Reisen story

Energy Management at Reisen Hutte

Reisen Hutte, with no access to public utilities, must generate its own electricity, gas, and water. This presented us with fundamental questions: Where should our energy come from? What kinds of energy do we really need? With no clear roadmap, we decided on one principle from the start—to move forward with an agile mindset. By “agile,” we mean staying responsive and adaptable to changing conditions. We chose lightweight, flexible initial systems so we could improve or replace them later if more efficient or sustainable options became available. This approach allowed us to maintain adaptability while moving toward our goal of complete energy self-sufficiency. And so began our journey toward making Reisen Hutte a truly off-grid mountain lodge.

Water, Sourced from the Cold Spring Itself

As the name suggests, Reisen Hutte is located right in front of a natural cold spring. We use this spring water for all non-potable needs—such as the bath, toilets, and general cleaning. For drinking and cooking, however, we currently transport fresh water in tanks from the base of the mountain. At first glance, this may seem like a sustainable system. But in truth, the vehicles used to haul the water still emit exhaust gases. Looking ahead, we hope to gradually reduce even this environmental impact. One of our goals is to develop a way to safely filter and purify cold spring or rainwater into drinking water. It’s a challenge we’re taking on through ongoing experimentation and small steps.

Our Heat Sources: LP Gas and More

Mount Norikura is known for its heavy snowfall—up to 10 meters in winter—making it a true snow country. In the early planning stages, we aimed to use a combination of solar water heaters and LP gas. But we soon faced a key question: Would solar heaters even work in such a cold climate? There were concerns that water pipes might freeze, so we began operations using LP gas only. Technically, LP gas can heat the cold spring water. However, the high mineral content—especially iron and sulfur—in the spring water began to damage the high-performance components of our water heaters. Sensors malfunctioned, and equipment failures became frequent. In response, we switched to simpler, more robust water heaters. And thanks to government subsidies, we are now in a position to reconsider installing solar water heaters as originally planned. As of March 2024, we’ve officially begun exploring a hybrid system combining solar thermal heaters and LP gas. Interestingly, Norikura Highlands was the first area in Japan to be designated a Zero Carbon Park by the Ministry of the Environment. This status makes it easier for us to receive support for decarbonization projects, giving us a strong tailwind as we continue to explore efficient, low-impact energy solutions.

▼More about Norikura Zero Carbon Park

Generating Power from the Sun — at 2,100 Meters

In the early days after reopening, our electricity came from large batteries typically used for outdoor activities. For lighting, we relied on rechargeable portable lamps. To keep the batteries charged, we had to drive down to the foot of the mountain twice a day—a process that consumed time, energy, and fuel, and also weighed heavily on us from an environmental perspective. But in autumn 2023, everything changed. We installed Roof-1 (monochrome), a solar panel system integrated directly into the roof, along with Tesla’s Powerwall, a high-capacity storage battery. With these upgrades, we eliminated the burdens of constant recharging—and the psychological strain that came with them. Thanks to solar panels built to withstand the heavy snow typical at this altitude, we’re finally able to make the most of Reisen Hutte’s unique location at 2,100 meters. Looking ahead, we aim to go fully electric by eliminating gas use altogether. Our next challenge is to explore micro-hydropower using the cold spring and the mountain’s natural elevation. This would allow us to generate energy even when sunlight is scarce—moving us closer to a truly self-sufficient, off-grid operation.