Martin: Living off the grid

My friend Martin is living off the grid. He covers all his electricity needs from a 100 watt solar panel. The panel generates, on average, 330 watt-hours of electricity a day.

For comparison, electricity consumption of my refrigerator is about 1000 Wh a day (calculated from the nameplate annual consumption 370 kWh. This was the first time I actually read the label).

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Martin does not have a fridge. Neither air conditioning nor television.

His electricity consumption can be roughly summed up as: using a laptop computer, using two LED lamps, using washing machine once a week, and an electric fan in summer.

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When Martin wants to charge his laptop, he doesn't plug it into electric outlets on the wall like the rest of us. Martin's electricity comes from a lead-acid battery, which stores electricity generated by the solar panel in the garden. The panel is outside just behind the window, attached to a bamboo stick and facing south.

That panel has been Martin's only source of electricity since he discontinued contract with Tokyo Electric Power Company a year and a half ago. He gets no electricity bills.

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In the first days of his solar power life, Martin was playing around and trying things out. For example how long could he use a microwave? Answer: not long. The battery was empty in 5 minutes. All electricity used up, he had to spend that evening in darkness.

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Needless to say, there is no microwave in Martin's place anymore. Just in case, he bought this emergency headlight↓on the picture for potential evening blackouts. But as Martin gradually got smarter in adjusting his energy usage to the available watt hours (more on sunny days and when the battery is fully charged, less on cloudy days), there's only very occasional need for the headlight.

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So is Martin an ascetic hermit or a radical hippie? Neither.

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Martin is a scientist by profession. He came to Japan from Germany as a doctoral student in 2010 to do research on photovoltaics. He completed his degree last year and is now working as a researcher in one of Tsukuba's institutes.

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I was at Martin's PhD thesis defense and I felt like Alice in Wonderland, lost in a parallel universe whose inhabitants were casually talking about "droplet epitaxy" and "coupling of quantum dots" in the pursuit of "developing strain free material systems for IBSC research." That's the wonderland behind future photovoltaic technology.

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Martin's private world is much more comprehensible to the laymen, and the room in Tsukuba he's renting, with tatami floor and the bamboo shelf and pumpkins at the front door, is very cozy place that people like to visit.

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Martin came to Japan in 2010. In March the following year, Great East Japan Earthquake accompanied with tsunami stroke the country, followed by Fukushima Daiichi nuclear reactors' meltdowns. This event literally changed the course of history in Japan.

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Tsukuba is 180 km south from Fukushima Daiichi plant. It's quite possible that if Martin came to Japan in different time, he wouldn't be living the life he is living now. Fukushima disaster impacted us more deeply than we're willing to admit.

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This was the first time that some people started to ask the question that is so rare in advanced economies:

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What is "enough"?

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Kondadai - forest in the city

(This article is not about solar sharing, but the topic is at least as important.)

Kondadai is a piece of forest about 4 km from Tsukuba station in the city of Tsukuba, Ibaraki prefecture.

Kondadai is one of few remaining patches of wild land in Tsukuba. Despite being surrounded by houses and fields, this small jungle has ecosystem rich enough to provide habitat to birds of prey. Hawks (ohtaka) and buzzards (sashiba) are both classified as "near threatened species" on the Red List of Japan's Ministry of Environment. Presence of endangered hawks has helped prevent development in the area so far, but future is uncertain.

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Besides rich natural environment, there are also cultural assets in Kondadai - ruins of Konda castle. They are very mysterious ruins though - buried under the grasses, you have to fully employ your imagination to spot them.

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Kondadai is now protected thanks to the efforts of Kayoko Takahashi and her Association for the protection of Kondadai ecosystem 金田台の生態系を守る会. On Sunday Nov. 10, 2013, I took part in a study walk through the forest, regularly organized by the Association.

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Kondadai is, in a way, a classic story of conflict between two forces: nature conservation versus urban development. In the story, developers are blamed for insensitive destruction of nature in the name of progress, and environmentalists are blamed for hindering development by uselessly trying to protect every tree and bird.

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But when I was walking through the Kondadai forest on Sunday, I was thinking of it as neither The Environmentalist nor The Developer. Instead, I tried to look at Kondadai through the lens of a local resident.

Nishigoya Opening ceremony 2013/10/27

Nishigoya Solar Power Plant of Ken Matsuoka began operation on October 15, 2013. The opening ceremony was held soon after - on Sunday October 27.

It was the sunniest Sunday you could wish for an event at a solar power plant.

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Matsuoka started his address with self-introduction: "I'm Ken Matsuoka, chief of Nishigoya Solar Power Plant."

He laughed and the audience too. "Power plant chief" was an exact description of his role in the project, and yet the words somehow sounded too big. Not many people can introduce themselves as power plant chiefs. Not many people know someone who'd be a power plant chief. I was proud to be one of them.

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Among the guests there were family members and friends who volunteered their time to help build the plant, and also some VIPs - like the father of solar sharing Akira Nagashima and Japan's ex-prime minister Naoto Kan.

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Here at the ceremony I heard for the first time the story of how it all began a year and a half ago:

By a series of coincidences, Ken Matsuoka happened to visit the Naoto Kan's office as a technical support for an interview. During the interview, Mr. Kan showed them materials on his desk: "Look at these amazing renewable energy projects."

On the desk, Matsuoka saw a photo of solar sharing. "I just found what I want to do," he allegedly murmured.

Next day he contacted Akira Nagashima.

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About the plant:

Matsuoka's plant consists of 579 panels (100W/panel) installed on a metal frame at the height 3.5 meters over an area of about 1500 m2. The plant's capacity  - maximum output to sell to electric utility - is 49.9 kW.

A special feature of Matsuoka's plant is a winch allowing to change the tilt of all 579 panels (more than 8 tons) at once. The device, according to Matsuoka, didn't cost more than 1 % of the total investment, but it could increase the output by about 5 % - that is a significant number over 20 years.

We could see the effect of the winch at the ceremony.

The Inventor

On October 23, 2013, I met Akira Nagashima at his Solar Sharing Trial Site (ソーラーシェアリング実証試験場)　in Chiba prefecture.

Akira Nagashima, the inventor of solar sharing, is a celebrity in the community of solar sharing enthusiasts.

There are two plants on his trial site, both connected to public grid. Each has an output of about 4.5 kilowatts. There are many solar sharing projects in Japan, but this site is special because it's the first one. All others are imitations of this one.

Plant No. 1 (一号機) is installed above the garden. On the picture you can see peanuts, carrot, leek, taro and a row of unindentified leaves growing under the panels. Nagashima is standing on the side.

Plant No. 2 （2号機） is installed above a parking lot. Nagashima is standing below with a customized module that just arrived from manufacturer.

It still feels strange to call this kind of solar installation a power plant. For too long time we used to think of power plants as big unsightly buildings somewhere faraway.

Definition: Power plant is a complex of structures and equipment for generating electric energy from another source of energy.

Solar panels on the pictures above generate electricity from sun - they are legitimate power plants.

Monstrous appearance we expect from power plants is, luckily, optional. Solar sharing plants so far unticked this option - they're neither big nor ugly nor remote.

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Eureka moment

The idea of solar sharing first popped up in Nagashima's mind 10 years ago - in late 2003. Nagashima, now 70, was then studying law at Keio University in Tokyo (yes, at the age of 60). Nagashima got a biology textbook in his law course.

Why would one need a biology book in a law course?

Good question. I forgot to ask.

In that biology book, Nagashima came across the concept of light saturation point.

Light saturation point: Plants need sun to perform photosynthesis. We tend to believe that the more sunshine plants get the better, but this is not true for most plants. The reason is that most plants have a light saturation point - the amount of light intensity beyond which photosynthesis rate doesn't increase. All light beyond this saturation point is not only useless, but can even be stressful to the plant (for example causing overheating and water evaporation)

The concept of light saturation point led to Nagashima's eureka moment: If plants don't need all sunshine they're getting, why don't we use the excessive rays for power generation? Instead of laying solar moduls directly on the ground, we can put them a few meters higher and with spaces in between, so that plants below can still get their share of sun and keep growing.

The idea was out there and the time was ready for the next step: work out details and give it a real, tangible shape.

And a name.

Solar Sharing Trial Site was established in May 2010. Plant No. 1 started operation in August 2010 and plant No. 2 in April 2011. This was the only solar sharing project in Japan at that time.

Fukushima nuclear meltdowns occurred in March 2011. This event was an involuntary turning point in Japan' way of thinking about electricity. Suddenly everyone (okay, many people) were willing to turn off air-conditioning for a while and got interested in renewables. Japan's energy policy changed. The change involved introduction of renewable energy feed-in tariff system, making it mandatory for electric power companies to buy electricity from renewable sources for fixed (and quite high) prices.

Solar sharing, while not yet known among general public, went under the spotlight. Today there are tens of projects all over Japan, and visitors come for study tours to Nagashima's trial site every week.

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