Mr. Fusion Home Energy Reactor


What powers the modified DeLorean is a device called Mr. Fusion, which has the aesthetics and form factor of a household appliance. It is mounted to the back window of the DeLorean. At the beginning of the movie, Doc roots through a nearby garbage can to grab a banana peel and some beer. He rocks the top backwards on its hinge and dumps the items into its cylindrical reservoir, and closes it.

The device has the easy affordances of a consumer device. Doc flips it up, drops some beer and banana peels into a hollow, and snaps it shut. That’s it. There is no lock, no activation, no authorization. The device is hacked by Doc Brown, but you would expect anything outputting 1.21 Gigawatts to have some safety features in the off-the-shelf version.

Presuming it’s meant to power a house or even a car, I do wonder why it’s this size. You might want to have a bigger container to contain as much compost as possible to minimize the times it needs refilling. Of course we know this was a joke about the “Mr. Coffee” appliance available at the time, but if Tesla is eyeballing this as a model, it should take this into consideration.

Main Power Board


To restore the power that Nedry foolishly shut down (and thereby regain a technological advantage over the dinosaurs), Dr. Sattler must head into  the utility bunker that routes power to different parts of the park. Once she is there Hammond, back in the Visitors Center, communicates to her via two-way radio that operating it is a two part process: Manually providing a charge to the main panel, and then closing each of the breakers.

The Main Panel


To restore a charge to the main panel, she  manually cranks a paddle (like a kinetic-powered watch, radio, or flashlight), then firmly pushes a green button labeled “Push to Close”.  We hear a heavy click inside the panel as the switch flips something, and then the lights on the Breaker Panel list light up green.

Now that she has built up a charge in the circuit, she has to turn on each of the breakers one by one. Continue reading

Control Room Power Board


Once Dr. Sattler restores power to the park, Arnold needs to reboot the computer systems. To do this, he must switch off the circuits (C1–C3 in the screenshot above), and then switch off-and-on a circuit labeled “Main”.


It’s a good thing Arnold knows what he’s doing, since these switches are only labeled C1-3, and we don’t see any documentation in the camera frame.  As he turns off each circuit, different parts of the computer terminals in the Control Room shut down.  This implies that different computer banks are tied to the same power circuits as the systems they control.

So, since this is a major interface for the park, let’s make this bit explicit: When designing infrequently-used but mission-critical interfaces, take great care to explain use, using clear affordances and constraints so that mistakes are very, very difficult to make. 

It might look like a mistake to have all the little electrical labeling to the sides, since this cover would have to be removed to get the components where this information would be of use. But that’s perfect. A user needing to remove this panel must encounter this reference information to get to those components, and so would know where to find them. This is a brilliant example of the pattern Put the Signal in the Path. Let’s hope there are similar signs on other access panels.


Wait…where are the backups?

These are the central computer terminals that run Jurassic Park, and keep visitors safe from the “attractions.”  And there is no backup power.

When Arnold turns off the main circuit breaker, the computers (and servers behind them) turn off immediately.  The purpose and effect of the power switch deactivates all the systems in Jurassic Park, without any kind of warning or backup system.

For something as dangerous as deadly deadly dinosaurs—raised from the 65 million-year deep grave of extinction—the system deactivation should at least trigger some kind of warning.

Tornado sirens have backup batteries in case the city power goes out.  They are a solid example of a backup system that should exist, at minimum, to warn park-goers to move quickly towards shelter.  A better backup system would be a duplicate server system that automatically activates all the fences in the park.

Redundant Systems

When Arnold cycles the visitor center’s power system, it also trips the breakers for all of the other power systems in the park.  Primary safety systems like that should be on their own circuit.  It’s ok if the fridges turn off and melt the ice cream (though it may be an inconvenience), but that same event shouldn’t also deactivate the velociraptor pen security.  Especially when the ‘raptor pen is right next to the visitor center and is a known, aforementioned, deadly deadly threat.

Barbarella’s energy box


In addition to the portable brainwave detector, Dianthus also provides Barbarella with a number of weapons from the Museum of Conflict for her mission. All of these weapons are powered by a single energy box.

We only see it in use after she fires a single shot from the smallest of the weapons. She tries a second shot, but when it doesn’’t work, she glances at a device on the cuff of her boot. The device is designed in a taijitu, a yin-yang set of lights: one red, one white. They are blinking in an alternating pattern, and after viewing it she tells Pygar, ““My energy box is completely dead.””


Though having a visual signal is quite useful to understand the state of an invisible resource like power, the signal would be much more useful if it showed the amount of energy remaining, and gave warnings before the power was completely out. Failing all that, it would be more useful if she just put the device on the glove of her shooting hand so it was in her field of view at all times.

And though Barbarella’s culture doesn’t understand war, even a peaceful person can quickly come to realize the risk in making your available resources—like power for your weapons—wholly visible to your enemies.