1 / 112

Photovoltaic Design and Installation

Photovoltaic Design and Installation . Bucknell University Solar Scholars Program . Presenters: Barbara Summers ’11 Brian Chiu ‘11. Outline . Why Renewable Energy? The Science of Photovoltaics System Configurations Principle Design Elements Energy Efficiency

jerrod
Télécharger la présentation

Photovoltaic Design and Installation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Photovoltaic Design and Installation Bucknell University Solar Scholars Program Presenters: Barbara Summers ’11 Brian Chiu ‘11

  2. Outline • Why Renewable Energy? • The Science of Photovoltaics • System Configurations • Principle Design Elements • Energy Efficiency • The Solar Scholars program at Bucknell (walking tour)

  3. What’s wrong with this picture? • Pollution from burning fossil fuels leads to an increase in greenhouse gases, acid rain, and the degradation of public health. • In 2005, the U.S. emitted 2,513,609 metric tons of carbon dioxide, 10,340 metric tons of sulfur dioxide, and 3,961 metric tons of nitrogen oxides from its power plants.

  4. 40% 85% of our energy consumption is from fossil fuels!

  5. Why Sustainable Energy Matters • The world’s current energy system is built around fossil fuels • Problems: • Fossil fuel reserves are ultimately finite • Two-thirds of the world' s proven oil reserves are locating in the Middle-East and North Africa (which can lead to political and economic instability)

  6. Why Sustainable Energy Matters • Detrimental environmental impacts • Extraction (mining operations) • Combustion • Global warming (could lead to significant changes in the world' s climate system, leading to a rise in sea level and disruption of agriculture and ecosystems)

  7. Making the Change to Renewable Energy • Solar • Geothermal • Wind • Hydroelectric

  8. Today’s Solar Picture Financial Incentives • Investment subsidies: cost of installation of a system is subsidized • Net metering: the electricity utility buys PV electricity from the producer under a multiyear contract at a guaranteed rate • Renewable Energy Certificates ("RECs")

  9. Solar in Pennsylvania • Pennsylvania is in fact a leader in renewable energy • Incentives • Local & state grant and loan programs • Tax credits & deductions • REC’s (in 2006: varied from $5 to $90 per MWh, median about $20)

  10. PA Alternative Energy Investment Fund • $650 Million for Renewable Energy and Energy Efficiency • The Pennsylvania Sunshine Program • provide $180 million in grants to Commonwealth homeowners and small businesses to purchase and install solar photovoltaic (PV) and solar hot water systems.

  11. Deregulation and Grid Parity • Current cost of electricity - 8.58 cents/kWh • 2010 PA electricity prices will be uncapped • Est. 33+% increase projected by PPL • The Solar America Initiative • goal of bringing solar to grid parity by 2015

  12. Electricity

  13. The Idea ≈

  14. The Idea

  15. The Idea

  16. Terminology • Voltage • Measured in Volts • Electrical potential • “Height” of water on one side of a dam compared to the other side • Current • Measured in Amps • Rate of electron flow • “Speed” at which water flows through the dam

  17. Terminology • Resistance • The opposition of a material to the flow of an electrical current • Depends on • Material • Cross sectional area • Length • Temperature

  18. Types of Current • DC = Direct Current • PV panels produce DC • Batteries store DC • AC = Alternating Current • Utility power • Most consumer appliances use AC • Electric charge changes direction

  19. Terminology • Watt • Measure of Power • Rate of electrical energy • Not to be confused with Current!

  20. Typical Wattage Requirements

  21. Terminology • Watt-hour (Wh) is a measure of energy • Unit quantity of electrical energy (consumption and production) • Watts x hours = Watt-hours • 1 Kilowatt-hour (kWh) = 1000 Wh

  22. Symbols and Units Voltage: E or V (Volts) Current: I or A (Amps) Resistance: R or Ω (Ohms) Watt: W (Watt)

  23. Grid-Tied System Overview

  24. Harnessing the Sun

  25. Advantages Easy to install (less components) Grid can supply power Disadvantages No power if grid goes down Grid-Tied System

  26. Solar Modules

  27. Solar Domestic Hot Water

  28. Solar Domestic Hot Water

  29. Photovoltaic (PV) Hierarchy • Cell < Module < Panel < Array

  30. Inside a PV Cell

  31. Available Cell Technologies • Single-crystal or Mono-crystalline Silicon • Polycrystalline or Multi-crystalline Silicon • Thin film • Ex. Amorphous silicon or Cadmium Telluride

  32. Monocrystalline Silicon Modules • Most efficient commercially available module (11% - 14%) • Most expensive to produce • Circular (square-round) cell creates wasted space on module

  33. Polycrystalline Silicon Modules • Less expensive to make than single crystalline modules • Cells slightly less efficient than a single crystalline (10% - 12%) • Square shape cells fit into module efficiently using the entire space

  34. Amorphous Thin Film • Most inexpensive technology to produce • Metal grid replaced with transparent oxides • Efficiency = 6 – 8 % • Can be deposited on flexible substrates • Less susceptible to shading problems • Better performance in low light conditions that with crystalline modules

  35. Selecting the Correct Module • Practical Criteria • Size • Voltage • Availability • Warranty • Mounting Characteristics • Cost (per watt)

  36. Current-Voltage (I-V) Curve

  37. Effects of Temperature • As the PV cell temperature increases above 25º C, the module Vmp decreases by approximately 0.5% per degree C

  38. Effects of Shading/Low Insolation • As insolation decreases amperage decreases while voltage remains roughly constant

  39. Shading on Modules • Depends on orientation of internal module circuitry relative to the orientation of the shading. • SHADING can half or even completely eliminate the output of a solar array!

  40. Tools Surface Temperature Insolation Pyranometer Laser Thermometer

  41. PV Wiring

  42. Series Connections • Loads/sources wired in series • VOLTAGES ARE ADDITIVE • CURRENT IS EQUAL

  43. Parallel Connections • Loads/sources wired in parallel: • VOLTAGE REMAINS CONSTANT • CURRENTS ARE ADDITIVE

  44. Wiring Introduction • Should wire in Parallel or Series?

  45. Wire Components • Conductor material = copper (most common) • Insulation material = thermoplastic (most common) • Wire exposed to sunlight must be classed as sunlight resistant

  46. Color Coding of Wires • Electrical wire insulation is color coded to designate its function and use

  47. Cables and Conduit • Cable: two or more insulated conductors having an overall covering • Conduit: metal or plastic pipe that contains wires

More Related