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The Vault - Fallout Wiki
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Fallout: New Vegas locations project
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Helios One
FNV Helios 1.png
Icon settlement large.png
Helios One loc.jpg
Map MarkerHELIOS One
FactionsUnited States Army (pre-War)
Poseidon Energy (pre-War)
Brotherhood of Steel (formerly)
New California Republic
LeadersBrig. Gen. Scott Lowe (pre-War)
Elder Elijah (formerly)
Lt. Haggerty
QuestsThat Lucky Old Sun
Sunshine Boogie
Classic Inspiration
ED-E My Love
I Could Make You Care
Restoring Hope
Cell NameHeliosOne
ref id000deb42
TerminalsHelios One terminals:
HELIOS One Mainframe Terminal
Gametitle-FNV.pngGametitle-FNV DM.png
Gametitle-FNV.pngGametitle-FNV DM.png

Helios One is a Poseidon Energy concentrated solar power plant that used to, and potentially still can, generate and provide power to the Las Vegas Strip and regional power grid. It also contains the control system for two experimental satellite weapon systems, the self defensive system Archimedes I and the offensive system Archimedes II.


Before the War

Established before the Great War as a next generation solar power plant, hailed as the Dawn of a Golden Age, Helios One was more than just a renewable source of energy. It doubled as a research and development facility for the U.S. Army's top secret orbital energy cannon, Archimedes II. Having joined the "Poseidon Family" when they began work, employees of Helios One were expected to keep company projects a secret; carelessly discussing developments could pose a threat to national security if the communists got wind of Poseidon projects.[1] The military side of affairs was handled by Brigadier General Scott Lowe, who oversaw the testing of the weapon on site.[2] Tests of the orbital weapon proved to be less than successful, as while both the orbital cannon (Archimedes II) and the array of smaller lasers dedicated to facility defense (Archimedes I) were successful, they resulted in a 2.5 minute downtime at the facility and system-frying power fluctuations in nearby installations, including Hidden Valley and Black Mountain. Further development was precluded by the destruction brought by the Great War.[3][4]

Operation Sunburst

After centuries of disuse, the Brotherhood of Steel discovered the facility. The occupation of Helios One was a decision made by Elder Elijah, who intended to unlock the secrets of the power plant. The Mojave chapter operated freely amid the Vegas wastes for several years, carrying out many reclamation missions without serious opposition.[5] In 2274, the NCR had officially set up a base at McCarran International Airport. From there, the NCR soon set its sights on the HELIOS One solar plant. Elijah, still believing that the plant contained an unprecedented military advantage, refused to leave the plant, and forced the Paladins to continue defending it. Two years of guerilla fighting against the NCR followed, culminating in Operation Sunburst in 2276.[5]

The NCR launched the operation to capture Helios One. Outnumbered by NCR soldiers, a pitched battle took place. Despite the Brotherhood being in control of far superior equipment, such as energy weapons and power armor, the Brotherhood had no reinforcements, and were gradually worn down by NCR's attacks. By the time the retreat signal was given by Paladin McNamara, more than half the chapter lay dead in the dust. The chapter's leader, Elder Elijah, disappeared without a trace. Brotherhood survivors retreated to Hidden Valley, while the NCR regrouped at the newly occupied Helios.[6] When they finally set out to locate and destroy remaining Brotherhood forces, they were nowhere to be found.[7]

Under NCR control

As NCR soldiers scouted the interior of the plant, they discovered that the Brotherhood had left them with one last nasty and spiteful goodbye in the solar collection tower before departing. The building's automated defense system had been activated, and the halls and corridors were now crawling with active and heavy armed security robots and turrets, meaning that the getting at the innards of the building was extremely dangerous.[8] Not being willing to divert manpower and resources towards such a hazardous undertaking and with no way of remotely shutting down the security system, the NCR command instead ordered the tower to be on lock-down, and had it secured in way that required permission from two separate security terminals before it could be entered.

The NCR established a firm foothold in Helios One and its vicinity, although due to a stroke of bad luck, an incompetent con artist was hired to act as the facility's principal engineer. He was unable to bring the facility to even moderate operational status, leaving it stuck at 1% efficiency. Ignacio Rivas was posted by the Followers of the Apocalypse to research the facility independently and ensure that the ignoramus hired by the NCR would not figure out a way to unlock the facility's dark secrets.


Main building

The facility is secured by an NCR detachment under the command of Lieutenant Haggerty. Due to the low power output, the facility is considered of low strategic value and suffers from a lack of manpower and supplies. The player has to gain the trust of the lieutenant or gain entry via a locked door on the eastern side of the building.

The interior of the building is dominated by long hallways and catwalks, still bearing the scars of the pitched battle that occurred there when the NCR stormed the facility. At the northern end of the facility lies a reinforced bunker where Fantastic tries to make the power plant work. His attempts are overseen by Ignacio Rivas. The bunker exits into the mirror yard.

Mirror yard

The yard is located immediately north of the main building, dominated by the solar collection tower. Computer-controlled solar arrays surround it and, in theory, track the sun, reflecting its rays at the collection tower. Unfortunately, due to the incompetence of Fantastic, they are stuck and barely work.

There are also two mirror control terminals set up in small shacks, and several tents erected by the NCR troopers guarding the facility. The western terminal is guarded by mines, bear traps, and a rigged shotgun, while the eastern terminal is guarded by attack dogs.

Solar collection tower

The solar collection tower is a complicated affair. When the Brotherhood retreated, they enabled the security systems. Military grade robots swarmed the corridors of the tower, including protectrons, Robobrains, Mister Gutsies, and/or sentry bots (dependent on the player's level).

Opposite the entrance is an unlocked door to a small room containing several frag mines (both active and inactive) and an easy turret control terminal. Downstairs is a small room with two pulse grenades on a shelf and an average safe containing pulse grenades, pulse mines, and assorted loot.

From the first area, the level continues through a double-wide door and down a sloping corridor guarded by a leveled security bot. The door at the bottom leads into another narrow corridor, which connects to a large vertical room, with several levels of catwalks, protected by a Gutsy.

The bottom of the catwalks exits into winding corridors branching left and right. The left corridor contains a single protectron locked in a shielded charging station, beyond which is a door secured with a laser tripwire (disarm with an 85 Repair or 67 Science skill). The room beyond contains four more protectrons locked in more shielded charging stations. Triggering the tripwire will activate and release the robots.

The door to the right in the initial corridor opens into a room contains some desks, skeletons and two Poseidon Energy ID cards. Both paths have doors that adjoin the final room, which contains the elevator going all the way up to the observation level.

Observation level

The observation level contains no hostiles. It does, however, hold the central mainframe used to control the plant. To activate the mainframe, see the article That Lucky Old Sun.

The door at the top level, beyond the war room table, leads to the observation deck.

Observation deck

Placed at the top of the tower, this circular deck forms a spiral, divided into two distinct levels. At the top is the reflector control panel, which activates the panel tracking sequence and completes That Lucky Old Sun.

The location can be technically fast traveled from, but this is not advised due to the likelihood of breaking scripted sequences.

Notable loot

Related quests


  • Activating the Archimedes I plant defense system kills all the NCR troops at the plant and will cause Caesar's Legion to occupy Helios One two days later, who will hold it until the end of the game. One of the Legion recruits will mention that in his opinion they don't even need the plant, they are just holding it to scare the NCR. They still keep Fantastic on hand though, suggesting they want to keep the station operational.
    • The ending slides reveal that under certain circumstances the Brotherhood of Steel or NCR will retake it after the events of the main game.
  • If the player sides with Father Elijah during Dead Money, a special cutscene is shown at the end explaining that Elijah makes wide spread use of holograms along with the lethal effects of the Cloud to kill all living things in the Mojave Wasteland before turning on the NCR, whilst also mentioning that Helios One is returned back to full operational capacity (and presumably Archimedes II as well).
  • Above the solar collection tower, a Mark II/IV/VI/VIII turret with a Stealth Boy cloak can be found. It won't attack the player and cannot be killed. This is what causes the red tick mark around the tower.
  • The hologram map in the Archimedes room is reused from Fallout 3's Raven Rock war room.
  • Any protectrons deactivated prior to setting off the laser tripwire, will reactivate and become immediately hostile. However, this does not prevent them from being deactivated a second time.

Behind the scenes

  • Helios was the Greek god of the sun and in Greek the same word still means "the sun".
  • This location was inspired by the The Solar Project located in the Mojave Desert.
  • Helios One's location script was written by Eric Fenstermaker.[9]
  • Kristen Altamirano handled lighting, prop placement, and final level polish for the location.[10]


  • PCIcon pc.png PlayStation 3Icon ps3.png Xbox 360Icon xbox360.png Sometimes when leaving the building via the back door, various non-player characters from nearby settlements, creatures or invisible objects will fall out of the air and will become hostile. These may include Rey, Audaz, Colmillo, Basura, Old Lady Gibson, No-bark Noonan, mole rats, radscorpions, barrels, a tin can or a combination of the above. Reloading the autosave made when you exited the door will correct this problem.
  • PCIcon pc.png Disarming the laser trip wire within the room with protectrons with a Science check does not prevent it from opening the forcefields and letting protectrons out to attack player.
  • PlayStation 3Icon ps3.png A hostile protectron may be found in one of their blue glowing holding containers, and if you kill him while he is still in it you may become trapped inside. The only way to fix this is by reloading your last save (possibly the autosave upon entering).


Helios One appears in Fallout: New Vegas and is mentioned in Dead Money.



  1. Helios One terminals; Terminal, "Can I Tell Him?"
  2. Helios One terminals; Terminal, Terminal 1, and Terminal 2, Upcoming Visit
  3. Helios One terminals; Terminal, ARCHIMEDES Testing
  4. Helios One terminals; Terminal, Results
  5. 5.0 5.1 Fallout: New Vegas Official Game Guide Collector's Edition p.43: "Brotherhood of Steel
    The Brotherhood of Steel is a militant organization devoted to the preservation of pre-war technology and human knowledge. Their professed mission is to preserve pre-war technology and human knowledge for the benefit of future generations. In practice, its definition of technology is strangely selective, ignoring basic but potentially useful technologies (genetic modification of crops and civil engineering, for example) in favor of combat technology such as energy weapons and power armor: and even now, nearly two centuries after the Great War, the Brotherhood zealously restricts the use and knowledge of such technologies to its own membership.
    The Mojave Brotherhood operated freely amid the Vegas wastes for several years, carrying out many reclamation missions without serious opposition. The balance of power shifted in 2251, when a large contingent of NCR troops entered the region and occupied Hoover Dam. Conflict was inevitable. Nearly two years of guerilla skirmishes culminated in a pitched battle at HELIOS One, a solar energy plant the Brotherhood had been refurbishing for several months with the goals of bringing it back online and activating its hidden offensive capabilities (the ARCHIMEDES II death ray). The battle for HELIOS One (Operation: Sunburst) proved a disaster for the Mojave Brotherhood. More than half its Paladins and Knights were killed. The chapter's leader, Elder Elijah, disappeared without a trace. The Brotherhood was driven from the facility, which suffered extensive damage. Survivors retreated to Hidden Valley.
    Since that defeat, the chapter's leader, Elder McNamara, has restricted activity outside the bunker to occasional reconnaissance missions and high-value raids. All operations take place at night, and engagement of NCR forces is strictly forbidden. Though the Brotherhood's ascetic lifestyle has prepared its members for a sequestered existence better than most, the passivity of their current situation has proved highly stressful."
    (Fallout: New Vegas Official Game Guide faction profiles)
  6. Fallout: New Vegas Official Game Guide Collector's Edition p.404-406: "[5.13] HELIOS One
    Constructed Pre-War by Poseidon Energy, HELIOS One is a concentrated solar energy plant consisting of an enormous array of reflectors and the power plant itself (housing steam turbines and all of the machines required to transform the energy into usable electricity). The plant has been damaged extensively since the war (including recent incursions between the NCR and the remaining Brotherhood of Steel forces in the Mojave). Now, only a third of its reflectors still fully intact and able to fully rotate. To make matters worse, various issues in the plant itself make the energy transfer inefficient, meaning the plant is operating far under potential. NCR doesn't posses the scientific knowledge to get the plant in ideal shape and both the Followers of the Apocalypse and Brotherhood of Steel are reluctant to help for political reasons. Due to its fragility, Caesar has no serious interest in HELIOS One, but his troops perform occasional raids on it to keep NCR's forces spread out."
    (Fallout: New Vegas Official Game Guide Collector's Edition Tour of the Mojave Wasteland)
  7. The Courier: "I thought the Brotherhood were all wiped out at HELIOS One. How could they have survived?"
    Cassandra Moore: "After the battle, we consolidated our hold on the plant before pursuing our enemies. It was a mistake, to be sure, but there wasn't really any place for them to go. When we finally gave chase, however, they had simply vanished. Some of our people think they had some means of conveyance, like the vertibirds the Enclave used, and hightailed it out of here. I think that they found someplace to hide close to HELIOS, and never went that far at all. Any other questions?"
    (Cassandra Moore's dialogue)
  8. The Courier: "Why would you trust me with this?"
    Ignacio Rivas: "I'm a man of letters. I'd be torn to pieces by the security system they have in that tower. I'd never reach the mainframe. But eventually the NCR will, or if not them, Caesar's Legion. They will use this place for war. Because the possibility exists you might do anything else, you're the only choice I have."
    (Ignacio Rivas' dialogue)
  10. Kristen Altamirano's website