2. Contents
Introduction
Maungaraki solar power
Solar – all the basics
Photovoltaic cells
Solar panels and they work
Model of a solar panel
Electrons
How could solar energy benefit us?
How much can we save from solar power?
Does your location affect the amount of solar energy you produce?
Solar inverters
How much sun does wellington get?
Letter to Peter Dunne
Conclusion
Glossary
Websites used
3. Introduction
Solar energy is a source we have only recently tapped into. However, it may become the most important
energy source in the future because it is cheap, renewable and clean
This project looks at solar power and how it is used. In particular it focusses on:
Maungaraki solar power
Solar energy and all the basics
Photovoltaic cells
Solar energy and how it works
Electrons
How solar energy could benefit us
How much money we could save with solar
What solar cookers are
If your location affects the amount of solar you could produce
An inverter and what that is
And how much sun wellington actually gets
4. Maungaraki solar power
The solar panel glass on the roof of Maungaraki School is 3.3 mm thick
In its lifetime these solar panels have generated 5755kWh.
On 18 May it was raining, and the amount of power we generated was, 14,75 kWh
On 19 May it was sunny and we generated 39.22 kWh
Exported from Maungaraki School roof to the grid on 19 May was 8hrs and 31mins worth of power
Exported on 18 May was 7hrs 41mins worth of power
The overall amount that the solar panels have exported to the grid is 6 days and 23 hours worth
This amount of energy is enough to power:
1. to drive a typical car 7 thousand metres
2. to power 28 houses of three people for a week
4. to cook 306,000 pieces of toast
3. to boil 242,000 cups of tea
5. Solar – all the basics
We can use solar power for many things such as:
• Cooking
• Water heating
• Building heating
• Power generation
There are three main ways to convert energy from sun:
• Photovoltaic cells (also known as solar panels)
• Boiling a fluid using the intense heat of the sun and using it to spin a turbine
• Solar converters
Solar power is different to conventional power because:
• It is eco-friendly
• It doesn’t produce huge amounts of pollutants
• It can be generated within your own home (although there are some large solar power plants in existence)
• After it has been installed it doesn’t need any additional money to go into it.
Lots of systems can be set to “trace the sun”, by doing this you are maximising the amount or efficiency
you can gain from the sun
6. Photovoltaic cells
“Photovoltaic” is another word for solar
Photovoltaics is best known as a way for generating electric power by using solar cells to convert
energy from the sun into a flow of electrons. Photovoltaic cells work with what is known as a
photovoltaic effect
The photovoltaic effect refers to photons of light exciting electrons into a higher state of energy,
allowing them to act as charge carriers for an electric current
Photovoltaic cells are made up of lots of “semiconductors”
Solar photovoltaics power generation has long been seen as a clean sustainable energy technology
which draws upon the planet’s most plentiful and widely distributed renewable energy source –
the sun. The direct conversion of sunlight to electricity occurs without any moving parts or
environmental emissions during operation. It is well proven, as photovoltaic systems have now
been used for fifty years in specialized applications, and grid-connected systems have been in use
for over twenty years.
7. Solar panels and how they work
Solar panels are designed to convert the sunlight's photovoltaic rays into energy
A solar panel is a set of photovoltaic modules connected and then mounted on a structure
A photovoltaic module is a connected Pack of solar cells
Each module typically has a current of between 100 and 320 volts
Solar panels are made up of many small solar cells. Each solar cell uses light to make electricity
The electrons in the solar cells move when under photovoltaic rays from the sun
When the rays of light hit an electron in the first layer, the electrons jump from the first to the
second. That electron makes another electron move, then another, starting a chain reaction
The solar cell is 2 different layers stuck together. The first layer is stuffed with electrons so these
electrons are ready to jump from the first layer to the second. Once the electrons have jumped
from the first layer to the second, the second layer has some electrons taken away so there is room
for more electrons to enter
The moving of electrons from the first to the second creates a friction, causing energy to be made
9. Electrons
An electron is part of a solar panel
An electron is a stable subatomic particle with a charge of negative electricity, found in all atoms
and acting as the primary carrier of electricity in solids
Electrons are the subatomic particles that orbit the nucleus of an atom.
Even if we had a microscope, we could still not see electrons (they are much to small) as they move
too fast
Electrons are considered to be part of the first generation of the lepton family
Electrons are thought to be elementary particles because they have no known components or
structure
Electrons are very small compared to all of the other pieces of the atom. The size of an electron is
almost 1000 times smaller than the size of a proton (1/1836th )
10. How could solar energy benefit us?
Solar power is a renewable source, so it wont run out
An obvious advantage to using solar power is that it will definitely slow down global warming
Also, solar power does not pollute the air around it, so it will not emit large amounts of greenhouse gases
Once you have purchased the equipment for the solar panels, there is no further cost
Solar power requires little maintenance
Solar cells can last a lifetime
Solar power is silent
Society could save billions and trillions of dollars by using solar power
Solar energy is reliable as the sun will always come up the next morning and charge the solar panels
The installation of solar panels creates lots of jobs
It is more resourceful than some of the other power sources because it is there when we need it (we are
more active in the middle of the day which is when we get more sun)
And most importantly, it will help to put planet earth on a track for a better future
11. How much money can we save from solar
power?
Each household could save $20,000 in twenty years
People who decide to use solar energy are advised to do some thorough research before
committing, but for most, it will be beneficial
New Zealanders get around 2,000 hours of sunshine a year, meaning we get sunshine around 25%
of the year
Every month 50-60 solar power systems appear on roofs nation-wide, in the process creating a
$44.5 million dollar a year industry
The cost of installing solar panels has gone down over 80% since 2008
Solar power is overall cheaper than utility power
12. Solar cookers
There are lots of different things that use solar power. One of these is solar cookers. The three main designs of solar
cookers are
• Box
• Panel
• Parabolic
The box cookers are a simple box that has a transparent lid so that the rays from the sun may enter. Some box
cookers also have reflectors to maximise the amount of light and heat entering the box. The light entering the box
heats it to a high temperature therefore heating the food
Panel cookers work the way they sound, by focusing strong beam of light into one spot using lots of flat panels. The
idea is to place a pot or other cooking dish on the spot the light is focused, the heat from the light heats the dish
therefore cooking the food inside
The parabolic cookers are convex shaped dishes. These are used to focus the energy onto the base of the pot pan.
This method of solar cooker cooks as fast as your oven at home would. The disadvantages of using this method of
cooking are
• Cost
• They are hard to make
• They require frequent refocussing
13. Does your location affect the amount of solar
energy you produce?
The amount of energy that you can draw from the sun depends on how much sun your location
actually gets
If your location is a place with lots of sun, or in a wide-open place with no hills or trees to block the
sun, then solar panels are probably a very good thing for you and your house
If you are backed into a cliff, or live in a mountain area, then the amount of electricity you would
produce from solar panels could be affected, and you would most likely end up not getting a good
outcome
14. Solar inverters
Solar inverters convert the changing amount of energy coming from the panels into one constant
stream. This is to prevent too much strain on the appliances. There are three main sorts:
Stand alone inverters
Used in isolated systems where the inverter draws its energy from batteries
Normally these do not interact in any way with the power grid
Grid tie inverters
Grid-tie inverters are designed to shut down automatically when power supply cuts out, for safety
reasons
They do not provide backup power during power outs
Battery backup inverters
These are special inverters which are designed to extract energy from a battery, manage the battery
charge through an on board charger, and export left over energy to the power grid
These inverters are capable of supplying energy of selected loads during a power out
15. How much sun does Wellington get?
0
1
2
3
4
5
6
7
Average sun hours
2011
wellington
Jan=6.46 Feb=5.52 Mar3.03 Apr=4.11 May=2.99 Jun=2.33 jul=2.27 Aug=3.46 Sep=4.56 Oct=4.84 Nov=5.67 Dec=5.67
16. Action letter to Peter Dunne Member of
Parliament Ohariu
184 Dowse Drive
Maungaraki
Lower Hutt
New Zealand
Dear Mr Dunne,
I think that solar energy should be the main power source for schools in New Zealand. This is because it is cheaper and renewable. For
example my school Maungaraki makes so much solar electricity that it gives power back to the grid.
Solar power is more resourceful than others because the sun will never run out and the solar ultraviolet rays never go away even if it is
cloudy.
Solar power is convenient because once you have bought the solar panels, solar energy is free.
There are many advantages and benefits with solar energy, such as the fact that it is renewable, it requires little maintenance, its silent,
and It is renewable!!
Thank you for reading this letter and I would love you to consider the possibility of solar panels throughout New Zealand schools.
Yours faithfully,
Alyssa Briscoe.
17. Conclusion
Solar power is a big part of our lives and will become a huge part of our future
Our school is helping out too because we installed solar panels on our roofs. We are
generating so much power we are sending power back into the grid
We can use solar power for many things such as cooking. We harness solar energy by
using photovoltaic cells to convert sun into energy
Solar panels are connected packs of photovoltaic (solar) cells
An electron is an important part of a solar panel
Solar energy is beneficial in many ways. It is reliable, resourceful, silent, renewable, and
clean
We can save lots of money and lower our power bills with solar power
We can cook with solar cookers
Your location will effect the benefits of solar panels. If your house gets lots of sun you will
be able to produce more power and save more money
18. Glossary
Renewable = A natural resource or source of energy that is not depleted by use, such as water, wind, or solar
power. "production costs for the renewables are higher than for coal, oil, or gas“
Photovoltaic cells = A small conductive device that can produce an electric current when light shines on the cell.
Learn more about photovoltaic cell in the class Photonic Semiconductor Devices 355 below.
Efficiency = The state or quality of being efficient ."greater energy efficiency "synonyms: organization, order,
orderliness, planning, regulation, logicality, coherence, productivity, effectiveness, cost-effectiveness
Electrons = A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the
primary carrier of electricity in solids
Electric current = An electric current is a flow of electric charge. In electric circuits this charge is often carried by
moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as
in a plasma
Photovoltaic modules = Spacecraft operating in the inner solar system usually rely on the use of photovoltaic
solar panels to derive electricity from sunlight. Photovoltaic solar cells on spacecraft was one of the earliest
applications of photovoltaic cells
19. Glossary continued
Subatomic = smaller than or occurring within an atom
Orbit = the regularly repeated elliptical course of a celestial object or spacecraft about a star or planet. "the
Earth's orbit around the sun“ synonyms : course, path, circuit, track, trajectory, rotation, revolution, circle, cycle,
round
Nucleus = the positively charged central core of an atom, consisting of protons and neutrons and containing
nearly all its mass
Atom = The smallest part of a chemical that can exist. Synonyms: particle, molecule, bit, little bit, tiny bit, tiny
piece, fragment, fraction, grain, granule, crumb, morsel, mite, mote, speck, spot, dot
Protons = a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in
magnitude to that of an electron.
Convex = having an outline or surface curved like the exterior of a circle or sphere. “A convex lens“ synonyms:
curved outwards, cambered
