Here are brief contents of the talk, which veered seemlessly between Physics lesson, ecological call to arms, and rant about the woeful state of Japanese building. It seemed to engage and captivate the audience of a dozen or so Japanese men and women in varying stages of middle age.
The talk was on Boxing day, the day after Christmas day, in case you didn't know, and they asked me about that first. I told them that for me Christmas was not at all Christian, and asked them what fir trees and reindeer had to do with Israel. Also I told them how it wasn't even Jesus's birthday; that had just been a ploy by the Christian church to suppress and subsume pagan worship of the winter solstice, and celebration of the sun coming back. This actually began to get onto the topic.
Eco logical or nomic
The bigger TV you get, the more eco points you get. It should be the other way round!
Stick "ECO" on something, and people will pay more for it, and you'll make more money.
Exponential growth of fossil fuel consumption
The vicious circle of increased efficiency, leading to increased consumption, leading to more money coming in, leading to improvements in efficiency. This is counter intuitive, but the record with coal is that improvements in efficiency, rather than reducing consumption, exponentially increase it. Has our economics moved on?
Engineering
Among my studies were electronics, thermodynamics and finite element analysis. Not particularly useful in language teaching, but they have been very helpful in building my house.
Traditional Japanese building
Much better than modern Japanese building at stopping overheating in the summer. But what about winter?
I talked about a new paradigm in building
We need to stop using fossil fuels
Insulation materials are available
Ventilation systems are available
Better window technology is available
At this point I had to persuade them that the standards in Japan are very low, and though there may be some houses with some insulation now, it is not a lot.
Common confusions
I talked about heat and temperature. Outside it was five below freezing, but there was a lot of heat, as it was still over 200 degrees above absolute zero.
Energy efficiency or energy use. I told them about my car, which is one of the most environmentally friendly cars in town as I hardly ever use it. It has terrible mileage though
"It's good for the environment"
Almost nothing humans do is good for the environment. Some things are just less bad.
Insulation.
People often think that things either insulate or don't. In fact some things just insulate better.
Passive house
This is an answer and a goal in building a house. It constitutes:
Very high insulation, including windows;
Very airtight, so it needs a ventilation system;
A heat exchange ventilation system, so you don't loose all the heat in the exhaust air;
Maximised solar gain, so the windows are on the south
In Japanese this is often called「無暖房住宅」(mudan-jutaku: non-heating house)
The idea in Europe was that with these criteria met, central heating is not necessary, as the appliances and bodies int the house are enough, or the incoming air can be given extra heat within the ventilation system. Central heating has been standard in Europe, although they are now trying to get away from it. In Japan, on the other hand, it is a recent development that progressive builders and up-market buyers are installing.
Good insulator
Thicker is better
No gaps!
I showed them the pictures of the heat sink and the part of the window frame. Most of them guessed which was which, but it was quite difficult, which was my point.
I asked what the best insulator in the room was. One of them correctly identified that it was air. I found out later he had a PhD in biophysics.
Eco points!
The house did get lots of Eco points, it was 200% of their low energy standard, at 0.92 W/m²K (watts per square metre of floor space per degree difference with the outside temperature). A figure which I need to check.
To translate this into terms that they could easily relate to, I told them yesterday morning it had been -8°C outside, and it was 14°C inside, and the underfloor heating is not working yet. My old house would have been the same temperature with the heating on.
LEDs
The advantages are: low energy, they don't radiate heat, they're small, long lasting and don't attract insects. They asked why, so I explained that LEDs produce light in the spectrum visible to us, whereas insects are really only interested in animal blood, so they want to see warm bodies with lower frequency infrared vision.
The problems with LEDs are: they can't dim, they have limited colours and they're expensive. Actually the first two are not correct, and the last one will be less and less so, as costs are going down exponentially.
Solar Power
The advantages are: no fuel, no pollution, no noise, long lasting. The problems are: cost, area and unreliability due to clouds.
Power democracy
I put it in terms of a model of individual ownership of the means of power production, rather then governments and big businesses, who will build a nuclear power station North of Tokyo, and go on holiday in the resorts South of Tokyo.
I left them with these questions:
Would you live under an oil power station?
Would you live under a hydroelectric power station?
Would you live under a windmill?
Would you live under a solar power station?
