Net-Zero, Net-Zero Ready, Carbon Neutral Buildings: What are they? - - PowerPoint PPT Presentation

Net-Zero, Net-Zero Ready, Carbon Neutral Buildings: What are they? Why build one? And how?

NRG Systems Dartt House and Maclay Architects Office Bennington Superior Court and State Office Building

Economy, Energy, Environment, Equity & Population

Global Challenges, Our Built Environment & Survival

Workplace in Transition

Energy At the Core

Population

ENERGY

Climate Change Ecosystem Degredation Lifestyle

Peak Oil – The Energy Transition

Historical Fuel Oil price / barrel

(in 2012 dollars)

The Energy Transition – Renewable Energy Solar Plateau

Cost per unit of fuel when the cost of heat from a heat pump powered by PV is equivalent –

(in New England) with efficiencies of heat sources incorporated

Electric (kWh) Propane (gal) Oil (gal) Natural gas (therm) $/MMBtu $0.14 $3.76 $5.58 $4.10 $41.02 *Current cost of electricity from PV $0.12 $3.84 $5.71 $4.20 $35.67 *Plateau for heating sources $0.06 $1.92 $2.85 $2.10 $17.83 *Current cost of heat from Heat Pump and PV $0.04 $1.26 $1.88 $1.38 $11.72 *Current Cost including 30% federal tax credit

Net-Zero: The New / Rediscovered Paradigm

Key Questions “The world we have created today as a result of our thinking thus far has problems that cannot be solved by thinking the way we thought when we created them.”

• Albert Einstein

Farming/Renewable Coal Oil

Evolution of Energy & Lifestyle

1800 1900 2000 Renewable Coal Oil Renewable & Other

What are Net-Zero Buildings?

Net-Zero Buildings produce more energy than they consume on an annual basis

• Building
• Site
• Source
• Net-metered
• Equivalent
• Offsets

NREL’s Research Support Facility Golden, CO 220,000 sf - 35.4 EUI 100% renewable from on site PV

Is this a Net-Zero Building?

The Three Elements of a Net-Zero Building

• Low Energy Consumption
• Efficient Simplified Systems
• Renewable Energy

How do we get low energy consumption?

• Integrated Building Design
• Massing
• E-W orientation
• Daylight
• Healthy Workplace

• Energy Conserving Building Envelope
• Walls, Roof, Foundation,

air movement How do we get low energy consumption?

• Energy Modeling/Metrics

(10-25 kBtu/sf-yr for offices)

• Programming
• Design
• Commissioning
• Construction

How do we get low energy consumption?

What are simplified systems?

• Right Size Equipment
• Minimize Distribution
• High Performance Mechanical Systems (ASHP)
• Controls

What are Renewables?

• Usually Solar Photovoltaics
• Own
• Lease
• Power Purchase Agreement

What is a Net-Zero Ready Building?

• A Net-Zero building without Renewables

Bennington Superior Court and State Office Building

What is a Carbon Neutral Building?

• A Net-Zero Building with biomass for renewable energy

Private Residence, Putney, VT NRG Systems, Hinesburg, VT Aldo Leopold Legacy Center, Baraboo, WI

NRG Systems

OWNER Wind NRG Partners, LLC DESIGN TEAM Architects – Maclay Architects Mechanical , Electrical & Fire Protection – Salem Engineering / LN Consulting Structural & Civil – Engineering Ventures Preconstruction Services – Erickson Consulting Energy Consultant – Energy Balance Landscape - TJ Boyle and Associates Lighting Design – Naomi Miller Lighting Design Fire Protection - Chase Engineering, PC CONSTRUCTION TEAM General Contractor – Breadloaf Construction / HP Cummings Construction

NRG Systems

BUILDING TYPE: Model Renewable-Powered Workplace SCOPE: Two new buildings and masterplan PROJECT SIZE: Phase 46,500 SF, 31,000 SF PROJECT COST: $5,000,000, $6,500,00 COST/SQFT: $107/SF, $212/SF ENERGY INTENSITY: 23 kBtu/SF-yr, 19 kBtu/SF-yr PERCENT RENEWABLE: 89%, 95% AIR INFILTRATION: 0.18 cfm50/SF, 0.092 cfm50/SF NATURAL: 0.08 ACH, winter, 0.05 ACH, winter LEED RATING: LEED-NB Gold both buildings

Integrated Environmental Design & Systems

Energy conservation Daylighting Renewable energy usage Pond for cooling Storm water management

Building 2

Integrated Environmental Design & Systems

Pond – Cooling, Storm Water Retention, Recreation

Entrance, Cafe Terrace & Board Room Balcony

View towards fireplace & hearth from café Warehouse Connection

Building 1 – Central Heart

Street & Office

Energy Conservation

Phase 2 Building Improvements

Enhanced energy conservation Simplified mechanical systems Hybrid steel/wood structure

View into the café Library and Floor Art on 2nd Floor

Building 2 – Central Heart

Bennington Courthouse:

Project Goals: Healthy Building Excellent Energy Performance

Bennington Courthouse:

BUILDING TYPE: Healthy Building Renovation SCOPE: Renovation & Addition PROJECT SIZE: Phase 65,000 sf TOTAL CONSTURCTION COST: $13,500,000 (anticipated) COST/SQFT: $208/sq ft ENERGY INTENSITY (existing building): 110 kbtu/sf ENERGY INTENSITY (modeled): 23 kbtu/sf

Pre-Existing Conditions

• Employee complaints
• Unoccupied building
• IAQ problems
• Poor building envelope

(moisture & energy)

Site Plan

EXISTING BUILDING FOOTPRINT

Floor Slab Details

EXISTING BUILDING NEW CONSTRUCTION

TOTAL ENERGY USE ALL SOURCES, existing building fossil fuel converted to kWh Note: disaggregation of existing electric use very approximate

Bennington Court and Offices Actual Existing and Modeled Proposed

• 500,000

1,000,000 1,500,000 2,000,000 2,500,000 Existing New

kWh

Electric other lighting heating cooling EUI =110 kBtu/sf-yr EUI = 25.6 kBtu/sf-yr

Building Performance

July 2012-June 2013 = 459,052 kWh and 1,084 gallons of propane Total = 1,664,715 kBtu/year EUI = 25.6 kBtu/sf-yr

Financial Analysis Net-Zero Ready building

• $370,000 additional capital cost
• $49,000/yr projected energy savings

3 Building Options: 20 year capital and operation costs Net-Zero Ready 20 year cash flow

• capital cost (green) or financing
• ption (red)

Simple Payback: 7.6 years ROI: 13% Net Present Value*: $2,432,583 Internal Rate of Return*: 6.2% *with 3% annual fuel escalation rate

Mixed Use, Historic, Net-Zero, Net-Metered Property:

A Case Study from Waitsfield

Project Site Context

Historic Waitsfield Village Warren, VT residence Mad River Valley

Waitsfield Context

Open trusses, open office = daylighting Laptop computers Light guiding blinds Ceiling fans and efficient light fixtures

Simplify / Minimize System Loads

Minisplits/heat pumps Additionally:

• ERV’s
• Distribution –radiant and air

Envelope Upgrades and Load Reduction

Install Renewables

2 kW PV NRG tracker

Office purchased with tax credits

17.55 kW PV Alteris Carport Office financed plus GMP and

USDA grants

20 kW PV All Earth Renewables tracker

Power Purchase Agreement

Verification and Documentation

Consumption: Office: 97,948 kBtu = 28,707 kWh Warren House: 59,021 kBtu = 17,298 kWh Apartments (1&2) 42,240 kBtu = 12,208 kWh 199,209 kBtu = 58,213 kWh PV Production: Watisfield site: 63,712 kBtu =18,673 kWh Warren site: 83,966 kBtu = 24,609 kWh 147,678 kBtu = 43,282 kWh Net Energy used: 51,531 kBtu = 14,931 kWh

(Oct 2012-September 2013 data)

Office EUI: 38 kBtu/sf Apartment building EUI: 19 kBtu/sf Warren House EUI: 17 kBtu/sf

Outcome

• Rental income
• From: 1 apartment - $1,200/month
• To: 2 apartments -$1,900/ month
• Net-Zero Architecture Office
• Through on and off site renewables
• Net-Metered mixed use complex
• Off site additional renewables

Waitsfield and Moretown Town Offices

Thank You and Questions?