Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

Villagers hold torches during the Divina Pastora procession, as part of a festival to honour the Virgin of Los Rondeles, in the southern Spanish village of Casarabonela, near Malaga, late December 12, 2016. Villagers celebrate the festival on the eve of St. Lucia's Day and hold torches during the procession to represent light and vision. St. Lucia is the patron saint of vision. (Photo by Jon Nazca/Reuters)

“Falling Back To Earth” promises to be both spectacular and meditative, and presents a beautiful, thought-provoking vision of our relationship with the earth and with each other. (Photo by Dave Hunt/EPA)

Dutch actress, dancer and model Lotte Verbeek and the cast of “The Book Of Vision” recreate the pinnacle scene from the movie during the 77th Venice Film Festival at on September 03, 2020 in Venice, Italy. (Photo by Yara Nardi/Reuters)

Metallica and Lang Lang rehearse for THE 56TH ANNUAL GRAMMY AWARDS music industry's premier event takes place Sunday, Jan. 26 (8:00-11:30 PM, live ET/delayed PT) at STAPLES Center in Los Angeles on the CBS Television Network. Photo: Heather Wines/CBS ©2014 CBS Broadcasting, Inc. All Rights Reserved

The rear of the Chevorlet Chaparral 2X Vision Gran Turismo concept car at its world debut at the Los Angeles Auto Show in California, November 19, 2014. The annual event is open to the public beginning November 21. (Photo by Lucy Nicholson/Reuters)

German car manufacturer BMW presents the “Vision Next 100” concept car during the 100th anniversary celebrations in Munich, Germany, Monday, March 7, 2016. (Photo by Matthias Schrader/AP Photo)

A model wears an Apache costume in the kids carnival during The 13th Jember Fashion Carnival 2014 on August 21, 2014 in Jember, Indonesia. The 13th Jember Fashion Carnival (JFC) 2014 theme is “Triangle, Dynamic in Harmony” and consists of ten parades which include Mahabharata, Tambora, Phoenix, Pine Forest, Apache, Borobudur, Flying Kite, Wild Deers, Stalagmite, and Chemistry. This street carnival is claimed to be one of the biggest in the world and comprises more than 850 performers parading along 3.6 km road used as the catwalk. (Photo by Robertus Pudyanto/Getty Images)