The Waban Green Home House of the Future: Net-Zero Energy, LEED - - PowerPoint PPT Presentation

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Environmental Entrepreneurs

The Waban Green Home House of the Future:

Net-Zero Energy, LEED Platinum, Walking Distance to the T

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Our purpose for building the house

Who we are

– Family of 4 (dog pending) – Two home offices – Frequent guests (9 people lived in house over holidays)

To do our part in mitigating climate change

– The most important responsibility of our generation

To live in a house that reflects our values

– Gives back as much as it consumes – Is sustainable and in tune with the natural world – Is beautiful inside and out – Is comfortable, healthy and fun to live in

To demonstrate that a net-zero energy house can

be built without compromise

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Building shape, orientation and size

• House size

– For houses in same neighborhood zoning built within last 10 yrs

• Median living area: 4,553 sq ft (22 houses)
• Our living area: 3,896 sq ft (29th percentile)

House size

– For houses in same neighborhood zoning built within last 10 yrs

• Median living area: 4,553 sq ft (22 houses)
• Our living area: 3,896 sq ft (29th percentile)

Solar Orientation

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Achieving Zero-Net-Energy

Building envelope (R20/R40/R60)

– R20+ foundation, R40+ walls, R60+ roof – Complete air sealing – Edges and corners are problematic…

ERV (energy recovery ventilation)

– Intentional better than unintentional

Southern orientation

– Optimizes passive solar heating & PV

Optimized windows

– Triple pane, gas fill, glazed by orientation

Daylighting

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Achieving Zero-Net-Energy

Solar thermal panels

– Extremely cost efficient hot water

Solar PV

– With MA and Federal incentives, IRR 11-22% and payback w/in 4-8 yrs

Air source heat pump (ASHP)

– Mini-split system w/outside variable speed compressors and multiple indoor air handlers – Nominal COP of 3.2 – COP of 2.5 at 0 degrees F

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Achieving Zero-Net-Energy

Open atrium between floors and ceiling fans

– Ceiling fans provide energy efficient cooling

Lighting (CFLs -> LEDs)

– Warm, dimmable, and lasts many years

Appliances: Energy Star and better

– See http://www.energystar.gov/

User behavior

– Home automation makes it easy to live efficiently

See product and service list!

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Sustainability

Location, location, location!

– Public transportation – Walk score (http://www.walkscore.com/ )

Landscaping

– Native plants – Recycled, light colored hardscapes

Recycling

– Recycled prior structure and construction material

• Craigslist method

– Use of recycled materials for driveway, countertops, etc…

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Sustainability

FSC Lumber

– The majority of the mass of the house – Can trust that it was sourced right

Indoor air quality

– Minimize VOCs (paints, finishes, rugs) – Minimize formaldehyde (doors, cabinets) – No shoes in house

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Policy Suggestions

HERS rating requirement

– For sales, rentals or financing

Building codes

– Reduce the max base code HERS rating

Address regulatory barriers

– Should be easier rather than harder to get building permits for energy efficient practices and technologies

Make it easier to monitor energy use

– Can’t manage what’s not being monitored

MassSAVE should expand and provide a loan fund

– So every home should have benefits and cost savings of super- insulation

From: Getting to Zero: Final Report of the Massachusetts Zero Net Energy Buildings Task Force

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Waban Green Home Energy Use and Production

The last week…

Powerhouse Dynamics energy monitoring system

February days where we’re using less energy than we’re producing…

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Utility Meter Readings

2070 2080 2090 2100 2110 2120 2130 2140 2150 2/3/12 0:00 2/4/12 0:00 2/5/12 0:00 2/6/12 0:00 2/7/12 0:00 2/8/12 0:00

Utility Meter Readings February days where we’re using less energy than we’re producing…

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Waban Green Home Performance

December and January energy usage compared to home we moved from (built to code in 2005, and which had less square footage)

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 Home built in 2005 Waban Green Home

Heating kWh per Sq Ft for December & January

88% less energy needed for heat and hot water 37% less energy needed for everything else

0.00 200.00 400.00 600.00 800.00 1000.00 1200.00 1400.00 1600.00 1800.00 2000.00 Home built in 2005 Waban Green Home

All Other Energy Use