Vienna plans world's tallest wooden skyscraper (Guardian)

It's 84 metres tall and built of wood to reduce carbon emissions. The fire brigade is a little worried though. Read the Guardian article here.

More details and insight in Wooden skyscrapers could be the future of flat-pack cities around the world, which mentions "plyskyscrapers" around the world. It makes no mention of Japan, home of the world's oldest and for a few hundred years the world's biggest wooden buildings, both in Nara. This is surprising for a country with such a massive building industry and huge forest, as well as great pride in woodwork. You may think it has something to do with earthquakes, but the article mentions wooden buildings being used in rebuilding Christchurch, New Zealand, after the quakes of 2010 and 2011. Maybe that's another area where the image of Japan as a high-tech utopia is at odds with reality.
And if you want more information and some worked examples, here's a 200-page book by Michael Green: The Case for Tall Wood Buildings  

Smart grid - maybe smarter if not everything in it is smart

On the other hand, if you're looking at a neighbourhood with lots of houses with solar panels on their roofs, you may not want them all to be at the optimum angle and orientation. If they're all the same, you're going to get one peak generation, probably around lunch time.

If some are pointing more to the east, and some more to the west, then each will peak at a different time, helping to balance the supply. A roof at the optimum angle will produce the maximum output over the year, probably peaking in May and September when the angle of the midday sun is close to the average for the year. Shallower roofs will produce less in the winter and more in the summer, so a range of angles may also help to balance the supply.

And there may be more levelling of the emerging grid with different kinds of panels, with their performance depending on the weather conditions. For example mono crystalline will produce more electricity than other panels in low light and in high temperatures.

So thinking of the bigger picture, and thinking long term when solar panels are so cheap that people can't afford not to put them on their roofs and they want to switch the big power stations offline, all those arrays at non-optimal angles make a little more sense. And anyway, going fifteen degrees either way from the ideal due-south 35 degree inclined plane is not going to make a huge difference.

Low Energy Building - a fifteen week course

From October I'm teaching a course on low-energy building, ninety minutes a week for the fifteen-week semester. I just submitted a syllabus and am waiting for some comments and corrections to come back. It went something like this:

Buildings use over one third of all energy consumed in Japan, as in many other developed countries. In a world of increasing population and limited fossil fuel reserves, reduction in building energy consumption is important. As well as drastically reducing consumption, low energy buildings can be more comfortable, more healthy and cheaper to run. 

This course will introduce students to the principles, practicalities, and the future of low-energy building. 

...

The course will introduce some simple scientific principles and their effect on buildings. We will also look at the design process, and compromise, optimisation and guesstimates. 

Here is an outline of the course. This may change depending on the needs and interests of the class.

1. What is a low-energy building?
2. What is energy?
3. Insulation and thermal envelopes
4. Windows
5. Energy standards and low-energy building around the world
6. Economics and ecology, Embodied carbon and Life Cycle Analysis
7. Thermal bridges and thermography
8. Ventilation and airtightness
9. Heat and moisture
10. Some examples of low-energy buildings
11. To zero energy and beyond: Buildings as solar generators
12. Heating, domestic hot water and other energy hogs
13. Retrofitting and the future
14. Calculation, simulation and measurement
15. Review

I was going to add this lesson: "Policy making around the world" but it looked a bit boring. 

Also in the syllabus I wrote something about the class being in English, but that questions, presentations and homework in Japanese would be fine. I'm hoping that the class will attract students who are good at English, and students who are interested in low-energy building, but worry that there may be a vanishingly small group who are both! 

And the class is going to be open to members of the local community as well as students.

In the first lesson, I hope to discover the knowledge, preconceptions and expectations of the students. Also I'll introduce the key concepts of low-energy buildings and main factors affecting energy use. 

There are another few months to think about the other fourteen lessons.

What did you get for Christmas?

One of the lowest electricity bills ever! At least the part of the bill that shows how much they pays us. December had all the wrong weather, and our earnings dipped under 30,000 yen for the first time. Six thousand yen less than the previous low in December 2012.

The first three years of our solar enterprise have been going well otherwise, and even this low monthly income was three times what we paid for the electricity we used.

In terms of energy use and generation is we're producing more than we're using, even in the lean months. 

So we could unplug from the mains and have more than enough energy for our needs. We're not in a hurry to do this, as it makes much more financial sense for us to sell all the electricity we produce in the day, and buy electricity at night. And at the moment we have no storage facilities, so we wouldn't really be able to. At some point I may calculate how big a battery we would need to keep enough electricity. The only useful data I have now is the number of days per year when we consume more electricity than we produce, which is under 50, or less than one day per week. Most of these days are between November and March. That data is not particularly useful: we don't need to store power for average situations, but for extreme situations, such as cold winter nights when our power source has been covered with snow for a couple of days, and it's dark anyway.

The amount of storage we need is a complex and exciting calculation, but for now we are connected to the electricity grid with cheap, night-time rates, and getting five times more for the electricity we sell in the day time for another seven years, so I'm not in a hurry to work out how big a battery we would need. 

Thanks for the card, Michael!

A passive house in Karuizawa

Another passive house in Nagano prefecture, this time in the much cooler city of Karuizawa. There are some great points in this interview. One interesting comment is about the trade off between the high installation and low running costs of low energy buildings, compared to the lower initial cost and higher running costs of buildings using fossil fuel energy. Since most people borrow money from the bank to build, the actual initial costs to the owner of the house are very low, since the bank will pay for them. Effectively there are two sets of running costs: utility bills and loan repayments. Since people in Japan can often get low-interest 35-year loans, the loan repayment is a fixed cost. On the other hand, the utility repayments, at least the fossil fuel component of them, seem very likely to rise for the foreseeable future. 

https://catforehead.wordpress.com/2014/10/31/passive-houses-a-conversation-with-kevin-meyerson