Hyundai HDC-6 Neptune

The Hyundai HDC-6 Neptune is a hydrogen fuel-cell concept for a heavy-duty tractor-trailer, shown by Hyundai Motor Company at the North American Commercial Vehicle Show in Atlanta, Georgia.

Hyundai released the first renderings on 21 October 2019, and the truck itself was displayed at the show, which ran from 28 to 31 October 2019.

It was the company’s first hydrogen-only concept for commercial vehicles, and Hyundai said it was a first step toward exploring opportunities in the US commercial vehicle market. The name refers to the Roman god of the seas, symbolising hydrogen-powered natural elements of the sea, which Hyundai calls the largest potential source of hydrogen on Earth.

The design draws on the streamlined railway trains of the 1930s and their Art Deco style. The cab has a large panoramic windscreen, and a thin LED strip wraps around the front in place of conventional headlamps.

A ribbed lower section works as a grille and hides retractable steps, while a sliding door gives access to the cab. Cameras replace the mirrors and reportedly give the driver a 270-degree view to the sides and rear.

According to the renderings, the interior has swivel seats, digital displays, a loft-style sleeping area, a shower and a kitchen. Luc Donckerwolke, Hyundai Motor Group’s chief design officer, said that the fuel cell powertrain gave the designers “the opportunity to redefine the classical typology and architecture of the truck.” Sleeper, day cab and straight-truck versions were reportedly planned.

The truck is powered by hydrogen fuel cells. It reportedly has two stacks and up to eight hydrogen tanks, for a daily range of 600 to 800 miles (966 to 1,287 km). The fuel cell system is reportedly the 95 kW (127 hp) unit used in Hyundai’s cars, with its output doubled for the initial testing. Hyundai said that a commercial version would get a more powerful system.

Maik Ziegler, the company’s head of commercial vehicle research and development strategy, said the concept is hydrogen-only because adding battery power would take up too much space and weight, although the first trucks would include some battery power. The Neptune is described as a second-generation hydrogen truck that follows the Xcient Fuel Cell, which Hyundai is deploying in Switzerland.

It was shown with the HT Nitro ThermoTech, a refrigerated concept trailer from Hyundai Translead. The trailer uses cryogenic liquid nitrogen for cooling, which reportedly holds the load temperature within plus or minus 0.5 °C, with the coolant carried in a tank under the trailer.

“With the first hydrogen-only concept for Hyundai Motor Company’s commercial vehicles, we will start exploring opportunities in the United States commercial vehicle market,” said Edward Lee, head of Hyundai’s commercial vehicle business.