The Greening of the Rooftop Module 8 Green Roofing: Clean Energy Roofs

Photo-Voltaic Daylighting Wind Clean Energy Roofs Clean Energy Roof Options

Clean Energy Roofs Photo-Voltaic (PV) Roofs

Target Store Stockton, CA Shiseido Windsor, NJ PV Roofs Clean Energy Generation

PV Roofs Components PV Modules Balance of System (BOS) Services

PV Roofs PV Modules MonocrystallinePolycrystallineAmorphous

PV Roofs PV Modules Technology Monocrystalline Polycrystalline Amorphous Industry Goal Efficiency 15-18% 13-15% 5-8% 25% Notes: Highest market share, highest cost Lower cost, gaining in efficiency Lower cost, leading thin film candidate Where PV manufacturers want to be by 2015 Source:

PV Roofs Balance of System (B.O.S.) Key Components –Mounting Systems –Wiring & Connectors –Controllers (Energy Management) –Inverters (DC to AC) –Batteries (Reserve Energy) –Load Connection (Building / Grid) Account for over 30% of total PV material costs

PV Roofs Services Key Components –Design (Electrical, Structural, Architectural) –Financing (Power Purchase Agreements, Underwriting) –Legal (Special Entities, Operating Contracts) –Installation (Roofing, PV System, Electrical) –Operation (Monitoring, Power Billing, Incentive Management) –Maintenance (Inspection, Repair) Account for over 30% of total PV installed costs Typically provided by a System Integrator

PV Roofs Residential / Commercial Systems Residential Systems –From 1.5 KW to 6 KW total output –From $15,000 to $60,000 installed cost –Frequently not tied directly to the grid –Usually purchased and financed by the homeowner Commercial Systems –From 0.5 MW to 2 MW total output –From $3.25 MM to $13 MM installed cost –Frequently tied directly to the grid –Usually purchased and financed by a “Special Purpose Entity”

PV Roofs Typical Residential PV System (w/o Net Metering) 20 Amp. Controller 8 X 60 Wp Modules 6 X 12v 100Ah Batteries 1500 W Inverter Separate Distribution Panel 100 A. Fuse Loads

Module Array Combiner Box DC Disconnect Inverter DC AC Meter AC Disconnect Main Panel PV Roofs Typical Commercial PV System ( w/ Net Metering) Combiner Box Module Array Controller To Grid

PV Roofs PV Roof System Types Non-Integrated –Mounted on framing over roof –Similar to other roof-mounted equipment Integrated –Physically incorporated into the roof system –Performing some roofing function along with power generation

PV Roofs Non-Integrated PV Roof Systems Benefits: Can be tilted to align with sun’s angle Wiring can be placed above roof for easy access Long performance track record with conventional silicon modules Limitations: Anchorage may require extensive penetration of roof Wind uplift resistance may be a concern May be difficult to maintain and service the underlying roof

PV Roofs Integrated PV Roof Systems Thin-Film Laminated to Single-Ply Self-Ballasting and Insulating Solar Paver Thin-Film Laminated to Standing Seam Metal Thin-Film Solar Shingles

PV Roofs Integrated PV Roof Systems Benefits: Reduced material costs for framing Reduced labor costs Limitations: Typically restricted to angle of roof – may compromise output Wiring may penetrate the roof membrane Roof traffic may damage panels Heat build-up may damage underlying roof membrane The thin films frequently used in integrated PV have a relatively short performance record compared to conventional solar modules

PV Roofs What are the Economics? PV manufacturing costs appear to be moving down, especially thin-film Central power costs are increasing, especially peak demand energy Subsidies and incentives for PV appear to be increasing, especially at the state and local level Currently, PV roofing is not economical across the United States, but…

PV Roofs What are the Economics? The Supply Chain The Operating Chain The Financial Incentives To understand PV economics, it is necessary to look at ….

PV Module Manufacturer Silicon Wafer Manufacturer System Integrator Inverter Manufacturer Connector Manufacturer Mounting Manufacturer Control Manufacturer Battery Manufacturer System Installer PV Roofs Supply Chain Project Financier $ COMPLETED PROJECT Investors Host Building Owner Building Operator Utility

System Integrator Service Contractor PV Roofs Operating Chain $ COMPLETED PROJECT Investors Depreciation Operating Net Tax Credits Rebates Host $ Power Purchase Government, Utility $ Tax Credits Rebates $ Operating Exp. Service Repair

Federal Incentives (Energy Policy Act of 2005) –30% Investment Tax Credit –5-Year Accelerated Depreciation –Additional Tax Deductions if Combined with Energy Efficiency Improvements State & Local Incentives (Varies Widely) –Government & Utility Rebates –Tax Credits –Fee Reductions / Exemptions –Loans –Grants PV Roofs Financial Incentives See Module 10 for Additional Information

O&M Module $3.30 Inverter $0.35 Racking $0.18 Overhead $0.25 Installation $0.60 Integrator Mark-up $1.51 $6.54/W Installed Price Incentives Project Costs $0.35 Federal 30% Investment Tax Credit $0.82/W Net Cost Source: StrateGen Analysis. Assumes 8% discount rate and 20 year project lifetime for a typical rack-mounted 1 MW installation in California. Lifetime Cost Energy Savings $1.57/W Accelerated Depreciation $4.37/W$0.21/W California Performance- Based Incentives 20 Year Total Energy Savings PV Cost Example: Typical Commercial Installation: California Current incentives are almost 3 times total energy savings!

PV Cost Example: Typical Commercial Installation: California Source: StrateGen Analysis. Assumes 20 year project lifetime for a typical rack- mounted 1 MW installation in California. 1MW Installation: Las Angeles, CA

PV Cost Example: Typical Residential Installation: Arizona Source: American Solar Electric ( 10 KW Installation: Phoenix, AZ

Benefits:Current Limitations: Clean energy generated Peak energy demands reduced PV Roofs Overall Benefits & Limitations Significant incentives required to achieve “grid parity” Financing is very complicated and expensive Maintenance: Increasing roof traffic. Leak detection may be difficult Durability: Underlying roof system must be designed to meet or exceed PV system service life. Design & Commissioning: How is system performance validated? Accountability: Who will be accountable for the integrated system?

Clean Energy Roofs Daylighting West Valley Library San Jose, CA

Passive Systems Active Systems Hybrid Systems Clean Energy Roofs Daylighting

Passive Systems Passive Systems Capture, Reflect & Direct Daylight

Active Systems Follow the Sun to Maximize Sunlight Capture Daylighting Active Systems

Daylighting Hybrid Systems Hybrid Systems Combine Solar and Electric Lighting in an Integrated Package

Benefits:Current Limitations: High return on investment Excellent product to integrate into a roof replacement Many states and utilities have incentive programs Daylighting Benefits & Limitations Design is complex: Must consider heat loss / heat gain along with lighting savings Commissioning: How is system performance validated? Durability of newer active systems – little long-term performance data Accountability for hybrid systems: Who will be accountable for the integrated system?

Clean Energy Roofs Wind Mercy Lakefront SRO Chicago, IL Staples Distribution Center Monrovia, CA Adventure Aquarium Camden, NJ

Roof Wind Systems Vertical Turbines Single Vertical Turbine Multiple Vertical Turbine

Roof Wind Systems Horizontal Turbines Single Horizontal Turbine Multiple Horizontal Turbines Ganged Horizontal Turbines

Roof Wind Systems Benefits & Limitations Benefits: Current Limitations: Higher return on investment than PV New multiple arrays can generate significant power Easily integrated into rooftop PV systems Many states and utilities have incentive programs Relatively low total power capability May produce vibrations that may adversely affect roofing system Design & commissioning: How is system performance validated? Durability of newer multiple systems – little long- term performance data Who will be accountable for the integrated system?

Interstate Renewable Energy Council U.S. Department of Energy Solar Energies Technology Program Whole Building Design Guide: Building- Integrated Photovoltaics (BIPV) Daylighting Collaborative Rooftop Energy Systems Find Out More… WBDG WHOLE BUILDING DESIGN GUIDE