​Eight weeks is a short time in housebuilding

Finally we have two working external doors.

I wrote about our unhinging problems back in May, at which point they had already been troubling us for a couple of months.

The broken top hinge was a particular worry, as our heavy front door was now just hanging on two out of three hinges, and there was a risk that another hinge would break and the door would land on somebody's head.

The people who came to install an inside door noticed this problem, and we got in touch with Wald at the end of March. I'm not sure what happened in April. It tends to be a busy month. At the end of May they put us in touch with  Yamazakiya Moko who make the best wooden windows I've seen in Japan. They visited on 5th June. They said they'd try to get in touch with the manufacturers of the window, which I suggested would not work because they had gone out of business.

As well as looking at the door problems, I showed them our more chronic and less critical big window on the South, and the leaky part at the bottom between the second and third leaf. He fairly quickly noticed that there was only one point along the bottom of these two leafs fixing the door when it was closed, and suggested that adding some more would be a good idea.

Anyway, confidence inspired, I looked forward to my front door getting a new hinge, and waited for a reply.

And waited.

I'm probably not pushy enough, and I know I'm not the most active of correspondents, but I did telephone on 18th July, and he said he was waiting for parts.

I got in touch another couple of months later, and finally got a reply back 29th September saying that without any contact from the supplier, they wouldn't be able to do anything. I wrote backing telling him that I had known the manufacturer wouldn't get back to them six months ago.

So I started exploring other routes. The two options seemed to be to find another person who could fix the door, or do it myself. So I started working out what the part was, and looking for it online.

I got in touch with the importers of our windows to see if they had any other ideas. They responded very quickly, and sent someone around. But they are importers and not fitters, so they said they'd have to get in touch with the company they worked with. Yamazakiya. I explained that I was already in touch with them, so they told me to wait for them to get back to me. October also gets pretty busy, but I wrote to the Passive House lady on 11th October. And wrote to Wald again a bit later.

On 22nd October I wrote to G-U, Gretsch-Unitas, who make these and probably a majority of high-spec window hinges in Germany, asking if they had a Japanese supplier, or if there was anywhere in Europe I could order these parts online.

The Passive House lady was in Japan, and she went to visit Yamazakiya, finding out that the problem was in getting the parts. I had assumed that getting parts would be easy. I realised that when Yamazaki had talked about the manufacturers, they were talking about parts manufacturers, not window manufacturers.

On 17th November I went to visit the Japan Home Show, where I noticed by chance Yamazakiya were exhibiting, so I went to visit their stand and had the chance for a quick chat, which I think helped remind them I'm a real person.

On 22 November I got a message from MSH Co., Ltd, an authorized distributor and the sole agent of G-U in Japan. They apologised for being so late replying to us, "since the articles in question are not treated as single parts in Japan, nor we have handled them before." But they did find part numbers, and told us we needed to specify whether the hinge was on the right or left. The good news was that they could supply the parts, but the bad news was that they could only supply 10 parts of each which would take around a month to get here, and they would charge 50,000 yen. "Please consider and let me have your reply in case you want to go ahead."

This seemed like a lot of money when I only wanted one bit of metal, but at least it explained the lack of progress from Yamazakiya.

Surely there is a way of getting this part cheaper in Europe? Well our window importer spends part of the year in Europe, and has contacts with European window manufacturers, so that seemed like a good person to get back in touch with.

By now, it's the end of January, 2018.

Once again there was a fast response, and a lot of initial positive noises although it's important to remember that Europe essentially has a four-day week because their weekend starts Friday lunchtime. I think this is an excellent thing, but it does require some concentration. I already knew that European businesses didn't do August, and you'll notice that month also missing from this timeline.

Reports then followed of potential wholesalers, parts in stock, numbers of parts required, prices, higher prices, no parts in stock, and eventually a higher price than MSH in Japan was charging for ten parts. Apparently this hinge is no longer used in Germany, and as a hinge for an out-swinging external door, it was probably rarely used in the past.

So on 8th February I got back in touch with MSH in Japan and asked how much they would charge just for the hinges and not the latch plate. I could get a single latch plate online from www.slotnodig.be, a supplier in Belgium for around 20 euros, so there was no need for me to order ten. He told me that would be 45,000 yen, but stressed that did not mean he would sell me ten latch plates for 5,000.

I reminded him that I didn't want ten latch plates, I only wanted one. And for that matter I didn't want ten hinges either.

He then seemed to get a bit defensive and told me that the maintenance and replacement of fittings should be carried out by the manufacturers of the windows or doors, because their condition depends on the quality of manufacturing, and that inappropriate manufacturing or installation will lead to elements breaking.

He also said they had to respect G-U's ''Unit Package'' of ten pcs. They had never purchased or sold this part in Japan before, did not expect to sell any in the future, and did not want to hold any on stock, and that they were giving me special treatment.

I was left feeling that the customer care at GU did not care much about customers. Also this highlighted my own unenviable situation. The manufacturer of my doors has gone out of business, so what am I supposed to do? The fact that the parts broke suggests at least a possibility that there was a problem with the quality of manufacturing, and I imagine that is the usual reason for parts needing to be replaced.

So around 9th February I ordered ten hinges from MSH, and ordered one new latch plate through www.slotnodig.be, which was great practice for my Dutch web skills. The latch plate was shipped 13th February and arrived around a week later. I was worrying that the hinges would take much longer, but they got to the MSH warehouse 19th February and were sent straight to my house.

Teaching Low Energy Building: Final Answers

Here are the answers to the final questions of my low energy building class.

1. The top priority for a low energy building is insulation.

Not solar panels, the latest electronic equipment, increasing the number of windows or planting grass on the roof. All my students got the right answer. They were 100% successful. In educational assessment terms, this question was 0% successful in discriminating between students. But I'm not so interested in discrimination. Just happy that all of my students got the main idea of the course, which is that insulation is the top priority in low energy building.

I could probably have put some tougher distractors in there, like mechanical ventilation with heat recovery, air tightness, good form factor or avoiding thermal bridging. Perhaps I should make a more difficult question next year.

2. Half the students got the next question completely right; eleven out of twenty-two taking the test.

This question did a much better job at discriminating!

This was a real-world low-energy building question getting them to choose the amount of insulation needed depending on the windows they were using. It assumed an energy budget for a small house of given surface area and floor area, and a fixed requirement of window area.

The question was made more tricky since they had to choose insulation thicknesses rounded to the nearest five or ten centimetres, as you tend to get in the real world. Also, in the real world, you need to round up rather than round down when you're trying to meet this kind of target. This may have thrown a couple of them.

Even worse is question 4  

As a language teacher, I usually despair at closed question, especially multiple choice questions where language is polarised into one correct answer and three incorrect ones. In the case of insulation, there are genuine discrete choices since the insulation comes in standard sizes. You can't buy 17.4 mm thick sheets, however much the calculations tell you that's what you need, although you could blow-fill a cavity of any thickness you like. The choices I gave in my test—15, 20, 30 or 40 cm of nano-porous super insulation—are almost a factor of ten thicker than the options given for Neomafoam by Asahi Kaisei, so I guess the choice would be something like two sheets, three sheets or four sheets thick.

Also, this was a matching question, with four different U values of window and five suitable insulation thicknesses to choose from. Obviously the eleven people who got the correct answer all gave the same answer, but the other eleven were each wrong in a different way.

One piece of low-hanging fruit was that with single-pane aluminium-framed windows, it was impossible to make walls thick enough to stay within the energy budget, and 19 out of 22 students got this bit.

At a conceptual level, the better the windows, the less insulation is needed in the walls, so the lower the window U values, the thinner the walls can be, and 16 of them got this in their overall answers, although two of them missed the answer for the single pane windows. A couple of them were choosing progressively thinner walls for higher U values, but both of them got the right answer for the single panes.

As for the other six students, it's difficult to be sure what they were thinking. They may have just been looking at the materials and assumed that wooden windows were better than PVC. They may have miscalcalated and not been thinking of the answers with top-down reasoning.

Anyway, I think the correct answers are:

• Two times thinner (around 40cm) for U 1.7 Double, low e, argon, wood frames;
• Three times thinner (around 30 cm) for 1.3 Triple, low e argon, PVC frames:
• Four times thinner (around 20 cm) for U 0.8 Triple, krypton, insulated wood frames;
• You can't make walls thick enough for the single pane windows (U 6).

3. I told you the coffee maker question before.

A one kW coffee maker in a teachers room, left on for 90 minutes, twice a day, five days a week, with a possible replacement for 10,000 yen with a thermos flask pot. How many weeks till the new pot pays for itself in electricity savings at 25 yen per kWh?

Fifteen of them got the right answer. One gave the precise answer of 26.7 weeks, but I was pleased to see most of them rounding it to the nearest week. Seven people rounded up and seven rounded down. Strictly speaking the ones who rounded down were wrong, both because rounding up is closer, and because you still haven't paid for the new pot yet. One person got half marks for giving 30 weeks. In a way, that's a better answer than the more precise 26.7. 

A couple gave 40 weeks, the shortest answer was 3 weeks, and the longest 250,000 weeks, which will take us to the year 6825. I'm not sure whether people will still be drinking coffee then.

Feedback on low energy building course

There is a well established process for running projects, and many other human endeavors, with acronyms like PDCA, standing for plan, do, check and act. Or adjust. Or again. Whatever the last A stands for, equally well established is the habit of forgetting that last bit. People love the planning, they enjoying the doing, they reluctantly dabble with checking, and have lost interest when it comes to strategic changes. The next time around, they will do things the same way, perhaps with a little less emphasis on the bits they don't like doing. But those little tweaks and readjustments are often the difference between long-term success and short-term failure. 

So this is me checking and adjusting my syllabus for the low energy building course, and I'm actually trying to use the student feedback in the same way feedback is used in control engineering rather than the frantic rush to turn down the volume you get in amateur sound engineering.

Feedback came from two directions: one in the form of paper questionnaires handed down from the university and handed out in class. For the most part students just pencil in the lozenges somewhere between strongly agree and strongly disagree, but I encourage them to fill in the spaces for written comments. In one class I told them they should write something about the paper questionnaires being a waste of time, and the university should administer them online. Four of the students did write something like that, and while I was pleased, it shows that students in the classroom will just write what the teacher tells them to, which is just one of the reasons paper questionnaires should not be completed in class. 

That was a different class though. In the low energy building class, their comments mostly just
reported that they had learnt about low energy building. Important knowledge about low energy building. Knowledge about the importance of low energy building. A couple just said they learnt about buildings, which is perhaps an even better response. One person said it was important to think about economic issues as well. Another valued the fact that the lesson was in English. Most of these comments (70%) were in Japanese, the same language as the university questionnaire, but nobody commented here that I should speak more Japanese, or that the class should not be in English. 

The other formal avenue for feedback was in the final questions, where I asked them these two questions:

• What was missing from the course? What other topics should have been covered, or what topics should have been covered in more depth?
• How can the course be improved? How can I make it better for next year? 

I know the pedantic grammarian will find four questions there, but I rephrased each question to make it clear what I wanted to know, and also because the length of answer is often proportional to the length of the question since the human tendency for mimicry is much stronger than the tendency for following instructions. Almost all of the students (90%) answered these English language questions in English.

Six of them mentioned language in their suggestions for improvements. Three suggested I should speak more Japanese, one saying an all-English class was a bit difficult. One suggested adding definitions in Japanese on the slides. Two wanted the students to speak more English, one of them suggesting students should only speak English in class, the other saying her English had become more fluent and that I should continue to English. 

Conclusion on language: Using theories to determine thermal comfort in buildings, it seems the language temperature of the room is OK, judging by the relatively small number of people who are too hot or too cold. Adding definitions in Japanese to the slides is a great idea that I need to do more.

I was worried that I'm doing too many calculations, but it looks more like the opposite. Seven people mentioned calculations, mostly wanting more time to do calculations, or wanting me to spend more time on them. They mentioned U-values, windows, compound insulation and calculating whole-house U-values.

In terms of course content, four wanted more case studies, one asking about low energy buildings in Matsumoto, and two wanting more information about low energy buildings in other countries or about international differences.

Three wanted to know more about insulation materials.

Two mentioned cooling, which I know is an important topic that I should have covered. I just realised that lesson 5 started off as a lesson on cooling, but now seems to focus mostly on comfort. I think the windows from the previous lesson may have spilled into it. Also I had prepared a full lesson on cooling, which I then did not teach.

Two wanted to know about the latest technology, one asking about the latest building techniques, the other giving the example of dye sensitized solar cells.

Other content suggestions were for Passivhaus in more depth, hydroelectricity, window frames, and large scale energy savings, for example at the city scale.

​Other comments were ​more about the delivery and presentation of the class.

Four people gave positive comments on the course​:​ that it was great, perfect, nice, or had a good balance.

Three people gave somewhat critical comments: I should make my slides better, I should ask what students want to know, and I should introduce an expert on low energy building to the class.

Actually the last one is probably not critical, and I should take it as a positive suggestion, and in fact a really good idea. They may mean that I should be talking about low energy building experts rather than physically introducing one in the classroom. Just because that's how I would have written "you're crap" doesn't mean that is what they meant when they wrote it. While it's great that so many of them are writing in English, there is more chance for ambiguity when they are writing in a foreign language.

(I didn't have this question)

One student suggested that the range of questions in the online tests was different to the content of the class.

One person suggested I should always give measurements for the sizes of windows and rooms. I think this is something I realised half way through the semester, and something that made me think I would get requests for fewer calculations. I tend to give the students real world problems, and hope that they will be able to grasp the problem, identify what information they need to solve the problem, get exact values for the information where they can, and estimate where they don't have exact answers. This is a chain and is only as strong as its weakest link, and most of the students will fall down at some point. What I need to do is to break problems down in a much more systematic way, and give them several chances to practice each step before putting the steps together. I need to carry on giving them guesstimation problems, for example estimating the dimensions of walls or windows, but not at the same time as giving them thermodynamics problems.

Another wanted a list of formulas which we learn in class, which would be a really good idea. I should produce a low energy cheat sheet!

Another suggested that presentations should all be done in one lesson. Interestingly this was from one of the students in the group that went up to speak first, who had specifically said that they wanted to give their presentations in that lesson, a week before all the other presentations.

Finally, there was a comment that I should "distinguish between good and weak students in good balance". I'm not sure what that means. Perhaps that I should be making sure I'm teaching the students at the right level. Perhaps it means they should be working together in groups based on their level.

Now it's back to the drawing board for next year's class! The syllabus needs to be uploaded next week.

Teaching Low Energy Building: Final Questions-part one

Each week ​I've been adding questions on the content of each lesson to an online learner management system called Module. Here are the​ first three​ questions for the final lessons. I'll post the answers next week!

1.​ ​What is the top priority for a low-energy building?

Select one:

Add solar panels

Buy the latest electronic equipment

Increase the number of windows

Plant grass on the roof

Use insulation

​2. ​(This question follows the question in the Windows 2.0 quiz)

You want to build a small house with a heating load under 25 kWh/m2a. The house is 35 square metres, so you want to use less than 875 kWh per year. The wall and roof area of the house is 100 square metres. You want 4 square metres of windows. The house is in Matsumoto where the annual heating demand (G) is 80 kKh (kilo kelvin hours).

If you use U 2.3 windows, they will lose 736 kWh per year. So the rest of the house must lose less than 139 kWh (875-736). The U value of the walls must be 0.017. (U = Q / A G.) Using nano-porous super-insulation material (k=0.015 Wm/K), these walls would be around 90 centimetres thick!

If you use the other windows, how many times smaller are the U values for the wall?

In other words, how much thinner can the walls be?

U 1.7 Double, low e, argon, wood frames	Choose...three times thinner (around 30 cm)five times thinner (around 15 cm)two times thinner (around 40 cm)four times thinner (around 20 cm)you can't make walls thick enough
U 1.3 Triple, low e argon, PVC frames	Choose...three times thinner (around 30 cm)five times thinner (around 15 cm)two times thinner (around 40 cm)four times thinner (around 20 cm)you can't make walls thick enough
U 0.8 Triple, krypton, insulated wood frames	Choose...three times thinner (around 30 cm)five times thinner (around 15 cm)two times thinner (around 40 cm)four times thinner (around 20 cm)you can't make walls thick enough
What about the single pane windows (U 6)?	Choose...three times thinner (around 30 cm)five times thinner (around 15 cm)two times thinner (around 40 cm)four times thinner (around 20 cm)you can't make walls thick enough

​3. The teachers' room has a coffee maker. Usually five days a week, twice a day, someone makes coffee in the break time, has one cup. Then for 90 minutes the rest of the coffee sits in the pot, with the heater on, until the next lesson has finished.

The coffee maker uses a 1 kW heating element to keep the coffee warm.
There is a new coffee machine with a thermos flask pot. It does not need a heating element.
It costs 10,000 yen.
Electricity costs 25 yen per kWh.
If we buy the new coffee maker we will pay less money for electricity.

How many weeks will it take to save the money?


Answer:

​

Future predictions

Here are some predictions based on current trends.

Computer chips will have one transistor per atom in 2025.

Every car will be electric by 2053.


There will be enough solar panels to cover all land on earth by 2056.

Two of these predictions are very likely to be wrong.

The first is based on Moore's law, which predicts that the number of transistors on a given size of chip will double every eighteen months.

The figure for electric cars is based on the recent increase in proportion of EVs, which in most countries is still less than one percent. The proportion may increase exponentially, and will of course stop increasing when it reaches 100%.


The figure for solar panels is based on a compound annual growth rate of 30%, which has been been happening for the past twenty years. I'm assuming that power output per area of solar panel will stay the same, which it probably won't. New panels will steadily produce more electricity for the same area, but the increase will not be large, let alone exponential.

Of these predictions, I think Moore's law is the most likely to come true. This law has held true for fifty years. I don't think atoms will necessarily stop it, since quantum computing is now a thing.

Moore's law has been enabled by the success of electronics leading to a steadily increasing budget for development of ever smaller chips. Developments have tended to compliment each other, rather than replace them. The budget is not increasing at a Moorean rate though.

These exponential growth rates are usually unsustainable since at some point they are limited by physical constraints of the real world. If things are getting smaller, of course, there is no limit. Right now there is a limit to our understanding of the very small, but if science shows us one thing it is that when we ask questions, sooner or later we find answers. The harder we look for the answers, the quicker we find them.

More interesting is Wirth's law, which states that "Software is getting slower more rapidly than hardware is getting faster." So all these improvements in the computer power are eaten up by extra complications and functionality that we don't necessarily need. I noticed this around 1992, and decided to stop spending so much time programming computers. I now wish I'd written a paper on it, like Dr. Wirth.



I'm pretty sure solar panel production will peak before we cover the whole planet, although I will not be surprised to see nature reserves clear cut for solar farms, massive floating arrays, or increased solar installation in space. They may even start making the panels up there. The economic effects of increased solar power will likely be that some electricity is effectively free, which will drive down the price of electricity, and reduce the value of the panels, making their manufacture less worthwhile. So I don't think this prediction will come true. I'm hoping to still be alive, and will be able to find out.

There will very likely be a point in the future when the only people not driving electric vehicles are stupid and rich, and I think this point will come sooner rather than later. By the time our computers are firing on subatomic logic, the majority of people will be buying new electric cars. I'm sure this will sound as ridiculous as someone predicting the wide use of steam trains in 1818, or motor cars in 1918. Also, we must not underestimate the size of the stupid and rich demographic, and its disproportionate political power. There will always be a bit of liquid fuel sloshing around, and we are unlikely to ever have 100% electric vehicles, but I think we'll be close to that long before 2053.

Here's an article from the Guardian about accelerating car sales. Here's another claiming that the electric vehicle revolution in Australia is stuck in first gear. The press is never shy to use motor-industry metaphors, but they don't realise EVs only need one gear. Also they may never have experienced the excellent acceleration of electric vehicles.