There’s an elephant in the tatami room – Japan has absolutely zero mandatory building energy efficiency standards. This nation’s buildings consume about 40% of all primary energy, and about 70% of all electric power. Simply improving building efficiency would dramatically change the electric power demand side of the equation in this nuclear catastrophe challenged nation, and yet there is no building code regarding efficient energy usage.
Japan is no stranger to strict building standards, it has some of the worlds toughest quake resistance and fire proofing building code. For some reason the government has never found it necessary to create efficiency requirements by law.
Many other countries have very strict building energy efficiency requirements. For example, Germany will require all new buildings to be Passivhaus certified by 2015. Other EU countries are also implementing stringent energy consumption building code.
Japan on the other hand, has let the free market reign and the results have been buildings which are incredibly inefficient. Experts have called for improved building envelope insulation performance, double glazed windows, and other improvements for years. The current situation is that even the “Next Generation Energy Efficient Smart Homes” promoted by the housing industry are woefully inefficient compared with modern standards such as Passivhaus or Zero Energy Buildings.
To understand the scope of the problem, modern energy efficiency code could reduce building energy consumption by 80% to 90%. As about 70% of building energy is used in HVAC, water heaters, and lighting, efficiency code could reduce a huge portion of the nation’s energy consumption as well as green-house gas emissions. Building use more energy than industry or transportation. Buildings are by far the largest consumers of energy.
Further, Japan’s housing stock has a typical lifespan of only 35 years, other larger buildings are usually replaced every 50 years or so. Japan’s older buildings could be replaced very quickly compared with other nations which have longer lasting building stock. For example, about half of all of Japan’s homes will be replaced over the next 17 to 18 years.
The situation hopefully will change. The Ministry of Land, Infrastructure, Transport, and Tourism (MLIT) announced vague plans to create mandatory building energy efficiency standards by 2020 – some eight years from now. Hopefully the ministry will not try to re-invent the wheel regarding the standards and will implement world leading standards rather than the weak half-baked current code in place.
MLIT also needs to take a look at building refurbishment energy efficiency. More enlightened energy policies in other countries motivate building and home owners to make energy efficient modifications to their properties. Japan currently has little in place to encourage owners to improve to save energy.
I’ll try to write more about this important topic as more information becomes available.