The City Shield Generator is a defensive innovation created by the students and citizens of Ne'ushae and put into service in EE 001-v.
It should come as no surprise that when enemies enter into a planets atmosphere, the first things that are usually targetted as cities or military infrastructure. The Neshaten, due in large part to the perils of the Great War, had spent many years trying to rediscover some of their old ancient technology by prowling through ancient records.
The City Shield is one of those rediscoveries that was made. The shield functions by projecting a large dome over a city and also roughly ten miles away from the city to serve as a buffer zone.
Being a shield, its usage is to protect a city from all manners of threats, including weapons fire and solar disasters such as meteor impacts or solar flares and nuclear radiation. Because of this protection, the shielding is separated into segments that are each independently powered by a single large energy crystal although power can easily be diverted to another segment in the event of an emergency.
The shield was designed to be tough enough to withstand eight nuclear weapons all going off at the same time.
The city shield functions to protect the city from external forces, such as enemy weapons and solar events. It can expand to cover an entire city and roughly ten miles around that city, however, while the shield is active nothing can enter or leave without the shields frequency; this frequency allows friendly ships to match their shields frequency to that the city shield which they may then pass through.
In order for the shield to function, shield emitters must be placed at certain intervals around a city, these emitters may look rather inconspicuous as they do not require direct line of site of the sky to function, this means that they can be placed inside buildings or even under roadways or hidden in forests. Unfortunately, they can't be placed underground.
The C.S.G. requires four Lunabaren High-Energy Reactor 'per' emitter, this means that a city may have upwards of twenty or even thirty underground power plants that provide power just to the city shield alone. A series of capacitors can be installed to boost the power provided to these emitters in the event of a general power failure.
However, on planets that have a constantly active electrical storm - such as Nesha Prime - another source of limited power are lightning bolts. These bolts, because of the shear amount of power that a single bolt has, can be harnessed by attracting the bolts toward various grounding stations that then take the power of that bolt and stores it in capacitors. While this method can't be used to provide an indiffinent source of power to the city shield, it can be used to supplement it.
For all of the shields strengths, it also has a few weaknesses as well. The city shield requires a considerable amount of power, the likes of which can not be provided by low efficient systems such as hydro-electric and wind power, even though sources may commonly be found used by a city itself. The other drawback is that the emitters give off a characterized red glow that can give away the emitters position after long periods of operation.