The distribution
board of 2040

01 Demand945 terawatt hours

In April 2025, the International Energy Agency (IEA) published a report on AI and energy. The electricity used by the world’s data centres is projected to more than double by 2030, reaching about 945 terawatt hours: slightly more than the whole of Japan’s electricity consumption today. The IEA names AI as the main reason for the increase.

Japan’s Seventh Strategic Energy Plan takes a similar view. If data centres and semiconductor plants increase with the spread of generative AI, it states, future electricity demand is likely to rise even with significant gains in efficiency. In Japan, a forecast published in January 2025 by the Organization for Cross-regional Coordination of Transmission Operators projected that electricity demand, which had been falling until fiscal 2023, would turn upward from fiscal 2024 and rise towards fiscal 2034. The reasons given were economic growth and the construction and expansion of data centres and semiconductor plants. The Agency for Natural Resources and Energy projects electricity generation in fiscal 2040 at around 1.1 to 1.2 trillion kilowatt hours.

02 GenerationMade on roofs and walls

The way electricity is generated is also changing. The same plan sets a target of introducing about 20 gigawatts of light, flexible perovskite solar cells by 2040, so that they can be fitted to the roofs of buildings too weak to bear conventional solar panels, and to the walls of buildings.

Nuclear fusion lies further ahead. The government’s Fusion Energy Innovation Strategy, revised in June 2025, aims to demonstrate fusion power generation in the 2030s, ahead of the rest of the world.

03 DistributionThrough the board, to the room

Wherever it is generated, electricity follows the same route when it is used in a building. It is received at the receiving and transforming equipment, sent to each floor through the main feeders, divided into circuits room by room at the distribution boards, and carried by the wiring to the outlets and lights. Electricity made by solar cells on the roof or walls also passes through the boards and wiring inside the building. A distribution board holds a row of breakers, one for each circuit, deciding which room the electricity goes to.

By law, the work of connecting that wiring is restricted to qualified people. The Electricians Act, passed in 1960, provides that electrical work in homes and small shops may be carried out only by holders of a Class 1 or Class 2 Electrician licence, and electrical work in factories and buildings with a maximum demand of less than 500 kilowatts only by holders of a Class 1 licence.

04 FunabashiIn schools, civic buildings and UR rental housing

Takane Electric does not build data centres, perovskite solar cells or fusion reactors. Its work is on the receiving and transforming equipment, lighting and power systems of schools, civic buildings, a Japan Maritime Self-Defense Force base, and UR rental housing and prefectural housing in Chiba Prefecture. The Engineering Headquarters’ service guide lists the installation and maintenance of extra-high-voltage receiving and transforming equipment.

The Regional Division’s work includes voltage changes alongside lighting and air conditioners. When a room uses more electricity, the wiring and boards are altered to match.

The company pays the full cost of national qualification exam fees and training courses. Every morning, staff leave the head office in Matsugaoka, Funabashi, for the sites in company vans; there are no transfers.

Even when the unit is the terawatt hour, at the point of use electricity is divided into individual circuits. The circuits on a classroom’s distribution board are among them.