Title: Freshman Clinic
1Freshman Clinic
2Wind PV Production (96-03)
Wind production PV production
3Wind Grows Another 20 in 04
4PV Market Keeps Growing in 04
5NJ Wind Resources
6Wind Turbines
7Wind Turbines
- A wind turbine obtains its power input by
converting the force of the wind into a torque
acting on the rotor blades. - The amount of energy which the wind transfers to
the rotor depends on the density of the air, the
rotor area, and the wind speed.
8Wind Turbines
- A wind turbine will deflect the wind before it
even reaches the rotor plane which means that all
of the energy in the wind cannot be captured
using a wind turbine.
9Wind Turbine Energy
- The annual energy delivered by a wind turbine can
be estimated by using the equation
The cost of electricity will vary with wind
speed. The higher the average wind speed, the
greater the amount of energy, and the lower the
cost of electricity
10Wind Power Classifications
11Delaware Bay / Coastal Wind Speeds
- Areas along shore or in mountains may be ideal
for wind power - Wind speeds as low as
- 4.5 -5.5 m/s
- for res farms/comm
- gt6.0 m/s can be used
- for power farms
- At 6.5 m/s, electricity can be below
- 0.07/kWh
True Wind Solutions
122005 NJCEP Rebates
- Wind and Sustainable Biomass Systems
- Systems lt 10 kW 5.00/watt
- Maximum incentive (60 of system costs)
- Systems gt 10kW
- First 10 kW 3.00/watt
- gt 10 to 100 kW 2.00/watt
- gt 100 to 500 kW 1.50/watt
- gt 500 kW, up to 1000 kW 0.15/watt
- Maximum incentive (30 of system costs)
13Sample 10 kW Turbine in NJ
- Class 3 winds at ground 5.5 m/s, 24 m (80ft)
6.3 m/s aloft - Power generated is 18,000 kWh/year
- Turbine 24,750
- Tower 6,800
- Install/Misc 5,500
- NJCEP Rebate (60) 22,230
- Net Cost 14,820
- 15 year electric cost 5.5/kWh
- Simple Payback 7.5 years
14New Jersey Anemometer Loan Program
- USDOE, NJBPU/NJCEP, Rutgers and Rowan University
have partnered to offer free wind energy analysis
to farms seriously considering wind - 1 year onsite wind measurement
- Tower and anemometer installed at no charge
- Contacts
- NJCEP Alma Rivera 1.973-648-7405 or email
alma.rivera_at_bpu.state.nj.us - Rowan Dr. Peter Mark Jansson 1.856.256.5373 or
email jansson_at_rowan.edu - Rutgers Dr. Michael R. Muller 1.732.445.3655 or
email muller_at_caes.rutgers.edu
15New Jersey Anemometer Loan Program
- Regional Data from the South Available OnLine
- http//www.rowan.edu/cleanenergy
- UNDER CONSTRUCTION
16New Jersey Wind Power
17Solar Resources - Direct Beam
18Solar Resources Total Diffuse
19Historic PV price/cost decline
- 1958 1,000 / Watt
- 1970s 100 / Watt
- 1980s 10 / Watt
- 1990s 3-6 / Watt
- 2000-2006
- 1.8-2.5/ Watt (cost)
- 3.50-4.75/ Watt (price)
20PV cost projection
- 1.50 ? 1.00 / Watt
- 2007 ? 2008
- SOURCE US DOE / Industry Partners
21Solar PV - Practical Information
- Approx South Facing Roof or field
- Roof angles from 20-50 degrees
- Less than 200 from loads
- Every 70 square feet of area can yield up to 1000
kWh per year in New Jersey
22PV technology efficiencies
- 1970s/1980s ? 2003 (best lab efficiencies)
- 3 ? 13 amorphous silicon
- 6 ? 18 Cu In Di-Selenide
- 14 ? 20 multi-crystalline Si
- 15 ? 24 single crystal Si
- 16 ? 37 multi-junction concentrators
23Amorphous Si
24Amorphous Si
25Cadmium Telluride
26Multi-crystalline Si
27Multi-crystalline Si
28Single Crystal Si
29Semi-Conductor Physics
- PV technology uses semi-conductor materials to
convert photon energy to electron energy - Many PV devices employ
- Silicon (doped with Boron for p-type material or
Phosphorus to make an n-type material) - Gallium (31) and Arsenide (33)
- Cadmium (48) and Tellurium (52)
30p-n junction
- When junction first forms as the p and n type
materials are brought together mobile electrons
drift by diffusion across it and fill holes
creating negative charge, and in turn leave an
immobile positive charge behind. The region of
interface becomes the depletion region which is
characterized by a strong E-field that builds up
and makes it difficult for more electrons to
migrate across the p-n junction.
31Depletion region
- Typically 1 µm across
- Typically 1 V
- E-field strength gt 10,000 V/cm
- Common, conventional p-n junction diode
- This region is the engine of the PV Cell
- Source of the E-field and the electron-hole
gatekeeper
32Bandgap energy
- That energy which an electron must acquire in
order to free itself from the electrostatic
binding force that ties it to its own nucleus so
it is free to move into the conduction band and
be acted on by the PV cells induced E-field
structure.
33Band Gap (eV) and cutoff Wavelength
- PV Materials Band Gap Wavelength
- Silicon 1.12 eV 1.11 µm
- Ga-As 1.42 eV 0.87 µ m
- Cd-Te 1.5 eV 0.83 µ m
- In-P 1.35 eV 0.92 µ m
34Photons have more than enough or not enough
energy
- Sources of PV cell losses (?15-24)
- Silicon based PV technology max(?)49.6
- Photons with long wavelengths but not enough
energy to excite electrons across band-gap (20.2
of incoming light) - Photons with shorter wavelengths and plenty
(excess) of energy to excite an electron (30.2
is wasted because of excess - Electron-hole recombination within cell (15-26)
35p-n junction
- As long as PV cells are exposed to photons with
energies exceeding the band gap energy
hole-electron pairs will be created - Probability is still high they will recombine
before the built-in electric field of the p-n
junction is able to sweep electrons in one
direction and holes in the other
36Generic PV cell
Incoming Photons
Top Electrical Contacts
electrons ?
- - - - Accumulated Negative Charges - - - -
n-type
Holes
E-Field
Depletion Region
- - - - - -
- - -
Electrons
p-type
Accumulated Positive Charges
Bottom Electrical Contact
I ?
37PV Module Performance
- Standard Test Conditions
- 1 sun 1000 watts/m2 1kW/m2
- 25 oC Cell Temp
- AM 1.5 (Air Mass Ratio)
- I-V curves
- Key Statistics VOC, ISC, Rated Power, V and I at
Max Power
38PV specifications (I-V curves)
- I-V curves look very much like diode curve
- With positive offset for a current source when in
the presence of light
39From cells to modules
- Primary unit in a PV system is the module
- Nominal series and parallel strings of PV cells
to create a hermetically sealed, and durable
module assembly - DC (typical 12V, 24V, 48V arrangements)
- AC modules are available
40PV Module Performance
- Temperature dependence
- Nominal operating cell temperature (NOCT)
Tc cell temp, Ta ambient temp (oC), S
insolation kW/m2
41PV Output deterioration
- Voc drops 0.37/oC
- Isc increases by 0.05/oC
- Max Power drops by 0.5/oC
42BP 3160
- Rated Power 160 W
- Nominal Voltage 24V
- V at Pmax 35.1
- I at Pmax 4.55
- Min Warranty 152 W
- NOTE I-V Curves
43From modules to arrays
- Method
- First Determine Customer Needs (reduce)
- Determine Solar Resource (SP, model, calcs)
- Select PV Modules or
- Select DC-AC Inverter
- Look for Maximum Power Tracking Window
- Max DC voltage Current
- Assure Module Strings Voc and Isc meet inverter
specifications
44See Mesa Environmental Solar Audits
- Spreadsheet Customer Monthly Consumption
- Determine potential Shade Free Sites
- ID source for local Solar Resource Info
- Model (PVWATTS, PV FCHART, NJCEP)
- Weather Service Data
- Actual measurements from region
45Remember
- PV modules stack like batteries
- In series Voltage adds,
- constant current through each module
- In parallel Current adds,
- voltage of series strings must be constant
- Build Series strings first, then see how many
strings you can connect to inverter
46Match Modules With Inverter
- Find Optimal Fit of Series Strings
- TO BE IN MAX POWER TRACKING WINDOW
- Assure module s do not exceed Voc
- Find Optimal of Strings in Parallel
- TO MEET MODULE POWER RATING
- CURRENT TO BE LESS THAN MAX Isc
- Are Modules and Inverter a good match?
- Overall Hardware Utilization efficiency
47Putting it all Together
- Customer Needs (energy usage ? reduce)
- PV System Design Requirements
- Solar Resource Assessment
- Potential Sites on Customer Property
- PV Module Inverter Selection
- Wiring Diagram
- System Economic Analysis
48Wiring the System
49PV system types
- Grid Interactive and BIPV
- Stand Alone
- Pumping
- Cathodic Protection
- Battery Back-Up Stand Alone
- Medical / Refrigeration
- Communications
- Rural Electrification
- Lighting
50Grid Interactive
51Grid-interactive roof mounted
52Building Integrated PV
53Stand-Alone First House
54Remote
55NJ Incentives
- NJ Clean Energy Program
- 70 rebate for grid connected systems up to 10kW
- Smaller rebates for increments above 10kW
- Net Metering to 100kW
- Solar Renewable Energy Certificates
- NJ RPF requires 2 MW 2004 ? 10 MW 2008
- Currently trading about 200/MWh
56Economic / Market Impacts
- Systems would have 25-30 year payback
- With NJCEP reduces to 10 year
- With SREC could be less than 7 year