2. PASSIVE VS ACTIVE DESIGN STATERGIES IN
ENEGY EFFICIENT BUILDINNG
▪ PASSIVE DESIGN IS A SYSTEM OR STRUCTURETHAT DIRECTLY USES
NATURAL ENERGY SUCHAS SUNLIGHT,WIND,TEMPERATURE
DIFFERENCESORGRAVITYTOACHIEVEA RESULTWITHOUT
ELECTRICITYOR FUEL. ACTIVE DESIGN IS A SYSTEM OR STRUCTURE
THAT USES OR PRODUCES ELECTRICITY.
▪ THETERM PASSIVE DESIGN IS MOST OFTEN USEDWITH RESPECTTO
ARCHITECTUREAND INFRASTRUCTURE. FOR EXAMPLE,A BUILDING
MAY HAVEWIDEWINDOWSTHAT AUTOMATICALLY LET IN MORE
LIGHTWHENTHE BUILDING NEEDS HEAT ANDAUTOMATICALLY
SHADEWHENTHE BUILDING ISTOO HOT.
▪ ACTIVE DESIGN IS AN INFRASTRUCTURE,ARCHITECTUREAND
DEVICESTHAT USE OR PRODUCE ELECTRICITYTO ACHIEVEA
RESULT.
▪ MOST DEVICESAND INFRASTRUCTURE HAVE ANACTIVE DESIGNAS
THEY USE ELECTRICITY.THETERM ISTYPICALLY ONLY USED IN
COMPARISONTO PASSIVE DESIGN. FOR EXAMPLE, SOLAR PANELS
THAT PRODUCE ELECTRICITYAREOFTEN REFERREDTOAS ACTIVE
SOLARAS A COMPARISONTO USING SOLAR PASSIVELY FOR HEAT
ORTOGROW PLANTS.
3. PASSIVE DESIGN STRATEGIES
▪ ADAPTIVE RE-USE
▪ ADAPTIVE RE-USE, MOST SIMPLY PUT, IS CHANGINGTHE USEOF SOMETHING
WHICHWE NO LONGER NEEDTO SOMETHING NEW,WHICHWE NEED NOW
,WETHER IT BETHE UPCYCLINGOF MATERIALSOR CHANGING FUNCTIONOF
EXISTING BUILDING.
▪ HERITAGECONSERVATION
▪ HERITAGECONSERVATION ISA STRONG CONTRIBUTORTO SUSTAINABLE
DEVELOPMENTSTRATEGIES. ECONOMICALLY, IT CAN PROMOTE JOBGROWTH IN
SKILLEDTRADES, INCREASE PROPERTYVALUES, REVITALIZE NEIGHBOURHOODS
ANDAWIDEARRAYOFTOURISMOPPORTUNITIES.CULTURALLY, IT ACTSASA
POINT OF PRIDEAND REFERENCETHATCAN HELP FOSTERAWARENESSAND
CONFIDENTCULTURALGROWTHTHAT RESPECTSTRADITIONSAND STORIESOF
THEAREA. ENVIRONMENTALLY, HERITAGECONSERVATION ENCOURAGESTHE RE-
USEOF EXISTING BUILDING MATERIALS BY EXTENDINGTHE LIFE OFA BUILDING
AND ITSCOMPONENTS, OR REHABILITATING DAMAGED BUILDING MATERIALS.
4. PASSIVE DESIGN STRATEGIES
▪ SITE OPTIMIZATION
▪ CAREFULCONSIDERATIONOF A BUILDING SITEWILL: MINIMIZETHE
DISTURBANCEONTHE LAND, PROTECTCURRENTVEGETATION,
MITIGATETHE NEED FOR ADDITIONAL INFRASTRUCTURE,AND
PROVIDEOPPORTUNITIES FOR DAYLIGHTING, SOLAR HEAT GAIN,
AND NATURAL SHADINGANDVENTILATION. IT IS IDEALTO SELECT
A SITEWHERE EXISTINGCOMMUNITY RESOURCES SUCH
AS:SCHOOLS, SHOPPING, EMPLOYMENT, ENTERTAINMENT, PUBLIC
TRANSIT ROUTES,AND EXISTING INFRASTRUCTURE (ROADS,
5. PASSIVE DESIGN STRATEGIES
▪ PASSIVE SOLAR
▪ PASSIVE SOLAR DESIGN REFERSTOTHE USE OFTHE SUN’S ENERGY FORTHE
HEATING AND COOLING OF LIVING SPACES. INTHIS APPROACH,THE
BUILDING ITSELF, OR SOME ELEMENT OF IT,TAKES ADVANTAGE OF NATURAL
PROPERTIES OF MATERIALS AND AIR CREATED BY EXPOSURETOTHE SUN.
EXAMPLES INCLUDE OPERABLEWINDOWS PLACED FOR OPTIMAL HEAT GAIN
INWINTER, SHADING DEVICESAND SOLAR CHIMNEYS FORTHE SUMMER,
ANDTHERMAL MASS FOR BOTH SEASONS. SOLAR CHIMNEYS CREATE OR
REINFORCETHE EFFECT OF HOT AIR RISINGTO INDUCE AIR MOVEMENT FOR
COOLING PURPOSES.THE RESULTING SUCTION PULLSCOOLER AIR INTOTHE
BUILDING FROM LOWER, SHADED SPACES.
6. PASSIVE DESIGN STRATEGIES
▪ THERMAL MASS
▪ THERMAL MASS IS A PROPERTY OF A MATERIAL’S ABILITYTO ABSORB,
STORE, AND RELEASE HEAT. THERMALLY MATERIALS SUCH AS CONCRETE
HAVE A HIGH CAPACITYTO ABSORB ANDTO STORE EXCESS HEAT, OFTEN
FROMTHE SUN, WHICH IS MASSIVE BUILDING RELEASED INTOTHE
OCCUPIED SPACEWHENTHE AMBIENTTEMPERATURE FALLS BELOWTHAT
OFTHETHERMAL MASS. MOST MATERIALSWHICHWILLABSORB EXCESS
HEAT, WILLALSO ABSORB EXCESS HUMIDITY.THERMAL MASS MATERIALS
PASSIVELYACT ASTEMPERATURE AND HUMIDITY FLYWHEELS, REDUCING
INDOORTEMPERATURE AND HUMIDITY FLUCTUATIONS WITHOUTTHE
CONSUMPTION OF ENERGY
7. PASSIVE DESIGN STRATEGIES
▪ DEEP OVERHANGS
▪ PROPER WINDOW SHADINGWILL ALLOW
OPTIMAL SOLAR HEAT GAIN INTHEWINTER,
WHILE LIMITING UNWANTED SOLAR HEAT GAIN
DURINGTHE SUMMER. A CORRECTLY SIZED
ROOF OVERHANG WILL COMPLETELY SHADE A
WINDOW AT SOLAR NOON,WHENTHE SUN IS
AT IT'S HIGHEST.
8. PASSIVE DESIGN STRATEGIES
▪ NATURAL CROSS-VENTILATION
▪ NATURAL CROSS-VENTILATION OCCURS WHEN AIR ENTERS A BUILDING
THROUGH OPENINGS SUCH AS WINDOWS AND DOORS ON ONE SIDE, AND
EXITS ONTHE OPPOSITE SIDE. IT IS DRIVEN HORIZONTALLY BY POSITIVE
PRESSURE ONTHE WINDWARD SIDE AND NEGATIVE PRESSURE ONTHE
LEEWARD SIDE OFTHE BUILDING,ASWELLASVERTICALLYTHROUGH THE
BUILDINGVIA STACK EFFECT. NATURAL CROSS-VENTILATION REDUCES
ENERGY- CONSUMPTION FROM AIR CONDITIONING ANDVENTILATION
UNITS DURING SUMMER MONTHS. BUILDINGSARE IDEALLY DESIGNEDTO
ENCOURAGE NATURAL CROSS-VENTILATIONTHROUGHTHEIR
RELATIONSHIPWITH PREVAILING BREEZE PATTERNS.
9. PASSIVE DESIGN STRATEGIES
▪ RECYCLED MATERIALS
▪ RECYCLED MATERIALS ARE BUILDING MATERIALSTHAT HAVE BEEN
SALVAGED FROMTHE END-OF-LIFE OF ONEPROJECTTO BE GIVEN A NEW LIFE
ON A CURRENT PROJECT.
▪ EXTERIOR MATERIALS
▪ SELECTING DURABLE AND NATURAL EXTERIOR CLADDING MATERIALS AND
TREATMENTS TO WITHSTAND WEATHERING ANDTO EXTENDTHE
BUILDING’S LIFESPAN. UPONTHE END OFTHEIR REQUIRED USE SUCH
MATERIALSWILL IDEALLY BE RETURNEDTOTHE BIOSPHEREWITH POSITIVE,
RATHERTHAN ADVERSE, EFFECT.
10. PASSIVE DESIGN STRATEGIES
▪ GREEN ROOF
▪ • GREEN ROOF (ALSO KNOWN AS LIVING ROOF) SYSTEMS REFER TO THE PARTIAL OR COMPLETE COVERING OF A
BUILDING’S ROOF WITH WELL-SELECTED VEGETATION PLANTED IN A SUITABLE GROWING MEDIUM SPREAD OUT
OVER ROOT BARRIER AND DRAINAGE LAYERS, INSTALLED OVER THE ROOF’S WATERPROOFING MEMBRANE.
AUTOMATED IRRIGATION SYSTEMS CAN ALSO BE INTEGRATED FOR EASE OF MAINTENANCE. GREEN ROOFS
CONTRIBUTE TO THE REDUCTION OF URBAN HEAT ISLAND EFFECT, STORM WATER RETENTION,
RAINWATERFILTRATION, ROOF MEMBRANE PROTECTION, AND TO KEEPING A BUILDING COOL THROUGH
EVAPOTRANSPIRATION
▪ . • INDOOR MATERIALS
▪ • INTERIOR MATERIALS ARE SELECTED FOR LOW EMISSIONS (LOW- TO NO-VOLATILE ORGANIC COMPOUNDS
(VOCS) AND NON OFF-GASSING), RESULTING IN HEALTHIER INDOOR AIR. • THE RECYCLED CONTENT AND END-OF
LIFE RECYCLABILITY OF INTERIOR MATERIALS IS ALSO CONSIDERED TO REDUCE CURRENT AND FUTURE WASTE TO
LANDFILLS, AND REDUCE EXTRACTION OF VIRGIN NATURAL RESOURCES.
11. ACTIVE DESIGN STRATEGIES
▪ • GEOTHERMAL HEAT EXCHANGE
▪ • GEOTHERMAL HEAT EXCHANGE BRINGS A BUILDING IN HARMONY WITH THE EARTH, TAKING
ADVANTAGE OFSUBTERRANEAN TEMPERATURES TO PROVIDE HEATING IN THE WINTER AND COOLING
IN THE SUMMER. OUTDOOR TEMPERATURES FLUCTUATE WITH THE CHANGING SEASONS BUT
UNDERGROUND TEMPERATURES (FOUR TO SIX FEET BELOW GROUND) DON’T CHANGE AS
DRAMATICALLY, THANKS TO THE INSULATING PROPERTIES OF THE EARTH. AGEOTHERMAL SYSTEM,
WHICH TYPICALLY CONSISTS OF AN INDOOR HANDLING UNIT AND A BURIED SYSTEM OF PIPES, CALLED
AN EARTH LOOP, AND/OR A PUMP TO REINJECTION WELL, CAPITALIZES ON THESE CONSTANT
TEMPERATURES TO PROVIDE “FREE” ENERGY
▪ . • WIND POWER
▪ • WIND POWER IS GENERATED USING TURBINES OR WINDMILLS TO HARVEST WIND ENERGY TO
CONVERT IT INTO ELECTRICAL ENERGY.
12. ACTIVE DESIGN STRATEGIES
▪ GRID CONNECTED
▪ • A GRID-CONNECTED BUILDING GENERATES ELECTRICITY FOR USE ON SITE. WHEN ELECTRICITY
GENERATION EXCEEDS THE AMOUN TREQUIRED, THE SYSTEM SUPPLIES THE EXCESS POWER TO THE
UTILITY GRID. CONVERSELY, WHEN THE ELECTRICITY DEMANDS OF THE BUILDING EXCEED THE
AMOUNT SUPPLIED ON SITE, ELECTRICITY CAN BE DRAWN FROM THE POWER GRID. OPTIMALLY, A
GRID- CONNECTED BUILDING CAN BE NET-ZERO (OR NET-POSITIVE), MEANING THAT THE AMOUNT OF
ELECTRICITY SUPPLIED TO THE GRID IS EQUAL TO (OR GREATER THAN) THE AMOUNT DRAWN FROM
THE GRID. WITH THE HYDRO ONE NET METERING PROGRAM, ELECTRICITY GENERATED BY A BUILDING
CAN BE SENT TO HYDRO ONE'S DISTRIBUTION SYSTEM FOR A CREDIT TOWARDS ELECTRICITYCOSTS.
▪ • NET-POSITIVE COST OF ENERGY
▪ • WE RECOMMEND SOLAR PHOTOVOLTAIC (PV) MODULES WHEN THE CHOSEN SITE AND PROJECT ARE
SUITABLE TO HARVEST SOLAR ENERGY. PROJECTS THAT GENERATE ELECTRICITY CAN BECOME PART
OF THE HYDRO ONE NET METERING PROGRAM, WHICH WILL PROVIDE A CREDIT TOWARDS YOUR
ELECTRICITY COSTS. NET-POSITIVE COST OF ENERGY MEANS THAT WITHIN THE PERIOD OF ONE YEAR,
A PROJECT GENERATES ENOUGH ENERGY TO EXCEED THE COST OF ENERGY THEY PAY
13. ACTIVE DESIGN STRATEGIES
▪ SOLAR-ELECTRICAL POWER
▪ • SOLAR ELECTRICAL POWER IS GENERATED BY PHOTOVOLTAIC (PV) MODULESTHAT
HARVEST ENERGY FROMTHE SUN AND CONVERT IT INTO ELECTRICAL ENERGY. FOR USE
IN BUILDINGS, SOLAR MODULES CAN BE INTEGRATED INTOTHE DESIGN AS CLADDING
COMPONENTS OR AS SUN-SHADES, MOUNTED ONTHE ROOF, OR MOUNTED ON LAND
ADJACENTTOTHE BUILDING.TRACKING DEVICES CAN FOLLOWTHE PATH OFTHE SUN
FOR OPTIMAL EXPOSURE
▪ . • SOLARTHERMAL ENERGY
▪ • SOLARTHERMAL ENERGY IS HEAT ENERGY GENERATED BY A ROOF-MOUNTED SOLAR
COLLECTION DEVICETHAT ABSORBS HEAT FROMTHE SUN. FLAT-PLATE COLLECTORS
ARETHE MOST COMMONTYPE,WHERE FLUID IS CIRCULATEDTHROUGH TUBINGTO
TRANSFER HEAT FROMTHE COLLECTION SURFACETO AN INSULATED WATERTANK.THIS
STRATEGY CAN BE USEDTO PRE-HEATWATER FROMTHE MUNICIPAL MAIN, ORWELL,TO
DECREASETHE AMOUNT OF ENERGY NEEDED BY AN ON-DEMAND WATER HEATER.
14. ACTIVE DESIGN STRATEGIES
▪ HIGH EFFICIENCY HVAC SYSTEM
▪ • AN HVAC SYSTEM REFERSTO MECHANICAL SYSTEMS FOR HEATING,VENTILATION &
AIR CONDITIONINGTO MAINTAINTHE DESIRED ENVIRONMENTAL CONDITIONS WITHIN A
SPACE.THERE ARE MANY DIFFERENT SYSTEMSAVAILABLE BUT SHOULD BETUNEDTO
THE BUILDING’S NEEDS.WHERE POSSIBLE, PASSIVE STRATEGIES AND LOW-ENERGY
SYSTEMS FOR HEATINGAND COOLING ARE UTILIZED TO REDUCE ENERGY DEMAND.
PASSIVE STRATEGIES FOR SUMMER SEASONS INCLUDE :REFLECTIVE ROOF SURFACES,
AIR-TIGHTNESS AND GOODTHERMAL INSULATION. WHILE PASSIVE STRATEGIES FOR
WINTER SEASONS INCLUDE:THERMAL BLANKETS ATWINDOWS, ANDTHE USE OF
THERMAL MASS.
▪ • HRV/ERV
▪ • HEAT RECOVERYVENTILATION (HRV) AND ENERGY RECOVERYVENTILATION (ERV) ARE
DEDICATEDVENITLATION SYSTEMSTHAT SUPPLY CONTINUOUS FRESHAIRTOYOUR
HOME. FRESH OUTDOOR AIR RUNSTHROUGHTHE HRV/ERVWHICH PRE- CONDITIONS
THE AIR BYTRANSFERRINGTHE HEAT (HRV) OR HEAT AND HUMIDITY (ERV) FROM STALE
EXHAUST AIR INTOTHE FRESH OUTDOOR AIR.THIS PROCESS SAVES ENERGY IN HEATING
AND COOLING, RESULTING IN LOWER ENERGY BILLS AND HEALTHIER INDOOR AIR.
15. ACTIVE DESIGN STRATEGIES
▪ BUILDINGAUTOMATION
▪ • BUILDINGAUTOMATION REFERSTOTHE COMPUTER NETWORKING OF
ELECTRONIC DEVICES DESIGNEDTO MONITOR AND CONTROLTHE HVAC,
SECURITY, FIRE & SAFETY, LIGHTING, HUMIDITY AND AUDIO-VISUAL
CONTROL SYSTEMSWITHIN A BUILDING. AUTOMATED BUILDINGSARE
OFTEN REFERREDTO AS “INTELLIGENT BUILDINGS”, “SMART BUILDINGS”,
OR (IF RESIDENTIAL)AS “SMART HOMES”.
▪ • HIGH-EFFICIENCYAPPLIANCES
▪ HIGH-EFFICIENCYAPPLIANCES MUST MEET REGULATEDTARGETS FOR
ENERGYCONSUMPTION. THESETARGETS ARE SET LOWERTHANTYPICAL
ENERGY-USE FORTHE SAME APPLIANCE. IN NORTH AMERICA,WE USE
ENERGY STAR AS A GUIDE FOR HIGH ENERGY-EFFICIENCY STANDARDS FOR
MOST HOUSEHOLD APPLIANCES.
16. ACTIVE DESIGN STRATEGIES
▪ GREYWATER RE-USE
▪ • GREYWATER ISATERM USEDTO DESCRIBEWATERTHAT
HAS BEEN USED FOR SHOWERING, BATHING, AND HAND-
WASHING. IT SOMETIMES INCLUDESWASTEWATER FROM
KITCHEN SINKSAND LAUNDRY, DEPENDINGON LOCAL
BY- LAWS. GREYWATER REUSE INVOLVESTHE
COLLECTIONANDTREATMENTOFTHISWATER FOR USE
INTOILET- FLUSHING,OUTDOOR IRRIGATIONAND
CONSTRUCTEDWETLANDS, REDUCINGTHE OVERALL
DEMAND FOR POTABLE (DRINKABLE)WATER. DRAIN
WATER HEAT RECOVERY CAN BE EFFECTIVELYCOUPLED
WITH GREYWATER REUSE FOR OPTIMAL ENERGYAND
RESOURCE-EFFICIENCY.
