entry, and instantaneous thrust and is often the better choice.