The aim of the hotel, as CEO Hideo Sawada puts it, is a serious one: to be the most efficient hotel in the world. He draws on comparisons with low-cost airlines that "changed how we travel." Two years ago, as hotel prices continued to rise, the CEO (who runs the nearby Huis Ten Bosch theme park) began discussions with robotics and engineering experts with the aim of creating an efficient hotel, one that costs (both fiscally and environmentally) less.

If you thought Hen-na Hotel was a kitschy gimmick, well, that's partly true. (The receptionist is an English-speaking dinosaur and there's a talking tulip in each room.) Still, the bigger picture here is that researchers from Japan's largest, most influential university are involving themselves and testing out cutting-edge green technology, as well as trying to create a space where both robots and humans can move around and do what they want (or need) to do. Robots could help reduce staffing costs, as well as help to run a hotel more efficiently. (To some extent -- human workers are still required -- just less of them). The entire premise might scream wacky Japan, but it's also testing the boundaries of robot-human interaction in the field -- and trying to make a profit as it does.

The Hen-na Hotel is actually Hotel Zero, a proof of concept: Everything that goes down here will inform the next stage. Sawada-san is planning to roll out the Hen-na Hotel concept to two more hotels: another somewhere in Japan, and one overseas, although he wouldn't be drawn to exactly where. "Given the philosophy behind the hotel, the location of the site will have a large effect on what the hotel will look like, how it'll be built." The CEO didn't discount the idea that a hotel could be made inside a city center, while Kawazoe added that design considerations could make future hotels substantially different from this real-world proof of concept. Rents are at a premium in built-up areas.

The layout of the four-building complex is arranged in a way to let air flow through the entire thing. That's important, because there's no air conditioning. Dealbreaker? Given that the hotel is on Kyushu, the hot, humid main southern isle of Japan, that sounds insane. However, while outdoor temperatures reached 93 degrees Fahrenheit, the place was reassuringly cool. That's done through a network of high-end radiator panels, combined with heat-absorbing bricks, special reflective paint and solar panels on the roof, as well as sensors to monitor temperatures down to the individual room. (The architecture team even took inspiration from Japanese tearooms to design roofs at an angle that lets in winter sun, but blocks summer rays.)

The company expects to reduce energy costs by around 30 percent compared to typical hotels and these temperature considerations are a major part of how it'll do that. Those cost savings also tie into how Hen-na Hotel is trying to pitch itself as a clean, stylish-but-low-cost hotel: Amenities are bare minimum, with extras sold in vending machines. Room cleaning only happens if you pay for it or stay for longer than a week, but that all translates to room prices that are cheaper than the local competition.

Hagi-San, another expert from the University of Tokyo, was brought onto the project to "integrate robots and architecture."

There's another crucial design difference in comparison to other hotels: This one isn't only designed for humans. Hagi-San, another expert from the University of Tokyo, was brought onto the project to combine the robots and architectural design of the hotel. "I don't think this combination [of robots and building design], while working to provide a service [to humans], exists anywhere else in the world. ... The problem has been integrating these designs with human-centric ones. For the porter robots, we designed the hotel to include wide paths." Two paths slope around the hotel lobby: One inches up to the second floor, while another follows a gentle decline to guide first-floor guests (slowly, but with their baggage) all the way to their room.

Design considerations dovetail into sensors and infrastructure too, like the hotel's face-detection locks on each room. While you don't need your keycard (your beautiful face will suffice), the design of the hotel had to account for this, with low-power LED lighting located both at check-in (where your face gets scanned in), and next to each guest room entrance. During check-in, the process is distributed among multiple machines, working in tandem with each other. Face-scanning software interacts with the touchscreen console, while directions are delivered (and questions answered) by enigmatic robotic receptionists. The performance of these robots is monitored, and that will inform changes in design in the future.

That's where big challenges likely lie: This was a hotel on opening day, with everyone looking to give the best first impression. How will the hotel handle the realities of day-to-day hospitality? With normal visitors (and less staff around when accidents happen), it's likely to be a steeper learning curve than the inclines on those gentle slopes to the first floor. What happens when kid hopped up on one too many soft drinks consistently gets in the way of the porter robot? Is the drone going to fly through your window? What happens when you just need some air-con? Lots of questions, and plenty of challenges for robotics experts (as well as architects, hoteliers and engineers) to tackle.

Quotations in this article have been translated, condensed and edited.