Introduction to Grid-Connected Photovoltaic

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• Introduction to Grid-Connected Photovoltaic
• Core Principles Before You Begin

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The Basics Before Equipment

• Why Photovoltaic (PV)?
• Grid Connected PV Systems What they look like
• Separating Hype from Reality Understand the
  difference!
• Whos Involved There are more people involved
  in all this than you think!
• Terminology Process vs. Equipment

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Why PV?

• Renewable Energy in Support of Traditional
  Utility Infrastructure
• Reduces Load on Grid
• Generation at Point of Consumption
• Reduces Traditional Energy Dependencies
• Environmentally Sound Energy Source
• Locks In Electricity Cost Up Front
• Initial Investment Pre-Paid Electricity
• Hedge against Future Electric Rate Increases

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The Basic System
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GC PV The Real World Separating Reality from
Hype

• Solar is THE answer Hype. It is definitely
  Part of THE energy answer, but it may not work
  appropriately for all situations.
• Every kW PV installed produces the same energy
  as one average Home Hype. Just as each person
  is different, so are our energy needs. Oh, and
  the Weather!
• Its Free Energy Hype. The Suns energy may
  be free, but the only free way to convert it to
  something useful is getting a SUNTAN!

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GC PV The Real World Separating Reality from
Hype

• It doesnt matter where you put it because its
  the right thing to do Hype. It isnt right
  if it doesnt work!
• If the Government just put more money into it it
  would be fixed in X years Double-edged hype.
  They need Justification to continue. Responsible
  Siting, System Design, Installations can remove
  a big part of the Double Edge by providing that
  justification.

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Sorting It All Out

• THERE ARE RULES TO FOLLOW!
• One Size Does NOT Fit All!
• Suitable Site Critical
• Electrical Usage
• Technology Equipment
• Utility Company
• Building Department
• Cost
• Incentives Tax Credits
• Other?

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Who is ALL?
The Bank
Environment
Neighbors
Utility Company
Building Department
Customer
Equipment Manufacturers
Contractor
Site Sunshine
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The Language of PV
Pay Attention! Things may not be what they
seem and not everybody speaks the same
language!!!!

• Equipment vs. Process Terminology
• Multiple Technologies Applications
• Laboratory vs. Real-World
• Understand What youre buying
• CEC Equipment Lists
• http//www.consumerenergycenter.org/cgi-bin/eligib
  le_pvmodules.cgi
• http//www.consumerenergycenter.org/cgi-bin/eligib
  le_inverters.cgi

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Key Process Related Definitions

• DG Distributed Generation. Electrical
  generation located at the site of consumption.
• Generator As related to process Entity owning
  and operating on-site generation facility.
• Grid Network of Infrastructure for the
  Generation, Transmission, Distribution of
  electricity. Operated by Utility Companies, 3rd
  Party Providers Regulatory Agencies.
• Interconnection Parallel connection to the
  Grid. Requires Utility approval.

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Key Process Related Definitions

• kW Kilowatt. 1,000 watts. Measurement of Power
  in terms of Generation Capacity or Load.
• kWAC AC peak power rating of PV system after
  de-rating factors are calculated.
• kWDC DC power rating of PV system. May be
  stated in terms of STC (Standard Test Conditions)
  or PTC (Performance Test Conditions).
• kWH Kilowatthour. 1,000 Watthours. Measurement
  of Power Generated or Consumed over time. This is
  how you buy your electricity from the Utility
  Company. (Equal to 1000 Watts continuous for 1
  hour or 100 Watts coninuous for 10 hours.)

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Key Process Related Definitions

• kWDC DC power rating of PV system. May be
  stated in terms of STC (Standard Test Conditions)
  or PTC (Performance Test Conditions).
• kWH Kilowatthour. 1,000 Watthours. Measurement
  of Power Generated or Consumed over time. This is
  how you buy your electricity from the Utility
  Company. (Equal to 1000 Watts continuous for 1
  hour or 100 Watts coninuous for 10 hours.)
• Net-Metering Allows excess energy produced by
  grid-tied PV systems to flow in reverse, back
  through the utility meter, and "banked" for later
  use. Energy generated is valued at retail.
  value depends on electric service rate of
  account. Reconciled or settled annually in CA.

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Key Process Related Definitions

• PV Production Electricity generated by a PV
  System. May be stated in terms of kW (Point in
  time power) or kWH (Power produced in a given
  period of time).
• Production Based Incentive (PBI) Distribution
  of incentive funds based on actual kWH production
  of PV system. Not yet effectively deployed in
  the US. Stay tuned! This is where it all has
  to go if its gonna work for the future

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Key Process Related Definitions

• PTC Performance Test Conditions. Testing
  standard for modules that was developed to more
  closely represent conditions likely to be found
  in the field. 1000 W/M2, 20C Ambient Temp. (AKA
  PVUSA Test Conditions)
• STC Standard Test Conditions. Laboratory
  testing standard for modules. 1000 W/M2, 25C
  Cell Temp. Nameplate Rating of Module or Array.
  Manufacturers advertise and sell modules based on
  this value. (AKA Peak Power Rating)

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Key Equipment Related Definitions

• AC Alternating Current. Form of electricity
  supplied by Utility Company.
• DC Direct Current. Form of electricity
  generated by PV modules.
• Combiner Circuit Termination Equipment that
  connects multiple PV Source Circuits, generally
  in Parallel. Has fuses or breakers for
  overcurrent protection of individual circuits.

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Key Equipment Related Definitions

• Disconnect Switch. Turns electrical circuit on
  off.
• Inverter Converts DC to AC.
• Module An individual assembly of PV cells.
  Often called a panel by unfamiliar folks.
• Panel A Mechanically connected assembly of
  Modules.

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Key Module Specification Related Definitions
Pay Attention! Things may not be what they
seem and not everybody speaks the same
language!!!!

• Voc Open Circuit Voltage at STC.
• Vpeak (Vmpp) Voltage at Maximum Power Point at
  STC.
• Isc Short Circuit Current (Amps) at STC.
• Ipeak (Impp) Amperage at Maximum Power Point at
  STC.

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Key Module Specification Related Definitions
Pay Attention! Things may not be what they
seem and not everybody speaks the same
language!!!!

• Max Power (Wpeak) Watts at STC.
• Max DC Short Circuit Current Maximum Array Isc
  at STC.
• UL 1703 Standard for establishing safety
  related suitability of flat plate photovoltaic
  modules.

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Key Inverter Specification Related Definitions
Pay Attention! Things may not be what they
seem and not everybody speaks the same
language!!!!

• DC Voltage Range Minimum to Maximum DC Voltage
  Input for the Inverter to operate. Array must be
  electrically connected to provide voltage in this
  range.
• Output Power Rated AC output capacity in Watts.
• AC Voltage Range Minimum to Maximum AC Voltage
  Input for the Inverter to operate. Grid Voltage.
• Efficiency Efficiency of the DC-AC conversion
  in terms of watts. Ratings are based on X of
  capacity.

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Key Inverter Specification Related Definitions
Pay Attention! Things may not be what they
seem and not everybody speaks the same
language!!!!

• Maximum Input Current Maximum current of the
  Array at Max Power Point.
• Max DC Short Circuit Current Maximum Array Isc.
• UL 1741 / IEEE 929 Standards for establishing
  suitability for Grid Connection of the Inverter.

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Key Secondary Component Related Definitions

• BOS Balance of System. Equipment hardware
  required to build a PV system other than Modules
  Inverters.
• AC Disconnect Switch in the AC Circuit.
  Disconnects AC source from Inverter. May be
  integral or external to Inverter. Multiple AC
  Disconnects are often required.
• DC Disconnect Switch in the DC Circuit.
  Disconnects DC source from Inverter. May be
  integral or external to Inverter.

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Key Secondary Component Related Definitions

• PV Meter Generation meter. Measures output of
  PV System over time. AKA REC Meter
• Rack Framework supporting and mechanically
  connecting Modules.