Due
to the negative impacts of coal and oil on the environment as well as
shortages of supply, research has been going on for the last few
decades trying to find a greener alternative. While there are many
possible alternatives for energy, one of the most known and biggest
competitors is solar energy, harnessing the sun’s energy to power
homes and businesses. While research has been going on for the last
few decades, there has been much debate on whether using solar panels
to power your home or business is really worth it, and is it really
more efficient than coal and oil. Solar energy is certainly more
renewable and much greener than coal and oil, but how efficient is it
compared to coal and oil? Especially for those that live in cold
climates or heavily wooded areas. The way a solar panel works can
give both advantages and disadvantages to a home, depending on both
location and energy consumption. Although there are many pros to
using solar energy, there are also many drawbacks which are
preventing it from replacing coal and oil entirely. This essay will
examine how a solar system works to power a home, and then look at
the pros and cons of using solar energy to see how it stacks up
against coal and oil as an energy source.
Solar
panels for one create energy using the sun’s light, not the heat.
So although it is partly true that solar panels are less effective in
colder areas where the sun is not as present, there are still areas
with typically colder climates that can still take advantage of solar
energy. Solar panels are made of many photovoltaic cells. The way a
photovoltaic cell works is divided into a few basic steps. When the
sun’s light hits a cell it gets absorbed into a semiconductor.
Silicon is the most common material used for semiconductors due to
its crystalline structure (Toothman and Aldous 3). Silicon is a shiny
material and usually reflects a lot of the light, which is why solar
panels are coated in a special finish to fix this problem. When the
light gets absorbed into the semiconductor, the energy knocks
electrons loose in the silicon layer which causes the electrons to
flow freely which creates a current. The cell has an electric field
which, according to Toothman and Aldous, acts as a diode. The
electric field has holes without any electrons that also move freely.
The electric field moves the holes to what is called the “P” side
of the spectrum, and forces the electrons to the “N” side of the
spectrum which creates an imbalance between the two, and then when
the electrons move back towards the holes on the “P” side, they
create a current while the electric field creates voltage and both
together creates power. The energy is then transferred to the
circuitry of a household or building which is then put onto
electrical grid, or if an “off-grid” system is used (the
household runs strictly on the solar panels and has no electrical
power lines from the nearest power plant), the energy is then sent to
batteries for storage of unused energy which then can be used at
night when the sun’s light cannot be harnessed (SolarWorld-usa).
During
the process of absorbing light and converting into electricity, not
all of it is converted. Much of the light energy is lost during the
process. The photovoltaic cell can only absorb certain types of light
within a certain energy range on the electromagnetic spectrum. The
sun’s light has photons with a wide range of energy. When a photon
with too little energy to knock an electron loose, will just travel
right through the solar system like it is not even there (Toothman
and Aldous 5). If a photon has too much energy, the photovoltaic cell
can only absorb a certain amount of energy so the cell will absorb
that required amount of energy and then the rest is lost. According
to Toothman and Aldous, this total energy loss accounts for about 70%
energy loss of all the light that strikes a photovoltaic system (5).
Although this issue causes many to question the efficiency of solar
energy usage, there is also still the question of whether that
inefficiency really matters enough to make solar energy a bad option
on a home or business building.
Advantages
of Solar Energy
Solar
Energy has many advantages over fossil fuels, and most sources will
say that as technology improves and price of solar energy systems
drops, the list of advantages will improve and the disadvantages will
decrease. As Sanford C. Bernstein, owner of Bernstein Research
mentions in his published results of a study on solar energy, “Solar
and the Next Energy Revolution,” solar energy is down near $1/W
from S7.50 in 2007, which makes it a competitor against fossil fuels
on the world energy market (5). While the cost of solar energy is
going down and becoming more efficient with technology, the cost of
fossil fuels is going up since it is not as renewable. Greg Whitburn,
a writer for Exploring Green Technology points out that in the past
decade economic politics have doubled the price of fossil fuels due
to shortages, whereas the price of solar energy has more than halved
(Whitburn). It is predicted that the cost of fossil fuels will
continue to go up in the upcoming years, and as technology improves,
solar energy will continue to decrease in price and may eventually
surpass fossil fuels in price. Bernstein remains optimistic about the
price of solar energy systems and believes that solar energy usage
will greatly increase in increments of 1.5% a year world wide by 2020
(5).
Above
is a chart comparing the cost of solar energy to the average cost of
regular electricity in 2009, and how the cost of solar energy will
change in the future. Bernstein Research puts solar energy at a price
of $1.23/W, natural gas at $1.10/W and coal at $0.44/W as of 2012
(8). Not only is the rapidly falling cost an advantage of solar
energy, but there are many others as well.
Another
great advantage that solar energy has over fossil fuels is that it is
much more renewable. Solar energy will always be given off by the
sun, forever, at least until the sun dies off in billions of years.
Fossil fuels are hardly renewable since oil takes millions of years
to form, and at the rate humans are using it up, it is estimated that
the worlds current oil supply will only last forty more years. Solar
energy will never run out and will be available every day the sun
shines, which makes solar energy very abundant. Solar energy is
certainly much more environmentally friendly than fossil fuels, since
solar energy does not give off any carbon or other pollutants
generated by fossil fuels, which also makes it much more sustainable.
Using solar energy would greatly decrease an individual’s carbon
footprint. Solar panels are also silent, they do not make any noise
when producing electricity or heat for hot water, whereas generators
operated by gas or coal make loud noises. Solar panels require very
little maintenance and with improving technology, solar companies
offer 25-30 year warranties and it is estimated that a solar panel
will last 40 years before having to be replaced (Whitburn). To sum it
all up; solar energy is more renewable, abundant, sustainable,
greener, quieter, and requires less maintenance than fossil fuels.
There
are two types of solar energy supplies. There is On-Grid, which means
that the household with solar panels is still on the state
electricity grid, using power lines from the nearest electric power
plant, and is still using that electricity when the solar panels are
not absorbing light. On-Grid solar systems usually still require the
household to pay electricity bills, but far less per month than a
house without any solar panels at all, and will still have a much
smaller carbon footprint (Whitman). Then there is Off-Grid, which
means a household is off of the state electricity grid and relies
solely on the solar panels for electricity. There is no power lines
connected to the house, and therefore absolutely no electricity
bills. However, rechargeable batteries are needed and must be stored
in the household somewhere, so electricity can be used at night. This
is a great advantage for households that are out in rural areas and
far away from power plants. Households in rural areas can be very
expensive to install power lines, making off-grid energy production
very beneficial and a good investment. Also one will not have to
worry about power outages if they use the off-grid energy system.
Disadvantages
Although
solar energy has many advantages over fossil fuels, there are also
drawbacks, and these drawbacks are preventing many people from
switching to solar systems for their homes and businesses. The
biggest disadvantage of solar energy usage is current costs. Sure,
one can get free electricity from solar panels once installed and can
get free energy for as long as the solar panels last. However, solar
panels are made out of some rare materials and are very expensive to
produce, and must be bought up front. Many people do not like paying
that much money up front. As Whitman puts it in his article; it is
like paying for the next 30 years of energy up front in one day. The
cost of solar energy makes it a competitor against fossil fuels on
the market, but is still more expensive per kilowatt hour (KWh) in
most areas. This varies a little bit since energy prices are not the
same everywhere and solar panels obviously work better in sunnier
climates, but fossil fuels still come out on top for price per KWh by
a small margin, which is predicted to continue get smaller in the
future. Looking at the national sunshine map of the U.S. you can see
that some places (generally south) get more annual sun light then
other places (like Alaska).
This
difference in location will affect how effective solar panels are,
and cause price to vary a little. Like Bernstein mentioned, fossil
fuels will continue to rise in price, while solar energy will
continue to fall. Cost is the biggest and most argued disadvantage
for solar energy, but there are also other disadvantages.
Obviously,
solar panels do not work at night when the sun is not shining. This
requires households to stay connected to the power grid and use
electricity from fossil fuels at night, or they have to get
rechargeable solar batteries to stay off-grid. While the rechargeable
batteries are a good alternative, the technology has not been
perfected yet and the batteries are large, costly, and require much
space to store (Whitman). Although creating energy off-grid can be
very advantageous for houses in isolated rural areas, since it would
be very expensive to run power lines to a household far from a power
plant. Not only do solar panels not work at night, but they cannot
produce as much electricity during winter months, especially in
northern regions where the sun does not shine much, and snow can
greatly impact the effectiveness of the solar panels. So the location
of a household also impacts the effectiveness of solar energy. A
household in Arizona would generate a lot of electricity year around,
whereas a household in Wisconsin would not be able to generate much
in the winter. Also houses with trees or tall buildings surrounding
them may not be able to gain the full potential of their solar panels
if trees or buildings are blocking the sun. Pollution also effects
how well solar panels work, so houses or business buildings in highly
polluted cities may not get the full potential from solar panels. One
of the last disadvantages of solar panels is that they require a lot
of space and many people do not like the aesthetics of solar panels
on their roof or their lawn. Solar panels only have an efficiency
rate of 20%-40%, so solar panels require a large surface area to
produce a sufficient supply of electricity. This also requires people
to buy more than one solar panel unit to power their home. Some solar
panels have better efficiency than others, but are also more
expensive, keeping the cost issue a disadvantage. However, as
technology improves, solar panels are becoming more and more
efficient.
So,
are solar panels worth investing in and is solar energy going to
become a main energy source in the future? As for whether solar
panels will save you money, that is for you to decide, since
electricity prices vary from place to place and prices are always
changing. In my opinion, solar energy may be something to look into
since fossil fuels continue to rise in price, especially oil. I agree
with Bernstein that soon solar energy will surpass fossil fuels in
terms of cost per KWh and at that point will definitely be a yes.
Although solar energy is currently more expensive than fossil fuels,
let’s not forget that a solar system lasts for about 40 years, and
it is estimated that the world’s oil supply will be gone around
that time. Also, solar energy does not give off any pollution and is
completely quiet. Sure it may cost a bit more (for now), but I feel
like I would not mind paying the little bit of extra money to almost
completely eliminate my carbon footprint. I think I may look into
solar energy in a few years when I am out of college and looking for
a house, and hopefully that price gap between solar energy and fossil
fuels will be even smaller, or non-existent. It is an individual’s
own opinion on whether solar panels are currently worth investing in
based on where they live, but in my opinion will be worth investing
in, in a couple of years.
In
conclusion solar energy has been one of the most sought after energy
alternatives to fossil fuels and is currently one of the biggest
competitors. Solar panels are a fairly new technology and are
constantly being improved to harness more energy through photovoltaic
cells. Solar energy has many advantages over fossil fuels currently.
Solar energy has a rapidly falling price per KWh while fossil fuels
are increasing, which makes solar energy a competitor in price
currently, and soon will be cheaper than fossil fuels. On top of that
solar energy is renewable, abundant, sustainable, environmentally
friendly, quiet, requires low maintenance, is constantly improving in
technology and efficiency, and an off-grid system can be very good
for houses in rural areas. With many advantages, solar energy also
has some disadvantages. These disadvantages include: current cost,
solar panels require certain climates and locations, solar panels do
not work at night, and they are inefficient at harnessing the sun’s
light which causes them to require a lot of surface area. However, it
is predicted that the list of disadvantages will get much smaller in
the years to come, especially cost. Is solar energy going to become a
widely used energy source and possibly replace much of the fossil
fuel usage? Only time will tell if solar energy becomes a widely used
energy source worldwide, but the statistics are looking good.
Works
Cited
Aldous,
Scott; Toothman, Jessika. “How Solar Cells Work.”
Science.howstuffworks.com.
01
April 2000. Web. 12 March 2014.
Bernstein,
Sanford C. Solar
and the Next Energy Revolution: Beginning to see light. New
York:
Bernstein
Research, 2013. Print.
Whitburn,
Greg. “Advantages and Disadvantages of Solar Energy”
www.exploringgreentechnology.com.
Web.
12 March 2014.
Web.
12 March 2014.
No comments:
Post a Comment