powerpoint ® presentation photovoltaic systems cells, modules, and arrays photovoltaic cells...

PowerPoint® PresentationPowerPoint® Presentation

Photovoltaic SystemsPhotovoltaic SystemsCells, Modules, and ArraysCells, Modules, and Arrays

Photovoltaic Cells • Current–Voltage (I–V) Curves • PV Device Response •

Modules and Arrays

Arizona Solar Power Societywww.meetup.com/arizona-solar-power-society/

Photovoltaic Cells • Current–Voltage (I–V) Curves • PV Device Response •

Modules and Arrays

Arizona Solar Power Societywww.meetup.com/arizona-solar-power-society/

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

The basic building blocks for PV systems include cells, modules, and arrays.

The basic building blocks for PV systems include cells, modules, and arrays.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Semiconductor materials with special electrical properties can be made by adding small amounts of other elements to silicon crystals.

Semiconductor materials with special electrical properties can be made by adding small amounts of other elements to silicon crystals.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

The photovoltaic effect produces free electrons that must travel through conductors in order to recombine with electron voids, or “holes.”

The photovoltaic effect produces free electrons that must travel through conductors in order to recombine with electron voids, or “holes.”

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Various PV materials and technologies produce different efficiencies.Various PV materials and technologies produce different efficiencies.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Monocrystalline silicon wafers are sawn from grown cylindrical ingots.

Monocrystalline silicon wafers are sawn from grown cylindrical ingots.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Polycrystalline silicon wafers are sawn from cast rectangular ingots.

Polycrystalline silicon wafers are sawn from cast rectangular ingots.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Several steps are involved in turning silicon wafers into PV cells.

Several steps are involved in turning silicon wafers into PV cells.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Diffusion of phosphorous gas creates a thin n-type semiconductor layer over the entire surface of a p-type wafer.

Diffusion of phosphorous gas creates a thin n-type semiconductor layer over the entire surface of a p-type wafer.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

The different materials, processes, and manufacturing steps produce a range of PV cell types.

The different materials, processes, and manufacturing steps produce a range of PV cell types.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

An I-V curve illustrates the electrical output profile of a PV cell, module, or array at a specific operating condition.

An I-V curve illustrates the electrical output profile of a PV cell, module, or array at a specific operating condition.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Open-circuit voltage is easily measured with test instruments.

Open-circuit voltage is easily measured with test instruments.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Using in-line and clamp-on ammeters are two methods of measuring short-circuit current.

Using in-line and clamp-on ammeters are two methods of measuring short-circuit current.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

A power versus voltage curve clearly shows the maximum power point.

A power versus voltage curve clearly shows the maximum power point.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Fill factor represents the shape of an I-V curve.Fill factor represents the shape of an I-V curve.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Efficiency is a measure of how effectively a PV device converts solar power to electrical power.

Efficiency is a measure of how effectively a PV device converts solar power to electrical power.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

A PV device can be modeled by a current source in parallel with a diode, with resistance in series and parallel.

A PV device can be modeled by a current source in parallel with a diode, with resistance in series and parallel.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Increasing series resistance in a PV system flattens the knee in the I-V curve, reducing maximum power, fill factor, and efficiency.

Increasing series resistance in a PV system flattens the knee in the I-V curve, reducing maximum power, fill factor, and efficiency.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Decreasing shunt resistance reduces fill factor and efficiency and lowers maximum voltage, current, and power, but it does not affect short-circuit current.

Decreasing shunt resistance reduces fill factor and efficiency and lowers maximum voltage, current, and power, but it does not affect short-circuit current.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Voltage increases rapidly up to about 200 W/m2, and then is almost constant. Current and maximum power increase proportionally with irradiance.

Voltage increases rapidly up to about 200 W/m2, and then is almost constant. Current and maximum power increase proportionally with irradiance.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Increasing cell temperature decreases voltage, slightly increases current, and results in a net decrease in power.

Increasing cell temperature decreases voltage, slightly increases current, and results in a net decrease in power.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Modules are constructed from PV cells that are encapsulated by several layers of protective materials.

Modules are constructed from PV cells that are encapsulated by several layers of protective materials.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

An array is a group of PV modules integrated as a single power-generating unit.

An array is a group of PV modules integrated as a single power-generating unit.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Several modules may be connected together to form a panel, which is installed as a preassembled unit.

Several modules may be connected together to form a panel, which is installed as a preassembled unit.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

A junction box on the back of a module provides a protected location for electrical connections and bypass diodes.

A junction box on the back of a module provides a protected location for electrical connections and bypass diodes.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

PV cells or modules are connected in series strings to build voltage.

PV cells or modules are connected in series strings to build voltage.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

The overall I-V characteristics of a series string are dependent on the similarity of the current outputs of the individual PV devices.

The overall I-V characteristics of a series string are dependent on the similarity of the current outputs of the individual PV devices.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Strings of PV cells or modules are connected in parallel to build current.Strings of PV cells or modules are connected in parallel to build current.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

The overall I-V curve of PV devices in parallel depends on the similarity of the current outputs of the individual devices.

The overall I-V curve of PV devices in parallel depends on the similarity of the current outputs of the individual devices.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Modules are available in several sizes and shapes, including squares, rectangles, triangles, flexible units, and shingles.

Modules are available in several sizes and shapes, including squares, rectangles, triangles, flexible units, and shingles.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Bypass diodes allow current to flow around devices that develop an open-circuit or high-resistance condition.

Bypass diodes allow current to flow around devices that develop an open-circuit or high-resistance condition.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

A bypass diode limits reverse current through PV devices, preventing excessive power loss and overheating.

A bypass diode limits reverse current through PV devices, preventing excessive power loss and overheating.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Module labels must include performance ratings for the module and may include other information used to design a PV system.

Module labels must include performance ratings for the module and may include other information used to design a PV system.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Various test conditions can be used to evaluate module performance and may produce different results.

Various test conditions can be used to evaluate module performance and may produce different results.

Chapter 5 — Cells, Modules, and ArraysChapter 5 — Cells, Modules, and Arrays

Modules are added in series to form strings or panels, which are then combined in parallel to form arrays.

Modules are added in series to form strings or panels, which are then combined in parallel to form arrays.