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Pacific Energy Center

851 Howard St.

San Francisco, CA 94103

Basics of Photovoltaic (PV) Systemsfor Grid-Tied Applications

Courtesy of DOE/NREL

instructor

Pete Shoemaker

Energy Training Center

1129 Enterprise St.

Stockton, CA 95204

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Basics of Photovoltaic (PV) Systems

for Grid-Tied Applications

Material in this presentation is protected by Copyright law.Reproduction, display, or distribution in print or electronicformats without written permission of rights holders is

prohibited.

Disclaimer: The information in this document is believed to accuratelydescribe the technologies described herein and are meant to clarify andillustrate typical situations, which must be appropriately adapted toindividual circumstances. These materials were prepared to be used in

conjunction with a free, educational program and are not intended toprovide legal advice or establish legal standards of reasonablebehavior. Neither Pacific Gas and Electric Company (PG&E) nor anyof its employees and agents: (1) makes any written or oral warranty,expressed or implied, including, but not limited to, those concerningmerchantability or fitness for a particular purpose; (2) assumes any

legal liability or responsibility for the accuracy or completeness of anyinformation, apparatus, product, process, method, or policy containedherein; or (3) represents that its use would not infringe any privatelyowned rights, including, but not limited to, patents, trademarks, orcopyrights.

Some images displayed may not be in the printed booklet because of copyright restrictions.

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www.pge.com/solarPG&E Solar Information

www.pge.com/pec

Pacific Energy Center (San Francisco)

http://www.pge.com/myhome/edusafety/workshopstraining/stockton

Energy Training Center (Stockton)

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Pete ShoemakerPacific Energy Center851 Howard St.


(415) 973-8850

[email protected]

Contact Information

Some images displayed may not be in the printed booklet because of copyright restrictions.

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5

Agenda

1. Big picture: Team Cali fornia

2. Electricity Fundamentals3. PV Technology

4. Feasibility

5. Finances

6. Sales & Instal lation Process

7. Jobs Overview and Future Trends

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6Pacific Energy CenterSan Francisco

One Minute Summary

Buy your own power plant

The basic economics are

just like the rent vs. buyof purchasing a home.

Your hom e needs

electricity

Sameelectricity

Courtesy of DOE/NREL Source: Pete Shoemaker

CURRENT POSSIBLE

Rent a portion of utility grid output

RENT OWN

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The Big Picture:

Team California

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The California Regulated Utility

Financial Structure

How the utili ties make money,

and why they can support energy

efficiency and conservation.

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Cali fornias regulated uti l i ties cover mostof the state.

PG&ESouthern California

Edison (SCE)

San Diego Gas &Electric (SDG&E)

Southern CaliforniaGas (SoCalGas)

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They are essentially monopolies in theirrespective territories, and so need to beregulated.

CPUC

The California Public Util ities Commission isthe regulatory body.

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30 years ago, the uti li ties made money like mostbusinesses: on profits from sales.

The more energy they sold, the more profitthey made.

Energy Sales

Profits

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Also 30 years ago, Californias power

consumption was rising rapidly, along with therest of the country.

Per-capita powerconsumption.

U.S.

California

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Projecting this into the future made people

realize that it was not sustainable, and thatsomething needed to be done.

Very high utility bills

Many more new power plants

Serious environmental consequences

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We needed to lower peoples energy usage,

but how?

The utili ty companies had to be involved, buthow could you require them to encourageless energy usage, since their profits andbusiness model depended on more sales?

Conclusion:

The utili ty financial structure must change.

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DECOUPLINGSeparating profits from sales.

Energy Sales

Profits

Energy Sales Profits

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Since 1978 (gas) and 1982 (electricity)Californias regulated utili ties have made

profits on INVESTMENTS, not SALES.

These investments are directed by the CPUCand include energy efficiency andconservation.

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Example of EE investment and target:

1.The CPUC authorizes PG&E to spend themoney to give away 1,000,000 CFLs.

2.The target over 3 years is to reduce electricconsumption [xx] mWh.

3.If PG&E makes the target they can set ratesso that they earn [x]% for theirshareholders.

4.If they exceed the target they can earnmore, if they miss the target they earn lessor even get penalized.

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California uti li ties have NO incentive to

increase energy usage.

They DO have mandates and incentives forenergy effic iency, conservation, and

renewables.

The result?Cali fornia, and PG&E, is the leader in

energy eff iciency and renewablegeneration.

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Solar Electric Trends

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Source: U.S. Energy Information Administration,Electric Power Monthly

Geothermal 4%

Wind3%

Small Hydro 3%Solar

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Cou rtesy PG&E

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Cou rtesy PG&E

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Cou rtesy PG&E

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Cali fornia Public Uti l i ties Commission

(CPUC) Loading OrderHow we fill in new supply in California

1. Energy Efficiency/Demand response2. Renewables

3. Distributed Generation (such as CHP)

4. Conventional efficient fossil generation

The Big Picture

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Total energy consumed = 40.67

Over 2/3 of the energy is wasted.

Delivered for end use = 13.21 (32%)

U.S. Electricity Generation 2008

Source: Energy Information Adminis tration / Annual Energy Rev iew 2008

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Energy Conservation

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3 times the value!

Energy Conservation

Thats leverage!

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PG&E Portfolio Solution

ReduceEnergy

Use

RenewablePower

Supply

ClimateSmart

PartnershipEducation

Outreach

1) Reduce consumption as

much as possible.

2) Get thegreenestpower you

can.3) Offset anyremainingcarbonemissions.

PG&E as a Partner and Solutions Provider

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Electricity Fundamentals

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Waterpressure

Output

(work done)

Amount of flow

Elec.

pressure

Amount of flow

Output

Volts

Amps

Watts

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Watt (W) = Basic unit of PowerIn generator: Capacity to do work

In appliance (load): Requirement for work to be done

Electrical terms:Amps x Volts = Watts

5A x 12V = 60 W 0.5A x 120V = 60 W

Kilowatt (kW), Megawatt (MW)

1 kW = 1,000 Watts2.5 kW = 2,500 Watts1 MW = 1,000,000 Watts500 MW = 500,000,000 Watts


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Power over time = Work

Watts over time = Watt-hours (Wh)

1 sec.

Instantaneouspower: 20 W

1 hourPower overtime: 20 Wh

Power x Time

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Watt-hour (Wh) x 1000 = Kilowatt-hour (kWh)

In a generator:

How many kWh are produced when a 5 kW PV systemoperates at ful l power for 6 hours? 30 kWh

In a load:

How many kWh are used when a 200 W bulb shines for10 hours? 2000 Wh or 2 kWh

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Voltage and Current

Area of rectangle = total power (watts)

Same area = same power, just in different form.

Amps

Volts

Amps

Volts

Volts x Amps = Watts

Watts

Watts

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Voltage and Current

The larger the current, the larger the wire needed tomake it flow efficiently (more pipe ).

Copper wire is expensive.Using higher voltage allows the same amount of powerto be transmitted with lower current, saving money.

20 amps

2 amps

T f El i l C

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DC = Direct current

*PV panels produce DC*Batteries only store DC

AC = Alternating current*Utility Power

Types of Electrical Current

Voltage x Time

1/60 of a second

60 Hertz in U.S.(60 cycles / second)

+V

0V

-V

AC power can be stepped up and down in voltage mucheasier than DC power, therefore most power is AC.

Th El t i G id

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The Electric Grid

Source: PG&E

Th El t i G id

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Electricity can be transported at the speed of light,therefore any point can be said to be connected toall others.

This network is called the GRID and is nation-wide.

Source: NRELSource: NPRhttp://ww w .npr.org/templates/story/story.php?storyId=110997398

The Electric Grid

Th El t i G id

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Generation: Creating electricity.

Transmission: Moving it in bulk fromgenerators to distribution centers.

Distribution: Bringing it from centers(sub-stations) to individual homes andbusinesses.

There are three main components of the grid:

Source: NREL

The Electric Grid

Th El t i G id

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Generation

10,000 V (10 kV)

Above 50,000 V (69 kV up to 765 kV)

TransmissionStepup

Stepdown

Sub-station

Distribution

12,000 V (12 kV)

Stepdown

120V 240V

Home480V

Business

Source: NREL

The Electric Grid

Grid Terms

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Grid Terms

Supply side

Generation

Demand side

Usage (load)

Source: NREL

Grid Terms

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Baseload: Minimum amount of power that isalways needed

Seasonal load: Increase in demand inspecific times of the year.

Peak load: Maximum amount needed.

Capacity: Total power that the system can

provide.

Grid Terms

Grid Terms

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PG&E 2006 Annual Usage

Baseload

Grid Terms

Grid Terms

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Seasonal load

Grid Terms

Grid Terms

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Peak load

Grid Terms

Grid Terms

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Highest demand occurs on only a few hours in the year

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

1 501 1001 1501 2001 2501 3001 3501 4001 4501 5001 5501 6001 6501 7001 7501 8001 8501

Time

MWs

The top 50 Hoursrepresent 0.6% of thetotal hours in a year

Load Duration CurveLoad Duration Curve

Grid Terms

Grid Terms

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Capacity

Grid Terms

Grid Terms

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Unused Capacity

Grid Terms

Grid Terms

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Spread out the demand and you

can lower the capacity need.

Grid Terms

Grid Terms

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Demand Management or

Demand-side Management

Load-shifting

How do you get people to use less powerduring peak times and more during off-peak?

Grid Terms

Demand Management Strategies

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1. Reduce overall load. Energy efficiency, conservation

2. Inform people so they can cooperatevoluntarily. Publicity, Flex Your Power alerts

3. Create the ability to remotely turn offcertain appliances. Smart AC, smart meters, etc.

4. Charge more for peak usage. Time-of-Use rates, Peak-Time pric ing

and others.

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PV Technology

Different types of Solar

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Light energyPhotovol taic (PV)

Electricity produced directly from light

Different types of Solar

Heat energy

Concentrated Solar Power (CSP)

Electricity produced by steam

Solar Pool Heating

Hot waterfor pools

Solar Water Heating (SWH orSolar Thermal)

Hot waterfor domestic use (DHW)All courtesy of DOE/NREL

Water Heating

Solar Electricity

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Solar Electricity

Photovoltaic Effect

photo = l ight; vol taic = produces vol tagePhotovoltaic (PV) systems convert l ight directly

into electricity (using semiconductors)

Electron Orbits

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Electron Orbits

Free electron

How a PV Cell Works

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How a PV Cell Works

Antireflective coating

N-Layer (Phosphorus)

P-N Junction

Metallic Contact Finger(electron pickup)

P-Layer (Boron)

Electron flow

-

+Metallic back contact

Sunlight

Solar Cells & the PV Effect

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Usually produced with semiconductor grade

silicon Dopants create positive and negative regions

P/N junction results in .5 volts per cell

Sunlight knocks available electrons loose forpotential electrical current

Wire grid provides path for current

Solar Cells & the PV Effect

PV Terminology

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ArrayModuleCell

PV Terminology


PV System Sizing

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200 HP engine: means that 200

horsepower is the MAXIMUM it willproduce.

4 kW PV system: means that 4,000watts (4 kW) is the MAXIMUM it will

produce in full sunlight.

y g

Crystalline Silicon (Mono)

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Source: DOE National Renew able Energy Laboratory

Crystalline Silicon (Poly)

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Source: Darren Bouton

y ( y)

Crystal l ine Si l icon PV Products

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64Source: DOE Nat ional Renewable Energy Laboratory

Firm, like crystals

Longest track record, over 50 years

Most common, over 85% of the market

Highest efficiencies: avg. 15%, up to 22%

Requires about 100 sf. per kilowatt

Thin-Fi lm PV Products

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66

Pacific Energy Center

San Francisco

Sour ce: DOE Natio nal Renewable Energy Laboratory

Can be applied on many different materials

Longevity still to be proven

Production growing at high rate

Lower efficiencies: avg. 7%, up to 15%

Has potential for big cost reduction

Requires about 200 sf. per kilowatt

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PV General Rules

Crystal l ine PV Products

Efficiencies (rated) range from 12-22%Space required: 90-150 s.f. per kW


Efficiencies (rated) range from 5-10%

Space requi red: 170-300 s.f. per kW

Crystalline vs. Thin-Film

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1.2 kWCrystallineSilicon


1.2 kWThin-Film

Thin -film needs about twice as much

space fo r the same-size system, bu tthe total cost is about the same.

Efficiency vs. Capacity

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1.2 kW (1,200w)75 square feet16w per sq.ft.


1.2 kW (1,200w)150 square feet8w per sq.ft.

Capacity = totalpower

Efficiency =power per sq.ft.

Heat effect

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Courtesy: Schott Solar

Air temperature70 F

Under modules120 F

Roof surface100 F

Crystal l ine vs. Thin-Fi lm: Heat response

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Heat increases electrical resistance, whichlowers power output.

Output begins dropping at 20C (68F).

Percentage of drop is called Temperature

Coeffic ient of Power. It is measured in % per degree Centigrade,

i.e. -0.35%/C

Thin film degrades less than crystall ine.


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Crystalline -0.478% Thin film -0.19%

Sample data from spec sheets


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60

65

70

75

80

8590

95

100

20 25 30 35 40 45 50 55 60 65 70

Degrees Centigrade

%o

fPower

Thin Film Crystalline

(68) (86) (113) (140)

(Fahrenheit)

PV Panel Technology SummaryModule Cell Sample Companies

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Technology Descr iptionEfficiency

CommercialEfficiency

LaboratorEmploying

Techno lo ies

Cryst alline Silicon

Single Crystal Grown in Cylinders and wire- orlaser-sliced into circular wafers as

thin as 200 microns. Cells are

circular and modules are inherently

flat black or charcoal.

14 - 15% 25% BP Solar

GE/AstroPower

Sanyo

Sharp

SunWorld

Multi-Crystalline Cast in blocks or drawn through adie to create a "ribbon" and wire-

sliced or cut into rectangular

wafers. Cells are typically vibrantblue.

12 - 14% 19% BP Solar

Evergreen Solar

Kyocera Solar

Schott SolarSharp

SunWorld

Thin-Film Materials

Amorphous Silicon(a-Si)

Cell and module production part of

same process. Widely used in

consumer products and on flexible

substrates.

5 - 7% 13% BP Solar

Kaneka Solar

TerraSolar

United Solar Ovonic

Copper Indium Diselenide

(CIS)

Alternative semiconducto r material

under commercia lization.

8 - 10% 19% Global Solar

Shell Solar

Cadmium Telluride(CdTe)

Alternative semiconducto r materialunder commercia lization.

7 - 9% 17% BP Solar First Solar

Near single-atom vapor or electro-deposition on low-cost materials (glass, stainless steel, or

plastic). Modules can be flexible. Appearance dark charcoal to near black; can also be semi-

transparent.

The orignal approach; grow silicon crystal structures in a variety of ways. Represents almost 90%

of total market. Appearance dark blue to black but other colors possible with changes to anti-

reflective coatings.

Growth Forecast?

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Source: Renewable Energy World.com

Inverters

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76Pacific Energy Center

San Francisco

Inverter

DC AC

Changes Direct Current (DC) to

Alternating Current (AC)

Inverters

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San Francisco

Range in size from 1 Kw to 500+ Kw

Can easily be connected together,even different models

Best to locate in cooler area


Inverters

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San Francisco

Strings must be of specific length and number,of equal size, and on the same plane.

Power production is very sensitive to shading.

Inverter

Strings of modules

Typical system layout

Panel &meter

System Inverters: Online string sizing tool

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San Francisco

Limited configurations, cannot deviate.

Inverters

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San Francisco

Micro-inverter

One per module

Inverts DC to AC right there

Combiner box &communicator

Panel &meter

System layout

Reliability

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San Francisco

Source: NASA

Reliability

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Mature technologyover 50 years old Essential to the space program

Millions in use Products tested and approved by CEC Long warranties backed by large,

stable companies

20 to 25 years on panels

10 to 25 years on inverters 10 year labor warranty

It works during the day, but what about at night?

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83


Previously, there was

only one solution:Store the excess inbatteries during the day,then draw off thebatteries at night, orwhen its cloudy.

But now?

Net Metering

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The uti li ty grid is a two-way street!

Electrici ty can be sentback to the grid by thecustomer.

Eliminates the need for batteries.

Reduces cost and maintenance.

Ensures a constant supply of electrici ty.

XSource: Andy Black

Source: DOE NREL

Source Andy Black 2006 All rights reserved.

Typical System Components

Array Inverter

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Meter

LoadsSource: Darren Bouton

Balance of System

(BOS)

Panel

Typical System Components

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86

1. Solar array

2. Inverter

3. House electrical

panel

Source: PG&E

Monitoring

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Extra hardware sends inverter data to internet

Inverter company or 3rd party hosts website

Customer can view system from home or remotely

Current and historical data can be displayed

Can cost extra but somecompanies are offering it asstandard package.

Cou rtesy SMA htt p:/ /www.sma.de/en/products/monitor ing-systems/sunny-beam-with-bluetooth r.html

Monitoring

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Total system history.

Real-time, per panel.

Cou rtesy Enphase ht tp: //enligh ten.enphaseenergy.com/public /systems/LWtm4844

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89

Feasibility

Solar Geometry

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90

Solar Geometry

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91

Plane of the Ecliptic

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92

Solar Geometry

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93

ACTUAL:The sun radiates in all

directions.

EXPERIENTIAL:On Earth all radiation from the

sun is parallel to one another.

Horizonin winter

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94

Source: Wikipedia

Horizon insummer

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95

This ray strikes parallel to the surface.

This ray strikes perpendicular to the surface.

This ray strikes +45 degree angle to the surface.

Latitude and Longitude

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96

Sun Path

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97

NS

E

W

Spring/Fall Noon:90o Latitude52.5o in SF

Winter Noon:90o Latitude 23.529o in SF

Summer Noon:90o Latitude +23.5

76o in SF

Winter: Rises 30o south ofE

Summer: Rises 30o north ofE

Source: PG&E

Sun Path Overhead Projection

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98

Sun Path Overhead Projection

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99

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100

Source: NASA

Summer sun

Winter sun

Sun Path Horizon Projection

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101Edward Mazria. Passive Solar Energy Book, Expanded

Professional Edition

Rodale Press, 1979, Pg. 311

Sun Chart: San Francisco

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Source: University of Oregon, Solar Radiation Monitoring Laboratory

http://solardat.uoregon.edu/SunChartProgram.html

Does the si te havean appropriate southern exposure?

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103

Use a compass to identi fy north (and thus south),a fi rst step in assessing solar access at a site.

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104

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105

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106

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107

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108

San Francisco: declination = 14

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109

In west:

True azimuth = Compass azimuth + Declination

True south reads as 166

true

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110

In east:

True azimuth = Compass azimuth - Declination

true

Magnetic South vs. True South

Magnetic South = Compass South

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111

A compass aligns with the earths magnetic field, which is not

exactly aligned with the earths rotational axis. Magnetic Declination = the number of degrees that true south is

east or west from magnetic south.

True south ~ 15 east of magnetic south

(SF, SJ, Stockton)

Magnetic South = Compass South

True South = Solar SouthNOTE: go to National Geophysical Data Center (NGDC) at

http://www.ngdc.noaa.gov/seg/geomag/jsp/Declination.jsp

to determine your sites magnetic declination

Describing Location of the Sun

First understand where it is!

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Azimuth - horizontalangle of sun east or westof due south

Altitude - angle of sunabove the horizon

Azimuth and altitudedescribe the location ofthe sun in the sky at agiven time.

Illustration from Environmental Control Systemsby

Fuller Moore, McGraw-Hill, Inc., 1993, p. 76.

270

180

90

0

45

1 S t ti l (i l ti )

PV Siting Issues to Consider

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113

1. Sun energy potential (insolation)

2. Space

3. Shading

4. Orientation (N S)

5. Tilt angle6. Aesthetics

Peak Sun Hours Equivalent

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114

Digital sunlight

1000

w/m


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115

0

500

1000

1500

2000

2500

3000

3500

1 3 5 7 9 11 13 15 17 19 21 23

Hours of t he Day

KwhProduced

Typical daily pattern

3 00


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116

0

500

1000

1500

2000

2500

3000

3500

1 3 5 7 9 11 13 15 17 19 21 23

Hours of t he Day

KwhProduced

Equal areas

What is the solar resource potential?

Peak Sun-hours Measured in kWh/m2/day

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117Source: DOE National Renewable Energy Laboratory (NREL) Resource Assessment Program

http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas/serve.cgi

What is the solar resource potential?

Peak Sun-hours Measured in kWh/m2/day

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118

Monthly Percentages

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Percentage of yearly insolation per month

Ratio of sunniest six months to least sunny (summer to winter)

Source: morehead.unc.edu

Cali fornia cl imate ideal for solar

Weather/Sun Potential Summary

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120

Panels produce in al l l ight

Fog has cooling effect, which raises

efficiency

Microcl imates l ikely less than 15%

loss from normal

Roof / Ground Area:

Space Requirements

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121

Crystal l ine Si l icon

90-150 square feet per kW

Thin-Film

170-250 square feet per kW

Note: Consideration should also be given for access

to the system (can add up to 20% of needed area)

For a 4 kW residential system:

Crystalline: 360 to 600 sf.

Thin fi lm: 650 to 1000 sf.

Space Requirements: Overhead Photos

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122

47 x 13 = 611 sf.

PV Orientation

NorthFor til ted roof:

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123

West East

South

OKVerygood

Good

Not

good

N

PV Orientation

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124

W E

S

Overheadmaps: true N-S

Tilt

Tilt = Angle at which the collectors aremounted relative to 0 (flat horizontal surface)

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125

mounted relative to 0 (flat horizontal surface)

tilt angleEx. 30

Tilt

12 ft.

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126

4 ft.

18 deg.

Typical roof in this area is 4:12.

For every 12 feet horizontal, it drops 4 feet.

This equals 18 degrees up from horizontal.

Normal roof pitch is a very good mounting angle.

South

Tilt Angle vs. Building Orientation

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127

0

Flat

18

4:12

30

7:12

45

12:12

60

21:12

90

Vertical0 (South) 0.89 0.97 1.00 0.97 0.89 0.5823 (SSE, SSW) 0.89 0.97 0.99 0.96 0.88 0.59

45 (SE, SW) 0.89 0.95 0.96 0.93 0.85 0.60

68 (ESE, WSW) 0.89 0.92 0.91 0.87 0.79 0.57

90 (E, W) 0.89 0.88 0.84 0.78 0.70 0.52

Source: A Guide to Photov oltaic (PV) System Design and Installation -- CEC, June 2001

Orientati

on/Degrees

fromS

Bottom line: Tilt is a factor, but not a major one.

Tracking

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128

Cou rtesy of DOE/NREL

For most home systems, the extra expense and maintenance oftracking motors is not worth the eff iciency gain. Better to buy a fewextra panels.

For large commercial systems it may be worth it.

Will the PV system be free from shade?

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129Source: DOE National Renew able Energy Laboratory

72-cell PV module

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Copyright Solmetric 2010

+

72-cell PV module with bypass diodes

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+

Module I-V curve with shaded cell strings

Cell

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I

VCell string

Shade one cell of one cell stringOne bypass diode turns on

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I

V

Shade one cell in each of two cell stringsTwo bypass diodes turn on

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I

V

Monocrystalline Shading Effect

Partial Module Shading Effect3

UnshadedModule

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135

0

0.5

1

1.5

2

2.5

0 5 10 15 20 25

Volts

Amps

Unshaded Module

1 cell 25%

shaded

1 cell 50%

shaded

1 cell 75%

shaded

1 cell 100%

shaded

The Extreme Effects of Shading

% of One Cell Shaded % Loss of Module Power

0 % 0%

25 % 25 %

50 % 50 %

75 % 66 %

l00 % 75 %

with 3 cells shaded 93 %

Courtesy: Solar Energy International

Per-Module Devices

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Solar MagicNational Semiconductor

Module MaximizerTigo Energy

PowerBoxSolar Edge

Enphase Microinverter

Enphase Energy

Direct Grid Microinverter

Direct Grid Technologies

SunMizer

Xandex

Parallux vBoost

eIQ Energy

PV AC ModuleEXELTECH

Microinverter

Per-Module Devices: Two Basic Types

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Changes DC to ACNeeds no other inverter

Module MaximizerTigo Energy

Enphase MicroinverterEnphase Energy

MaximizerAdjusts DC voltage: DC to DC

Needs system inverter

PV Requirements

Solar Access

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138

Solar Window = 9 am - 3 pm (ideal)8 am - 4 pm (possible)

Need minimum of 4 hours during solar

window with no shade (prefer 5 hours)

Summer more important than winter

Shading

Solar WindowSunriseSunset

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139

Shade-free from 9 to 3

Good chance for PV

Shading

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140

Bad chance for PV

Planning for Shade

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141Sourc e: PEC Staff

S 2 to 1 ratiorecommended

Planning for Shade

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142Sourc e: PEC Staff

2 ft .

1 ft .

No good

Solar Pathfinder

Used to gain a quick and approximate understandingofsolar access and objects on the horizon that shade a

given location.

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143

Latitude specific sun path diagram isplaced in the pathfinder.

The transparent, convex plastic domereflects objects on the horizon, enablingthe user to see the relationship betweenthese objects and the path of the sun.

Obstructions can be traced onto sunpathdiagram.

g

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144Courtesy of Andy Black

Solmetric SunEyeTM

110210

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145

Courtesy: Solmetric, Corp.

Sunpath View

Visuallydemonstrates

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146

seasonal sunpath andshading effectsof obstructions

Summarytabular data


Detailed View

Chart shows

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147

proportion of totalsolar energyavailable at thissite each month


Where to Go for Tools

Pacific Energy Center: Tool Lending Library

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148

gy g y

Phone: 415-973-9945Email: [email protected]

Pacific Energy Center Web Site:www.pge.com/pec/tll

How will PV affect site aesthetics?

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149Source: Darren Bouton

How will PV affect site aesthetics?

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150Source: Darren Bouton

Don t put a new PV system on an old roof!

Minimum roof l ife should be 5 7 years.

G d id t d PV d f t ti

Roof Issues

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Good idea to do PV and roof at same time

Estimate for panel removal/replacement is $1,000 perKw of system size.

Cou rtesy Lon don Flat Roofing, Ltd http://www.londonflatroofing.co.uk/flat-roof-repairs/asphalt-flat-roofs/

www.csi-epbb.com

Official program for CSI rebate, everyone must

Online Production Calculator

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p g y

use. Buyers dont have to trust the salesperson .

Takes all relevant factors as input and gives

estimated annual production and rebateamount.


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Online Production Calculator: Shading

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Online Production Calculator: Shading

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No shade With shade

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158

Finances

Sell Power to theUtil ity by Day

Net Metering

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159


y y y

Buy Power at Nightand Winter

Exchange at Retail Annual Cycle

.


Net Metering No Blackout Protection

Unsafe to send livepower into grid while

workers repairingX

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160



p g

downed lines

XNo voltage reservoirmeans house currentcould fluctuate anddamage appliances

Reduce Your Energy Bills!

Spin Your Meter Slower Use the electricity you generate

first to reduce electricity youwould normally buy from the

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would normally buy from the

utility or electric service provider

Spin Your Meter Backwards

Excess electricity generatedgoes through your meter andinto the grid

Spins your meter backwards!

Get credit for stored electricityon the grid

Net Metering

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Customer side Utility side

Meter

Generation: 3 kWh Surplus: 2 kWh

Net Metering

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Meter

Load: 1 kWh

p

Cash credit: $ .60

2 kWh @ $(going rate)

Generation: 1 kWh Surplus: 0 kWh

Net Metering

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Meter

Load: 1 kWh

p

Cash credit: $ .00

Need: 1 kWhGeneration: 0 kWh

Net Metering

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Meter

Load: 1 kWhCash debit: $ .09

1 kWh @ $(going rate)

What do you get paid if your system over-produces?

Wholesale cost: $.10/kwhMarkup to cover grid

maintenance: $.06/kwh

Cost of power at $.16/Kwh

Net Metering

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166

CPUC rulePG&E must comply

The full retail rate that PV owners get paid for their

power includes a subsidy (markup) that comes fromall rate payers.

The CPUC determined that this full subsidy wouldonly be allowed to cover your usage, not for you to go

into the power-generation business. For over-product ion, compensation will be at a lower

rate, to be determined.

Net Metering

750

kWh/mo

Roll over

Av erage monthly usage

PV system product ion

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167

OctoberMay April SUMMER WINTER

250

500

750

kWh/mo



The surplus covers the shortfall,and your yearly bill is minimal.

Net Metering

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250

500

750

kWh/mo



PV system produces less thanyour yearly usage.

Net Metering

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169


250

500

You pay th is amount

750

kWh/mo



PV system produces morethan your yearly usage.

Net Metering

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170


250

500

You are paid a different rate for th is amount around 4 per kWh.

Two fundamentally different concepts:

Net Metering

Methods of Payment

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171

Serves the onsite load FIRST, theninteracts with the utility grid.

Feed-in TariffDoes not serve the onsite load andONLY interacts with the utili ty grid.

One meter

Two meters

Generation track

Feed-in Tariff

Feed-in (credit)Meter

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172

Usage track

Usage (debit)

Meter

Net Metering vs. Feed-in Tariff

Net Metering:

For PV systems from 1 kW to 1 mW

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173

Feed-in Tariff:

For PV systems from 1 mW to 20 mW.See www.pge.com/feedintariffs

Net EnergyMetering

CaliforniaSolar

Initiative

Available

PG&E

Programs

SelfGenerationIncentiveProgram

PG&E Renewable Energy Programs

SolarWaterHeating(CSIThermal)

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174

Customerscale Utilityscale

NetEnergy

Metering

UtilityOwnedRenewables*

Programs

FeedinTariffPrograms*

RenewablesRFO

RenewableAuctionMechanism*

PVRFO*

SystemSize 1

kW 1

MW 100

MW

++20

MW100

kW 3

MW

*Neworrevisedprogram

RenewableAuctionMechanism*

Rate Schedules (Tariffs)

Two main types of residential rates:

TIERED (E-1)

Th th

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175

The more you use, the more you pay.Baseline amounts plus tier charges based onpercentage of baseline.

Time-of-Use (TOU)

Additional factor depending on when youuse the power.

PG&E BaselineTerri tory Map

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176

Baseline=guaranteed minimumamount of low cost electricity

for everyone--all income levels.

Baseline allocation determined bygeographic territory averages.

PG&E Baseline Territory Allocations

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177

PG&E monthly electric bill for a large home user:

Tiered Rate (E-1)

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178

PG&E monthly electric bill for a large home user:

Tiered Rate (E-1)

Baseline = 9.8 x 33 = 323.4 kWh

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179

978.00

= $ 38.41= $ 13.10

= $ 65.79= $ 129.46= $ 3.12

$ 249.88

Used 978 Kwh costing $ 249.88

5 rate tiers1

2

34

5

Baseline 9.8 x 33 323.4 kWh

Breakdown of charges:

Tiered Rate (E-1)

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E-1 / PG&E Standard Rate Schedule (Residential)

PG&E E-1 Residential Rate 6/1/10

29.1

40.0 40.0

30.0

35.0

40.0

45.0

Wh

29.5

33.5 33.5

As of 1/1/12

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11.913.5

0.0

5.0

10.0

15.0

20.0

25.0

Less than

100%

101% -

130%

131% -

200%

201% -

300%

Over 300%

Percentage of baseline allocation

CentsperkW

12.8 14.6

29.5

The less you use, the more you eliminate theexpensive upper tiers:

Rate Tiers

5 rate tiers1

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182

978.00

= $ 38.41= $ 13.10= $ 65.79= $ 129.46= $ 3.12

$ 249.88

1

2

3

4

5

The less you use, the more you eliminate theexpensive upper tiers:

Rate Tiers

$5 rate tiers

1

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183

Used 421 kWh cost ing $ 51.52

Lowering the usage 57% lowers the bill 80%.

From 978 Kwh to 421 Kwh -- from $250 to $50.

421.42

= $ 38.41= $ 13.10= $ 65.79= $ 129.46= $ 3.12

$ 51.52

1

2

3

4

5

PG& E E-1 Residential Rate 6/1/10

29.1

40.0 40.0

25 030.0

35.0

40.0

45.0

kW

h

29.5

33.5 33.5

As of 1/1/12


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11.913.5

0.0

5.0

10.0

15.0

20.0

25.0

Less than

100%

101% -

130%

131% -

200%

201% -

300%

Over 300%

Perce ntage of baseline allo cation

Centsper

12.8 14.6

PG& E E-1 Residential Rate 6/1/10

29.1

40.0 40.0

30.0

35.0

40.0

45.0

Wh

29.5

33.5 33.5

As of 1/1/12


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185

11.913.5

0.0

5.0

10.0

15.0

20.0

25.0

Less than

100%

101% -

130%

131% -

200%

201% -

300%

Over 300%

Perce ntage of baseline allo cation

C

entsperk

12.8 14.6

Solar reverses therate tier effect

Lower ROI Higher ROI


1. Reduce overall load. Energy efficiency, conservation

2. Inform people so they can cooperatevoluntarily. Publicity, Flex Your Power alerts

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186

Publicity, Flex Your Power alerts

3. Create the ability to remotely turn offcertain appliances. Smart AC, smart meters, etc.

4. Charge more for peak usage. Time-of-Use rates, Peak-Time pric ing

and others.

Time of Use Rates

17,000

19,000

21,000

PG&E Peak LoadJuly 25 @ 1700 hours

20,883 MWs


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187

5,000

7,000

9,000

11,000

13,000

15,000

Jan Fe b Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Time of Use Rates

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188

Time of Use Rates

Sunday Monday Tuesday ednesda Thursday Friday Saturday

Midnight - 6am Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak

6am - 10am Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak

10am - 1pm Off-Peak Part-Peak Part-Peak Part-Peak Part-Peak Part-Peak Off-Peak

Residential "E6" Time-of-Use Pricing Periods

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1pm - 7pm Off-Peak Peak Peak Peak Peak Peak Off-Peak

7pm - 9pm Part-Peak Part-Peak Part-Peak Part-Peak Part-Peak Part-Peak Part-Peak

9pm - Midnight Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak Off-Peak

Peak rates in Summer Afternoons 29/kWh + tier surcharges

Part-Peak rates: 14/kWh + tiers

Off-Peak rates (Nights & Weekends) 8.5-10/kWh + tiers

20

25

30

35

perK

wh

Time of Use Rates

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190

0

5

10

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours of the Day

Cents

E-6 summer rates (May October)

2000

2500

3000

3500

oduc

ed

Time of Use Rates

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191

0

500

1000

1500

1 3 5 7 9 11 13 15 17 19 21 23

Hours of t he Day

KwhPro

Typical summer production

20

25

30

35

sperK

wh

Time of Use Rates

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192

0

5

10

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours of the Day

Cents

Summer pattern (May October)

1

20

25

30

35

sperK

wh

Time of Use Rates

Buy Buy

Sell

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193

0

5

10

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Hours of the Day

Cents

Buying low and sell ing high adds value.

Med

High

On-peakusage

Should I go on a TOU rate with my PV system?

No

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25% 75%50% 100%0

Low

Percentage of yearly usage covered by solar

Yes

With PV: Change in Utility Billing

Two bil ls, gas & electric

Yearly bi ll ing cycle for electricity

Fixed minimum electric charge reflected on

gas (blue) bill

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195

Change in Utility Billing

Minimum

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196

electrichookupcharge


Minimumelectriccharge

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197

Current monthlycharge

Cumulativecharge


PV electric bill : meter readings

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198


PV electric bill : usage history

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Yearly trueup example

Yearly usage total $170.20

Already paid the fixed amount of $6.71 perth f 12 th t t l f $80 52

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200

month for 12 months, total of $80.52

Amount owed is 170.20 80.52 = $89.68

Relatively Low Maintenance

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Soiling Factors

Three basic categories for rainy / dry season areas

Washed as often as necessary ~ 1.0

Washed once in July ~ 0.96

Never washed ~ 0.93

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Factors affecting number

Rainy / dry seasons Dirt roads

Near agricultural activity

Close to road surface of busy street

In airport flight path

Cleaning Costs

Residential systems

Around $5 per panel

High because of fixed costs (travel, insurance, etc.)

Commercial systems

In PPA, contracted out to separate company

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Cleaning and inspections typically done together

Frequency usually twice per year

Full service cost about 2/watt per year

One time cleaning-only cost around 1/2/watt or $1/panel

Must be careful with power washers, psi not too high

500 kW system = 2,500 panels:Yearly cleaning & maintenance = $10,000.

Environmental Footprint Best overall estimates from 1 to 2.5 years

Depends on si te and power production--inCalifornia is about 1.1 years.

Shrinking as costs drop and production gets

greener

Pays back 10 to 30 times or more its

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environmental cost

Most PV manufacturingplants will have their ownPV system on the roof.

Cou rtesy of DOE/NREL

Source: January 2008 Environmental Science & Technology

http://sustenergy.blogactiv.eu/2008/05/29/emissions-from-photovoltaic-manufacturing/

CPUC (California Public UtilitiesCommission)

Existing ResidentialExisting Commercial

Commercial New Construction

Residential New Construction

CSI

(C lif i S l I i i i )

NSHP

(N S l H P t hi )

California Solar Initiative (CSI)

CEC(California Energy Commission)

SB 1

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(California Solar Init iative) (New Solar Homes Partnership)

PG&E SCE CCSE(SDREO)

Program Administrators

SDG&EPG&E SCE

Program Administrators

The CSI makes PV

Economical:Gives financial incentives to lower the cost

SecureScreens and tests equipment

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Requires long warranties

Helps screen and check installersStandardizes production estimates

EasyHelps installers handle everything

CSI Financial Incentivestwo types

EPBB (Expected Performance-Based Buydown) One-time, up-front payment (rebate) Based on expected production

Only for smaller systems (< 50 kW)

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PBI (Performance-based Incentive) Ongoing monthly payment for 5 years Based on actual production

Possible for all systems, but required forlarge ones (> 50 kW)

CSI Financial Incentivesnumbers

EPBB PBI

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Overall outline:

Incentives step down according to amount of PVinstalled (MW)

Data as of 2/7/12

CSI Financial Incentivesnumbers

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MW remaining MW under rev iew = best estimate of how much left.For PG&E residential: 26.48 1.08 = 25.4 MW.

Trigger Tracker. Helps determine when incentives drop.

http://www.csi-trigger.com/

Base system size in AC kilowatts (CEC) may be

adjusted downwards depending on designand geography.

Determined by EPBB calculator: www.csi-epbb.com

according to the following inputs:1. Zip code

CSI Rebate Adjustments

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2. Orientation (azimuth)

3. Tilt (from horizontal)4. Shading (detailed shading table)

Design rewards summer energy, not annual

No design penalty for any orientation from South to West

Geography factor capped at 1.0 relative to Orange, CA

Case study

Electric bil l: $100/month = $1200/year

After 10 years you will have paid $12,000

if rates do not rise

Sample Current Situation

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if rates do not rise.

Is this a reasonable assumption?

Case study

Electric bill: $100/month = $1200/year

With inflation, after 10 years you l ikely will have paid$14,000 to $17,000

With nothing to show for it except higher electric bi lls($150+/mo)

Sample Current Situation

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($150+/mo).

No equity

Nothing paid off

So the real question is

Can solar be less expensive than this?

PV Statistics & Performance forthe Average Family of Four

(monthly electrical bill $100-$200)

4.0 KwAC System

COST (before rebate = $6,500 / kW) $26,000REBATE (est. $230 / kW) $920

TAX CREDIT $7524NET COST $17,556Maintenance (25 40 yrs.) $5,000

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( y ) ,Total lifecy cle cost $22,556

kWh Production ~ 6,500 kWh / year

Space requirements ~ 350 - 500 s.f.

Avg. cost of power now ($150/mo) $.18/Kwh

25-yr. cost of power (est.) $.14/Kwh40-yr. cost of power (est.) $.09/Kwh

Three Ways to Buy

1. Full purchase (cash or borrowing)

Owner of system

Borrow money or pay cash

Full payment up front

Design and install

Sell

You PV Vendor

$$$

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Maintain and monitorsystem

Economics:

Cash / total savings

Loan pmt. / monthly savings

Honor warranties

(equipment & labor)

Three Ways to Buy

2. Solar Lease

Low or no money down

Fixed lease payment

Owner of systemDesign and install

Lease

You PV Vendor

$

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Fixed lease payment

Possible buyout in thefuture

Economics:

Lease pmt. / monthly

savings

Maintain and monitor

systemHonor warranties(equipment & labor)

Remove system at end if

needed

$

Three Ways to Buy

3. Power Purchase Agreement (PPA)

Low or no money down

Monthly power payment

Owner of system

Design and install

Sell power

You PV Vendor

$

$

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Monthly power payment

Possible buyout in thefuture

Economics:

Monthly pmt. / monthly

savings

p

Maintain and monitor

systemHonor warranties(equipment & labor)

Remove system at end if

needed

$

Solar lease

Lease

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Solar lease

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PV System Costs by Component

Retai l costs of system under 30 kW

PV Panels ~ $2 per Watt

Inverter ~ $.50 per WattBalance of System ~ $1 per Watt

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Installation / Labor ~ $3 per Watt

Total cost ~ $6.50 per watt instal led

Whats the

THE BIG QUESTION:

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What s thepayback?

Return on Investment

Payback: Time period when savings = investment cost

IRR (internal rate of return): Percentage of annual returnwhich looks at full li fe cycle

Different ways to measure

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221

NPV (net present value): Cash flow projection which takes

in financing costs

Monthly Cash Flow: Change in your monthly payment

Monthly Cash Flow:

Financed by a home-secured loan

Loan interest is tax-deductible

Assuming historical rate escalation continues

Monthly cash flow can be immediately positive formany people with higher electric bi lls.

Return on Investment

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222

They can start making money from day one and

continue for over 30 years!

Lower bil l amounts wil l typically start out slightlynegative and improve over time.

When the price per kWh of electric ity from a

renewable source is equal to the current averagegrid price.

PV example:

System net cost: $20,000, lifetime maintenance $4,000.

Grid Parity

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223

Expected to generate average of 5,000 kWh per year for 30years, total of 150,000 kWh.

$24,000 / 150,000 = $ .16 per kWh

Current utility average price = $ .16 per kWh

= Grid Parity

Appraisal Value Will likely go up Less utility cost means more money available for mortgage

payment

Data so far is supportive, new report just released

Much more to come as solar houses turn over

S l Ri ht A t

Increase in Home Value

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Solar Rights Act

California law that supports solar Keeps HOAs and other CC&Rs from prohibit ing solar systems

Forbids increased property taxes on owners system

Restriction ends when home is sold, and assessment can go up

to reflect system

WefindcompellingevidencethatsolarPVsystemsin

Californiahaveboostedhomesalesprices.

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http://eetd.lbl.gov/ea/emp/reports/lbnl4476e.pdf

Called RECs or green tags

The green attribute of the power

Connected to carbon offset accounting

Central feature of a system to move moneyfrom polluters to non-polluters.

Renewable Energy Credits

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226

from polluters to non polluters.

Polluters must buy RECsaccording to penalty.

Cap and Trade

Penalt

Renewable Energy Certi ficates Good guysBad guys

Trade

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227

Polluters

Pollution preventers

Pollution removers

Cap

Permitted

Penalty

Source: W ikipedia free license

Making activity carbon neutral

Funding projects that remove as muchcarbon as you generate

Additional social & business image value

Carbon Offsets

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228

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Strategies for Cost Reduction

Strategies for Cost Reduction

Instal lation efficiencies/roofing

Multiple benefi ts from one strategy Design integration

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Package with energy efficiency The PV Bulk-Buy?

Installation Efficiencies

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PV Roof Tiles BIPV Building Integrated Photovoltaics


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Tiles interlock quicklywith NO roof penetrations



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PV Integrated Roofing Membrane

Courtesy: Solar Integrated


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PV Skyl ights


Multiple Benefits

Mitigate unwantedsolar heat gain

Control glare

Displace existingmaterials cost

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materials cost

Produce electricity

Package with Energy Efficiency

Conservation gives best payback

Many EE rebates avai lable

Wil l be required for rebate

Can handle enti re package for cl ient

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p g


PV Bulk Buy

Community targets for total Kw

Can lead to 10% or more discounts

Many companies offering i t

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Source: Pete Shoemaker

Sales and InstallationProcess

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Case Studies

Residential Case Study

John Doe in Gilroy, CA $200/month PG&E electric bill

Usage projected to stay the same

Phone screening information:

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Usage projected to stay the same

Composition shingle roof

Thinks there are no shade issues

Overhead photos not clear

Roof Layout

NW E

S

Front ofhouse

Back ofhouse

Site Visit Data:

4:12 pitch

25

65

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NW E

S

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Source: Pete Shoemaker

Site Visit First Pass

No shading issues

Roof in good shape

About 200 sf. south-facing

Lots of room west-facing

Good site for inverter(s)

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Good site for inverter(s)

Electrical service and panel OK

Substantial electric bill

What Size System?

Usage pattern normal

Monthly average is good

starting point

Propose maximum sizesystem and then work to

Usage History

Jul-06 946

Aug-06 1127

Sep-06 1349

Oct-06 970

Nov-06 1093

Dec-06 1077

Jan-07 1349

Feb-07 867

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customers budget

Check for competitivebids, ask to see them

Mar-07 886

Apr-07 768

May-07 815

Jun-07 836

Total 12083

Avg. 1007

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Acme Solar final bid

24 190-w att modules

Tw o 2000-w att inv erters

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Commercial Case Study

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Car dealership in Gilroy

Check usable space

Estimate maximum size of system

Determine average usage from bill

Give ballpark financial numbers

Commercial Case Study

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140

80

90

90

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30 x 40

Total space is about 16,000 square feet, but how muchis usable? Need site visi t to determine.

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Visual estimate about60+% usable space.

about 10,000 sf. total =

100 KW systemmaximum.

Electric bill yearly average: 31,000 Kwh/month

Average blended rate per Kwh = $ .16594

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Average monthly bill = 31,000 x $ .16594 = $5,144

or about $5,000 per month.

From websi te: www.csi-epbb.com

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Page 1

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Page 2

This image cannot currently be displayed.

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STEP 1: Complete an Energy Survey STEP 2: Contact and Choose an Installer

INSTALLER HANDLES THE REST

STEP 3: Complete and Submit Applications for CSI

STEP 4: Obtain Building Permits

PV Sales-Installation Process

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STEP 5: Install System STEP 6: Schedule Final Build ing Inspection

STEP 7: Schedule Final Uti lity Inspection

STEP 8: Claim Incentives

Find Installers

Personal references

CSI website

http://gosolarcalifornia.org

CalSEIA Membershttp://calseia.org/, Find an Expert link

Internet

Ad i i

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Advertising Better Business Bureau

Diamond Certi fied

Comparing Bids: DC vs. AC watts

DC watts are name only DC rating is determined under

Standard Test Conditions (STC), not

real-world DC must be changed to AC beforeuse

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DC system size: 20 Sharp 200-wattmodules

= 20 x 200 = 4000 watts = 4.0 kW DC


Lookup CEC ratings for panels.

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http://www.gosolarcalifornia.org/equipment/


Lookup CEC ratings for inverters.

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http://www.gosolarcalifornia.org/equipment/

AC watts are real power AC rating is determined under Practical

Test Conditions (PTC), real-world

AC takes efficiency losses into account

AC system size: 20 Sharp 200-watt modules

PTC rating 176 atts in erter efficienc 96%


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PTC rating 176 watts, inverter efficiency 96%= 20 x 176 = 3520 watts x .96 = 3379 watts

= 3.38 kW AC

System size: 20 Sharp 200-watt modules1 SMA SB 4000US inverter

4.0 kW DC 3.38 kW AC (CEC rating)

DC is about 18% more, but misleading.

AC is the important number and if installer


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AC is the important number, and if installeronly gives DC numbers ask for CEC AC size.

1. Full price, before incentives. This includes all adders (such as extra roof charges), and extras(such as monitoring), an estimate for permit fees(around $300), and taxes.

2. The system size in similar units: CEC AC watts is thepreferred measurement.

3 The per watt price This is determined by dividing thef ll i b th t i Thi i th it i

Comparing Bids: Per-watt price

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262

3. The per-watt price. This is determined by dividing thefull price by the system size. This is the unit pricethat allows you to compare apples to apples . It wi lltypically be around $6.50/watt.

Base price: $20,000Roof adder: $2,000Permit fee: $500Total: $22,500

System Size:4.0 Kw DC3.38 Kw AC (CEC)(3,380 watts)

Per-watt price:

$22 500 / 3 380 = $6 65/watt

Comparing Bids: Per-watt price

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263

$22,500 / 3,380 = $6.65/watt

Three options:

1. 20 Sharp 185 panels, 3.19 Kw AC,

$6.05/watt2. 20 Evergreen 180 panels, 3.12 Kw AC,$6.45/watt

3 20 Kyocera 190 panels 3 28 Kw AC$6 90/ tt

Comparing Bids: Group discount

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264

3. 20 Kyocera 190 panels, 3.28 Kw AC,$6.90/wattIf group target of 100 kW is met, price

will drop to $6.00/watt

Class Quiz

Review of Learning Objectives

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Jobs Overview

andFuture Trends

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Solar Incentive Data: National and State

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Cour tesy DOEhttp://www.dsireusa.org/

Solar Installation Data: National and State

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http://openpv.nrel.gov/visualization/index.php Cour tesy NREL

Solar Installation Data: State

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http://www.gosolarcalifornia.org/ Cour tesy CSI

Detailed statistics

Solar Installation Data: State

Complete data file

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http://www.gosolarcalifornia.org/

Cour tesy CSI

# Installers by # of Systems 1/07 to 4/10 CSI Data

480502

191200

300

400

500

600

Information Available from Analysis of Full Data File

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39 32 26

0

100

1 system 2-10 systems 11-50 systems 51-99 systems 100-200 systems 200+ systems

Compiled by Verve Solar Consulting from data CaliforniaSolarStatistics.ca.gov

Courtesy Verve Solar Consult ing

Top 30 Residential Installers by total # installs

Acro Energy Technologies, Inc.Solar Technologies

SolarCraft Services, Inc.Premier Power Renewable Energy, Inc.

Independent Energy Systems, Inc. dba Real Goods SolarSun Light and Power

Advanced Solar Electric, Inc

HelioPower, Inc.Marin Solar Inc. DBA Real Goods Solar

NextEnergy Corp.Mohr Power Solar, Inc.

Stout & Burg Electric, Inc.SPG Solar, Inc.

Self-Install (Same as Host Customer)

Sungate Energy Solutions, Inc.REgrid Power, Inc. DBA Real Goods Solar

Borrego Solar Systems, Inc.Akeena Solar, Inc.

REC Solar, Inc.SolarCity

CSI Residential Projects # installed systems 1/07 to 4/10

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0 500 1000 1500 2000 2500 3000

Occidental PowerPotero Corp.

SunWize Technologies

The Solar CompanySungevity, Inc.

Luminalt Energy CorporationHorizon Energy Systems

Sierra Pacific Home & Comfort Inc.Sullivan Solar Power

Cobalt Power Systems, Inc.



1 539

1,6491,667

1,761

1,797

1,920

1,963

2,089

2,1052,181

2,852

2,862

2,889

4,191

4,419

4,913

5,265

6,347

8,199

10,110

11,413

17,211

34,013

Borrego Solar Systems Inc

SunPower CorporationAkeena Solar, Inc.

Permacity Construction

Premier Power Renewable Energy, Inc.

EI Solutions

SPG Solar, Inc. - Novato

Unlimited Energy, Inc.

Solar Integrated Technologies, Inc.Chico Electric

Bleyco Inc

Stellar Energy GP, Inc.

Erickson Construction Co.

Permacity Construction Corp.

Pacific Power Management, LLC

SolarCity

Conergy Projects, Inc.

BP Solar International, Inc.

SPG Solar, Inc.

REC Solar, Inc.

Team-Solar, Inc.

Sun Edison LLC

SunPower Corporation, Systems

Top 30 Lg Commercial CSI Installers

kWp installedthrough CSI

1/07 to4/7/2010

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1,0301,109

1,120

1,176

1,197

1,364

1,459

1,539

0 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000

Sunview Vineyards of California, Inc.INTERIOR ELECTRIC INCORPORATED

BAP Power Corporation

Solar Power, Inc.

Granite Bay Energy (Formerly GBEG dba Granite Bay Solar)

EI Solutions, Inc.

Sunlight Electric LLC

Borrego Solar Systems, Inc.



Solar job trends

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http://library.constantcontact.com/download/get/file/1105585926298-73/SWIC_EmployerSurvey_SummaryReport_1.23.2011.pdf

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http://library.constantcontact.com/download/get/file/1105585926298-74/2011Q4_SWIC_JobsReport_Summary_1+23+2012.pdf

Lead Generator (canvasser, outside sales) Sales 1 (inside sales, lead qualifier) Sales 2 (field rep, closer) Project Developer (creating and selling large, longer-term projects) Designer 1 (pre-sale, estimation) Designer 2 (typical designer category, creates plans and drawings) Designer 3 (large-scale, commercial) Project Manager (post-sale, operations) Application Processor (paperwork, rebates, etc.) Permit Processor (w/ building officials, inspections) PV Installer 1 (laborer, apprentice, entry level) PV Installer 2 (typical crew member) Installer Crew Lead Monitor ing / Maintenance

PV Job Categories

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Monitor ing / Maintenance Technician / Troubleshooter Safety Manager Financial Operations (work w ith banks, etc.) HR / Hiring Marketing

Smart Grid

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Adding information technology to the electric grid infrast ructure

http://www.smartgridnews.com/artman/publish/Technologies_Communications_Resources/CSR-2009-Env ironment-The-Smart -Grid-Vis ion-1563.html

Smart Grid

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Adding information technology to theelectric grid infrastructure

Source: NIST

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Cou rtesy PG&E

Smart Meter

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Gas Meter with SmartMeter Module

Gas Meter Module

Attaches to existing gas meters

Measures 5.5 x 6.5 inches

Transmits wireless signals to theData Collector Unit

20 year life span

A.k.a. Meter Transmission Unit(MTU)

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9/7/2012 2822010 Paci fic Gas and Electric Company. All righ ts reserved

Electric Network Components

Utility IQ

Relays Access

Points

Meters Head

End

3G Cellular

Network

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9/7/2012 2832009 Paci fic Gas and Electric Company. All righ ts reserved

From meter to the home

Near-time electric usageinformation

Timely price signals

Appliance / energymanagement control signals

From meter to utility

Customer electric use

Customer energy generation

(e.g. solar) Appliance response to energy

t t l i l

Internet

A Platform for InnovationCustomer Energy Management

PG&E Premi se

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management control signals

CEM network communication

SmartMeter communication

Paper

Wealth

Dont forget the bottom line

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Pete ShoemakerPacif ic Energy Center

851 Howard St.


(415) 973-8850

Contact Information

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(415) 973 8850

[email protected]

pv_basics

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