collaEb.
eco + collaboration + laboratory

Graduate School of Environmental Studies Tohoku University

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OutlineElevation view

Ecollab. and its Architecture

Noriyoshi Tsuchiya
Professor, Chair, Building Committee,
Graduate School of Environmental Studies, Tohoku University
While our graduate school has diverse research fields

cut from the cedar forest of the Field Science Center,in different campuses and the main school building has

Graduate School of Agricultural Science and the same

to be multi-functioned for administrative purposes, thelocal area in northern Miyagi. Using cedar lumber fromenvironment of our school campus was not optimal.

the field science center was also an eco-friendly idea

To remedy this state, a new building plan was drawn

since the trees were originally scheduled to be thinned.

up in the summer of 2007. With the aim of providing

I really wish that this nature -friendly architecture

a symbolic and novel building which stands for“Ecollab.”, built by the Graduate School ofenvironmental science, our project for the new school

Environmental Studies, becomes a center forbuilding started.

new creativity and encourages us to redefine our

On November 22, 2007, we held a competition

relationship with nature.

for architectural design proposals. Based on the

To accomplish the project, we had great support fromselected basic design plan, the preliminary design

successive Deans (Shoji Taniguchi and Kazuyuki Tohji),

was completed in the same fiscal year, and thethe Deputy Chair of the Building Board (Koji Ioku), all

implementing design was finished by the springcommittee members and staff of the graduate school.

of 2009. Construction began in the same summer

Furthermore, we also received much assistance fromfollowing approval from Sendai city, and the facility was

staff of the School of Engineering. The project would notcompleted by the end of the fiscal year.

have been accomplished without the dedicated support“Ecollab.” is a facility that employs specific materials

from staff members. We would like to express ourand techniques and secures flexibility for change of use

gratitude to all of those involved in the Graduate Schoolin the building. Also, for the purpose of supporting local

of Agricultural Science, as well as those involved for

production and local consumption, we used solid woodbuilding Ecollab.

1.Basic Concept for Designing
Ecollab. was designed not only as a symbolic researchfacility of the Graduate School of Environmental Studies
but also as a modern, simple yet airy space withflexibility for advanced research experiments. Also,
functionalities such as insulation and air-tightness wereconsidered while the wooden architecture’s strength warmth and softness were encouraged.
2.Space Concept
The basic concept is “open space for inside andoutside of the school”: not just for researchers andstudents but also for local citizens.
(1) Exterior space: gently connected to interior space
・1F: Provides expansive atmosphere with open glass
sides in the south and east-west.
・2F: Creates an image of floating grid screen on thegrass and soft atmosphere.
・PH: Skylight windows for both lighting and ventilation
glow like a huge symbolic lantern after dark.

with a feeling of both tension and calmness.
3.Environmentally-focused Design
Good view and open space(1) Natural ventilation: using the open ceiling space(a path for the wind) from the entrance hall tothe skylight windows, convection generated by
the temperature difference between outside andinside goes up and down, and by this process
it automatically activates wind-power ventilation.
In summer, not much electric power is needed
because the system lets the indoor heat go up
through automatic ventilation windows on the
skylight. In winter on the other hand, the air-swing
fan on the skylight blows warm air down to the firstfloor to warm up the entrance hall.
Natural ventilation in open ceiling space

Elevation view
Elevation view
Summer time(2) Interior space: changes the image of an exclusive
research facility into inclusive laboratories
with open ceiling and glass sides, overlooks
horizontally and vertically enough to let you feel thepresence of residents.
Good view and open space

Good view and open space(3) Design that features the nature of tree structure:asimple way of using structural members of beamand roofing boards features the nature of tree
Naturalventilationin open ceilingspace
structure- fiberand softness– andcreates space
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OutlineNatural ventilation in open ceiling space

Winter time(2) Lighting: thanks to the daylight from the skylightwindows, there is little need to use artificial lightin the entrance hall during the daytime. Also, theuse of latest highly-efficient lighting (LED) makes it
possible to reduce the electricity consumption.
(3) Humidity control: to make the most of the humidity
control function that wood has, walls and ceilings
were furnished by cedar wood. Furthermore, tomaintain the stable indoor environment, the walls
are made using material that naturally controls
humidity.
(4) Local production for local consumption: making
an effective use of local resources such as tree
thinning supports the maintenance of mountains
and forests. The design plan of construction,framework, and finishing of the facility was to use
local materials such as thinned cedar trees in the
Kawatabi farm operated by the Graduate Schoolof Agricultural Science, Tohoku University, andlocal builders and carpenters. To support the local
economy, a traditional wood framing techniquethat is familiar to local artisans was adopted.

Ecollab. and its Architecture2

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How to Build Ecollab.

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1.Mountains in Kawatabi area, where the cedar
trees were born.
2,3.Winter season is the best for logging whentrees go dormant.
4.4 0~80-year-old trees were selected for
logging.
5.After logging, wood and leaves dried.
6.Logs delimbed and cross-cut by a processor.
7.Logs piled up on the ground.

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15.At the processing factory for curving.
16.S cheme of Japanese traditional woodframing technique. The technique for jointing
without using any metals.
17-21.P rocessing done one by one by handworking. Traditional technique supports
advanced technology for Ecollab.

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8.Barking process by a ring barker.
9,10.Sawing logs after barking.
11.Beam end finishing.
12.After sawing, lumber seasoned in the smoke
house.
13,14.Seasoned lumber carried out.

22.Base completed.
23.Join technique for doubled beam.
24.D ouble beamed technique and batter braceframing strengthen the building.
25.On January 12, 2010.
26.Steel-frame stairs installed.
27.On March 17, 2010, construction completedsoon.
28.Completed.

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How to Build Ecollab.

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Quick charge/discharge performance
Can charge over 90% in 1hour

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Low environmental impact

Solar panels

Uses iron instead of rare metal for electrodes

Conventional power feeding to DC device
DC
Conversion loss AC Conversion loss

Quick
Long
life charge/discharge performance

Technology in Ecollab.

Power conditioner

DC

AC/DC Converter

AC

Conversion loss

OutputConversion loss

DC

Expected
to lastcharge/dischargeforat 90%
least 10years
Can charge
overin 1hourQuickperformance
HighLow
safetyCan charge over
90% in 1hour
environmental
impactSolar panels

Power conditioner

AC/DC Converte

Excellentheatinstead
stabilityof rare impact
environmental
Uses Lowiron
metal for electrodes

Solar panels Power conditioner AC/DC Converter
Conventional power feeding to DC devic
Storage battery system DC/DC converter
OutputSolarpanelsLong lifeUses iron instead of rare metal for electrodes
Conventional power feeding to DC device
DC
Long life
Ecollab. power feeding to DC device
Expected to last for at least 10 years
DC
Expected to last for at least 10 years

High safety

High safety

It has been considered that the power system at home has to run on AC (alternating current). Meanwhile, hardware

From electric power selling to captive
consumption

nowadays has both high functionality and energy saving thanks to computerized control and digitalization. Thismeans that the power has been supplied by AC and used as DC (direct current). So if the power is supplied byalso has an extreme loss for the DC/AC conversion to reverse the power flow to the power line. It is thus time for aperceptional change to provide power by DC for buildings of the low carbon society. The Lithium-ion secondary
battery is a key device. If we install the storage battery, it is possible to build a solar power system and even use
small and weak energy that has hitherto been disposed of without being used.
The energy system of Ecollab. was established based on these ideas, and a new concept introduced to rebuild
the power system in the house and to aim for energy saving and drastic CO2 reduction in the civilian sector. Ecollab.
installs solar panels of 5.8kW and 10kW of lithium-ion storage batteries and is a demonstration experiment.

DC
Quick charge/discharge performance
Low environmental impact

Solar panels

Uses iron instead of rare metal for electrodes

Stable power supply when generated
Conventional power feeding to DC device
power fluctuates

Long life

Excellent heat stability

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DCConversion loss

AC

Conversion loss

AC/DC Converter

OutputEcollab.

Ecollab.

Supplement

Changes due to climate

Nightly drop in generated power

Required power

PV 46W×54 panels

Solar power
DaytimeDC voltage

Evening Night Morning

Daytime
EcoMinohru®

Evening Night Morning

Solar power

converter
compositor

AC/DC

PV 46W×54 panels

DC

DC24V

Supplement

DC24V

DC300V

AC200V

Solar panels
Solar panels

Power conditioner

Commercial power

Conventional
system Output
Power conditioner
AC/DC Converter

Conventional power feeding to DC device
DC
DC/AC inverter
Solar power
Solar panels Storage battery system DC/DC converter
Ecollab.
Ecollab. power feeding to DC device

Technology in Ecollab.

Storage battery
OutputChanges due to climate
Sunlight

DC/DC converte

DC/DC converter

Solar power
Sunlight
Changes due to climate
Nightly drop in generated power
Generated powerDC
Daytime
Evening Night Morning
Sunlightpower
Required
When the weather turns bad andGenerated power
Supplement

not enough solar power is generated
for consumption, the deficit will besystem DC/DC by
OutputSolar panels Storage battery
converter
supplemented
the storage
battery
to stabilize the power supply. Power
Ecollab. power feeding to DC device
supply from lithium-ion storage batteries
is also possible for a certain amount oftime at night or during power failure.

Excellent heat stability

DC power feeding allows 0 conversion loss
Thinking about the conventional solar power
generation system, DC power is generated by thephotovoltaic system Quickand charge/discharge
generally theperformance
power isconverted to AC for use.
for overdigital
CanButcharge90%devices
in 1hour suchas laptop computer and liquid crystal display TVs
Low environmental impact
which are operated on DC, the power has to beUses ACiron insteadrare metalelectrodes
converted once again fromto DCofbefore
it forcanbeLong life
used. For each conversion
there is a conversion lossof 10%. Since more andExpected
more appliances
run10onDC
to last for at least
years
nowadays, this loss cannot be ignored anymore.
High safety

Power conditioner

Expected to last for at least 10 years
High safety

Solar panels Storage battery system
Solar panels Storage battery system

Required power

Can charge over 90% in 1hour

The Lithium-ion battery has no self-discharge buthigh charging performance. It also does not reduce
its capacity in recharging even though there is someremaining, and can take in even just small amounts ofpower. With this feature, Ecollab. uses the secondary
batteries not only for power backups but also for takein and for a stable supply of renewable energy whichis unstable and weak at its source.

Excellent heat stability

Ecollab.
toDC
DCdevice
deviceEcollab.power
power feeding
feeding to
Solar panels
Power conditioner
Commercial power
Captive consumption is difficult toimplement with the conventional method
Conventional systemof solar power generation system used
Consumed powerfor power selling, because the systemneeds a power conditioner. Also, solar
power output fluctuates in a way that
DC/AC inverter
Solar panels
Power conditioner
Commercial powerthat might compromise the quality
Solar panelsPowerconditioner
Commercial
power
of commercial power when selling.
Conventional
systemSolar power
Storage battery
DC/AC converter
Conventional
system
By installing the storage batteries
Ecollab.
Consumed powerat Ecollab., there is no need for a
Consumed power
conditioner and this allows us to use
power independently of the commercial
DC/AC inverter
Changes due to climate
Nightly drop in generated
power
power.
InsteadDC/AC inverter
Conversion
loss AC
ConversionoflosssellingDCpower, weSunlight
manage to use renewable energy all
DC/AC converter
Solar power
Storage battery
Generated power
generated in the building.
Solar power
Storage battery
DC/AC converter

DC, we can unconsciously and easily reduce the power loss (10%) on AC/DC conversion. Solar power generation

Olivine-type iron phosphate lithium-ion secondary
battery

Excellent heat stability

DC/AC converter

DC power supply to appliances
To cut the power conversion loss in
Ecollab., DC power which is generated
power system is directlyin theConsumed
solar power
provided to some of the lighting andair conditioners. The result of an AC
operation test shows that an average
62% of consumed power for a day is
generated in the solar power system.

Nightly drop in generated powerAC

PV 46W×54 panels

AC/DC

DC

DC24V

DC voltage
converter
compositor

EcoMinohru®
AC200V

AC/DC

DC voltage
converter
compositor

EcoMinohru®
AC200V

DC300V
AC

DC

DC300VAC

DC

Technology in Ecollab.

65Energy Saving Lifestyle

To transition to a low carbon lifestyle without lowering

one close to the user. This can enhance the power

our quality of life, it is necessary to introduce high-saving effect and make a more comfortable living

tech energy control based on DC power feeding, andenvironment.

to smoothly add “use of natural energy,” “reduction of

The straight-line DC table which can be called awaste,” and “saving every small energy” into a daily“modern fireplace” has the functions of bathroom,

rhythm. To make this possible, one of the models in the

kitchen, dining, study, and living room. In the DC Life

house is the “DC Life Space”.

Space, power feeding points are all consolidated in

The DC Life Space consists of four elements; athe DC table. Having a table as a “charging station” in“DC table” which has provided the basic supply

the house makes charging much easier to introduce ininfrastructure of DC power feeding and plumbing in thedaily life. When wireless charging system technology is

kitchen, “rise-and-fall floor” which allows you to rest,

realized, it will become easier to store power generated

eat, work depending on height and distance from theby bicycle.

DC table, “LED lighting” that runs on DC power and can

By designing the details of relationships between

be operated by computer or information equipment,

objects around us and energy, we made a spaceand “curtains” that softly separate the space in thewhich does not separate your activity by wall or room

layers of lighting and natural lights.

but naturally connects your daily life as a sequence ofLED lighting which can control and keep a comfortableactions. We hope you will be able to see the lifestylebrightness in response to human activities can providethat gently connects living a life and generating energy.

sufficient lighting by combining its base light and the

PH

PH

PH

外部仕上表

Exterior finish schedule
Roof
Roof -1 (Z2)Roof -2 (ZR1)
Roof -3(ZR2)
Roof -4 (ZR1)
Roof -5 (ZR1)

2F

Exterior wall
Exterior wall – 1
Exterior wall – 2
ScreenFittings

FL steel t = 0.4 Sealing
FL steel t = 0.4 Sealing
FL steel t = 0.4 Resin welding
FL steel t = 0.4 Sealing
FL steel t = 0.4 Ribbed seam roofing

US cedar panels t ＝ 18 (non-combustible)
Galvalume steel t ＝ 0.4 spandrel
Wooden louver (US cedar)
Aluminum, wooden + protective coating, steel + FUE

2F

FL steel t = 0.4 Sealing
FL steel t = 0.4 Sealing
FL steel t = 0.4 Resin welding
FL steel t = 0.4 Sealing
FL steel t = 0.4 Ribbed seam roofing

Exterior wall
Exterior wall – 1
Exterior wall – 2
ScreenFittings

US cedar panels t ＝ 18 (non-combustible)
Galvalume steel t ＝ 0.4 spandrel
Wooden louver (US cedar)
Aluminum, wooden + protective coating, steel + FUE

1F

根

屋根 -1（Z2）

FL 鋼板 t ＝ 0.4 W 融着工法

屋根 -2（ZR1）

FL 鋼板 t ＝ 0.4 W 融着工法

屋根 -3（ZR2） FL 鋼板 t ＝ 0.4 樹脂溶接工法（ハゼ @500）
屋根 -4（ZR1）

FL 鋼板 t ＝ 0.4 W 融着工法

屋根 -5（ZR1）

FL 鋼板 t ＝ 0.4 瓦棒葺き

外

2F

壁

外壁 -1

米杉張り t ＝ 18（不燃材）

外壁 -2

G 鋼板 t ＝ 0.4 スパンドレル

スクリーン

木製ルーバー（米杉）建

アルミニウム製、木製＋木材保護塗料、鋼製＋ FUE

具建築概要
棟 名 称 ： 研究棟（エコハウス）
工
種 ： 新営
構 造・ 階 数 ： 木造 2 階（塔屋 1 階）
建 築 面 積 ： 669.22 m2
延 べ 面 積 ： 997.55 m2
1 階 床 面 積 ： 516.00 m2
2 階 床 面 積 ： 450.85 m2
PH 床 面 積 ： 30.70 m2

Building name : Research building (Ecollab.)
Construction type : Operate a new construction
Structure : Two-story wooden building (one story penthouse)
Building area : 669.22 m2
Gross floor area : 997.55 m2
First floor area : 516.00 m2
Second floor area : 450.85 m2
PH floor area : 30.70 m2

Building name : Research building (Ecollab.)
Construction type : Operate a new construction
Structure : Two-story wooden building (one story penthouse)
Building area : 669.22 m2
Gross floor area : 997.55 m2
First floor area : 516.00 m2
Second floor area : 450.85 m2
PH floor area : 30.70 m2

1F

Roof
Roof -1 (Z2)Roof -2 (ZR1)
Roof -3(ZR2)
Roof -4 (ZR1)
Roof -5 (ZR1)

General Information

General Information

7屋

Exterior finish schedule

1F

Energy Saving Lifestyle

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Disaster and Ecollab.

On March 11, 2011, an unprecedented earthquake
struck Eastern Japan. Power was lost, snow fell, and we
all spent an uncomfortable night in the darkness. This iswhen Ecollab. showed its stand-alone power function.
After the earthquake, university students and staff who
were unable to return home gathered at Ecollab. andturned on lights running on rechargeable batteries,
charged cell phones, and had dinner together.The
charge and discharge system, solar panels andbatteries were then delivered to a disaster area in
Ishinomaki, and supplied electricity to the area where
the public power supply was not recovered for over amonth.
Following the disaster, we realized the importanceof stand-alone power in the home, and Ecollab. iscontinuing to improve its functions as it pushes forwardwith the important mission of creating disaster-proof
houses and communities.

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To be a Local Energy Center

By learning from the experience of the earthquake
disaster, we contribute to creating a safe and reliablecommunity that will never run out of energy, with theuse of renewable energy as the public power sourcein both emergency and normal conditions. To make itpossible, we installed power feeding ports and a multipurpose power feeding station in the Ecollab. yard
after the disaster. Solar power energy is supplied to theequipment through the storage battery, and the power
is provided for free to anyone to recharge devices. At
the multipurpose power feeding station, an electronic
vehicle (EV) is used for power transfer and backup
independent of commercial power. If we use the EV as

Power feeding port

＊ This research is based on the project “Nextgeneration Energies for Tohoku Recovery” and isfunded by the Ministry of Education, Culture, Sports,
Science and Technology.

Multi-purpose power feeding station

PV 46W×18 panels

In Ecollab. DC Life Space, in the night of the earthquake on March
11. Staff and students having dinner under the light powered bystorage systema “mobile storage battery” which transfers power fromthe power feeding station, it is possible to broaden the
supplying area beyond just the inside of Ecollab. The
Graduate School of Environmental Studies has b¬een
working on this kind of project to introduce a power
feeding system using natural energy and establish “local
energy centers”.

PV 46W×9 panels

Port

Port

AC/DC
USB outlet
Night light

AC100V

AC/DC

Wireless charging outlet
DC outlet for PC
USB outlet
Night light

AC100V

Storage battery
AC

Solar panels, installed at an evacuation shelter (Ozashi,

A light, turned on at Ishinomaki Watanoha Junior High School for

Jyusanhama, Kitakami, Ishinomaki)

the first time after the disaster

Professor Tohji setting up charge and discharge system

Associate Professor Hirano checking charge and discharge

DC

DC48V 20A

Storage battery Electric vehicle

Lights at Christmas using DC from batteriessystem at an evacuation shelter (Aikawa, Kitakami, Ishinomaki)

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Disaster and Ecollab.

To be a Local Energy Center

1010Graduate School of Environmantal Studies
Tohoku University
6-6-20 Aramaki-aza-Aoba, Aoba-ku, Sendai
980-8579
TEL：022-795-7414 FAX：022-795-4309
http://www.kankyo.tohoku.ac.jp