3. SOLAR ENERGY
Solar energy is radiant light and heat from the Sun that
is harnessed using a range of ever-evolving technologies
such as solar heating, photovoltaics, solar thermal
energy, solar architecture, molten salt power plants and
artificial photosynthesis.[1][2]
It is an important source of renewable energy and its
technologies are broadly characterized as either passive
solar or active solar depending on how they capture and
distribute solar energy or convert it into solar power.
Solar energy is any type of energy
generated by the sun.
4. TYPES OF SOLAR ENERGY
• Photovoltaic and
- Photovoltaic technology directly converts sunlight into electricity.
• Thermal
-Solar thermal technology harnesses its heat. These different technologies both tap the
Sun’s energy, locally and in large-scale solar farms.
Two different types of installations are used:
• Individual systems for homes or small communities. Photovoltaic panels can power
electrical devices, while solar thermal collectors can heat homes or hot water.
• Photovoltaic or concentrated solar power plants that cover hundreds of acres produce
electricity on a large scale, which can be fed into power grids.
5. HOW SOLAR ENERGY
ENTERS TO THE EARTH
Almost all of the Earth's energy input comes from the
sun. Not all of the sunlight that strikes the top of the
atmosphere is converted into energy at the surface of
the Earth. The Solar energy to the Earth refers to
this energy that hits the surface of the Earth itself.
The amount of energy that reaches the the Earth
gives a useful understanding of the energy for the
Earth as a system. This energy goes towards weather,
keeping the temperature of the Earth at a good level
for life and powers the entire biosphere. Additionally,
this solar energy can be used for solar power either
with solar thermal power plants or photovoltaic cells.
6. SOLAR ENERGY TO
THE EARTH
Energy from Sun to Earth
The Sun is generally considered to produce a constant amount of
power
with a surface intensity of , expressed in units of power per unit
area. As the Sun's rays spread into space this radiation becomes
less and less intense as an inverse square law.[1] The average
radiation intensity that hits the edge of the Earth's atmosphere is
known as the solar constant, or . Although this value is called a
constant it varies by about 7% between January 4th (perihelion),
when the Earth is closest to the sun, and July 4th (aphelion),
when the Earth is furthest away.[2] Therefore a yearly average is
used and is determined to be .[1] To determine this value from
solar flux, the distance from the Earth to the Sun is used. As well,
the total solar flux - not solar flux per unit area - must be
determined. Then the total solar flux from the Sun is divided by
the surface area of a sphere that has a radius equal to the
distance from the Earth to the Sun.
7. HOW IS SOLAR ENERGY STORED
• One of the drawbacks of solar energy systems is that the Sun
doesn't provide a constant stream of energy.On cloudy days or at
night, the amount of energy your system receives is reduced or
eliminated altogether. This in turn impacts the amount of
electricity or heat that your system produces during those times.
• To overcome this drawback, homeowners can take advantage of
several methods available to them for storing solar energy. The
methods available differ depending on whether you are using
solar electricity applications or solar heating application.
8. SOLAR ELECTRICITY STORAGE
Homeowners are able to generate solar electricity by using a
photovoltaic solar power system. There are two primary methods
of Energy Storage with a PV solar power system...
Battery Banks
Grid Inter-Tie
One way solar power storage can be accomplished is by using a
battery bank to store the electricity generated by the PV solar
power system. A battery solar power storage system is used in a
grid-tied PV system with battery backup and stand-alone PV
systems
9. THE MAJOR COMPONENTS OF A BATTERY
SOLAR POWER SYSTEM ARE-
• Charge Controller: Prevents the battery bank from overcharging by interrupting the flow of electricity from the PV
panels when the battery bank is full.
• Battery Bank: A group of batteries wired together. The batteries are similar to car batteries, but designed specifically to
endure the type of charging and discharging they'll need to handle in a solar power system.
• System Meter: Measures and displays your solar PV systems performance and status.
• Main DC Disconnect: A DC rated breaker between the batteries and the inverter. Allows the inverter to be quickly
disconnected from the battery bank for service.
• The third type of PV solar power system is a grid-tied PV system. This system can actually use the grid as its solar
energy storage system. This is done using net-metering.
• With net-metering, when you produce excess solar electricity, you send it to the grid and your electric meter rolls
backwards. Later on, at night for example, when your system is not producing electricity, you can pull electricity from
the grid and your electric meter will roll forward. You are essentially using the grid to store your solar electricity!
10. THE MAJOR COMPONENTS OF A BATTERY
SOLAR POWER SYSTEM ARE-
• The third type of PV solar power system is a grid-tied PV
system. This system can actually use the grid as its solar
energy storage system. This is done using net-metering.
• With net-metering, when you produce excess solar
electricity, you send it to the grid and your electric meter
rolls backwards. Later on, at night for example, when your
system is not producing electricity, you can pull electricity
from the grid and your electric meter will roll forward. You
are essentially using the grid to store your solar electricity!
11. STORING PHOTOVOLTAIC
ENERGY
Solar panels can not produce energy at night or during
cloudy periods. But rechargeable batteries can store
electricity: the photovoltaic panels charge the battery during
the day, and this power can be drawn upon in the evening.
Residential systems usually use deep-cycle batteries that last
for about ten years and can repeatedly charge and discharge
about 80 percent of their capacity.
While batteries can be expensive, in remote areas it can often
be more cost effective to use batteries rather than extending
an electricity cable to the grid.
But if choosing to go off the grid in this way, the batteries must be sized
correctly, with a storage capacity sufficient to meet electricity needs.
In most cases, though, purchasing electricity from the grid is cheaper
than opting for batteries.
12. SOLAR THERMAL ENERGY
STORAGE
Residential solar hot water systems – which use the sun’s
thermal energy to heat water for the home – have a simpler
storage system. Water flows through solar collectors on the
roof, and then goes to a storage tank where it can be drawn
upon as needed.
• Concentrating solar power(CSP) plants use thermal energy to
power a generator. While some CSP facilities use water as the
heat transfer medium, most new systems us oil or molten salt.
These fluids allow the heat energy to be stored for use during
cloudy periods or at night.
Parabolic troughs at the Plataforma Solar de Almeria CSP facility
in Spain. Photo Credit: PSA.es
The solar resource is enormous. Just 18 days of
sunshine on Earth contains the same amount of
energy as is stored in all of the planet's reserves
of coal, oil, and natural gas.
13. SOLAR POWER PLANT
• Solar power plant is based on the conversion of sunlight
into electricity, either directly using photovoltaics (PV),
or indirectly using concentrated solar power (CSP).
Concentrated solar power systems use lenses or mirrors
and tracking systems to focus a large area of sunlight
into a small beam. Photovoltaics converts light into
electric current using the photoelectric effect.[1] The
largest photovoltaic power plant in the world is the 250
MW Agua Caliente Solar Project in Arizona.[2]
Concentrated solar power plants first appeared in the 1980s.
Now, the 354 MW Solar Energy Generating Systems (SEGS)
CSP installation is the largest solar power plant in the world; it
is located in the Mojave Desert, California. Other large CSP
plants include the Solnova Solar Power Station (150 MW, 250
MW when finished)[3] and the Andasol solar power station (150
MW), both in Spain.[4]Solar power is increasingly used.[5][6] @Murich
Airport.
14. NUCLEAR POWER PLANT
A nuclear power plant is a type of power station that generates
electricity using heat from nuclear reactions. These reactions take place
within a reactor. The plant also has machines which remove heat from
the reactor to operate a steam turbine and generator to make electricity.
Electricity made by nuclear power plants is called nuclear power.
Nuclear power plants are usually near water to remove the heat the
reactor makes. Some nuclear power plants use cooling towers to do this.
Nuclear power plants use uranium as fuel. When the reactor is on,
uranium atoms inside the reactor split into two smaller atoms. When
uranium atoms split, they give off a large amount of heat. This splitting
of atoms is called fission.
The most popular atoms to fission are uranium and plutonium. Those
atoms are slightly radioactive. The atoms produced when fuel atoms
break apart are strongly radioactive. Today, fission only happens in
nuclear reactors. In nuclear reactors, fission only happens when the
reactors parts are arranged properly. Nuclear power plants turn their
reactors off when replacing old nuclear fuel with new fuel.
There are about four hundred nuclear power plants in the world, with many
in the United States, France, and Japan.
16. SOLAR-TO-CHEMICAL ENERGY CONVERSION
WITH PHOTOELECTROCHEMICAL TANDEM
CELLS.
Efficiently and inexpensively converting solar energy into chemical fuels is an important goal towards a sustainable
energy economy. An integrated tandem cell approach could reasonably convert over 20% of the sun's energy directly
into chemical fuels like H2 via water splitting. Many different systems have been investigated using various
combinations of photovoltaic cells and photoelectrodes, but in order to be economically competitive with the
production of H2 from fossil fuels, a practical water splitting tandem cell must optimize cost, longevity and
performance. In this short review, the practical aspects of solar fuel production are considered from the perspective of
a semiconductor-based tandem cell and the latest advances with a very promising technology - metal oxide
photoelectrochemical tandem cells - are presented
Solar energy is an inexhaustible source of energy with the most potential as it will continue to produce solar power as
long as the sun is there. Solar energy is totally free, widely available, produces no pollution, no emission and no noise
which means generating solar power produces no carbon footprint. Among all the renewable energy sources available
on Earth, solar energy is one of the most widely used renewable source of energy.
Solar energy has wide array of uses. It can be used to produce electricity, to run calculators, swimming pool heating,
solar oven or solar cooker. Solar energy can now also be used to fly planes. This technology is however in its initial
stage. In the year 2015, Solar Impulse , the first solar powered aircraft, started its Round-The-World flight from Abu
Dhabi, on March 9. There is no doubt that solar energy is going to play a significant role in meeting demand supply
gap for electricity.
18. LAND USE
Depending on their location, larger utility-scale solar facilities
can raise concerns about land degradation and habitat loss.
Total land area requirements varies depending on the
technology, the topography of the site, and the intensity of the
solar resource. Estimates for utility-scale PV systems range
from 3.5 to 10 acres per megawatt, while estimates for CSP
facilities are between 4 and 16.5 acres per megawatt.
Unlike wind facilities, there is less opportunity for solar
projects to share land with agricultural uses. However, land
impacts from utility-scale solar systems can be minimized by
siting them at lower-quality locations such as brownfields,
abandoned mining land, or existing transportation and
transmission corridors [1, 2]. Smaller scale solar PV arrays,
which can be built on homes or commercial buildings, also
have minimal land use impact.
19. WATER USE
Solar PV cells do not use water for generating electricity. However, as in
all manufacturing processes, some water is used to manufacture solar PV
components.
Concentrating solar thermal plants (CSP), like all thermal electric
plants, require water for cooling. Water use depends on the plant design,
plant location, and the type of cooling system.
CSP plants that use wet-recirculating technology with cooling towers
withdraw between 600 and 650 gallons of water per megawatt-hour of
electricity produced. CSP plants with once-through cooling technology
have higher levels of water withdrawal, but lower total water
consumption (because water is not lost as steam). Dry-cooling technology
can reduce water use at CSP plants by approximately 90 percent [3].
However, the tradeoffs to these water savings are higher costs and lower
efficiencies. In addition, dry-cooling technology is significantly less
effective at temperatures above 100 degrees Fahrenheit.
Many of the regions in the United States that have the highest potential
for solar energy also tend to be those with the driest climates, so careful
consideration of these water tradeoffs is essential.
20. LIFE-CYCLE GLOBAL WARMING EMISSIONS
While there are no global warming emissions associated with generating
electricity from solar energy, there are emissions associated with other stages
of the solar life-cycle, including manufacturing, materials transportation,
installation, maintenance, and decommissioning and dismantlement. Most
estimates of life-cycle emissions for photovoltaic systems are between 0.07
and 0.18 pounds of carbon dioxide equivalent per kilowatt-hour.
Most estimates for concentrating solar power range from 0.08 to 0.2 pounds
of carbon dioxide equivalent per kilowatt-hour. In both cases, this is far less
than the lifecycle emission rates for natural gas.
21. TOP 10 LARGEST INSTALLED SOLAR POWER
CAPACITY COUNTRY IN THE WORLD
Rank Country Name Installed (GW)
1 Germany 35.736
2 China 18.528
3 Italy 17.861
4 Japan 13.947
5 USA 12.035
6 Spain 5.375
7 France 4.639
8 Australia 3.524
9 Belgium 3.470
10 United Kingdom 3.316
22. Q: WHICH IS THE LARGEST
SOLAR POWER PRODUCING
COUNTRY IN THE WORLD?
?
??
??
23. Germanyis the
biggest solar power producer
country in the world. It is less
expensive and have no effect on
humans. It is the most used method
in the world now a days. Hydro is
much expensive and nuclear has
very bad effect on human health as
it reveals radiations.
24. TOP 10 LARGEST ELECTRICITY PRODUCER
COUNTRY IN THE WORLD
Rank Country Name Production (GWh)
1 China 5,649,746
2 USA 4,260,463
3 India 1,102,941
4 Japan 1,088,684
5 Russia 1,069,593
6 Germany 633,618
7 Canada 626,074
8 France 568,584
9 Brazil 557,963
26. WHAT IS THE FATE OF SOLAR ENERGY???
• Some solar radiation is, in fact, absorbed as it travels down through the atmosphere. Mostly, this is
radiation at wavelengths in the two 'tails' of the solar spectrum (Figure 5) - the ultraviolet and the near
infrared.
• Like water vapour and CO2, the ozone in the troposphere acts as a greenhouse gas. Unlike those two
gases, however, very little of the Earth's ozone is, in fact, in the lower atmosphere; the bulk of it (some
90%) is in the stratosphere, where it forms the so-called ozone layer. In this more-rarefied region, ozone
plays a different role because it also absorbs the shorter ultraviolet wavelengths in the solar spectrum -
radiation that is lethal to many micro-organisms and can damage important biological molecules, leading
to conditions such as skin cancer in humans. Fortunately for life on Earth, most of this radiation is
absorbed by the ozone layer, preventing it from penetrating deeper into the atmosphere.
• More pertinent here, the absorption of incoming solar energy by stratospheric ozone heats this region of
the atmosphere directly. In effect, the stratosphere is heated from above, whereas the troposphere is
heated from below. This is why the highest temperatures are found at the top of the stratosphere, but at
the bottom of the troposphere.
27. WHAT IS THE FATE OF SOLAR ENERGY???
• About half of the incoming near-infrared radiation is also absorbed, mainly by water vapor low
down in the troposphere. In addition, the atmosphere contains a huge assortment of aerosols - fine
solid particles and liquid droplets suspended in the air.
• Except in the aftermath of a major volcanic eruption (of which more in Section 1.5), aerosols are
also most abundant in the lower atmosphere; natural sources include desert dust wafted into the
air by wind, smoke and soot from wildfires, salt from sea-spray, and so on.
• Depending on their make-up, aerosols can absorb solar radiation - or (and this is usually more
important) scatter some of it back to space. Globally, aerosols make a significant contribution to the
Earth's albedo (included in the figure of 31% quoted earlier). They also play another important
role.
• Many aerosols act as cloud condensation nuclei, providing surfaces that promote the condensation
of water vapor to form the liquid droplets (or ice crystals, at higher and colder altitudes) suspended
in clouds - a process that occurs less readily in 'clean' (i.e. aerosol-free) air.