Difference between revisions of "AY Honors/Renewable Energy/Answer Key"

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'''Renewable energy''' is any type of energy which has an abundant
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and ongoing source, such as the [[sun]]'s rays, wind, waves, rivers,
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tides and the heat from radioactive decay in the earth's core as well
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as biomass. Renewable energy does not include energy sources which
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are dependent upon a limited resource, such as [[fossil fuels]] and  
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[[nuclear power|nuclear fission power]].  
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 +
<!-- 1. What is renewable energy? -->
 +
Renewable energy is energy whose origins are continually and naturally replenished without human intervention. Examples of renewable energy sources include sunlight, wind, and waves.
  
Renewable energy may be used directly (as in [[solar oven]]s,
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geothermal [[heat pump]]s, and [[windmill]]s) or be used to
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[[electricity generation|generate electricity]] or create fuels such
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as [[ethanol]]. Only the power of falling water in rivers
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([[hydroelectricity]]), has been significantly tapped for the  
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generation of electricity so far. [[solar power | Solar energy]]'s  
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main human application has been in agriculture and forestry, via
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<!-- 2. Why is renewable energy important? -->
photosynthesis, and increasingly it is harnessed for heat.  
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As the demand for energy resources continues to climb, mankind is faced with the dilemma of depleting the earth's resources to meet the demand. With the discovery of processes designed to harness clean and renewable energy, depletion of such resources will not be an issue, since they are naturally replenished. In addition, these processes have much less of an environmental impact than conventional methods used to harness resources such as oil.
[[Biomass]] (eg sugar cane residue) is burned where it can be
 
utilised. The others are little used today.  
 
  
Most renewable energy can trace their root to solar energy, perhaps
 
with the exception of geothermal and tidal wave power.  For example,
 
wind is caused by the sun heating the earth unevenly. Hot air is less
 
dense, so it expands, moving to a less dense area.  Hydroelectric
 
power can be ultimately traced to the sun too.  When the sun
 
evaporates water in the ocean, the vapor forms clouds which later
 
fall on mountains as rain which runs through turbines to generate
 
electrity.  The transformation goes from solar energy to potential
 
energy to kinetic energy to electric energy.
 
  
Turning to the use of renewable energy sources for electricity, there
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are immediate challenges in actually harnessing them. Apart from
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[[photovoltaic]] (PV) systems, which turn sunlight directly into
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electricity, the question is how to make them turn dynamos to
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generate the electricity. If heat is harnessed, a steam generating
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system powers a turbine.  
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<!-- 3. Describe how each of the following sources is used as a renewable source of energy. Draw an illustration depicting the usage of at least 3 of these renewable sources of energy. -->
  
If the fundamental opportunity of renewables is their abundance and
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relatively widespread occurrence, the fundamental problem, especially
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for electricity supply, is their variable and diffuse nature (The
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exception being geothermal energy, which is however only accessible
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where the earth's crust is thin, such as near hotsprings and natural  
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geisers). This means either that there must be reliable overlapping
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Wind Power is energy that has been converted from the natural movement of wind by the use of devices such as wind turbines. It is clean, largely available, and produces no greenhouse gas emissions.
sources of electricity, or some means of electricity storage on a
 
large scale. Apart from pumped-storage hydro systems, no such means
 
exist at present, though use of hydrogen [[fuelcell]]s is a distinct
 
possibility. For a stand-alone system the energy storage problem
 
remains paramount. If linking to a grid, the question of duplicate
 
sources arises. For large-scale and especially base-load electricity
 
generation there is little scope for harnessing the sun.  
 
  
Renewable energy sources have a completely different set of
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environmental costs and benefits than fossil fuel or nuclear power
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plants. On the positive side they emit no [[carbon dioxide]] or other
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air pollutants (beyond some decay products from new hydroelectric
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reservoirs), but because they are harnessing relatively low-intensity
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energy, their 'footprint' - the area taken up by them - is  
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necessarily much larger. Whether large areas near cities dedicated to
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Bioenergy is biomass energy, which is energy from organic matter. Wood, plants, even the fumes from landfills can be used as a biomass energy source.
solar collectors will be acceptable, if such proposals are ever made,  
+
Ethanol is a fuel made from corn, sugar cane and other sources used in auto and jet fuel.
remains to be seen. Beyond utilising roofs, 1000 [[MWe]] of solar
 
capacity would require at least 20 square kilometres of collectors,
 
shading a lot of country. In Europe, wind turbines have not endeared
 
themselves to neighbours on aesthetic, noise or nature conservation
 
grounds, and this has slowed their deployment. However, European
 
non-fossil fuel obligations have led to increases in offshore wind
 
development. However, much of the environmental impact can be
 
reduced. Fixed solar collectors can double as noise barriers along
 
highways, roof-tops are available already, and there are places where
 
(redesigned) wind turbines would not obtrude unduly.  
 
  
----
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Geothermal energy is energy that is created and stored in the earth. It can be used for heating for large areas, mineral recovery, and industrial process heating.
  
<h3>Types of renewable energy</h3>
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There are several types of renewable energy, most are mentioned
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below:  
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* Solar energy
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* Wind energy
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* Geothermal energy
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* Hydroelectric energy
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Hydropower is energy that is comes from falling water. Most commonly electricity from dams or run of the river generation turbines is created. Other uses are irrigation and (in pioneer times) falling water was directly harnessed with water wheels for the operation of gristmills and sawmills.
* Biomatter & Biogas Energy
 
* [[Nuclear fusion]] (though it's place on this list is debatable)
 
  
Ofcourse there are some small scale applications aswell.
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* [[piezoelectricity|Piezo electric]] crystals embedded in the sole of a shoe can yield a small amount of energy with each step.
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* A [[speedbump]] can convert the force of an impact into electricity.
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* Vibration from [[internal combustion engine|engines]] can stimulate piezo electric crystals.
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* Some watches are already powered by movement of the arm.
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* Special [[antenna]]e can collect energy from stray radiowaves or even light ([[Electromagnetic radiation|EM radiation]].
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 +
Ocean Energy is energy that is comes from the ocean, which can be responsible for two types of energy: mechanical energy from the tides and waves, and thermal energy from the heat of the sun. It can be used for generating electricity.
  
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Solar Power is light and heat that is derived from the sun and collected through solar panels. It can be used to generate electricity for a variety of useful applications.
  
==SOLAR ENERGY==
 
  
"Solar not nuclear" is a catch-cry of both antinuclear environmental
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groups and many technological optimists, particularly as advances in
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direct solar heating continue to be made. Certainly we can expect to
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see more roof area occupied by some kind of solar collectors in the  
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future (especially for waterheating), as their price comes down and
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we adapt our energy usage to utilise better what is available from
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this source.  
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 +
<!-- 4. Individually or as a group, discuss some of the earliest forms of renewable energy. Are there energy forms that might have been used before sin? By Noah? By the patriarchs? -->
  
===Electical energy===
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 +
The earliest form of renewable energy was probably the burning of biomass in the form of wood and dried animal dung. The fuel could be stored, and energy was available for immediate use, but the energy could not be kept in storage for afterwards.
  
However, for electricity generation ground based solar power has limited
+
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potential, as it is too diffuse and too intermittent. First, ground based solar input is interrupted by night and by cloud cover, which means that solar electric generation inevitably has a low capacity factor, typically less than 15%. Also, there is a low intensity of incoming radiation, and converting this to high grade electricity is still relatively inefficient (12 - 16 percent), though increased efficiency or lower production costs have been the subject of much research over several decades.  
+
Some people believe that the pre-flood culture had advanced technologies. Out of place artifacts like machined balls and gold chains inside coal suggest this. Consider how much knowledge a person living hundreds of years and so close to God's perfect creation of Adam and Eve could amass and what they could create with that knowledge. The world had one language as well, and many overlapping generations, facilitating communication.
  
Two methods of converting the sun's radiant energy to electricity are the focus of attention. The better known method utilises sunlight acting on [[photovoltaic]] (PV) cells to produce electricity. This has application on satellites and for certain earthbound signalling and communication equipment, such as remote area telecommunications equipment. Sales of solar PV modules are increasing strongly as their efficiency increases and price diminishes. But the high cost per unit of electricity still rules out ordinary use.  
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 +
Additional references are available from the Bible which can provide further insight into this. For example, the sun, the movement of water through rivers, etc.
  
Several experimental PV power plants mostly of 300 - 500 kW capacity are connected to electricity grids in Europe and the USA. Japan has 150 MWe installed. A large solar PV plant was planned for Crete. Research continues into ways to make the actual solar collecting cells less expensive and more efficient. Other major research is investigating economic ways to store the energy which is collected from the sun's rays during the day.  
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<!-- 5. Individually or as a group, show at least five important events in the history of renewable energy through:<br>a. Presentation<br>b. Video<br>c. Interactive game<br>d. Speech<br>e. Display -->
 +
For this requirement, you will need to research the history of renewable energy, and then present your findings using one of the techniques listed in the requirement.
  
A typical solar thermal power plant has a system of mirrors to concentrate the sunlight on to an absorber, the resulting heat then being used to drive turbines. The concentrator is usually a long parabolic mirror trough oriented north-south, which tilts, tracking the sun's path through the day. A black absorber tube is located at the focal point and converts the solar radiation to heat (about 400 degrees [[Celsius]]) which is transferred into a fluid such as synthetic oil. The oil can be used to heat buildings or water, or it can be used to drive a conventional turbine and generator. Several such installations in modules of 80 MW are now operating. Each module requires about 50 hectares of land and needs very precise engineering and control. These plants are supplemented by a gas-fired boiler which ensures full-time energy output. The gas generates about a quarter of the overall power output and keeps the system warm
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overnight. Over 350 MWe capacity worldwide has supplied about 80% of the total solar electricity to the mid 1990s.  
+
Prior to the development of coal in the mid 19th century, nearly all energy used was renewable. Almost without a doubt the oldest known use of renewable energy, in the form of traditional biomass to fuel fires, dates from the beginning of history.
  
Alternatively, many individuals have installed small-scale PV arrays for domestic consumption.  Some, particularly in isolated areas, are totally disconnected from the main power grid, and rely on a surplus of generation capacity combined with batteries and/or a fossil fuel generator to cover periods when the cells are not operating.  Others in more settled areas remain connected to the grid, using the grid to obtain electricity when solar cells are not providing power, and selling their surplus back to the grid.  This works reasonably well in many climates, as the peak time for energy consumption is on hot, sunny days where air conditioners are running and solar cells produce their maximum power output.  It is still considerably more expensive for the consumer than grid electricity.  
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 +
Probably the second oldest usage of renewable energy is harnessing the wind in order to drive ships over water. This practice can be traced back to ships on the Nile.
  
A simple proposal for a solar electrical plant is the [[solar tower]], in which a large area of land would be covered by a greenhouse made of something as simple as transparent foil, with a tall lightweight tower in the centre, which could also be composed largely of foil.  The heated air would rush to and up the centre tower, spinning a turbine. A system of water pipes placed throughout the greenhouse would allow the capture of excess thermal energy, to be released throughout the night and thus providing 24-hour power production.  A 200 MWe tower is proposed near [[Mildura, Australia]].
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 +
The primary sources of traditional renewable energy were human labor, animal power, water power, wind, in grain crushing windmills, and firewood, a traditional biomass. A graph of energy use in the United States up until 1900 shows oil and natural gas with about the same importance in 1900 as wind and solar played in 2010.
  
===Thermal energy===
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 +
By 1873, concerns of running out of coal prompted experiments with using solar energy. Development of solar engines continued until the outbreak of World War I. The importance of solar energy was recognized in a 1911 Scientific American article: "in the far distant future, natural fuels having been exhausted [solar power] will remain as the only means of existence of the human race".
  
The main role of solar energy in the future may be that of direct
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heating. Much of our energy need is for heat below 60 degrees C
+
The theory of peak oil was published in 1956. In the 1970s environmentalists promoted the development of renewable energy both as a replacement for the eventual depletion of oil, as well as for an escape from dependence on oil, and the first electricity generating wind turbines appeared. Solar had long been used for heating and cooling, but solar panels were too costly to build solar farms until 1980.
(140F) - eg. in hot water systems. A lot more, particularly in
 
industry, is for heat in the range 60 - 110 degrees C. Together these
 
may account for a significant proportion of primary energy use in
 
industrialised nations. The first need can readily be supplied by
 
solar power much of the time in some places, and the second
 
application commercially is probably not far off. Such uses will
 
diminish to some extent both the demand for electricity and the
 
consumption of fossil fuels, particularly if coupled with [[energy
 
conservation]] measures such as insulation.  
 
  
Domestic solar hot water systems are common in the hotter areas of
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Australia, and simply consist of a network of dark-coloured pipes
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running beneath a window of heat-trapping glass. They typically have
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a backup electric or gas heating unit for cloudy days. Such systems
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can actually be justified purely on economic grounds, particularly in
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some remoter areas of Australia where electricity is expensive.
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<!-- 6. Discover the source of most reusable energy. -->
 +
The source of most renewable energy comes from the sun.
  
With adequate insulation, [[heat pump]]s utilising the conventional
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refrigeration cycle can be used to warm and cool buildings, with very
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little energy input other than energy needed to run a compressor.  
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Eventually, up to ten percent of the total primary energy need in
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industrialised countries may be supplied by direct solar thermal
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techniques, and to some extent this will substitute for base-load
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electrical energy.  
+
<!-- 7. What are some commercial and industrial uses of renewable energy? -->
 +
Renewable energy such as solar energy can be used to supply power larger communities through a solar power station. Tanks of molten salt can be used to store the energy harnessed from the sun for the purpose of generating electricity during cloud cover, or through the night. Renewable energy can also be used for agricultural purposes, providing social services, education, and health care.
  
Large scale solar thermal powerplants, as mentioned before, can be
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used to heat buildings, but on a smaller scale [[solar oven]]s can be
+
Fuel made from bio sources like corn is now a common ingredient in automotive fuel.  
used on sunny days. Such an oven or solar furnace uses mirrors or a
 
large lens to foccuss the [[sun]]'s rays onto a baking tray or black
 
pot which heats up as it would in a standard [[oven]].
 
  
 +
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 +
Hydro electric power (electricity) is a renewable energy used everywhere the grid goes.
  
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<!-- 8. Why have many governments invested in renewable energy sources? Be able to cite at least two examples. -->
  
==WIND ENERGY==
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 +
There are positive incentives for governments to invest in renewable energy sources.
  
[[Wind generator|Wind turbines]] have been used for household electricity generation in
+
===The Overall Impact on the Planet=== <!--T:27-->
conjunction with battery storage over many decades in remote areas.
+
Most sources of renewable energy pose no noxious by-products (the main exception being the burning of biomass). As a result, there is less pollution, waste, and less of a threat concerning extremely destructive natural disasters.  
Generator units of more than 1 MWe are now functioning in several
 
countries. The power output is a function of the cube of the wind
 
speed, so such turbines require a wind in the range 3 to 25
 
metres/second (11 - 90 km/hr), and in practice relatively few
 
landareas have significant prevailing winds. Like solar, wind power
 
requires alternative power sources to cope with calmer periods.
 
  
However, there are now many thousands of wind turbines operating in
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various parts of the world, with a total capacity of over 20,000 MWe.
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The reality of global warming has also become a considerable factor with regard to the harmful effects of carbon dioxide (CO2) on the balance of the planet’s ecosystem. The less CO2, the better of our planet would be.
New (offshore) windparks are being planned and built all over the
 
world. This has been the most rapidly-growing means of electricity
 
generation at the turn of the 21st century and provides a valuable
 
complement to large-scale base-load power stations. Denmark generates
 
over 10% of its electricity with wind[[turbine]]s. The most
 
economical and practical size of commercial wind turbines seems to be
 
around 600 kWe to 1 MWe, grouped into wind farms up to 6 MWe. Most
 
turbines operate at about 25% load factor over the course of a year,
 
but some reach 35%.  
 
  
==GEOTHERMAL ENERGY==
+
===The Failure of its Technology More Minimized=== <!--T:29-->
 +
The technology used to harness energy from renewable resources is essentially stable. As a result, insurance companies are more inclined to issue warranties for performance of panels and turbines for 20 years or more. Once these items are installed, they can be relied upon to start working straight away and not stop for years.
  
Where hot underground steam can be tapped and brought to the surface
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it may be used to generate electricity. Such geothermal sources have
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potential in certain parts of the world such as [[New Zealand]],
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[[USA]], [[Philippines]] and [[Italy]]. Some 6000 MWe of capacity is
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operating. There are also prospects in certain other areas for
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pumping water underground to very hot regions of the earth's crust
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and using the steam thus produced for electricity generation.
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<!-- 9. What are some of the issues facing the use of renewable energy? What are some of the advantages and potential disadvantages of moving away from fossil fuel energy sources to renewable energy? -->
  
 +
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 +
Although renewable energy has many advantages with regard to its environmental impact, there are concerns that must be considered as well. The ability to supply energy to meet the demand may pose a problem. Providing renewable energy requires designing and building equipment that will harness and extract it once found. The entire manufacturing process must be considered as well.
 +
 +
The general population has grown accustomed to current resources such as oil for heating. As such, although the development of an cleaner, alternative means that present less of an environmental impact may not gain the momentum desired. Some renewable resources have not been around long and tested long enough for individuals to give up what they are comfortable with for something that may be cleaner.
  
==HYDROELECTRIC ENERGY==
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<!-- 10. Individually or as a group, build, not from a kit, a device to harness some form of renewable energy. These devices may include:<br>a. Potato clock<br>b. Solar or wind powered motor<br>c. Hydropower lift<br>d. Your choice. -->
  
===Rivers===
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 +
Note: Internet search engines provide tons of information when you type one of the sources of renewable power and “science experiment.” Thus for hydropower you would search for “hydropower science experiment.”
  
[[Hydroelectric]] power from potential energy of rivers, now supplies
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19% of world electricity. Apart from a few countries with an
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abundance of it, hydro capacity is normally applied to peak-load
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demand, because it is so readily stopped and started. It is not a  
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major option for the future in the developed countries because most
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major sites in these countries having potential for harnessing
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gravity in this way are either being exploited already or are
+
<!-- 11. Brainstorm a list of at least four Biblical texts/stories that illustrate the use of renewable energy. -->
unavailable for other reasons such as environmental considerations.
 
  
The chief advantage of hydro systems is their capacity to handle
+
===Wind - to move ships through the waters.=== <!--T:34-->
seasonal (as well as daily) high peak loads. In practice the
+
{{Bible verse
utilisation of stored water is sometimes complicated by demands for
+
|book=Jonah
irrigation which may occur out of phase with peak electrical demands.  
+
|chapter=1
 +
|verse=4
 +
|version=KJV
 +
|text=
 +
“But the Lord sent out a great wind into the sea, and there was a mighty tempest in the sea, so that the ship was like to be broken.
 +
}}
  
 +
===In Job, Satan used a wind power for evil.=== <!--T:35-->
 +
{{Bible verse
 +
|book=Job
 +
|chapter=1
 +
|verse=19
 +
|version=KJV
 +
|text=
 +
“And, behold, there came a great wind from the wilderness, and smote the four corners of the house, and it fell upon the young men, and they are dead; and I only am escaped alone to tell thee.”
 +
}}
  
===Tides===
+
===Biomass - from firewood=== <!--T:36-->
 +
{{Bible verse
 +
|book=Leviticus
 +
|chapter=1
 +
|verse=6-8
 +
|version=KJV
 +
|text=
 +
“And the sons of Aaron the priest shall put fire upon the altar, and lay the wood in order upon the fire: And the priests, Aaron's sons, shall lay the parts, the head, and the fat, in order upon the wood that is on the fire which is upon the altar.”
 +
}}
  
Harnessing the tides in a bay or estuary has been achieved in
+
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[[France]] (since 1966) and [[Russia]], and could be achieved in  
+
{{Bible verse
certain other areas where there is a large tidal range. The trapped
+
|book=1 Kings
water can be used to turn [[turbine]]s as it is released through the
+
|chapter=17
tidal barrage in either direction. Worldwide this technology appears
+
|verse=10-12
to have little potential, largely due to environmental constraints.  
+
|version=KJV
 +
|text=
 +
“And when he came to the gate of the city, indeed a widow was there gathering sticks. And he called to her and said, “Please bring me a little water in a cup, that I may drink.” And as she was going to get it, he called to her and said, “Please bring me a morsel of bread in your hand.
  
 +
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 +
So she said, “As the Lord your God lives, I do not have bread, only a handful of flour in a bin, and a little oil in a jar; and see, I am gathering a couple of sticks that I may go in and prepare it for myself and my son, that we may eat it, and die.”
 +
}}
  
===Waves===
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 +
{{Bible verse
 +
|book=2 Kings
 +
|chapter=1
 +
|verse=12
 +
|version=KJV
 +
|text=
 +
“And Elijah answered and said unto them, If I be a man of God, let fire come down from heaven, and consume thee and thy fifty. And the fire of God came down from heaven, and consumed him and his fifty.”
 +
}}
  
Harnessing power from wave motion is a possibility which might yield
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much more energy than tides. The feasibility of this has been
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investigated, particularly in the UK. Generators either coupled to
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floating devices or turned by air displaced by waves in a hollow
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concrete structure would produce electricity for delivery to shore.
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==References== <!--T:40-->
Numerous practical problems have frustrated progress.
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[[Category:Adventist Youth Honors Answer Book/Do at home{{GetLangSuffix}}]]
===OTEC===
+
{{CloseHonorPage}}
 
 
[[Ocean Thermal Energy Conversion]] is a relatively unproven technology, though it was first used by the French engineer [[Jacques Arsene d'Arsonval]] in 1881. The difference in temperature between water near the surface and deeper water can be as much as 20 degrees Celsius. The warm water is used to make a liquid such as ammonia evaporate, causing it to expand. The expanding gas forces its way through turbines, after which it is condensed using the colder water and the cycle can begin again.
 
 
 
 
 
==Biomatter & Biogas Energy==
 
 
 
All sorts of biomatter can be burnt to heat water and to drive
 
turbines. Plants partly use [[photosynthesis]] to store solar energy,
 
water and [[CO2|CO]]<sub>2</sub>. Sugar cane residue and other plant
 
matter can be, and is, burnt quite succesfully. The proccess releases
 
no net CO<sub>2</sub>.
 
Offcourse electricity is not the only form of practical energy.
 
In some areas sugarbeets, cane and grasses are grown specifically to
 
produce [[ethanol]] (also known as alcohol) a liquid which can be
 
used in [[internal combustion engine]]s and [[fuel cells]].
 
 
 
Animal [[feces]] release <b>[[methane]]</b> under the influence of [[anaerobic bacteria]] which can also be used to generate electricity. See [[biogas]].
 
 
 
 
 
<h3>Renewable energy needs a reliable and efficient storage
 
system</h3>
 
Sun, wind, tides and waves cannot be controlled to provide directly either continuous base-load power, or peak-load power when it is needed. In practical terms, without proper energy storage methods they are therefore limited to some 20% of the capacity of an electricity grid, and cannot directly be applied as economic substitutes for fossil fuels or nuclear power, however important they may become in particular areas with favourable conditions. Nevertheless, such technologies will to some extent contribute to the world's energy future, even if they are unsuitable for carrying the main burden of supply at this time.
 
If there were some way that large amounts of electricity from intermittent producers such as solar and wind could be stored efficiently, the contribution of these technologies to supplying base-load energy demand would be much greater. Already in some places pumped storage is used to even out the daily generating load by pumping water to a high storage dam during off-peak hours and weekends, using the excess base-load capacity from coal or nuclear sources. During peak hours this water can be used for hydroelectric generation. Relatively few places have scope for pumped storage dams close to where the power is needed, and overall efficiency is low. Means of storing large amounts of electricity as such in giant
 
[[batteries]] or by other means have not yet been developed. See hydrogen [[fuel cells]] below. There is some scope for reversing the whole way we look at power supply, in its 24-hour, 7-day cycle, using peak load equipment simply to meet the daily peaks. Today's peak-load equipment could be used to some extent to provide infill capacity in a system relying heavily on renewables. The peak capacity would complement large-scale solar thermal and wind generation, providing power when they were unable to. Improved ability to predict the intermittent availability of wind enables better use of this resource. In Germany it is now possible to
 
predict wind generation output with 90% certainty 24 hours ahead. This means that it is possible to deploy other plant more effectively so that the economic value of that wind contribution is greatly increased.
 
However, any substantial use of solar or wind for electricity in a grid means that there must be allowance for 100% back-up with hydro or fossil fuel capacity. This gives rise to very high generating costs by present standards, but in some places it may be the future.
 
 
 
===HYDROGEN [[FUEL CELLS]]===
 
 
 
Hydrogen is widely seen as a possible fuel for [[transport]], if certain problems can be overcome economically. It may be used in conventional [[internal combustion engine]]s, or in [[fuel cell]]s which convert chemical energy directly to electricity without flames, in the same way the human body burns fuel. Making hydrogen requires either reforming natural gas ([[methane]]) with steam, or the [[electrolysis]] of water. The former process has [[carbon dioxide]] as a by-product, which exacerbates (or at least does not improve) [[greenhouse gas]] emissions relative to present technology. With electrolysis, the greenhouse burden depends on the source of the power, and both intermittent renewables and [[nuclear energy]] are considered here.
 
With intermittent renewables such as solar and wind, matching the output to grid demand is very difficult, and beyond about 20% of the total supply, apparently impossible. But if these sources are used for electricity to make hydrogen, then they can be utilised fully whenever they are available, opportunistically. Broadly speaking it does not matter when they cut in or out, the hydrogen is simply stored and used as required.
 
A quite different rationale applies to using nuclear energy for hydrogen. Here the plant would be run continuously at full capacity, with perhaps all the output being supplied to the grid in peak periods and any not needed to meet civil demand being used to make hydrogen at other times. This would mean maximum efficiency for the nuclear power plants and that hydrogen was made opportunistically when it suited the grid manager.
 
About 50kWh is required to produce a kilogram of hydrogen by electrolysis, so the cost of the electricity clearly is crucial.
 
 
 
----
 
'''Statistics and facts'''
 
 
 
[[Iceland]] is a world leader in renewable energy due to its abundant hydro and geothermal energy sources. Over 99% of the country's electricity is from renewable sources and most of its urban household heating is geothermal. [[Israel]] is also notably as much of its household hot water is heated by solar means. These countries' successes are at least partly based on their geographical advantages.
 
 
 
----
 
'''References'''
 
*[http://www.uic.com.au/ The Uranium Information Centre] provided
 
much of the original material in this article. *Energy Information
 
Administration provides lots of statistics and information on the
 
industry - http://eia.doe.gov *Boyle, G (ed), '''Renewable Energy -
 
Power for a Sustainable Future'''. Open University, UK, 1996.
 
 
 
[[talk:Renewable_energy|Talk]]
 

Latest revision as of 23:36, 3 January 2023

Other languages:
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Renewable Energy

Skill Level

2

Year

2014

Version

23.11.2024

Approval authority

General Conference

Renewable Energy AY Honor.png
Renewable Energy
Nature
Skill Level
123
Approval authority
General Conference
Year of Introduction
2014
See also


1

What is renewable energy?


Renewable energy is energy whose origins are continually and naturally replenished without human intervention. Examples of renewable energy sources include sunlight, wind, and waves.


2

Why is renewable energy important?


As the demand for energy resources continues to climb, mankind is faced with the dilemma of depleting the earth's resources to meet the demand. With the discovery of processes designed to harness clean and renewable energy, depletion of such resources will not be an issue, since they are naturally replenished. In addition, these processes have much less of an environmental impact than conventional methods used to harness resources such as oil.



3

Describe how each of the following sources is used as a renewable source of energy. Draw an illustration depicting the usage of at least 3 of these renewable sources of energy.



3a

Wind Power


Wind Power is energy that has been converted from the natural movement of wind by the use of devices such as wind turbines. It is clean, largely available, and produces no greenhouse gas emissions.


3b

Bioenergy


Bioenergy is biomass energy, which is energy from organic matter. Wood, plants, even the fumes from landfills can be used as a biomass energy source. Ethanol is a fuel made from corn, sugar cane and other sources used in auto and jet fuel.


3c

Geothermal Energy


Geothermal energy is energy that is created and stored in the earth. It can be used for heating for large areas, mineral recovery, and industrial process heating.


3d

Hydropower


Hydropower is energy that is comes from falling water. Most commonly electricity from dams or run of the river generation turbines is created. Other uses are irrigation and (in pioneer times) falling water was directly harnessed with water wheels for the operation of gristmills and sawmills.


3e

Ocean Energy


Ocean Energy is energy that is comes from the ocean, which can be responsible for two types of energy: mechanical energy from the tides and waves, and thermal energy from the heat of the sun. It can be used for generating electricity.


3f

Solar Power


Solar Power is light and heat that is derived from the sun and collected through solar panels. It can be used to generate electricity for a variety of useful applications.




4

Individually or as a group, discuss some of the earliest forms of renewable energy. Are there energy forms that might have been used before sin? By Noah? By the patriarchs?


The earliest form of renewable energy was probably the burning of biomass in the form of wood and dried animal dung. The fuel could be stored, and energy was available for immediate use, but the energy could not be kept in storage for afterwards.

Some people believe that the pre-flood culture had advanced technologies. Out of place artifacts like machined balls and gold chains inside coal suggest this. Consider how much knowledge a person living hundreds of years and so close to God's perfect creation of Adam and Eve could amass and what they could create with that knowledge. The world had one language as well, and many overlapping generations, facilitating communication.

Additional references are available from the Bible which can provide further insight into this. For example, the sun, the movement of water through rivers, etc.


5

Individually or as a group, show at least five important events in the history of renewable energy through:
a. Presentation
b. Video
c. Interactive game
d. Speech
e. Display


For this requirement, you will need to research the history of renewable energy, and then present your findings using one of the techniques listed in the requirement.

Prior to the development of coal in the mid 19th century, nearly all energy used was renewable. Almost without a doubt the oldest known use of renewable energy, in the form of traditional biomass to fuel fires, dates from the beginning of history.

Probably the second oldest usage of renewable energy is harnessing the wind in order to drive ships over water. This practice can be traced back to ships on the Nile.

The primary sources of traditional renewable energy were human labor, animal power, water power, wind, in grain crushing windmills, and firewood, a traditional biomass. A graph of energy use in the United States up until 1900 shows oil and natural gas with about the same importance in 1900 as wind and solar played in 2010.

By 1873, concerns of running out of coal prompted experiments with using solar energy. Development of solar engines continued until the outbreak of World War I. The importance of solar energy was recognized in a 1911 Scientific American article: "in the far distant future, natural fuels having been exhausted [solar power] will remain as the only means of existence of the human race".

The theory of peak oil was published in 1956. In the 1970s environmentalists promoted the development of renewable energy both as a replacement for the eventual depletion of oil, as well as for an escape from dependence on oil, and the first electricity generating wind turbines appeared. Solar had long been used for heating and cooling, but solar panels were too costly to build solar farms until 1980.


6

Discover the source of most reusable energy.


The source of most renewable energy comes from the sun.


7

What are some commercial and industrial uses of renewable energy?


Renewable energy such as solar energy can be used to supply power larger communities through a solar power station. Tanks of molten salt can be used to store the energy harnessed from the sun for the purpose of generating electricity during cloud cover, or through the night. Renewable energy can also be used for agricultural purposes, providing social services, education, and health care.

Fuel made from bio sources like corn is now a common ingredient in automotive fuel.

Hydro electric power (electricity) is a renewable energy used everywhere the grid goes.


8

Why have many governments invested in renewable energy sources? Be able to cite at least two examples.


There are positive incentives for governments to invest in renewable energy sources.

The Overall Impact on the Planet

Most sources of renewable energy pose no noxious by-products (the main exception being the burning of biomass). As a result, there is less pollution, waste, and less of a threat concerning extremely destructive natural disasters.

The reality of global warming has also become a considerable factor with regard to the harmful effects of carbon dioxide (CO2) on the balance of the planet’s ecosystem. The less CO2, the better of our planet would be.

The Failure of its Technology More Minimized

The technology used to harness energy from renewable resources is essentially stable. As a result, insurance companies are more inclined to issue warranties for performance of panels and turbines for 20 years or more. Once these items are installed, they can be relied upon to start working straight away and not stop for years.


9

What are some of the issues facing the use of renewable energy? What are some of the advantages and potential disadvantages of moving away from fossil fuel energy sources to renewable energy?


Although renewable energy has many advantages with regard to its environmental impact, there are concerns that must be considered as well. The ability to supply energy to meet the demand may pose a problem. Providing renewable energy requires designing and building equipment that will harness and extract it once found. The entire manufacturing process must be considered as well.

The general population has grown accustomed to current resources such as oil for heating. As such, although the development of an cleaner, alternative means that present less of an environmental impact may not gain the momentum desired. Some renewable resources have not been around long and tested long enough for individuals to give up what they are comfortable with for something that may be cleaner.


10

Individually or as a group, build, not from a kit, a device to harness some form of renewable energy. These devices may include:
a. Potato clock
b. Solar or wind powered motor
c. Hydropower lift
d. Your choice


Note: Internet search engines provide tons of information when you type one of the sources of renewable power and “science experiment.” Thus for hydropower you would search for “hydropower science experiment.”


11

Brainstorm a list of at least four Biblical texts/stories that illustrate the use of renewable energy.


Wind - to move ships through the waters.


“But the Lord sent out a great wind into the sea, and there was a mighty tempest in the sea, so that the ship was like to be broken.”
Jonah 1:4 (KJV)

In Job, Satan used a wind power for evil.


“And, behold, there came a great wind from the wilderness, and smote the four corners of the house, and it fell upon the young men, and they are dead; and I only am escaped alone to tell thee.”
Job 1:19 (KJV)

Biomass - from firewood


“And the sons of Aaron the priest shall put fire upon the altar, and lay the wood in order upon the fire: And the priests, Aaron's sons, shall lay the parts, the head, and the fat, in order upon the wood that is on the fire which is upon the altar.”
Leviticus 1:6-8 (KJV)



“And when he came to the gate of the city, indeed a widow was there gathering sticks. And he called to her and said, “Please bring me a little water in a cup, that I may drink.” And as she was going to get it, he called to her and said, “Please bring me a morsel of bread in your hand.” So she said, “As the Lord your God lives, I do not have bread, only a handful of flour in a bin, and a little oil in a jar; and see, I am gathering a couple of sticks that I may go in and prepare it for myself and my son, that we may eat it, and die.”
1 Kings 17:10-12 (KJV)



“And Elijah answered and said unto them, If I be a man of God, let fire come down from heaven, and consume thee and thy fifty. And the fire of God came down from heaven, and consumed him and his fifty.”
2 Kings 1:12 (KJV)



References