ブログを 引っ越しました

ブログを別のサイトに引っ越しました。

新しいブログはこちらです：http://solar-sharing-japan.blogspot.jp/

これからの投稿は全て新しいアドレス↑↑↑になりますのでよろしくお願いします。

これまでの記事も全て、新しいアドレスに載っています。

ココログから引っ越した理由は主に2つです：

１．ブログの管理は私にはやりづらく、投稿が面倒でした（例えば記事のレイアウトで段落間の空白が反映されないこと；写真の管理など）。

２．ココログは日本国内向けのサービスで、日本語以外での発信や海外からのアクセスを全く想定していません。そのため、例えばアクセス情報では日本国内のアクセスしか分らないなど、不便なことが生じます。

上記の点が改善されれば、戻ってこようかなと思っています。今まではお世話になりました。

Blog moved elsewhere

I moved this blog to another site. 

New blog is here:  http://solar-sharing-japan.blogspot.jp/

Everything from now on will be posted on this ↑↑↑ new address.

You can also find all the old articles on the new address as well.

There are two reasons for leaving Cocolog:

1. I found managing blog on Cocolog inconvenient and posting new articles time consuming (basic layout problems like spacing between paragraphs not automatically reflected in final article; cumbersome photo management etc).

2. Cocolog is inherently designed to be used within Japan. It does not assume posting in any other language than Japanese. It does not assume the blog could be viewed in countries other than Japan. This results in several inconveniences, such as access statistics only showing views within Japan, not from around the world. It's not world-wide but Japan-wide. Which is quite narrow.

I hope Cocolog will once decide to fix these issues. Until then, see you on another platform!

Chickens flying

It's been a month since our chickens arrived. In the life of a chicken, one month is a long time. It takes humans several years to grow from cute babies into cheeky school-age children. Chickens can do it in a single month.

They are now less cute or fluffy , but they are  stronger and more independent than before. They have impressive wings and can fly!

This is how our chickens looked when they arrived a month ago (end of April):

And these are the same chickens one month later (end of May):

On the picture above, chickens are sitting on a perch that we just finished yesterday (May 31). Perch was an instant success, chickens love it.

Now we're working on a fence outside the coop so that chickens can play on the grass. As they grow bigger, the coop will soon be too small. Picture below shows the inside of the coop (this picture was taken just before finishing the perch yesterday).

That was a quick update.

Chickens arrived!

Two weeks ago 35 newborn chickens arrived! We've been doing our best to protect them from all sorts of chicken enemies. Many of the confirmed enemies are cats. We've noticed great increase in the number of cats and frequency of their visits to our solar sharing power plant. Cats' favorite place is right in front of the coop, watching what they hope to be their dinner, or breakfast, or lunch, depending on an hour. They are patient, but I'm proud to say that despite enemy's relentless effort and patience, we are winning and there are still 35 chickens in our coop.

Here are our chickens one day after they arrived (that is, they are two days old in this video). They have fluffy bums, cute little wings and huge appetite.

Power generation - performance report

Our solar sharing power plant has generated a lot of electricity since it started operation 5 months ago - precisely 22 952 kilowatt hours in the period from November 27, 22014 (start) to April 24, 2015 (today). That's not bad for an installed capacity of 40 kilowatts.

We use a monitoring service "Solar Monitor" that allows us to check real-time generation status online. Being able to check it anytime anywhere (that is, "anywhere with internet connection") is extremely convenient, and on sunny days it's also quite fun.

Picture below is Solar Monitor screen shot from today April 24, 2015, taken at 17:21. In the circle on the left you can see that the plant was still producing 2 kilowatts of power despite the late hour. That's one of the good things about days getting longer towards summer. From the screen you can see that today a total of 200.4 kWh was generated (for the record, it slightly increased to 201.9 kWh at the end of the day.)

For English explanation check an older screen shot below (click for enlargement):

By the way, the mechanism that allows us to change the panel angle (tilt) has been - as expected - a major contribution to performance.

I never noticed it before but the position of the sun on the sky is really different in winter and in summer. I do remember learning at elementary school that sun is low in winter and high in summer, but I never quite observed the sky to see how different "low" and "high" actually is. Until recently.

In terms of solar power generation, the position of sun has great implications. It means that while in winter you want to lean the panels into very steep tilt (as much as 60 degrees), in summer you want to put them in almost horizontal position (as little as 3 degrees). This greatly affects the amount of electricity produced.

Thanks to the panel adjustment mechanism, we're doing exactly this - optimizing the tilt every few days (or weeks) according to the seasonal height of the sun.

Graph below shows optimal angle of solar panels for each month of the year. The graph is for the location of Hachiouji (Western Tokyo), which is some 100 km from here, but it's the same Kanto region so the data roughly apply to our place as well (observation-confirmed). According to this graph, optimal tilt is 60 degrees in January, 34.5 degrees in March, 2.6 in June and 40.8 in October.

You can find the original graph here:

http://www.solar-partners.jp/pv-eco-informations-32764.html

This was a quick performance report.

Our solar power plant construction in 4 minutes

Here's Part 2 of the video summarizing construction of our solar sharing power plant in Tsukuba.  Given that construction was finished in November last year and now it's already April, the video is badly overdue.

There was another video covering the same topic, which I posted in February, but it was so poorly edited that I eventually decided to remake it. This is the result.

Why was making Part 2 so much more difficult than Part 1? Here's a metaphor to explain it. If we compare construction of a power plant to building a house, Part 1 of this video shows how the very building of a house was made - brick walls, window holes, a roof. At first glance it's a complete house, but in fact it's not habitable yet. It has the shape of a house but there's nothing inside. Part 2 shows how the house is equipped with all the basic amenities that make it a real, habitable house: water supply, heating, electricity, furniture.

Part 1 shows the form, Part 2 adds the substance.

The thing is, form is much easier to convey in a video than the substance.

When a building is rising in front of our eyes, it's very comprehensible to our brains. It's interesting to watch.  When some cables are added here and some boxes there, but nothing new is really growing in front of our eyes, it's not very fun to watch.

Anyway I did try my best to convey the substance in Part 2.

Part 2, showing the construction in October and November 2014, is here:

Part 1, showing the construction in August - September 2014, is here:

Enjoy watching and let me know if you have any comments or questions!

Our New To Do List

Our most pressing tasks include:

1. Digging a well

2. Building a chicken coop

3. Planting a hedge

4. Making wooden benches and a signboard

Each task is discussed in detail below.

Picture above:  Our plant in February 2015. Photo was taken by our friend Shinozaki-san with a very big and very good camera.

1. Digging a well

Without water, you can't grow plants or keep animals.

We have two options:

A. to dig a shallow (several meters deep) well ourselves

B. to have a deep (50+ meters) well dug by a professional

Digging a well ourselves would be much cheaper and we would get a hands-on experience of digging a well and installing a pump. The demerit is that the water would be of bad quality, given the pesticides used every year on the rice fields around. It would be okay for watering the plants but not for drinking.

Having a deep well dug would be much more expensive and we would get zero practical experience, but we would have clean drinking water.

Access to drinking water might be the single decisive factor - we're now leaning towards having a deep well dug.

2. Building a chicken coop

This is now in progress. It'll take  a few more weeks given our not-so-excellent carpenter skills and the fact that we can work mostly on weekends only.

Picture on the right: Nobu and me smiling to Shinozaki-san's camera. Thank you, Shinozaki-san, for taking great pictures!

3. Planting a hedge

This is in progress too. The first step is obviously to dig holes around the entire plot. I'm proud to say that hole digging has become my second nature. I've dug many holes of finest quality. If you need to dug a hole or two, ask me. I'm good at it.

The other day I planted ume - plum tree (blooming season is right now) and a sakura tree (to bloom in a few weeks). Sakura and ume are not hedge plants but will definitely add some beauty to the place.

This is plum (All photos below were taken by my iPhone. The difference from the photos above is obvious.):

This is plum with a cool I-don't-care-what-you-do-I'm-not-even-watching-you cat in the background:

This is the same plum in detail:

This is sakura tree:

Don't tell me you can't see it. It's right there. It's going to be a grand sakura tree in about half a century.

4. Building wooden benches and a signboard

Benches - we received a complaint from a visitor that there's no place to sit and rest. Very accurate observation indeed. We've added benches to our to do list.

A signboard - people walking around look bewildered, not knowing what's going on in here. Clearly, a signboard with minimum information about our solar sharing project is necessary. Ideally it will be made of wood and it will include our public Project Name (to be made up) and some curly ornaments in the corner.

I'll inform you about our progress in each area.

Generation & selling electricity started!

Some awesome news: On November 27, 2014 our solar power plant was connected to the grid and started generating and selling electricity. Finally.

Now the most important thing in the world is weather.

The weather on the ｇrid-connection day ( or "system interconnection" day?) was perfect blue sky but that was followed by a string of cloudy and rainy days, so we are yet to experience full capacity operation. Waiting for the next blue sky.

On the picture below is Tepco employee in the midst of grid connection procedures. I have no idea what he was doing and he didn't look like he wanted to be asked. Hence, no caption to the picture.

The next picture is the power plant shortly after it was connected to the grid and started generating electricity at around noon. (Yes, it does look the same as before,  but well...)

And here's the same place on the next day, November 28. With this darkness the amount of electricity produced is almost zero. Photons, you're welcome back any time! Soon!

I'm sure once we get used to it we'll stop talking about weather all the time. It's just now, so be patient with us.

Panel rotating mechanism: From lever to winch

（日本語）

Panel rotating mechanism allows us to easily change the angle (tilt)  of all 354 panels at once. The weight of 354 panels is more than 3 tons, so it's a big deal.

Until now we were able to move the panels with a lever, but that recently changed to a winch. So what's the difference between a lever and a winch? Winch is even easier to move - turning a winch requires very little physical strength. ...And winch somehow looks more sophisticated...

Watch this before-after video:

We had this panel rotating mechanism installed by our friend Matsuoka-san and his company SOLAR CULTURE.

"Oo" Schedule Update 3

（日本語）

Never mind it's long overdue: Here's our latest schedule update!

I posted the first project schedule in January 2014 and updated versions in March and August, so this is the third update in a row.

With such a long break,  it's now a report of past events rather than a schedule for future events.

In this latest, ehm, report, there are two major modifications to the previous schedule, one is bad and one is good.

Bad: The power plant is not finished yet.

According to the previous schedule, the power plant was supposed to be finished by now. What seemed like a small delay in August turned out to be a major wait. 

Good: The power plant will be finished soon.

The end is in sight! And it's close!! Finally it's not just wishful thinking but a concrete day in the calendar. Keep reading:

The single biggest news is that we finally got the quotation and the interconnection date from TEPCO.

Quotation means that TEPCO finally figured out and kindly let us know how much it'll cost us to have our power plant connected to public grid. (I'm not sure quotation is the right term in this context.)

Interconnection date means that TEPCO finally figured out and kindly let us know when they plan to connect our plant to the grid. That should be on November 27.  We've been waiting months for this.

Connection to the grid means that the plant will finally start generating electricity and income.

Here's the updated schedule:

For comparison, here's the previous schedule from August:

And for more comparison, here's the original schedule from January (some items and their timing was not quite right):