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Solar PowerPoint - Introduction To Solar Energy

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					What is Solar Energy?
          1st LAW OF
    THERMODYNAMICS:
Energy can be neither created nor
destroyed, but only transformed.
             Solar Energy
Example: You have electricity available at your
house. If you plug a lamp into an receptacle, the
energy is converted from electricity to light and
heat. We convert energy from a variety of forms
into forms we can more easily use.
  So….What Is Solar Energy?


SOLAR ENERGY is energy from the sun that
 is converted into thermal or electrical energy.
Solar Thermal
What is THERMAL?
         THERMAL refers to HEAT

Some similar words:
 Thermos
 Thermometer
 Therm(s): A measurement of heat, often
  associated with natural gas.
 British Thermal Units (BTU’s): The amount of
  heat needed to raise one pound of water one
  degree Fahrenheit.
SOLAR THERMAL, in this context, is
the practice of using the sun’s energy to
 produce heat, typically applied to water
             or other liquids.
       History: Solar Thermal

This is the first practical
application of solar
thermal. It is basically a
series of wooden boxes
with glass tops known as
a ‘hot box.’ Any idea
when it was built?
          History: Solar Thermal
   The first practical application of solar thermal in
    Western history was built by a Swiss inventor,
    Horace de Saussure, in 1767. It was an insulated
    box with a glass top and two smaller boxes
    inside. When exposed to the sun, the bottom
    box heated to 228 degrees Fahrenheit. This has
    been the prototype for millions of solar water
    heaters, even many being built today.
         History: Solar Thermal
   A steam engine was invented in 1861 that was
    powered entirely by the sun.
   Also in the 19th century, European scientists
    developed collectors that could boil ammonia to
    perform work such as locomotion and
    refrigeration.
   The parabolic trough collector was also
    developed in the 19th century. The same basic
    design is still used today.
          History: Solar Thermal
   During the 19th century, in areas of the nation
    w/ few natural resources, many industrious
    Americans used large metal tanks to heat water
    by using energy from the sun.
History: Solar Thermal
           History: Solar Thermal
   The first solar thermal
    system was patented in
    1891 by a man named
    Clarence Kemp.
         History: Solar Thermal
   By 1897 one third of the homes in Pasadena, CA
    had water heated by solar thermal systems.
   By 1918 another manufacturer had sold over
    4,000 solar water heaters.
   By 1941, over half the homes in Florida had
    solar water heaters.
          History: Solar Thermal
   Q: Are at least a third of Pasadena’s homes still
    using solar to heat their water?
   Q: Are at least half of Florida’s homes still using
    solar thermal?
   Q: Why or why not?
        History: Solar Thermal
Q: What ultimately drives the solar thermal
 industry?
        History: Solar Thermal
Q: What ultimately drives the solar thermal
 industry?

A: Money

When solar costs more than other energy sources,
 solar goes away.
          History: Solar Thermal
   The discovery of natural gas in California in the
    1920’s drew an abrupt halt to the local solar
    thermal industry.
   After WWII, electricity rates dropped and
    stopped the solar thermal industry in Florida.
          History: Solar Thermal
   Japan doesn’t have an abundant source of coal,
    natural gas, or oil, so the cost of these energy
    sources encourages them to look elsewhere (to
    solar).
   In 1969 there were 4 million solar water heating
    tanks on Japanese homes. Today there are over
    10 million solar thermal systems being used.
   Solar thermal is used on 90% of homes in Israel.
Concentrating Solar Power (CSP)
There are many kinds of high-temperature
  commercial solar thermal systems. These
  systems take solar heat and use it to make
  electricity.
 Parabolic Trough

 Power Tower

 Dish Designs

 Fresnel Reflectors

 Fresnel Lens
Parabolic Trough
Parabolic Trough
Parabolic Trough
Parabolic Trough
              Parabolic Trough
   The parabolic trough was developed in the late
    1800s and patented in 1907.
   Parabolic Trough power plants use a curved
    trough which reflects the direct solar radiation
    onto a pipe containing a fluid (also called a
    receiver, absorber or collector) running the
    length of the trough, above the reflectors.
   These troughs track the sun on a single axis,
    from east to west.
              Parabolic Trough
   The receiver may be enclosed in a glass vacuum
    chamber. The vacuum significantly reduces
    convective heat loss.
   A fluid (also called heat transfer fluid) passes
    through the receiver and becomes very hot
    (around 400 degrees F). Common fluids are
    synthetic oil, molten salt and pressurized steam.
    The fluid containing the heat is transported to a
    heat engine where about a third of the heat is
    converted to electricity.
Parabolic Trough
              Parabolic Trough
   The world’s largest parabolic trough facility is in
    the Mojave Desert near Barstow and consists of
    nine plants for a total of 354 megawatts of peak
    output. The individual plants range from 14 to
    80 megawatts of capacity.
Parabolic Trough
Power Tower
Power Tower
                  Power Tower
   Power Towers (also known as 'central tower'
    power plants or 'heliostat' power plants) use an
    array of flat, moveable mirrors (called heliostats)
    to focus the sun's rays upon a collector tower
    (the receiver).
Power Tower
                 Power Tower
   The advantage of this design above the
    parabolic trough design is the higher
    temperature. Thermal energy at higher
    temperatures can be converted to electricity
    more efficiently and can be more cheaply stored
    for later use.
   The disadvantage is that each mirror must have
    its own dual-axis control, while in the parabolic
    trough design one axis can be shared for a large
    array of mirrors.
Power Tower
                 Power Tower
   The world's largest solar power tower plant is in
    Seville in Spain and is made up of more than
    1200 mirrored heliostats surrounding a huge 54
    story tower. This plant generates 20 megawatts
    of electricity, which is enough to supply 10,000
    homes.
Power Tower
Power Tower
Dish Designs
             Dish Designs
 A dish system uses a large, reflective, parabolic
dish (shaped like a satellite television dish). It
focuses all the sunlight that strikes the dish up
onto to a single point above the dish, where a
receiver captures the heat and transforms it into
a useful form. Typically the dish is coupled with
a Stirling engine in a Dish-Stirling System. From
there the energy is converted into electricity.
              Dish Design
 The advantage of a dish system is that it can
achieve much higher temperatures because of
the higher concentration of light (like the tower
designs). Higher temperatures leads to better
conversion to electricity.
                Dish Design
There are two main disadvantages:
 Heat to electricity conversion requires moving
  parts and that results in maintenance.
 The heavy engine is part of the moving
  structure, which requires a rigid frame and
  strong tracking system, which adds to the cost.
Fresnel Reflector
              Fresnel Reflectors
   A linear Fresnel reflector power plant uses a
    series of long, narrow, shallow-curvature (or flat)
    mirrors to focus light onto one or more linear
    receivers positioned above the mirrors. On top
    of the receiver a small parabolic mirror can be
    attached for further focusing the light.
Fresnel Reflector
Fresnel Reflector
Fresnel Lens
              Fresnel Lens
 The main advantage to this application is that
these lenses cost less than mirrors.
             Solar Thermal
Question: What do you do when the sun doesn’t
 shine?
             Heat Retention
Storage of heat is possible with solar thermal.
 Steam accumulator: condenses/pressurizes
  steam and maintains heat. Only one hour of
  storage currently available with this method.
 Molten salts: store energy up to one week in
  cold storage tanks.
 Graphite: newer option. Not a lot of info
  available on storage characteristics, yet.
        Low Temp Solar Thermal
   Residential Water Heating: used for
    consumption, cooking, bathing, recreation (hot
    tub, swimming pool), space heating and cooling
    (radiant floor systems, ducted systems), etc.
   These systems collect or absorb the sun’s light,
    which is then turned into heat, and that heat
    directly or indirectly heats water.
Low Temp Solar Thermal System
Low Temp Solar Thermal
Flat Plate Solar Thermal Collectors
            Flat Plate Collector
   The flat plate collector is the most common type
    of solar thermal collector.
   They use the basic concept Horace de Saussurre
    developed in 1767.
   Flat plate collectors do well in almost any
    environment and climate.
   Can heat water to 160 or 180 degrees
    Fahrenheit.
Flat Plate Collector
Evacuated Tube Collectors
Evacuated Tube Collectors
Evacuated Tube System
         Evacuated Tube System
   The vacuum in evacuated tubes helps reduce
    heat loss.
   Evacuated tubes have an ability to heat water to
    higher temperatures than other types of
    collectors, though over time a flat plate collector
    will typically produce more hot water between
    140 and 180 degrees F.
   Evacuated tubes are only needed when water
    must be heated above 180 degrees F.
Evacuated Tube Collectors
Batch Heater
Batch Heater
                 Batch Heater
   Batch heaters work on the thermo-siphon
    principle. As water is heated in the collector it
    rises to the top and is channeled into the holding
    tank. Cooler water moves into the bottom of
    the collector to take its place, which continues
    the cycle.
   Batch heaters can be susceptible to heat loss at
    night, reducing financial and energy gains.
Unglazed Polymer Collector
           Unglazed Collectors
   Unglazed collectors are commonly used for solar
    pool heating, but have recently been applied to
    domestic hot water systems.
   They are made of a polymer (a type of plastic)
    and are fairly inexpensive.
   They work best in Mediterranean climates and
    contribute heated water in the warm/hot
    summer months.
   They don’t do well in cold or windy
    environments.
Unglazed Collector
Unglazed Collector
             Solar Pool Heating
   Solar pool heating can be done with flat plate
    collectors, evacuated tubes, and unglazed
    collectors.
   Evacuated tube and flat plate collectors can’t
    have chlorine in them, so a heat exchanger must
    be used.
   Chlorinated water can run directly through
    unglazed collectors, making them more efficient
    at heating water in specific temperature ranges.
Solar Pool Heating
Solar Thermal - Commercial
 Solar Thermal - Commercial
Commercial & Industrial: Used in Restaurants,
Laundromats, heated aquatic centers, hotels,
apartment complexes, manufacturing facilities,
etc.
Solar Thermal - Commercial
Solar Thermal - Commercial
Solar Thermal - Commercial
Solar Thermal - Commercial
Solar Thermal
Passive Solar
               Passive Solar
Q: What is Passive Solar?
                Passive Solar
Q: What is Passive Solar?

A: Passive Solar technologies use sunlight for
  useful energy without use of active mechanical
  systems (like pumps, motors, tracking units, etc).
  These technologies convert sunlight into usable
  heat (water, air, thermal mass), cause air-
  movement for ventilating, or future use, with
  little use of other energy sources.
              Solar History
Greeks and Romans
used passive solar
designs to heat many of
their homes and
buildings in the cooler
months by facing an
opening or window to
the south. The Greek
city of Priene is
illustrated here.
                 Passive Solar
   Passive solar technologies include direct and
    indirect solar gain for space heating, solar water
    heating systems based on the thermosiphon, use
    of thermal mass and phase-change materials for
    slowing indoor air temperature swings, solar
    cookers, the solar chimney for enhancing natural
    ventilation, and earth sheltering.
Passive Solar
Trombe Wall
Trombe Wall
Solar Cooker
Earth Sheltering
Passive Solar
              Photovoltaics
Q: What are Photovoltaics (PV)?
               Photovoltaics
Q: What are Photovoltaics?

A: Photovoltaics is a field of technology that uses
  solar cells to convert sunlight directly into
  electricity.
PV System (Grid-Tied)
PV System (Off-Grid)
PV – Standalone
PV - Standalone
PV Components - Modules
Module Composition
         Typical Cell Efficiencies
   Monocrystalline cells = 14-20% efficient
   Poly or multi crystalline cells = 10-12% efficient
   Thin Film Photovoltaics = roughly 6% efficient
Mono Silicon Solar Module
Mono Silicon Solar Module
Solar Cell
Poly or Multi Silicon Module
Poly Silicon Cell
Poly or Multi Silicon Module
Thin Film PV Modules
Thin Film Solar
Thin Film Solar
PV Components - Inverters
PV Components - Inverters
PV Components - Inverters
PV Components - Inverters
PV Components - Inverters
PV Components - Inverters
PV Components - Inverters
Generator
Questions?

				
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