Download - Joint FP5 ENERGIE Info-day and EnerBuild RTD Project Meeting JAPANESE BUILDING ENERGY RESEACH
Joint FP5 ENERGIE Info-day and EnerBuild RTD Project Meeting JAPANESE BUILDING ENER
GY RESEACH7 September 2001, Malmo
Ken-ichi KimuraProfessor, Advanced Research Institute fo
r Science and Engineering,
Waseda University, Tokyo
Fax:+81-3-3209-8316
E-mail: [email protected]
Climate of Japan
• Japanese archipelago ranges from cold to subtropical regions.
• In central mild areas, heating season: November-April in residential buildings January-March in office buildings.
Energy Use Trends in JapanIndustrial Sector Residential and
Commercial SectorTransportation Sector
0
2000
4000
6000
8000
10000
12000
14000
16000
73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98
[PJ]
- S. Ando
Residential Energy Breakdowns by District
1/3 of CO2 are related to buildings in Japan
Operation Energy of an Office Building
Energy Conservation and
Natural Energy Utilisationare different.
Definition of Energy Conservation
• Minimisation of Energy Use while maintaining desire of people.
• Energy may be used as much as they want unless they think it wasteful.
• Energy conservation is not enough to meet the target of Kyoto protocol.
Natural Energy Utilisation
• Solar thermal• Photovoltaics• Wind power• Geothermal power• Ambient energy
Solar Hot Water Heaters
• Solar water heaters are installed in about 1/10 of total households.
• Forced circulation type of domestic solar water heating system can be seen in houses.
Solar Hot Water System
• Swimming pools
• Elderly people’s homes
• Hospitals
• Schools
• Apartments
Passive Solar Space Heating
• Traditionally common in residences.
• Insulation and air-tightness are prerequisites for passive solar heating
Passive Cooling in Residences
• Natural ventilation and sun shading are pre-requisites.
• Nocturnal ventilation• Cool tube• Earth contact floor• Roof garden for
evaporative cooling• Nocturnal radiation
Improvement in Efficiency of Household Appliances
• Refrigerators• Lighting bulbs
(Compact lamps are not common in Japan.)
• Room Air-Conditioners
Colour TV
Air Conditioner
Refrigerator
Year
Energy Conservation in Buildings
• Energy Conscious Designs
• Energy Reduction in Lighting
• Energy Reduction in HVAC
• Energy Reduction in Office Machines
Energy Conservation in HVAC
• Heat Recovery System
• Variable Air/Water Volume System
• Free Cooling/ Night Purge
• Sun Shading
• Air Flow Windows
• Controls for Efficient Operation
• Set Point Temperature and Humidity
Thermal Comfort and Energy Conservation
• 1 degree of change in set point temperature makes 10% of energy saving in both heating and cooling.
• Slight increase in air movement substantially reduces cooling load.
Indoor Air Quality and Energy Conservation
• Displacement ventilation
• Occupied zone air conditioning
• Minimum allowable rate of ventilation
Occupied Zone Air Conditioning in Large Spaces
0
500
1000
1500
Hea
t L
oad
[W
/㎡・
day]
MeasurementOccupied zone Air-ConditionOverall Air-Conditioning
8/18 8/208/19 8/23 8/24 2/16 2/18 2/19 2/21 2/22
Direct Sunlight Introduction
Photovoltaics Integration in Architecture
Residential PhotovoltaicSystem Installation
NumberCapacity
[MW]
PowerGeneration
[106kWh]
PowerRequired
[106kWh]
PVContribution
[%]
60,000 219 230 897,600 0.026
1,370,000 5,000 5,256 1,056,000 0.500
Residential Photovolaic Cost
2000 Aug. 2002 Forcast
PV module cost 56.0 (63%) 41.4 (64%)Ancilary equipment cost 20.9 (24%) 12.2 (19%)Installation cost 11.9 (13%) 11.2 (17%)Total system cost 88.8(100%) 64.8(100%)
PV Panels Backed with Air Collector
Kyocera House
Natural Energy Utilisation in Vernacular Architecture
Massive House in Kawagoe
Modern Use of Vernacular Technologies
Earth Covered Building
Solar Architecture
• Heavy insulation and air-tightness
• natural ventilation and sun shading
• passive solar heating
• solar domestic hot water system
• PV for appliances
IEA Task 13 AdvancedJapanese House-WISH House
Kimura Solar House - 1972
• Movable collector panels
• Semi-basement with greenhouse
• Floor heating by heat pump
• Solar domestic hot water
• PV roof (2001)
Sagara Solar House - 1979
• Hybrid solar• Outside
insulation• No auxiliary for
space heating• 5028 kWh/a for
total household
TEPCO Solar House - 1988• Earth contact floor• Rock bed storage coupled
with air collector and heat pump
• Sun space• Heat pump for hot water
from space cooling with off-peak electricity
• Phase change material floor• 7800kWh/a for total
household
Solar Chimney and PV Panels
• School building of Kitakyushu University, Faculty of Environmental Engineering
Carbon Emission from Buildings by Structural Types
-100
-50
0
50
100
150
200
WOODEN STEELREINFORCEDCONCRETE
REINFORCEDCONCRETE
STEEL AVERAGE
CA
RB
ON
EM
ISS
ION
PR
OM
BU
ILD
ING
SF
OR
FLO
OR
AR
EA
[kg
/m2]
WOOD(-)
OTHER MATERIALS
TRANSPORTATION
STEEL
CERAMICS
CONCRETE
WOOD(+)
Global Environment Committee,AIJ 1992
Conclusion-1
• Energy conservation has a largest potential in reducing energy requirements in building sector.
• Different types of natural energy utilisation must be sought for different conditions.
Conclusion-2
• A slight discomfort must be accepted for reducing energy use and warming gas emission.
• It can be regarded possible to meet the target level of Kyoto protocol as far as building sector is concerned in Japan.