ENERGY FROM THE SUN SOLAR PHOTOVOLTAIC TECHNOLOGIES EDUCATION

ENERGY FROM THE SUN SOLAR PHOTOVOLTAIC TECHNOLOGIES EDUCATION MODULE (SPV 01 PP) CACTUS MOON EDUCATION, LLC www. cactusmooneducation. com _____________ © Cactus Moon Education, LLC.

INDEX • Slide 1 Front Sheet • Slide 2 Index • Slide 3 The Photovoltaic Solar Cell • Slide 4 How a Solar Cell is Formed • Slide 5 How a Solar Cell Works • Slide 6 The Photovoltaic Module • Slide 7 The Inverter • Slide 8 Solar Photovoltaic Technologies • Slide 9 Flat Plate PV • Slide 10 HCPV • Slide 11 Thin film PV • Slide 12 A PV Solar System _____________ © Cactus Moon Education, LLC.

The Photovoltaic Cell • The basic building block of a photovoltaic solar/electric system is the Photovoltaic cell, or solar cell. • The most common material used to make a solar cell is silicon. • The silicon is heated in a furnace out of which a single crystal ingot is drawn. • The ingot is sliced into wafers to be processed into a solar cell. _____________ © Cactus Moon Education, LLC.

How a Solar Cell is Formed 1 2 The Silicon wafer is “doped” on one side with a Ptype material such as Phosphorus The wafer is then doped on the other side with an N-type material such as Boron N-Type Silicon Wafer P-Type 3 At the junction of the P and N type areas a “depletion” layer forms 4 A top electrode array and an aluminum backplate are added to the wafer _____________ © Cactus Moon Education, LLC.

How a Solar Cell Works 1 2 The electronic charges within the doped material create an electric field across the depletion layer When sunlight strikes the cell it can knock an electron out of its atomic orbit + - 3 4 + e+ - + + + - - - The electric field sweeps the electron towards the top electrodes The gap or “hole” left by the electron is swept to wards the back plate _____________ © Cactus Moon Education, LLC. 5 The flow of charges makes an electric current which powers the attached electric circuit Cactus Moon Education, LLC.

The Photovoltaic Module The output voltage of a silicon photovoltaic cell is approximately 0. 7 Volts. Multiple cells are connected together to make a photovoltaic module. _____________ © Cactus Moon Education, LLC.

The Inverter • The electricity generated by a photovoltaic module is Direct Current or DC. • Most electrical appliances use Alternating Current or AC. • Electronic circuits in an Inverter turn the DC power into AC power. _____________ © Cactus Moon Education, LLC.

Solar Photovoltaic Technologies • Photovoltaic modules can be manufactured and used in a number of different ways. • The Flat Plate PV module is the most common and is the one shown in the previous slides. • High Concentration PV or HCPV uses a lens or a mirror to capture the solar energy and concentrate it onto a solar cell. • Thin Film solar cells are manufactured by evaporating very thin layers of the photovoltaic material onto a glass or plastic backing. _____________ © Cactus Moon Education, LLC.

Flat Plate PV • Flat Plate PV modules are the most commonly used. • They are manufactured from single crystals or multiple crystals of silicon. • Flat Plate PV modules can typically convert 14% of the incident sun’s energy into electricity. _____________ © Cactus Moon Education, LLC.

HCPV • Instead of covering a large area with photovoltaic material, HCPV harvests the sun’s energy using a relatively cheap plastic lens or a glass mirror. • The solar energy is then “concentrated” onto a small piece of photovoltaic material. • HCPV systems can convert between 20% and 40% of the incident solar energy into electricity. _____________ © Cactus Moon Education, LLC.

Thin Film PV • Thin Film PV cells are manufactured by coating a glass or plastic sheet with a very thin layer of photovoltaic material atoms. • Large areas of glass or plastic can be covered using this technique. • Thin film PV modules can typically convert 9% of the incident solar energy into electricity. _____________ © Cactus Moon Education, LLC.

A PV Solar System A complete residential PV Solar System contains several components. 1 PV modules 2 DC disconnect switch 3 Inverter 1 7 Solar generation meter 4 5 2 4 5 3 6 AC disconnect switch 6 _____________ © Cactus Moon Education, LLC. House service entrance 7 Utility k. Wh meter Cactus Moon Education, LLC.