Prime Minister Kan announced today that Japan will embrace energy conservation. While many assume Japan's practices are very "green," this has not been the case in architecture. The turn-around is VERY exciting.
This has been coming for a while. What took them so long?
1) In some ways, Japan has looked pretty good when it comes to energy consumption. The nation's energy-to-GDP ratios, for example, are very good. Japan, with just over 125-million people, had the world's second highest GDP until about a year ago, when China (population 1.3-billion) surpassed it. The U.S. (population 307-million) has the highest GDP. So, if you compare a big number like GDP to numbers like population or energy demand, the nation is awesome.
HOWEVER
Japan has limited energy domestically; it imports. It imports a lot of energy, and it imports a variety of energy. Japan is the world's largest net importer of coal. It ranks 3rd globally in petroleum imports (after the U.S. and China). It consumes 36% of globally traded liquefied natural gas, making it the world's largest LNG importer. And Japan is the third largest consumer of nuclear power, after the U.S. and France--that uranium and plutonium also imported. (For a very scary outline of how this hunger for energy plays out in terms of international politics, go to the U.S. Energy Information Administration country report on Japan.)
And (yep, it gets worse), Japan's consumption of energy has been growing faster than in other developed nations. From 1990 to 2005, the OECD average energy demand growth was 5-9%. Japan's was 15%. The biggest area of growth in demand? Buildings.
2) Energy demand in buildings is rising faster than the other two commonly calculated sectors (transportation and industry), but per capita consumption in this sector also looks surprisingly good.
History plays a role here. In homes, most Japanese still tend to heat or cool only the rooms they are using, not their whole home. The amount of space per person in homes and offices is also less than in more expansive nations, like ours.
HOWEVER
Energy consumption in architecture is rising a lot faster than in other areas: people are living in larger spaces, increasingly they are working and living in settings where heating the whole interior is the norm. AND, to make matters worse, demographics play a part. Society is aging (those over 65 tend to require more energy per person) and households are getting smaller (an individual in a 1-person household consumes about 1.7 times the energy of a person in a 4-person household).
I'd also point out that a lot of international comparative figures are more than ten years old. Much has changed in terms of lifestyle and computer use (just to give two examples) in the last ten years. These changes mean more space per person and more demand at the electrical outlet.
3) You'd think that with all that importing, the nation would have decided that reducing energy demand was politically wise. But in my field, Japan has tended to drive such decisions by consensus, not top-down regulation. So when it comes to energy, Japan basically has a voluntary building code. That has worked okay with larger buildings, where owners and designers are sophisticated, but not so well with the small businesses and individual owners who commission a lot of the nation's buildings.
There is less economic incentive at the small scale to insulate. Building life spans average about 25 years. That means the "pay-back period" for conservation is shortened. In California, we address this with taxes and subsidies, in addition to strong energy codes for buildings. Japan is reluctant to tax energy aggressively; the subsidies I have seen in architecture often seem to target areas which might yield market leadership in the long run (home fuel cells, say)--and when those subsidies go (as with solar hot water heating or residential PV), there is quite often a dramatic drop in demand, because the initial subsidy was not set based on efficiencies.
Scary fact: in a recent study, an estimated 70% of single-family homes and 60% of multi-family homes in Tokyo had NO insulation--and you'll find similar statistics for much of Japan, except the areas with the most extreme heat or cold.
4) Lastly, since the Kyoto Protocols, Japan has been more focused on greenhouse gases than on energy demand. (It's the world's fifth largest greenhouse gas emitter.) And if you believe that climate change is underway--I do--then that makes some sense. Japan's population is very vulnerable to rising seas.
But sometimes that single-minded emphasis on greenhouse gases has led to strange choices. I'd put the heavy emphasis on nuclear power on my list, but as an architect, that is out of my range. How about this one? I read a report recently, written by many of Japan's leading scholars in energy and architecture, one that came out against insulation. Huh?? Well, Japan tends to use foamboards, what we call rigid insulation. And it appears that there are still Japanese producers who use production methods that both rely on and leak CFCs--greenhouse gases. (Those must be old plants.) So instead of suggesting other forms of insulation (cellulose would make sense, considering Japan's lumber supply), the scholars suggested that increased insulation might not be a good idea. Using a power source with lower greenhouse gas emission made more sense.
Like nuclear power.
Oops.
More ahead: What does California have to offer on this topic? A lot.