On February 20th, Tokyu Corporation, Tokyu Corporation R&D Center, and The University of Electro-Communications announced the continuation of their snow-powered energy generation pilot project in Kutchan, Hokkaido.
This initiative, part of a comprehensive partnership agreement aimed at developing a sustainable resort, builds upon efforts from fiscal year 2024.
A Stirling engine is a type of heat engine that operates on a closed-cycle regenerative thermodynamic process. Unlike internal combustion engines, which burn fuel inside the engine, a Stirling engine relies on an external heat source to create a temperature difference between two chambers.
The above 20-minute video from Greenhill Forge’s YouTube channel explains what a Stirling Engine is and then goes on to build a demonstration device.
How the Stirling Engine works in the Tokyu experiment
Heating & Cooling: One side of the engine is heated (using sources like solar, biomass, or in this case, antifreeze warmed by renewable energy), while the other side remains cool (cooled by snow in this experiment).
Gas Expansion & Compression: A working gas (usually helium or air) inside the engine expands when heated and contracts when cooled.
Piston Movement: This expansion and contraction cycle moves a piston, which generates mechanical work.
Electricity Generation: The mechanical work can then be converted into electricity using a generator.
Why it is useful in this project
Efficient: Stirling engines work well with renewable and waste heat sources.
Quiet & Low Maintenance: Since they have fewer moving parts than combustion engines, they are quieter and require less maintenance.
Eco-Friendly: No combustion means lower emissions and a cleaner energy process.
In this specific experiment in Kutchan, the Stirling engine is using renewable heat sources (solar and biomass) and cold snow to generate electricity while also helping with snow melting and water collection.
The current experiment is scheduled to run from January 9 to February 19, 2025.
Advancing energy efficiency and snow management
During the 2024 trial, the system's engine output was significantly increased from 1.0 kW to 7.0 kW, enabling a maximum daily electricity production of 168 kWh.
Given that the average household consumes about 14.2 kWh per day during winter, this means the system could power approximately 12 homes.
The latest experiment incorporates a new design aimed at melting snow directly from the roof of the facility housing the generator. Additionally, it introduces a system for collecting and filtering meltwater, potentially addressing local water scarcity challenges.
Sources:
R.E. Port News (Japanese only)
Tokyu Fudosan Press Release (Japanese only)
