Do you know where approximately 40% of スポーツ ベット テニス CO₂ emissions in Japan come from?
They are actually related to construction. Close to 80% of construction-related emissions comes from energy consumed in operating buildings. In other words, スポーツ ベット テニス use of lighting, heating, ventilating, air conditioning, and elevators results in a massive amount of CO₂emissions.

Converting Electric Power Generated from Solar Power to Hydrogen

Tsuyoshi Nozu of スポーツ ベット テニス Shimizu Institute of Technology came up with this idea one day when he was thinking about a mechanism for reducing CO₂ emissions from buildings as much as possible. He thought, “I wonder if hydrogen energy could produce enough electricity to operate buildings.”

Hydrogen (H₂) produces electricity and water (H₂O) when subjected to a chemical reaction with oxygen (O₂). スポーツ ベット テニス opposite basic principle of that reaction is that hydrogen can be produced through スポーツ ベット テニス breakdown of water into hydrogen and oxygen due to an electric current passed through スポーツ ベット テニス water. If solar power or some other form of renewable energy is used to generate スポーツ ベット テニス electricity for this, no CO₂ will be emitted in スポーツ ベット テニス hydrogen production process.

スポーツ ベット テニス Hydrogen energy utilization system was built from スポーツ ベット テニス thought process of wondering if CO₂-free hydrogen^*1 could be used in building energy management in スポーツ ベット テニス same manner as gas or electricity.
To summarize this concept, hydrogen is generated by using surplus solar power (from water through electrolysis). スポーツ ベット テニス hydrogen is then stored in a metal hydride tank, and released as needed to generate a chemical reaction with oxygen in スポーツ ベット テニス air and produce electricity and heat.
Achieving this would make massive reduction of CO₂ emissions from building operation possible.

*1CO₂-free hydrogen: Hydrogen produced from renewable energy.

スポーツ ベット テニス Hydrogen Technology Group in スポーツ ベット テニス Energy Technology Center at スポーツ ベット テニス Institute of Technology, which is headed by Dr. Nozu, worked on スポーツ ベット テニス preparations for experimental testing on スポーツ ベット テニス assumption of installing to a building with total floor space of around 1,000 m².

How are large amounts of hydrogen stored?

スポーツ ベット テニス hydrogen storage method was スポーツ ベット テニス challenge confronted in designing a workable hydrogen energy utilization system. A large-capacity tank would be needed to store hydrogen in a gaseous state, and this naturally would increase スポーツ ベット テニス amount of storage space. Moreover, hydrogen also presents スポーツ ベット テニス risk of explosion, and this could lead to massive damage if hydrogen stored under high pressure should leaked inside a closed building and ignited.

スポーツ ベット テニス key to solving this challenge was スポーツ ベット テニス hydrogen storage alloy that AIST has been researching. Hydrogen storage alloy has a high energy density per unit volume (it can absorb and store hydrogen up to 1,000 times its volume), and this enables storage of a large amount of hydrogen in a small space.
スポーツ ベット テニス safety issues were solved by figuring out スポーツ ベット テニス composition of スポーツ ベット テニス hydrogen storage alloy. Hydrogen storage alloy gives rise to スポーツ ベット テニス phenomenon of hydrogen embrittlement in which スポーツ ベット テニス storage and release of hydrogen causes it to become brittle and fracture into small particles. Repetition of this process produces a powder that is easily ignited.
Shimizu worked with AIST in searching for スポーツ ベット テニス ideal combination and, after countless attempts, succeeded in creating an alloy that would not break down into easily ignitable particles while still maintaining スポーツ ベット テニス ability to store and release hydrogen.

altThe tubes labeled 2 show スポーツ ベット テニス hydrogen storage alloy before hydrogen storage; スポーツ ベット テニス tubes labeled 1 show スポーツ ベット テニス hydrogen storage alloy after repeated cycles of storage and release. スポーツ ベット テニス newly developed hydrogen storage alloy (tubes with blue tape) show スポーツ ベット テニス characteristic of not breaking down into fine particles after repeatedly storing and releasing hydrogen. Because it does not ignite, it is not classified as a hazardous material under Fire Service Act.">

Results from 10 Long Months of Experimental Testing

Having succeeded in developing スポーツ ベット テニス ideal hydrogen storage alloy, Shimizu finally began experimental testing in June 2017. During スポーツ ベット テニス experiments which continued for about 10 months, we used Smart BEMS^*2 to examine solar power generation and スポーツ ベット テニス building status based on actual data on スポーツ ベット テニス electricity and heat demand for スポーツ ベット テニス building to monitor and control スポーツ ベット テニス production, storage, and release of hydrogen. More specifically, スポーツ ベット テニス excess power generated during スポーツ ベット テニス spring and fall was converted into hydrogen and stored, then used for air conditioning and heating in スポーツ ベット テニス summer and winter, with スポーツ ベット テニス goal of securing efficient energy management technology.

*2Smart BEMS: An energy management system for buildings developed by Shimizu. This system enables comfortable and efficient energy savings through integrated optimal control of distributed power sources and スポーツ ベット テニス equipment in various buildings.

Fuel cells also generate heat when using hydrogen to generate electricity. We realized that this system is especially well-suited to buildings that require a large amount of hot water, such as hotels and hospitals.
In スポーツ ベット テニス performance testing of スポーツ ベット テニス hydrogen storage alloy, we repeatedly stored and released hydrogen through about 1,000 cycles. スポーツ ベット テニス hydrogen storage alloy only degraded by a few percent despite this. Dr. Nozu revealed his confidence in its durability with スポーツ ベット テニス comment, “it appears that it can operate with no problem for 10 years when used in a normal operating cycle.”