Building Integrated PhotoVoltaics: Thin Film Applications Strengths: Incorporated into functional building elements
(facade/roof tiles), Ability to be semitransparent
Weaknesses: Manufacturing intensive, Lower Solar cell efficiency than typical panels
Vendors:
http://www.onyxsolar.com/ http://www.us.schott.com/architecture/english/products/photovoltaics/asi-thru.html
Hessen Vocational Center
http://www.hhs.ag/projekte--hessen-campus-vocational-training-center.en.html
Acadamie de Formation
http://www.perraudinarchitectes.com/projets/herne_allemagne/herne_allemagne.htm
Novartis Basel
http://www.arcspace.com/features/gehry-partners-llp/novartis-building/
DEFINITIONS Photovoltaic (PV) panels | panels made from semi-conductor material such as silicon, able to gather high concentrations of electrons. When a photovoltaic cell is exposed to sunlight, the impact of solar radiation onto the solar cell generates electricity.
STRATEGY+EQUIPMENT Solar cells are wired to manufacture a laminate, which is assembled into a protective weatherproof enclosure, thus making a photovoltaic module or 1solar panel. Modules may then be strung together into a 1photovoltaic array. Modules are assembled into arrays on some kind of 2mounting system, which may be classified as ground mount, roof mount or pole mount. A 3solar tracker tilts a solar panel throughout the day to take in the most light available. Trackers greatly enhance early morning and late afternoon performance though they are less effective in diffuse light. Systems designed to deliver alternating current need an 4inverter to convert the direct current from the solar modules. A 5backup generator may be installed.
Salvaged shipping container collects and stores solar energy
Solar water heater sits among solar panels
ADVANTAGES Green, renewable power in place of conventional fossil fuels without noise Some PV panels can last up to 25 years with maximum efficiency loss of only 18% Minimize energy losses caused by the long distance between power generation and power consumption
DISADVANTAGES Unpredictability of environmental conditions Battery banks are needed to store excess amounts of produced energy for later use and have a limited life and cannot be refurbished Relatively low efficiency level ranging between 12-20% To convert DC to AC, PV panel systems use expensive inverters Fragile panel system requiring ongoing professional maintenance Most helpful site: http://www.greenbuildingadvisor.com/blogs/dept/musings/introduction-photovoltaic-systems
active
W A L L A W O M B A G U E S T H O U S E Bruny Island, Tasmania, Australia | 1+2 Architecture | 2150 sq ft
strategy
P h o t o v o l t a i c
S y s t e m
The house is sited with its long side facing east to west in order to take in the sun’s rays in winter and the house is cooled by the predominant westerly winds during the warm season. A PV solar array is located atop a salvaged shipping container, which also houses all of the mechanical requirements, including the battery bank, inverter, and backup generator. The solar array accounts for the retreat’s general domestic power use.
Active: Solar Tracking with Concentrated Solar Power Description: The use of solar panels which have the ability to track the sun as it moves through the sky. Generally used in conjunction with concentrated solar power (CSP). CSP concentrates large area of sunlight into small area. The resulting heat drives a heat engine which generates electricity.
Diagramming:
Precedence:
Solar Tracking
CSP Solar Tacking Field
Advantages: - Solar tracking allows for more electricity to be generated because it tracks the sun throughout the day - Many areas have rebates and incentives for implementation of solar systems - California in particular - Solar fields can be used to generate large amounts of electricity
Disadvantages: -Fairly long payback period (12-20 years) - Relatively high initial cost - Reduced sun exposure in cloudy/foggy conditions -Difficult to integrate into design of building - Better suited for off site use production
Concentrated Solar Power
surface mounted fan
air to air heat exchanger
balanced ventilator
active: automated ventilation
remote mounted in-line fan
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remote mounted multiport fan
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exhauste air heat pump
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helps maintain overall indoor air quality. helps maintain a comfortable humidity level regulates indoor air quality and comfort helps to maintain air temperature replenishes oxygen set it and forget it Homes are far more airtight nowadays, leading to a new emphasis on the need for indoor air quality. Poor circulation within a home means fresh air doesn’t get to where it’s most needed, like bedrooms Exhaust-only ventilation causes pressure imbalance inside the home, not always desirable Drawing air in through the walls introduces the risk of moisture condensation inside the walls, especially if there’s a big temperature differential between outside and inside air. Twenty-four hour timers allow the occupants to set certain times for ventilation. Set the timer to run the fan at least eight hours per day. Indoor air quality sensors activate a fan when they detect carbon monoxide, formaldehyde or other pollutants.
AUTOMATED VENTILATION DIFFERENT ELEVATIONS OF THE BUILDING HAVE DIFFERENT SYSTEMS. ON THE SOUTH SIDE, LARGE PHOTOVOLTAIC PANELS FORM A BRISE-SOLEIL. ON THE EAST AND WEST FACADES, PERFORATED SOLAR-SHADING SCREENS HANG A FOOT FROM THE EXTERIOR WALL. WHEN THEY HEAT, AIR AROUND THEM RISES, WHICH DRAWS COOLER AIR FROM GROUND LEVEL. EACH DAY, ABOUT 1,000 SCREENS, WHICH ARE LOCATED IN FRONT OF WINDOWS, OPEN AND CLOSE. THE RESULT COMBINES A LARGE PHOTOVOLTAIC ARRAY AND INDEPENDENTLY CONTROLLED, AUTOMATED ELEMENTS WITHIN A MULTIPLE-LAYER FACADE. THE PROMINENT SHADING LAYER OF PERFORATED METALLIC PANELS ON EAST AND WEST FACADES CUTS INITIAL SOLAR HEAT GAIN BY ABOUT 15 PERCENT. THE SCREEN HANGS ABOUT 1 FOOT FROM THE SLAB EDGES OF A WEATHER-WALL OF METAL FRAMING, GYPSUM SHEATHING, AND PVC MEMBRANE. IN THIS WAY, THE INTERVENING SPACE FUNCTIONS PARTLY AS CONVECTIVE CAVITY. ONE THOUSAND OR SO OF THE SCRIM PANELS, CORRESPONDING TO RIBBON WINDOWS BEHIND, OPEN OR CLOSE DAILY. THOSE ON THE EAST CLOSE IN THE MORNING, THOSE ON THE WEST IN THE AFTERNOON. FOR LONGEVITY, THE ARCHITECTS SPECIFIED STAINLESS-STEEL HARDWARE AND A SINGLE PNEUMATIC LIFT PER PANEL, RATHER THAN THE PAIR OF ELECTRICAL ACTUATORS ORIGINALLY CONSIDERED. A ROOFTOP SENSOR SIGNALS THE PANELS TO CLOSE DURING HIGH WINDS.
CALTRANS DISTRICT 7 HEADQUARTERS MORPHOSIS
Active System: Solar Tubes
A solar tube is a type of skylight that brings natural light into a space from outside the building, without having direct sunlight acting as a heat source to raise the temperature of the space. A glass dome collects light from the roof (typically), and a reflective hollow tube that connects the dome and the light fixture brings light down and into the space through a diffuser, which spreads the natural light evenly throughout the space. When it gets darker or is cloudy, a sensor in the tube will activate an LED light in the tube to subsidize the reduced amount of daylight coming in.
Benefits of solar tubes: -Improved daylighting for interior spaces. -Reduced energy usage due to less artificial lighting used. -Reduced cooling load due to less heat coming from lights. -Potential energy storage from solar collection.
Northeast Elementary School Location: Parker, CO Built: 1967 Solar Tubes Installed: 2013 This elementary school in Parker, CO, a part of Douglas County School District, elected to install 84 solar tubes to bring natural light into the classrooms. 3-4 solar tubes were installed in each classroom, along with a 9’ x 9’ skylight in the library. These systems are able to help the school save money on electricity, and use that money to go back into books and other needed materials. (Google Earth image predates installation of solar tubes)
Geothermal Technologies
“Technology related to the transfer of energy from heat inside the Earth, usually carried to the surface by superheated water and steam.” BENEFITS
Geothermal House by Architect: Maryann Thompson Boston, Massachusetts
renewable source of energy produced by the heat of the earth and often associated with volcanic and seismically active regions ground-source heat pumps provide a way to tap into geothermal energy providing heating and cooling which takes advantage of the constant ground temperature (50°F) that is within a few feet below the ground’s surface no fuel is required for the geothermal pump, instead air or antifreeze liquid is pumped through pipes buried underground, and re-circulated into the building; in the summer the liquid moves heat from the building into the ground and in the winter, it does the opposite providing pre-warmed air and water to the heating system U.S. Geological Survey estimates that in the U.S. 30 GW of undiscovered hydrothermal resource capacity and more than 100 GW of the geothermal energy potential lies within the subsurface, equal to 10% of the U.S.’s energy needs
FEATURES
U.S. has more geothermal capacity than any other country, with more than 3,000 megawatts in eight states, 80% percent of this capacity is in California
geothermal system supplies heating, cooling, and hot water for the entire house
geothermal energy can cut cooling and heating costs by 20-80% percent depending on the efficiency rating of the heat pump installed, while heat pump may pay for itself (typically within 10 years)
super insulated design of north facing walls capture warmth and keep out the cold
organized on the site to take advantage of the daily path of the sun
geothermal energy heat pumps can be used to heat water, saving even more money
south facing walls open up to let in sun
the use of geothermal systems substantially reduces the amount of pollution, as this method of heating is very close to being emission free
deep overhangs control heat loss and gain
There are no fluctuations in the heat or cooling capabilities due to the consistency of the ground
passive design strategies further support the sustainable nature of the geothermal system, often making it not necessary to turn the geothermal system on
geothermal energy has the smallest carbon footprint of any of the major power sources
orientation of rooms an operable fenestrations create cross-ventilation through the home
the geothermal system saves approximately 60% of the home’s energy costs
LIMITATIONS geothermal is a relatively new concept for private home use therefore it is still expensive to install (high upfront costs) geothermal energy systems require quite a bit of land in order to have them properly installed, the pipes are typically laid out in a horizontal pattern, however at a higher installation cost they can be laid vertically locations where geothermal systems can be installed is specific which does not allow the use of geothermal for all projects a minimum temperature requirement of at least 350°F for the system to perform at optimum levels
due to the water piping system in the floor and the sun coming into the house through the windows, the floors are often warmed without the need for heat the typical Boston winters often do not require the use of the geothermal heating in this 8,000 sqft home, proving the efficiency of the home’s design the home has a regular, back-up heating system that is rarely utilized due to the efficiency of the geothermal system
the use of electricity to power the heat pump is still required in order to make the system work
Active Systems
Geothermal
Shannon Ferguson
active: radiant floor heating
underfloor hot water tubes or electric wires used to heat spaces rather than blowing air which results in striations of temperatures, surfaces are heated which radiates to heat the room heating through contact, body heat no longer taken from touching surfaces
• what is it?
electric: zigzagging loops of resistance wire, generally retrofitted to a single room hydronic (hot water): most popular and cost effective way to heat an entire house circulates water from a boiler or water heater through loops of 1/2-inch polyethylene tubing can be installed various ways (on top, clipped, embedded) costs more to install ($6 to $15/sq ft) benefits: no duct work easy to install in an existing space no noise even spread of heat across a space can be up to 30 percent more efficient than forced-air heating options/add-ons: multiple heating zones (for per room control) outdoor reset control (responds to outside temperatures
• precedent: yin yang house 1348 Appleton Way Venice California 90291 United States Submitting Architect: Brooks + Scarpa Project Completion Date: April, 2011 Project Type: Mixed – Use the building program: nearly net-zero energy live/work home and office home and commercial office for a large family place to entertain and a welcoming space for clients and teenagers designed to incorporate sustainable design as a way of teaching a green lifestyle organized around a series of courtyards and outdoor spaces that integrate with the interior of the house active strategies: radiant floor heating used throughout the house as the sole means of heat generation regulates temperature for both natural heating and cooling the building has no mechanical cooling system. As a result, heating and cooling loads are reduced by over 75%
Views of SE portion of house - Photo Credit: John Linden
photographs taken from AIA “Top Ten”, http://www.aiatopten.org/
Thermally broken radiant slab ready for 50% flyash toping slab - Photo Credit: Lawrence Scarpa
Main living space looking towards kitchen and pantry - Photo Credit: John Linden
Thermally broken slab detail - Photo Credit: Lawrence Scarpa
Active System
Radiant Floor Heating
Types of Systems THE CLOSED HEATING SYSTEM
This system, dedicated exclusively for space heating, uses a boiler or water heater to heat water which is circulated through the in floor tubing. This is a familiar and conventional approach that is well accepted by building code officials.
In a radiant floor heating system, warm water flows through tubes located underneath the floors. That warmth radiates up from the floors and warms everything it comes in contact
THE INDIRECT HEATING SYSTEM
This system uses a high efficiency water heater for both space heating and domestic hot water needs while keeping the two systems separate by using a heat exchanger.
Forced Air vs. Radiant Heat
THE OPEN DIRECT HEATING SYSTEM
This system uses a high-efficiency hot water heater to provide hot water for space heating and domestic hot water within a single system. There are significant advantages in terms of initial cost, fuel efficiency, simplicity and environmental friendliness.
Graphic showing heat temperature changes between a normal forced-air system and radiant heat flooring.
Outcome
Radiant Air Floors - Don't hold large amount of heat, and for this reason they are used mainly in commercial buildings. WIll need a different system for each zone. The cost of each independent zone is $300-$400. Radiant floor systems operate more efficiently at a lower thermostat setting than forced-air systems
Benefits
Distributes heat evenly around the floor where people are located No drafts as well as noisy fans, furnaces or ductwork
Floor Systems
Slab on Grade: Puts out 50 BTUs/ sq. ft. Stapled system (floor joists): Puts out 35 BTUs sq. ft.
No circulation of dirt, dust or other airborne pollutants throughout the building
Facts
Water in a radiant system has a capacity to transport energy 3,500 times greater than air Residential and Small Commercial buildings only need 25 BTUs/ sq. ft.
Can be used to heat and cool Solar heating systems can be easily integrated and have been proved quite successful with Radiant Floor Systems
Aesthetically pleasing environment as there are no ducts Can be integrated with other energy sources, including geothermal, solar, waste and biomass
Sources: Uponor, Radiantec
Active Design Geothermal: Thermal energy that is generated and stored in the Earth. One of the only renewable power sources that can supply ‘base load’ power, because it provides a constant rate of supply that isn’t affected by weather or seasonal variations. (source:http://www.carbonneutral.com/project-portfolio/geo-thermal) Creates less environmental pollution, is renewable and sustainable, avoids importing energy resources, benefits remote areas, adds to energy source diversity, creates less waste disposal and has a long life span. (http://academic.evergreen.edu/g/grossmaz/heidtken.html) Produced by drilling a well into the ground where thermal activity is occuring. Once a well has been identified and a well head attached, the steam is separated from the water, the water is diverted through a turbine engine which turns a generator. Usually the water is injected back into the ground to resupply the geothermal source.
Stepped Arrowtown House Architect: Kerr Ritchie
ARCA-Regler Germany Architect: Anin Jeromin Fitilidis and Partners This building was designed in a residential neighborhood. The intent was to not intrude on the local architecture. The building is climate controlled using geothermal probes which reduces the need for heating and cooling. (source: http://inhabitat.com/double-skinned-arca-regler-facility-powered-by-geothermic-probes/anin-jeromin_fitilidis-arca2/?extend=1)
Constructed in different levels to adapt to the sloping terrain, it features plenty of double glazed windows that help with energy savings while pulling magnificent views of the surrounding mountains into the home. Created with passive solar principles, this unique multi-layered home also uses geothermal energy to bring down its carbon footprint (Source: http://inhabitat.com/stepped-arrowtown-house-in-new-zealand-uses-geothermal-power-and-passive-heating-and-cooling/kerr-ritchie-geother mal-energy-arrowtown-house-2/?extend=1)
ACTIVE: SOLAR HOT WATER HEATING Project_Muse Passivhous by Bere Architects London, England 2002 Active solar water heating system This home built for Bere Architects owner Justin Bere and family uses a powerful active solar water heating system which supplies heat for all residential needs as well as heat to the 36’ long swimming pool. Basic solar heating requirements: a. solar array b. solar collector loop of copper or stainless steel piping c. water storage tank Passive or active systems are available. Passive systems uses gravitational and natural forces to move water through the system, providing the heated water. Active systems use electricity and control systems to push water through the collector loop to be heated. They can include either antifreeze or distilled water as a heat water fluid which is circulated through pipes in the storage tank, heating the water.
Active System: Solar Hot Water Flat-plate collector Glazed flat-plate collectors are insulated, weatherproofed boxes that contain a dark absorber plate under one or more glass or plastic (polymer) covers.
Building Integrated Solar Hot Water Designers no longer need to sacrifice aesthetics to achieve the benefits of building integrated thermal systems. Hybrid Shades feature a proprietary, building-integrated, solar thermal system generating free solar hot water while shading and integrating seamlessly to any facade’s design.
Can provide an energy savings of 30% on cooling costs and 50% and more on water heating costs based upon model.
Integral collector-storage systems Also known as ICS or batch systems, they feature one or more black tanks or tubes in an insulated, glazed box. Cold water first passes through the solar collector, which preheats the water. The water then continues on to the conventional backup water heater, providing a reliable source of hot water. They should be installed only in mild-freeze climates because the outdoor pipes could freeze in severe, cold weather.
Evacuated-tube solar collectors They feature parallel rows of transparent glass tubes. Each tube contains a glass outer tube and metal absorber tube attached to a fin. The fin’s coating absorbs solar energy but inhibits radiative heat loss. These collectors
The solar collectors within the Hybrid Shade Structures connect to the plumbing system of the building and harness the sun’s energy, transform its radiation into heat, then transfer that heat to water to generate free solar hot water.
Chilled Beams Emgp Active Design Strategy
What is it
paris,france -Building conditioning system that uses convection and water to move energy -Cooling + Heating -Induction nozzles
Components
-sensible heat transfer coil -linear slots
Assembly
Advantages
How it works
t-Bar Ceiling grid
-no noise -no fans -no filters -no condensation -low maintenance -flexibility/adjustability
Greywater Reuse Greywater Sources - Bathroom sinks, showers, tubs, washing machines
Advantages -
The nutrients in greywater can be beneficial to plants Reduces dependence on external water sources Reduces dependence on sewer and septic systems A simple system can rely on nothing more than gravity- avoid pumps and filters to reduce maintenance and energy use
Concerns -
It is essential that occupants do not put anything toxic down the drain Greywater can not come from sources that come into contact with feces – i.e. toilets If released into waterways, the nutrients in greywater become pollutants Ideally, a landscape should allow water to infiltrate the soil. Greywater should not be stored more than 24 hours
Michael Reilly 10/14/2013