An inside look at the world's largest solar-powered boat

Catamarans are fairly odd-looking boats, but earlier this week a special breed was docked at the North Cove Marina in Lower Manhattan. Alongside the typical handful of South Florida-based yachts that pop up here during the summer was an angular, flat-topped catamaran with a glistening blue deck called the MS Tûranor PlanetSolar. There's a reason why this boat stands out: last year it became the first ship to circumnavigate the globe on solar power alone. The 89,000 kg (nearly 100 ton) ship needs a massive solar array to capture enough energy to push itself through the ocean. An impressive 512 square meters (roughly 5,500 square feet) of photovoltaic cells, to be exact, charge the 8.5 tons of lithium-ion batteries that are stored in the ship's two hulls.

The Tûranor PlanetSolar (tûranor means "power of the sun" in Elvish) is taking a break in New York from its current mission: a science expedition from Miami to Norway led by a University of Geneva-based research team. The climatologists, biologists, and physicists aboard the PlanetSolar are taking measurements of the Gulf Stream to better understand the relationship between the ocean and the atmosphere in an effort to gain new insight about climate change. In particular, they're studying and measuring currents, airborne particles called aerosols that reflect infrared heat and solar radiation, and the myriad natural phenomena that allow the Gulf Stream to function. Since the PlanetSolar is seaworthy and is emission-free, it allows the team to ensure that measurements aren't skewed by exhaust.

During the New York stopover press was invited aboard the PlanetSolar for a view of this boat that functions without any carbon emissions. The vessel might not be the most practical — it's big, it's slow, and it needs to avoid clouds — but it's a bold demonstration of how renewable resources might power ships of the future.

Hint: Use the 's' and 'd' keys to navigate

• 
  The PlanetSolar docked in Lower Manhattan's North Cove Marina earlier this week. From left to right, it is surrounded by the New York Mercantile Exchange, Four World Financial Center, Three WFC, the Winter Garden Atrium, the recently topped-off One World Trade Center, and Two WFC.
• 
  The 35-meter long, 23-meter wide (about 115 by 75 feet) catamaran is completely powered by the photovoltaic cells that cover the boat's deck.
• 
  Tûranor means "powered by the sun" in Elvish.
• 
  All of the lithium-ion batteries (8.5 tons worth) and the two 60kW electric motors are located in the two partially-submerged hulls.
• 
  Crew members must go into the bottom of the boat and through these arms to access the batteries and engines, which are ensconced in a waterproof chamber.
• 
  The ship is designed to offer maximum surface area for the panels on the deck. The inhabitable space aboard the ship is quite limited, and there are few windows.
• 
  The angle of the rear flap can be adjusted using hydraulics to capture the most sunlight possible while at sea.
• 
  The photovoltaic cells on the deck are on tracks. When at sea, the crew manually extends the upper layer over the side of the ship, giving it a maximum of 516 square meters of panels.
• 
  The photovoltaic cells have a yield of 22.6 percent and cover nearly the entirety of the deck. Unlike some panels, they can support the weight of a human: up to 80kg per square meter.
• 
  Captain Gérard d'Aboville is piloting the SolarPlanet for its current voyage from Miami to Norway. Earlier in his life he solo-rowed across both the Atlantic and Pacific Oceans, journeys that took 71 and 134 days, respectively.
• 
  The bridge is fairly tight, with only space for a handful of people other than the captain. Most of what you see here is typical for a boat of this size, though there are a few special features.
• 
  Two 60kW electric motors, controlled here, power the PlanetSolar. Like an electric car, Captain d'Aboville says "it's very smooth because the boat moves without any noise, without any vibration."
• 
  This map offers a three-day prediction of cloud cover. Captain d'Aboville explains that when plotting trips "usually we take care of the sea, of the wind, and of the current. But [here] we have to take care of the Sun." He adds, "usually we don't go from A to B… we try to avoid the clouds."
• 
  The captain uses a more traditional map to plan PlanetSolar's upcoming trip to Boston. The ship has a max speed of 14 knots, but averages 5 knots — about a fast as a sail boat. The trip to Boston should take about two and a half days.
• 
  With 8.5 tons of lithium-ion batteries onboard, PlanetSolar is said to be "the largest civilian mobile battery" in the world. From empty it takes about two days to fully charge, and the batteries can drive the boat for 72 hours without any sunlight.
• 
  This panel controls PlanetSolar's exterior lighting. Captain d'Aboville says the ship "could have been built much lighter as a prototype… but the owner of the boat said that the boat after the world tour should have a second life" and built it to support up to 60 passengers when docked.
• 
  There's only space onboard for nine crew in six rooms.
• 
  A Manhattan-sized kitchen supports the crew. The ship took a total of 584 days to travel around the world.
• 
  PlanetSolar left Monaco on September 27th, 2010 and returned on May 4th, 2012 after circumnavigating the globe. It stopped over in 28 countries and 52 cities on the trip.