Qinhuangdao has developed a flagship
demonstration Passive House project ‘Zai Shui Yi Fang’ as a part of
International Cooperation Project (Sino-German Project) under the auspices of
Scientific Development Promotion Centre of the Ministry of Housing and
Urban-rural Development, China and German Energy Agency (DENA). A total of 4 high-rise
residential buildings, each with18 floors high, are being built in the Qinhuangdao
‘C’ block in two phases. It covers a total construction area of 80,344 square
metres and is expected to be completed by November 2013. The building falls in
temperate climate with a long heating period and short cooling period.
Overall performance
The
project has set the stringent target of the German Passive House standard in
contrast to conventional less stringent domestic standards for residential
buildings in China. The building has set out to construct an exemplary building
envelope and integrate it with efficient thermal comfort systems. The new
building is expected to bring heating demand down by 75% compared to
conventional energy efficient.
Cost and effectiveness
The overall costs amounted to € 296/m2 which is approximately 10.5% premium over the cost of constructing conventional efficient buildings. However, area saved due to the implementation of innovative energy systems and minimized service areas led to more saleable space and thus offered a bargain for the extra premium. In addition, heating subsidy offered by local finance scheme and recurring reduced energy bills offer an attractive pay back period for the capital. The passive house is expected to save heating energy costs of approximately € 56,481 per annum.
Building basics
Year of completion |
2012 |
Number of units |
54 |
Number of occupants |
150 people |
Elevation |
10 m |
Building areas
Residential space |
5112 m2 |
The demonstration project is a high rise housing with three dwelling units on each floor. Each dwelling unit is 177 m2 in area and consists of bedrooms, baths, kitchen, dining and a balcony.
Special features
Solar powered street lights, Solar PV installation for basement lighting, waste water reuse capacity of 200 m3 and rain water harvesting facility.
The
external wall is made of concrete and it is heavily insulated on the outside with
a double layer of expanded polystyrene (EPS) board to ensure Passive House
standards for walls which is less than 0.15 W/(m2K). All the layers are joined together by using
full scraping adhesive mortar and anti-cracking nets. The outer layer is made
using a set of weatherproof membranes. A thick fire resistant rock wool
insulation has been added above the lintel. The parapet of the balcony is
insulated as well, with a 270 mm thick insulation. Interior walls that separate
dwelling units are insulated using 30 mm thick polyurethane board.
All
above grade building floors except the ground floor above the basement are made
up of concrete slabs are insulated using 30 mm thick polystyrene board
insulation with an additional sound barrier. The ground floor above the basement
is insulated using 160 mm thick B-1 grade polystyrene board insulation. Foam
glass insulation has been used to insulate basement walls.
Double
glazed windows with vacuum trap and UPVC frame have been used. All the doors
that open to exteriors/unconditioned hallways are specially sealed for air
tightness. The U-value of windows and doors is between 0.8-1.0 W/(m2K).
Thermal bridges are avoided by special details at all critical junctions such
as the installation of outdoor unit for air-conditioning, vent and plumbing
pipes. All the refrigerant pipes are specially insulated and are housed within
the insulated building envelope.
A
certified blower door test has been conducted to measure the air tightness of
the house, to seal any potential
leakages and to meet passive house standard of 0.6/h at n50 value.
Type of construction |
Heavy |
A/V ratio |
0.25 -1 |
Thermal bridging |
Detailing for thermal bridge free design was carried out according to Passivhaus criteria. |
Air tightness |
Certified pressure test (blower door) |
Air tightness value |
0.40 1/h |
Shading |
Internal blinds |
Ground floor
U-value |
0.150 W/m2K |
Total thickness |
44.00 cm |
Total area |
343 m2 |
Material |
Thickness |
Thermal conductivity λ |
Screet and finish |
6.00 cm |
0.930 W/mK |
Plaster coat |
2.00 cm |
0.930 W/mK |
EPS insulation exterior |
16.00 cm |
0.042 W/mK |
Concrete slab |
10.00 cm |
1.740 W/mK |
EPS insulation interior |
10.00 cm |
0.042 W/mK |
(From outside to inside)
External walls
U-value |
0.150 W/m2K |
Total thickness |
61.00 cm |
Total area |
3620 m2 |
Material |
Thickness |
Thermal conductivity λ |
Plaster coat |
1.00 cm |
0.930 W/mK |
EPS insulation board |
22.00 cm |
0.042 W/mK |
Concrete wall |
18.00 cm |
1.740 W/mK |
Cement plaster |
20.00 cm |
0.930 W/mK |
(From outside to inside)
Upper ceiling
From outside to inside.
U-value |
0.110 W/m2K |
Total thickness |
44.00 cm |
Total area |
357 m2 |
Material |
Thickness |
Thermal conductivity λ |
Cement plaster |
2.00 cm |
0.930 W/mK |
Concrete slab |
10.00 cm |
1.740 W/mK |
Self levelling |
2.00 cm |
0.830 W/mK |
EPS insulation |
27.00 cm |
0.042 W/mK |
Waterproofing-slope |
3.00 cm |
0.180 W/mK |
(From outside to inside)
Windows
U-value window |
0.90 W/m2K |
Total area |
1040 m2 |
Glass infill |
Argon |
Coating/Tint |
Low-E |
Solar heat gain coefficient |
0.30 |
U-value glass |
0.70 W/m2K |
U-value window frame |
None W/m2K |
Passive strategies
Each house is centrally air-conditioned using a split ducted reversible VRV system with 75 % efficient heat recovery capability. The conditioned air is distributed from the central air conditioning unit to various rooms using ducts and the return air is collected from a single point. The air-conditioning system also supplies the required fresh air into the house.
Indoor design temperature summer |
26 °C |
Indoor design temperature winter |
20 °C |
Heating system
The heating capacity is 3.3 kW with an input power requirement of 1 kW. The COP of the complete machine is 2.8 and is expected to perform at a COP of 2.4 when the ambient temperature is -10 °C.
1 individual heating system installed:
Type |
Heat pump (air) |
Heating capacity |
149.00 |
Annual final energy consumption |
14742 |
Centralised/decentralised |
Decentralized |
Thermal efficiency |
2.730 |
Energy source |
Electricity |
Distribution system |
Air |
Cooling system
The cooing capacity of the system is 2.7 kW with an input power requirement of 1 kW. In addition, the heat rejected during the cooling period is used in the production of domestic hot water with a tank capacity of 150 L.
1 individual cooling system installed:
Type |
Electric Chiller |
Cooling capacity |
159.30 kWth |
Annual final energy consumption |
33621 kWh/year |
Centralised/decentralised |
Decentralized |
Coefficient of Performance (COP) |
2.75 |
Energy source |
Electricity |
Distribution system |
Air |
Hot water system
1 individual hot water system installed:
Centralised/decentralised |
Decentralized |
Solar thermal collector |
vacuum |
Aperture size |
2.0 |
Contribution to heating |
60 |
Energy source |
Solar |
Ventilation system
The fan power is 90 W. The return air from the system is directed towards the outdoor unit, which helps to keep up the efficiency of the outdoor unit.
1 individual ventilation system installed:
Centralised/decentralised |
Decentralized |
Heating recovery ratio |
75 |
Energy source |
Electricity |
Primary energy consumption |
120908.00 kWh/year |
Primary energy consumption (ref. building) |
698298.00 kWh/year |
Specific primary energy consumption |
23.70 kWh/m2/year |
Specific primary energy consumption (ref. building) |
137.00 kWh/m2/year |
Differentiated specific primary energy demand and production
Accumulated specific primary energy demand and production
Efficient envelope and systems for Passive House cost a premium of 30 % compared to conventional envelope and systems. However, when the cost is normalised including the land cost, construction cost and other ancillary costs the premium comes down to 10.5 % and is approximately € 296/m2.
Envelope costs |
517469 EUR |
Systems costs |
190013 EUR |
Total investment costs |
707482 EUR |
Cost: |
138.00 EUR/m2 |
Total differentiated annual costs |
53917 EUR |
Specific differentiated annual costs |
10.00 EUR |
Yearly energy costs |
2998 EUR/year |
Cost and cost effectiveness
The area saved due to the implementation of innovative energy systems and minimized service areas led to more saleable space and thus offered a bargain for the extra premium. In addition, heating subsidy offered by local finance scheme and recurring reduced energy bills offer an attractive pay back period for the capital. The passive house is expected to save heating energy costs of approximately € 56,481 per annum.
Investment cost
Absolute building investment costs
Specific building investment cost
Annual Costs
Absolute annual costs
Specific annual cost
Assumptions
Local Currency |
CNY |
Currency rate to EUR |
0.12000 (March 25, 2013) |
Energy prices
Electricity |
0.0620 EUR/kWh |
Gas |
0.0270 EUR/kWh |