Shawn Murphy
September 29, 2011
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Solar Photovoltaics
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Electricity Generation, the CEC and PUC
Silicon Solar Cell production
Technical challenges of grid-tied solar
Grid-tied issues
Permitting and Rebates
Net Metering
Design issues
Solar Engineering as a Career
◦ General class recommendations
◦ Training on solar PV
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
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There is no good way to store electricity
Batteries
Peak energy is more expensive and more
polluting
Energy produced during high demand periods
is more valuable
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
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California Energy Commission
Founded early 70’s
CEC goals
◦ Generate power using alternative means
◦ Generate power during peak hours
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Public Utilities Commission
Regulate public utilities like PG&E, SCE and SDG&E
Tells utilities what they can charge for electricity
Decoupled utility profits from electricity generation
Shawn Murphy, PE • ENGR10 Guest Speaker
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Similar process as semiconductor manufacturing.
Conventional silicon still dominates market
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
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Much simpler than battery-based system.
Grid serves as free, infinitely-large, nomaintenance battery
System sizing not as crucial
Can be designed to maximize yearly annual
electricity generation. Does not have to be
optimized for winter production.
Can operate at much higher voltages, saving
power losses.
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
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CEC goals
◦ Generate power during peak hours
◦ Generate power using alternative means
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Grid connected solar photovoltaic
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Maximum generation during sunny summer days
Distributed generation
Uses existing spaces
Very quick deployment
Shawn Murphy, PE • ENGR10 Guest Speaker
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Power Quality
Safety
Connection to Existing Equipment
Shawn Murphy, PE • ENGR10 Guest Speaker
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How do you keep track of the power?
How much do you pay for the power?
How do you take into account when the
power is produced?
How do you determine the rebate amount?
How do you incentivize grid-connected solar
at the proper amount over time?
How often do you read the meter?
Who inspects the system?
Shawn Murphy, PE • ENGR10 Guest Speaker
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One single meter that spins forward and
backwards.
Meter can take into account time of use rates
Annual true-up
Minimum monthly meter fee, $4 to $13,
charged by utility
Shawn Murphy, PE • ENGR10 Guest Speaker
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Tax Credits and deductions
◦ 30% FITC
◦ MACRS depreciation
◦ Various state tax breaks
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Renewable Energy Credits
State Rebates
California Solar Initiative
◦ Declining schedule – based on expected
performance
Shawn Murphy, PE • ENGR10 Guest Speaker
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Must know how much a customer is paying for
electricity
How do you compare one-time cost of a solar
system versus the value of lower electricity bills in
future years?
Engineering economics
◦ Payback
◦ Net Present Value
◦ Internal Rate of Return
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
Shawn Murphy, PE • ENGR10 Guest Speaker
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Engineering Economics
Accounting
Technical Writing
Public Speaking
Engineering Statistics
Computer Drafting/ CAD
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Google Sketchup
Autocad
Solidworks
Pro-E
Shawn Murphy, PE • ENGR10 Guest Speaker
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PG&E Energy Center
Diablo Valley College
Private classes
◦ Solar Living Institute
◦ Solar Power International
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Semicon – Intersolar SF July
Shawn Murphy, PE • ENGR10 Guest Speaker