concept related to net zero energy buildings

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2. InstituteofTechnology&Management,
Maharajganj
Presented by: Saroj Khadka
4th year, Civil Engg.
1047200059
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3. Contents
 Net Zero Energy Buildings
 Classify ZEBs by Renewable
Energy supply
 Zero Energy Buildings in
World
 Design strategies for low and
net zero energy buildings
 Sustainable system included in
building
 Solar array system on roofs
 Advantages of Zero energy
buildings
 Disadvantages of Zero energy
buildings 3

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5. NetZeroEnergybuildings(NzEb)
 Net Zero Energy buildings means the
buildings generate as much energy
and power as it consumes on annual
basis.
 NZEB is a grid-connected and energy-
efficient building that balances its total
annual energy needs by on-site
generation.
 Main concept of ZEB, 100 % of
energy it requires come from low
cost, locally available, non polluting,
renewable energy sources, even of
energy is generated off the site.
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6. Fourwell-documenteddefinitions:
 Net Zero Site Energy (site ZEB) :
Amount of energy provided by on-site renewable energy sources is
equal to the amount of energy used by the building.
 Net off-site zero energy (off-site ZEB):
Similar to previous one, but consider purchasing of energy off-site from
100% renewable energy sources
 Net zero energy costs (cost ZEB):
The cost of purchasing energy is balanced by income from sales of
electricity to the grid of electricity generated on-site.
 Net zero energy emissions:
Zero carbon building or zero emission building
The carbon emissions generated from the on-site or off-site fossil fuel
use are balanced by the amount of on-site renewable energy
production.
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7. Classifying ZEBs by Renewable Energy Supply
ZEB
Classification
ZEB Supply-Side Options
A Use renewable energy sources available within the building’s footprint and dedicated to the
building
(Examples: Photovoltaic, solar hot water and wind located on the building.)
B Use renewable energy sources as described in ZEB:A
And/or
Use renewable energy sources available at the building site and dedicated to the building
(Examples: Photovoltaic, solar hot water, low-impact hydroelectric, and wind located on
parking lots, adjacent open space, but not physically mounted on the building.)
C Use renewable energy sources as described in ZEB:A;
and/or ZEB:B
And Use renewable energy sources available off site to generate energy on site and dedicated to
the building
(Examples: Biomass, wood pellets, ethanol, or biodiesel that can be imported from off site, or
collected from waste streams from on-site processes that can be used on site to generate
electricity and heat.)
D Use renewable energy sources as described in ZEB:A, ZEB:B, and /or ZEB:C
And Purchase recently added off-site renewable energy sources, as certified from Green-E
(2009) or other equivalent renewable energy certification programs. Continue to purchase the
generation from this new resource to maintain ZEB status.
(Examples: Utility-based wind, photovoltaic, emissions credits, or other “green” purchasing
options.All off-site purchases must be certified as recently added renewable energy )
On-Site Supply Options
Off-Site Supply Options
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8. Zeroenergybuildings
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9. Design strategiesoflow&netzeroenergybuildings
1) Building System Performance Design
 Good design practices reduce overall electrical energy demands
 THERMOMASS Insulation Building System/TEX-COTE cool wall
 Highly insulated roof system
 Day lighting, fenestration minimized on south wall/max on north
wall
 centralized mechanical/electrical rooms
 Energy efficient insulated window system
 HVAC and electrical system
2) Systems incorporated into the design as bid options.
 Solar Photovoltaic
 WindTurbine
 Rainwater harvesting
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10. Other Sustainable Systems Included in the
Building
Sustainable Systems
 Mechanical/plumbing
 Split DX HVAC with energy recovery technology
 HVAC system
 Rainwater harvesting, recovery and recycling, reuse in toilets
and urinals
 Water conserving fixtures, low flow, dual flush
 Electrical
 Day lighting controls and occupancy sensors
 Nighttime illumination with fluorescent & LED lighting
 Building is +42% more efficient than traditional buildings
 Photovoltaic System 10

11. Solar Array Installed on Roofs
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12. Solar Array System
 PV Crystalline Panel System
 PV Crystalline modules, utilizing
the most efficient panel at the
time of construction
 2.5’x5’ panel at 235 watts per
panel, 78,960 watts of power
 336 panels located on building
roofs
 Life expectancy of panels is 25
years on power output at 80%
 Expected payback period is 7 years
 Photovoltaic System located on
the roof act as an umbrella
 Panels protect the roof from
environmental damage
 Panels keep the roof cooler aiding
in smaller cooling demands
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13. Grid connected
wind energy
systems
Grid connected
PV systems
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14. ZeroEnergyOffice(ZEO)BuildinginMalaysia
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15. Zero energy office building in Guangdong, China
(Pearl River Tower, for Guangdong Tobacco
Company)
(completed in 2009)
Main features:
- Orientation of the
building
- Low-E-glass
- Double-layer curtain-
wall
- Chilled slab concrete
ceilings
- Lighting efficiency
- Geothermal heat sink
- Energy storage
-Wind
-Integrated photovoltaics
- Microturbines
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16. Singapore zero energy building –Building and
Construction Authority (BCA) Academy
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17. Energy design features:
- Triple glazed
- High thermal insulation
- 777 m² of solar panels
- Co-generation
- District heating &
electricity
Beddington Zero Energy Development (BedZED),
UK
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18. Self-sufficient solar house in Freiburg,
Germany
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19. Zero Energy Buildings
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20. The 1,700-sf Science House (at center in photo)
features an 8.8 kW photovoltaic array and ground-
source heat pumps. 20

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22. 1) Low ventilation intake
2) High ventilation exhaust
3 ) Spectrally selective glazing
in thermally broken frame
4) Day lighting in internal
hallway
5) Operable skylight
6) Peel-n-stick photo voltaic
7) 30 kW transformer
connected to electrical grid
8) Radiant slab heating
toilets
pump
cistern
transformer
grid
Chartwell School NZEB Strategies
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23. Section of a new office building, now under construction, for the
David and Lucile Packard Foundation, Los Altos, Calif. The
49,000-sf facility, which will house 120 employees, will use chilled
beams, a high-performance envelope, plug load reductions,
and a 285 kW photovoltaic system to achieve net-zero energy status and
LEED Platinum certification.
1) PV panels supply 100%
of renewable energy
2) Solar hot water panels
3) 40-foot width
maximizes day lighting
and natural ventilation
4) Dynamic exterior blinds
lower with direct sun
5) Layered shading
strategies
6) Triple-glazed, highly
insulating windows
7) Chilled beams with
100% fresh airCourtyard
Alley
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24. Advantages:
 Increased comfort due to more uniform interior temperatures.
 Improved reliability- Photovoltaic systems have 25 yrs warranties,
seldom failed during weather problems
e.g:Photovoltaic system on the Walt DisneyWorld EPCOT
Energy Pavilion are still working fine till today after going through
3 recent hurricanes.
 Reduce carbon emissions
 Reduce dependence on fossil fuels
 Reduce energy consumption and costs
 Value of ZEB Building relative to similar conventional building
should increase every time energy costs increase.
 Free from carbon emission taxes/ penalties and other future
legislative restrictions.
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25. Disadvantages:
 High initial cost.
 Few designers or builders have necessary skills or
experience to build ZEBS.
 Value of Photovoltaic solar cells equipment
technology price has been falling at roughly 17%
per year- it may lessen the value of capital invested
in solar electric system.
 Solar energy capture using house envelope only
works in locations unobstructed from south.
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26. Conclusion
 NZEBs are vital to the nation’s energy-efficient
future.
 To design and build an NZEB, energy efficiency and
renewable energy generation must be requirements
from the beginning.
 A cost-effective NZEB is a realistic possibility that
uses today’s technologies combined with an
integrated design process.
 For NZEBs, every watt counts, as saving a single
continuous watt with energy efficiency equates to
avoiding $33 in PV capital costs.
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27. bibliography
 http://www.nibs.org/
 http://www.nrel.gov/
 Building Envelope
(http://www.ornl.gov/sci/ees/etsd/btric/)
 Solar EnergyTechnologies
(http://www.ornl.gov/sci/eere/research_solar.shtml)
 Cooling, Heating and Power
(http://www.ornl.gov/sci/engineering_science_technol
ogy/cooling_heating_power/)
 Whole-Building & Community Integration Residential,
Commercial & Industrial Energy Efficiency
(http://www.ornl.gov/sci/ees/etsd/btric/residential.sht
ml
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