013_20160726_Overview of net zero energy buildings in the US

Overview of Net Zero Energy Buildings in the US

Jiazhen Ling, Reinhard Radermacher

Contents• Building Energy Ratings• Net Zero Energy Buildings and Examples• Technologies for NZEB• Cost Analysis• Incentives to NZEB• Others

Building Energy Ratings• Leadership in Energy and Environmental Design (LEED)

• Certified (40-49 points); Silver (50 – 59 points); Gold (60-79 points); Platinum (80 – 110 points)• Green Globes

• One Globe (350-540 points); Two Globes (550-690 points); Three Globes (700-840 points); Four Globes (850-1000 points)• Home Energy Rating System (HERS)

• Scale from 0 to 100; 0 indicates the building uses no net purchased energy; the lower the value, the better• Net Zero Energy Buildings

LEED ScoreboardPossible Points

(for homes)Possible Points(for Multi-family)

Integrative Process 2 2Location and Transportation 15 17Sustainable Sites 8 9Water Efficiency 13 13Energy and Atmosphere 34 30Material and Resources 11 9Indoor Environmental Quality 15 18Performance 2 2Innovation 6 6Regional Priority 4 4Total 110 110

Source: http://www.usgbc.org

Green Globes® Overview• A web-based program for green building guidance

and certification• The program supports new construction, existing

buildings and healthcare buildingsEnvironmental Assessment Area

New Construction points

Environmental Assessment Area

Existing Buildings Points

Energy 380 Energy 350Water 85 Water 80Resources 100 Resources 110Emissions 70 Emissions 175Indoor Environment 200 Indoor Environment 185Project Management 50 Environmental Management 100Site 115Total Points 1000 1000

Source: http://www.thegbi.org/green-globes/new-construction.shtml

Green Globes Versus LEEDCriteria Green Globes LEEDProgram Points 1000 110Program Delivery Web enabled interactive questionnaire Online formsIncorporate LifeCycle Assessment

YES NO

Certification Process Assessor assigned/on-site building audit with team

Fill out assessment form,

submit, await results

Certification Ratings 4 Globes3 Globes2 Globes1 Globe

LEED PlatinumLEED GoldLEED Silver

Certified LEEDTime Required to Complete DocumentationCost to Certify a Typical Bldg. > 100,000 sq. ft.

$ $$$

Source: http://www.thegbi.org/green-globes/green-globes-leed-green-building-certification.shtml

A Few Numbers• LEED Certified (as of: 10/2/2012)[1]

• LEED Platinum: 945 ; LEED Gold: 6215; LEED Silver: 5042; LEED Certified; 3023

• Green Globes:(as of: 10/2/2012)[2]• New Constructions:

• 4 Globes: 4; 3 Globes: 29; 2 Globes: 52; 1 Globes: 30• Existing Constructions:

• 4 Globes: 10; 3 Globes: 228; 2 Globes: 87; 1 Globes: 10

[1]: Public LEED Project Directory (http://www.usgbc.org/LEED/Project/CertifiedProjectList.aspx)[2]: Green Globes Overview (http://www.thegbi.org/green-globes/)

LEED Gold Buildings at UMCP

8

Net-Zero Energy Building Definitions• In general, a net-zero energy building

produces as much energy as it uses over the course of a year

• Net-zero energy buildings are very energy efficient

• The remaining low energy needs are typically met with on-site renewable energy

Types of NZEB• Net Zero Site Energy• Net Zero Source Energy• Net Zero Energy Costs• Net Zero Energy Emissions

Current Status of NZE Buildings in US• ZEB (or better low energy buildings)

research is currently being supported by US DOE Building America Program

• Other industry-based consortia and national laboratories such as NREL, LBNL, NIST and ORNL are also actively involved

• President Obama set up the goal that 100% of all new federal buildings achieve Zero-Net-Energy by 2030

US Roadmap towards nZEB• Executive Order 13514

• All new Federal buildings that are entering the planning process in 2020 or thereafter be “designed to achieve zero-net-energy by 2030• DOE defined two milestones

• Marketable Net Zero Energy Homes by the year 2020• Commercial Net Zero Energy Buildings at low incremental cost by the year 2025

• 100% reduction in fossil-fuel energy use (relative to 2003 levels) for new Federal buildings and major renovations by 2030

Worldwide Zero Energy TargetsCOUNTRIES (REGIONS) ZERO ENERGY TARGETUSA (California) Net zero energy performance in residential

buildings by 2020 and in commercial buildings by 2030

USA (Massachusetts) Net zero energy for all new buildings by 2030South Korea All residential buildings are required to achieve

zero energy emissions by 2025England Zero carbon (emissions) homes by 2016Wales Zero carbon (emissions) buildings ( in relation to

space heating, hot water and lighting) by 2011France By 2020 all new buildings are energy-positiveThe Netherlands Energy-neutral buildings in 2020Hungary Zero emissions for all new buildings by 2020

Source: Maria Kapsalaki & Vitor Leal (2011): Recent progress on net zero energy buildings, Advances in Building Energy Research, 5:1, 129-162

Approach for Achieving NZEB

Source: National Science and Technology Council, Federal Research and Development Agenda for Net-zero Energy, High-Performance Green Builings,2008

Analyzing the Least-Cost Path

Reduced cost by increasing building efficiency

Additional options until cost of saving energy equals cost of onsite power prod.

No changes in design, savings result from additional onsite power capacity

PV systems used for on-site power generation

Earlier NZE Houses – PVRES, Florida

Lakeland Zero Energy Home (solid circle); control home (dotted circle), built Lakeland , FL in 1998• Single family home (one story, 3BR,

2425 sq. ft.)• Two houses, one PVRES and one

control home, have the same floor plan

• PVRES has a 4 kW PV system (2.7 kW facing south, 1.3 kW facing west)

PVRES Home Features Control Home FeaturesWhite reflective roof with R-30 ceiling insulation

Gray/brown asphalt shingle roof, R-30 ceiling insulation

Exterior insulation over concrete block system (R-10)

R-4 wall insulation on interirorof concrete block walls

Advanced solar control double-glazed windows

Single glazed windows with aluminum frames

Down-sized SEER 14.4 variable speed AC

4-ton Trane heat pump (SEER = 10; HSFP = 7)

Field-verified cooling coil air flowLow friction loss and sealed duct system within the conditioned space

R-6 ducts located in attic

Programmable thermostatHigh efficiency refrigerator Standard appliances (electric

range, refrigerator and electric dryer)

High efficiency compactFluorescent lighting

Standard incandescent lighting (30 recessed can lights)

Source: Parker D., Very low energy homes in the United States: Perspectives on performance from measured data, Energy and Buildings, Volume 41, Issue 5, May 2009, Pages 512-520,

PVRES, Florida (Cont.)

Thermal and visible images of west-facing windows and shadows in the afternoonBaseline home PVRES home

Source: Parker et al., Field Evaluation of Efficient Building Technology with Photovoltaic Power Production in New Florida Residential Housing, Florida Solar Energy Center, FSEC-CR-1044-98


Thermal and visible images of west-facing windows and shadows in the afternoon



Thermal images of air being drawn from the attic to the AHU in the baseline house (center). The interior duct system in the PVRES shows no problem



CaseDescripti

onAHU

statusAir

Changes Per Hour

InteriorTemp (°F)

Exterior Temp (°F)

Wind Speed (m/s)

Baseline Off 0.131 76 90.6 5.2Baseline On 0.349 76 89.9 8.0PVRES Off 0.085 74 86.5 9.5PVRES on 0.131 74 85.6 10.2


PVRES, Florida (Cont.)• From April-August, averaged 15.66 kWh

delivered to the utility grid every day• The PVRES consumed averaged 22.0

kWh/day• The PV system produced 71% of the daily

electricity required for the building operation• During daytime hours the net impact on the

grid is nearly zero• During evening hours all power required

came from the utility


April 15 16 17 18 19 20House thermal performance when unconditioned ( top baseline; bottom PVRES)

PVRES, Florida (Cont.)Component Description Cost ($) Savings

kWh ($)Simple payback

(Years)Advanced windows $4,266 1,610 ($129) 33White tile roof $10,829 1,342 ($107) 101R-10 walls $11,500 307($25) 460Wider overhang $1,882 537 ($43) 44Interior duct system $950 1,150 ($80) 12High efficiency AC $1,263 2,376 ($190) 7Efficient Lighting $525 1,479 ($118) 4High Efficiency refrigerator $298 388 ($31) 10Solar water heater $2,989 2,097 ($123) 24Utility integrated PV system

40,000 5,600 ($448) 89Preliminary economics of efficiency measures


NZE House in Stow, MA

Source: Engelmann, P., Roth, K., 2011, IEQ/IAQ and Energy Performance of Very Low-Energy Homes, Summer 2011 Residential Ener. Eff. Tech. Update Meeting, Aug. 2011. web source: http://apps1.eere.energy.gov/buildings/publications/pdfs/building_america/ns/eemtg082011_c4_very_lowe_homes.pdf

Energy production and consumption

End-energy usage breakdown

Source: Engelmann, P., Roth, K., 2011, IEQ/IAQ and Energy Performance of Very Low-Energy Homes, Summer 2011 Residential Ener. Eff. Tech. Update Meeting, Aug. 2011. web source: http://apps1.eere.energy.gov/buildings/publications/pdfs/building_america/ns/eemtg082011_c4_very_lowe_homes.pdf

NZE House in Stow, MA (cont.)

NZE House in Lebanon, NJ

ElementsBldg. Orientation True south, Passive

solar heating, daylightingLayout Open planConditioned Area 4200 sf (390 sm)Framing 2 by 4 at 16” O.C.Type Single-family detachedMaterials Douglas fir; Southern

Pine

SpecificationsSlab Floors R-35 (6 m2K/W)Foundation Walls R-35 (6 m2K/W)Basement Ceiling NoneAbove Grade Walls R-35 (6 m2K/W)Roof R-35 (6 m2K/W)Window R-10 (2 m2K/W)Relative Humidity 40-50%Infiltration Rate 5.0 ACH@50Pa

4 bedrooms, 2.5 baths, living room, dining room, kitchen, laundry room and a basement

Source: Hoque, S., 2010, Net zero energy homes: an evaluation of two homes in the northwestern United States, Journal of Green Building, Vol. 5 (2), pp. 79-90.

Energy SystemsEnergy ConsumptionHeating Air(AHU) + Radiant

(Solar Thermal)AC NoneWater Heating Solar ThermalVentilation NatureEnergy GenerationPassive Solar Heating

YesPV 9.8 kWWind NoneSolar Thermal Yes


NZE House in Lebanon, NJ (cont.)

NZE House in Charlotte, VT


ElementsBldg. Orientation True south, daylightingLayout Open planConditioned Area 2800 sq. ft. (260 m2)Framing 2 by 6 at 24” O.C.Type Single-family detachedMaterials FSC Certified wood

Local crafted concrete countertopsLocal sustainable harvested mapleFlooring & hardwoodsCellulose & denim insulationReclaimed fir columns

LEED certification LEED Platinum

SpecificationsSlab Floors NoneFoundation Walls R-19 (3 m2K/W)Basement Ceiling R-19 (3 m2K/W)Above Grade Walls R-40 (7 m2K/W)Roof R-56 (10 m2K/W)Windows R-10 (2 m2K/W)Relative Humidity 40-50%Infiltration Rate 2.0 ACH@50Pa

Energy SystemsEnergy ConsumptionHeating Radiant (Ground source

HP)AC NoneWater Heating Instantaneous (on-

demand)Ventilation HRVEnergy GenerationPassive Solar Heating

No

PV NoneWind 10 kWSolar Thermal Hybrid (GHP + on-

demand)


NZE House in Charlotte, VT (cont.)

EcoTerra HouseTM, Canada

http://sbrn.solarbuildings.ca/main.php?l=e&d=1&i=3&t=demoprojects

• Built in November, 2007• Two-story detached home, 234

m2• 3 kW BIPV/Thermal system on a

55 m2 south-facing roof (22 amorphous silicon 135W cells)

• 10 kW solar thermal generation• Two-stage Geothermal heat

pumpSource: Noguchi et al., 2008, Net zero energy homes of the future: a case study of the EcoTerraTM House in Canada, Presented at the Renewable Energy Congress, Glasgow, Scotland, July 19-25, 2008

EcoTerra HouseTM, Canada

Source: Noguchi et al., 2008, Net zero energy homes of the future: a case study of the EcoTerraTM House in Canada, Presented at the Renewable Energy Congress, Glasgow, Scotland, July 19-25, 2008

Non-Residential Examples: Lewis Center, Ohio

Source: http://www.oberlin.edu/archive/resources/photoguide/lewis_center.html• Two-story, 13,600 sq. ft.• Renovation completed in

2000• Building includes

classrooms, offices, an auditorium, an atrium

• 60-kW PV system covers the entire roof (690 85-Watt single crystalline modules) Zone-decentralized heating and cooling system

For classrooms, offices and corridors For auditorium

Source: Pless and Torcellini, 2004, Energy Performance Evaluation of an Educational Facility: The Adam Joseph Lewis Center for Environmental Studies, Oberlin College, Oberlin, Ohio, NREL Technical Report, NREL/TP-550-33180

Lewis Center, Ohio (Cont.)

Source: Pless and Torcellini, 2004, Energy Performance Evaluation of an Educational Facility: The Adam Joseph Lewis Center for Environmental Studies, Oberlin College, Oberlin, Ohio, NREL Technical Report, NREL/TP-550-33180

Building electric system plan and DAQ meter locations

Average daily performance, March 1, 2001 through Feb. 28, 2002

The Science House, Minnesota

Source: http://leedresource.wordpress.com/2012/02/11/zero-energy-buildings-myth-or-must

• New construction completed in 2003

• Single-story, 1530 sq. ft.• Occupied by 2 people; 795

visitors per week• Wood-frame structure• 8.8 kW PV system• Project cost: $650,000

1) Science house changes from energy user to energy producer 2) new equipment plugged into the Science House 3) Science House goes into unoccupied mode, equipment except for card reader is turned off 4) Science House becomes net energy user

Weekly Energy Balance in 2005

ORNL Office Building 3156

• Two-story, 6,940 sq. ft.• Last renovation completed

in 2009• 31 occupants; 23 offices +

1 conference room• Commercial office, campus• 51-kW PV system• High efficiency packaged

terminal heat pumps• Total project cost (land

excluded): $660,000

Renovation Highlights:• R-23 roof insulation with a high-

performance reflective membrane added

• High efficacy T8 lighting using electronic ballasts

• Occupancy sensors to control both HVAC and lighting

• A energy consumption monitoring system to better understand energy use profile of the building

http://femp.buildinggreen.com/energy.cfm?ProjectID=1585

NIST nZEH Test Facility

• Located at Gaithersburg, MD• Designed to achieve LEED platinum• To demonstrate a residence, typical in DC area, can achieve nZEH• To provide “real world” field data for validation and improvement

http://www.nist.gov/el/building_environment/heattrans/upload/netzerofinal.pdf

NIST nZEH Test Facility-its Unique Features

http://www.nist.gov/el/building_environment/heattrans/upload/netzerofinal.pdf

NZEB Database from DOELEED PlatinumLEED Platinum

LEED Platinum

LEED Platinum• Source: http://zeb.buildinggreen.com/• 10 projects from DOE Zero Energy Buildings database• Building types include: commercial offices, recreation, education/lab,

residential, interpretive center and retail• Some of them are also LEED platinum rating and HERS level 0

Technologies Available for NZEB

Source: http://www.ecofuturesbuilding.com/learn-zero/what-is-zero-net-energy/

Summary of the Main Technologies for NZEB

Proven technologies Still developing technologies

Technologies on thehorizon

Thermal insulation

Low conductivity materials; Reflective materials

Reflective roofs; green roofs; exploring new materials for thermal insulation

Smart reflective roofs; cool colored paints (with IR reflective pigments); nanomaterials for thermal insulation; highly insulation façade systems

Windows Multi-layer windows;Low-e glazing; gas filled air gaps; thermal break frames

Glazings with dynamic properties(e.g. electrochromics)

BIPV glazings; solar glazing; solar curtain walls

Lighting CFL; LED; daylight harvest through transparent envelope

CFL; LED;intelligent, dynamic and/or light-redirecting facades with automated lighting controls

Intelligent naturaldaylighting distributing systems


Summary of the Main Technologies for NZEBProven technologies Still developing

technologiesTechnologies on the horizon

Heating and cooling equipment

Condensing gas boilers; biomass boilers; high EER chillers and heat pumps (ground and air source)

Micro CHP Solar CHP; thermally activated HP; TE cooling; frostless HP; distributed refrigeration/water-source HP

Ventilation Mixed mode natural and mechanical with heat recovery (HR); nightlycooling; stack effect ventilation

Hybrid ventilation systems with automatic controls; displacement ventilation

Heat recovery windows; personalized ventilation

Renewable technologies

Thermal solar; biomass heating; PV systems; PV thermal solar systems; air solar collectors

PV systems (increased efficiency); PV thermal solar systems

BIPV systems, wind turbines (WT) and micro WT

Building energy management systems

Sensors; energy control(zone heating and cooling) and monitoring systems

Monitoring and control systems running on IP communication infrastructure

Improved management systems with grid/consumer supply-demand integration


ZEB Renewable Energy OptionsOption Number (Hierarchy)

ZEB Supply-Side Options Examples

0 Reduce site energy use low-energy building technologies

Daylighting, high-eff. HVAC equip., natural ventilation, evaporative cooling…

On-site Supply Options1 Use renewable energy sources

within the building’s footprintPV, solar hot water, and wind located on the building

2 Use renewable energy sources available at the site

PV, solar hot water, low-impact hydro, and wind located on-site, but not on the building

Off-site Supply Options3 Use renewable energy sources

available off site to generate energy on site

Biomass, wood pellets, ethanol…

4 Purchase off-site renewable energy sources

Utility-based wind, PV, emissions credits, other “green” purchasing options

Highly preferred

preferred

Source: Torcellini et al., 2006, Zero energy buildings: a critical look at the definition, ACEEE Summer Study, Aug. 14-18, Pacific Gove, CA

Technology Penetration

Data is collected based on a database of 60 net zero energy/ net zero energy capable commercial buildings

Source: Getting to zero 2012 status update: a first look at the costs and features of zero energy commercial buildings, New Building Institute research report, March 2012

Solar Curtain Wall

Source: Case study: solar curtain wall, Konarka, Aug. 2011

Building Integrated Wind Turbines

Source: http://www.mymodernmet.com/profiles/blogs/what-big-wind-turbines-you; http://sustainability.yale.edu/sites/default/files/bec3.jpg

Wind turbines in World Trade Center, Bahrain Micro wind turbines in Yale Univ.

Cost/Performance Curve

Source: Anderson R. and Roberts D., Maximizing Residential Energy Savings: Net Zero Energy Home Technology Pathways, NREL/TP-550-44547

Previous ThermCom Development

47

48

Max Tech and Beyond: Ultra-Low Energy Use Appliance Design Competition for 2011-2012

SSLCAC Design Overview

Radiative Heat Exchanger: Cooling Wall49

Other examples

Net Zero Homes

Sep. 2010 R. Radermacher

51 Net Zero home - Ft. Worth, Texas

Net Zero Homes


52Net Zero “Beach House” - California

Net Zero Homes


53Net Zero - Chicago

Net Zero Homes


54Net Zero – Staplehurst, England

Net Zero Homes


55

“Cannon Beach Residence” Oregon coast

Net Zero Homes• LEED Platinum• Currently holds highest rating for a Net Zero residence in the US• Produces 40% more energy than it consumes


56Yannell Residence, Illinois

Belgian NZE station at Antartica

Sustainable Homes