Evan

Week 4: Renewable Energy Renewable Energy Sources:
 * Wind Power
 * Solar Power
 * Hydropower
 * Geothermal Power
 * Biomass Power

Non-renewable Energy Sources:
 * Coal
 * Oil
 * Natural Gas

Non-renewable vs. renewable energy sources: What's the difference?
 * Non-renewable energy- Natural resources that cannot be renewed once they are completely consumed. Resources that are replenished very slowly are also considered non-renewable resources.
 * Renewable energy- Resources that can be renewed or replaced over time.

Although renewable energy may appear to be free (we do not have to "buy" the wind or "buy" the sun), the cost to collect, harness, and transport the energy can be very expensive. Also, renewable resources are non-polluting, a key difference between renewable and non-renewable energy. In the sections below, I will discuss three different types of renewable energy (wind, solar, hydropower).


 * Wind Power: **

The wind can provide humans a nice breeze on a hot, summer day. However, the wind has many other functions as well. The wind, for instance, can change from its initial kinetic energy state to mechanical or electrical energy. Wind is useful because it can turn large grinding stones to grind wheat or corn by using windmills. The wind can also power wind turbines that turn generators to generate electricity. A single, small wind turbine h as the ability to provide all of the electricity needed for a house. A few of these wind turbines (in some cases, only one wind turbine is needed) is sufficient to power an entire school! Imagine how much the electric bill would decrease if humans began to utilize the "free" wind!

Nonetheless, challenges still do exist. Wind is not present 100% of the time, for example. So what happens when wind speed is below 14mph (the velocity necessary for a wind turbine to work efficiently)? That question has yet to be completely answered.

California is a huge proponent of utilizing and harnessing wind power. Currently, about 11% of the entire world's wind-generated electricity is found in California. Moreover, California has multiple "wind farms" located throughout the state. The three "wind farms" that house the most wind turbines are situated in Altamont Pass (east of San Francisco), San Gorgino Pass (near Palm Springs) and Tehachapi (south of Bakersfield). Together, these three locations packed with many wind turbines can generate enough electricity to power the city of San Francisco! Other countries that use wind turbines (and windmills to grind grain or pump water) to create wind energy are Denmark and Germany (among many others).


 * Solar Power: **

Throughout the world's history, we have always payed our respects to the sun. The earliest civilizations--such as Mesopotamia, Egypt, Greece and India--honored and treated the sun as a father figure. Today, we know that the sun is our closest star, and that without it, life would cease to exist (and, of course, it burns our skin!).

The sun's energy, nevertheless, is not utilized to its maximum potential. The United States, for example, uses solar power for only less than 1% of its energy needs. In the future this number is expected to significantly increase due to the development of more efficient and effective solar technologies.

Multiple technologies that capture sunlight do exist and are moderately effective, however. Photovoltaic cells convert sunlight to electricity. Water and other fluids can be provided heat by using flat-plate collectors that absorb the sun's energy. These are only two examples out of the many useful innovations that have been created to harness the sun's power.

There are certain drawbacks of completely turning to solar power. For example, as mentioned earlier, the expense to make the equipment and convert solar power for direct human use is astronomical. Further, solar cells will only operate during the daytime, unlike Coal or Natural Gas plants that will operate for the 24 hour day. Other natural environmental occurences also must be taken into consideration when discussing a "solar powered world". One of theses natural environmental occurences includes the change in seasons. In the Winter, sunlight, although not scarce, is not as apparent (the sun is in the sky for a shorter duration) as it is in the Summer.


 * Hydropower: **

My wikispace post last week briefly discussed how precious water is on our plant, and techniques to increase water availability (including desalination). In relation to renewable energy, water is the most common renewable energy source in the United Sates today.

Hydroelectricity, powered by wind turbines that turn generators to produce electricity, accounts for only 7% of the United States' electricity. A small or micro-hydoelecric power system can produce enough electricity for a home, farm, or ranch.

The rivers and dams near the hydropower plants are not just used by the hydropower plants, however. For instance, increased tourism and industrial and human impact prohibits water to ever be used as the United States' primary source for electricity.

The Tazimina hydroelectic project in Alaska is a concept that has been employed to utilize water as a renewable energy source.

Here is a diagram of a hydropower plant: Also, below is a video about the solar power revolution. I know it is a documentary and it's very long (approximately 48 minutes), the video is extremely informative and get's me (and hopefully you) excited about what the future might bring! media type="youtube" key="nr-grdspEWQ" width="560" height="315"

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Week 3: Water

__ Properties of Water __

 * Universal Solvent
 * Cohesion/Adhesion
 * Surface Tension
 * Liquid more dense than solid[[image:wateruse.jpg width="507" height="287" align="right"]]
 * High Polarity

The world's population grows at an estimated 90 million per year. As our world's population continues to increase, water availability will continue to decrease. That is, if we do not implement any measures to counteract this concern.

A fact that students tend to learn in their childhood is that 70% of the Earth's surface is covered by water. However, a fact that sudents, and even adults, tend not to know is that 97% of our world's water is concentrated in the oceans. This means that only 3% of our world's water is freshwater. And of this 3%, only 1% (0.007% of all of the water on Earth) is accessible for human use. This available water is located in lakes, resevoirs, rivers and shallow underground sources.

Throughout history, water control has been prevalent (and remains so now). Starting thousands of years ago the earliest civilizations, such as Egypt and Mesopotamia, adopted irrigation systems due to water shortages. The shortage of water was not the only problem that persisted, however. Water contamination (fecal matter and other chemicals), especially in the mid-seventeenth to eighteenth centuries, caused many illnesses (including Cholera and Typhoid) and subsequent fatalities. Further, rapid industrialization in the eightenteenth century impacted (and still does, but to a lesser extent) the "quality" of water. To help "restore and maintain the chemical, physical and biological integrity of the nation's [United States of America] waters", the EPA installed the //Clean Water Act// in 1972.

Even though water is one of the most abundant and renewable resources present on Earth, its availability and adequacy has emerged as one of the world's primary resource issues. As a result, new ideas and innovations have been put in place to "create" more usable water. One of these new techniques is called desalination, the removal of salt (especially from sea water). Its purpose is to produce more fresh water suitable for consumption and/or irrigation. Modern interest in desalination is primarily focused on developing cost-effective ways to provide fresh water for human use. Also, like recycled wastewater, desalination is a rainfall-independent water source. Desalination, as a whole, is relatively new and is still being researched. Nevertheless, if desalination becomes successful and widely used, humans will, presumably, not have to worry about water shortages for thousands of years.

<span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">With desalination, the potential benefits greatly outweigh the negatives. However, many challenges still exist. For instance, the energy required to power these desalination plants is enormous. Ironically, most of the power to run the plants is derived from burning fossil fuels. So while you are helping the enivironment, you are simultaneously hurting it. Moreover, desalination plants require specialized and expensive infrastructure in order for the plant to run properly and efficiently. In addition, a study conducted in 2004 deemed that certain areas are, simply put, not suitable for desalination. The conclusion stated, "Desalinated water may be a solution for some water-stressed regions, but not for places that are poor, deep in the interior of a continent, or at high elevation. Unfortunately, that includes some of the places with the biggest water problems."

<span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">As referred to in the quote just above, geography plays a large part in whether a certain area/country can perform desalination. Some of the largest producers of desalinated water today are Spain, the United States, Algeria, China, India, Israel and Aruba. Saudi Arabia, however, is currently the world's number one producer of desalinated water. They use multi-flash distillation, essentially countercurrent heat exchangers, in multiple plants, providing water for many large cities. In the United States, the largest desalination plant is located in Tampa Bay, Florida (it is important to recognize that the output of the desalination plants in the Middle East are much greater than those in the United States).

<span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">Here is a video that discusses desalination (it is a very informative video)! <span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">media type="youtube" key="2XMRlFMJB-g" width="420" height="315"

<span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">So now, after reading some information on desalination, do you think it is a useful innovation? Is it worth the price? And do you think the benefits outweigh the negatives? <span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">I look forward to your input.

<span style="color: #0000ff; font-family: Arial,Helvetica,sans-serif;">Sources: [] [] [] [] [] [] []

<span style="color: #ff0000; font-family: Impact,Charcoal,sans-serif; font-size: 240%;">Week 2: Pesticides


 * What are Pesticides?**
 * Substances used for destroying insects or other organisms harmful to cultivated plants or to animals

__Overview__

 * Why is Pesticide use advantageous?**
 * Consumers receive direct benefits from pesticides through wider selections and lower prices for food and clothing
 * Prevents disease outbreaks through control of rodent and insect populations (protects human health)
 * Used to sanitize our drinking water
 * Used to disinfect indoor areas as well as dental and surgical instruments
 * An effective way to protect private, public and commercial dwellings from damage (to their structures) and rid of infestations


 * What are the cons of Pesticide use?**
 * Suppress particular species of pests
 * Pollute air, water and soil
 * Diminsh biodiversity
 * Reduces Nitrogen Fixation
 * Affects overall human health
 * Linked to neurological and psychiatric complications and even multiple forms of cancer


 * How effective are pesticides?**

As discussed last week, our world's population is growing exponentially. The United Nations (UN) predicts that there will be 1.7 billion more people in the world by 2030. In order to sustain such a large population, we will need to produce large quantities of food. If the United Nation's prediction of the global population (by 2030) is correct, agricultural output will have to double.

Farmland will not grow as the Earth's population grows. Therefore, it is vital that we search and experiment for ways to grow more crops per acre in order to feed the ever-expanding population. However, the production of more food is not the issue (at least not right now). Instead, the problem that we are confronting now is how to fend off pests from destroying our crops. Pesticide use has been employed to try to solve this problem, and it has worked to some degree. First, the European Crop Protection Association has stated that the use of pesticides has increased crop productivity by 20-50%, allowing consumers to choose from an abundant supply of food. Second, we might be able to surmise that without the use of pesticides, crop production will severely drop (the obvious), and thus, the economy could suffer as well. I can make this assumption through the concept of 'supply and demand'. If pesticide use is employed, there will be a steady supply of crops. Therefore, the cost of those crops will stay stagnant (or, perhaps, even drop) and consumers will be able to buy food at a price that is affordable. However, if pesticide use is not integrated, (hypothetically-speaking) supply will drop, and consumer demand will increase. And because the supply of the crops is low, prices will, inevitably, skyrocket to unthinkable highs so the crop companies can make a profit. Furthermore, if we take a look back into history, we could see why pesticide use may be necessary. For instance, the infamous Irish Potato Famine of 1848 was a natural catastrophe of extraordinary magnitude caused by a fungus that still exists today. This fungus, however, is mollified now through the use of fungicides. Although the impact on the potatoes was great, the repercussions from the Great Famine were evidenced in other aspects as well. Its effects permanently altered Ireland's demographic (approximately 1 million people died and another 1 million people migrated to distant lands), political and cultural landscape. Imagine if our world today went through this pandemonium just because we did not use pesticides.

We all know that when there is a positive to something, a negative is almost always associated with it (and the reverse). This statement holds true regarding the use of pesticides. Above, we have discussed the positives, and now, it's time to tackle the negatives (specifically in relation to humans).

Pesticides, no matter how useful they are on a farm, are inherently dangerous. Too much exposure can cause sickness, neurological complications, and even cancer. Certain pesticides "attack" different parts of the body. Organophosphates and Carbamates, for example, affect the nervous system. Other pesticides, such as carcinogens, may cause many forms of cancer. Another side effect of using pesticides is that it mitigates biodiversity because they kill pests.

The Environmental Protection Agency (EPA) is one of the many organizations that examines pesticides and their adverse affects on human health. The EPA, for instance, determines the risk of a particular pesticide by considering the toxicity and the likelihood of exposure (something that we ourselves can control). The EPA is also responsible for determining whether certain pesticide residues left on food is safe for consumption. Moreover, the EPA has developed a table of human health benchmarks for over 350 pesticides that are currently in use, an organized way to determine whether or not pesticide "x" is safe.

The EPA also has completed many experiments that have tested certain pesticides. In 2005, for instance, Dr. Alex Lu and his colleagues from Emory Universirty gathered a group of 3-11 year-olds and substituted their conventional diet with organic-dominated food items. The experiment was testing for the presence for a pesticide called Organophosphate (mentioned earlier), a chemical that affects the nervous system. After the study, Dr. Lu and his colleagues came to the following conclusion: "Immediately after substituting organic food items for the children’s normal diets, the concentration of the organophosphorus pesticides found in their bodies decreased substantially to non-detectable levels until the conventional diets were re-introduced." This experiment shows that if we consume pesticide-free foods, our bodies will have a limited amount of harmful chemicals that are linked to pesticides.

Below are two videos that discuss pesticides and their affects on the environment. The first (on the left), particularly focuses on the chemistry of pesticides, and is demonstrated by a member of the Towson University faculty. The second (on the right) is Dr. Alex Lu describing the experiment he performed (the one I described above).media type="youtube" key="ec9QjNvurRU" width="466" height="299"media type="youtube" key="MkRqaRQRZyo" width="518" height="294"

The question that now remains is whether it is worth to use pesticides to (ultimatley) have greater crop-yields on farms even if there are human health ramifications caused by these very own chemicals. I will leave that for you to discuss.

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<span style="font-family: Impact,Charcoal,sans-serif; font-size: 240%;">Week 1: The Universe


 * The world's resources are decreasing. How can we solve this pressing issue?**

It is widely regarded that humans are the dominant species on planet Earth due to our brainpower and the ability for us to manipulate our planet for the better or for the worse. However, the exponential growth of our world's population is something that we seemingly cannot control. Although countries like China have enacted legislation that limits the amount of children a couple can have (ex: china's "one child policy" due to their staggering and ever-increasing population of 1.3 billion), government policies will not and cannot undermine one's willingness to have kids throughout our world. Therefore, reducing our world's population is not a feasible and realistic answer.

Pessimists forecast that our world's human carrying capacity is approximately 12,000,000,000. They argue that once we reach that point, "humans will be reduced to bare subsistence living," and that our resources will be depleted. The graph below illustrates a pessimist's prediction of our world's global population in the years ahead:


 * So, if we cannot decrease our global population, what exactly can we do?**[[image:global population.png width="486" height="288" align="right" caption="This model predicts that the human population will become extinct by the end of the century"]]

If new technology permits us to artificially produce resources then that would be fantastic; except, the chances of this happening are very slim. Even if we discover new ways to extract resources or find different resources that will replace/substitute the ones that we use now, (theoretically) those will ultimately run out as well. Therefore, scientists (and essentially all humans) raise the question of whether it is time to start to colonize space (the morality of this is a whole different issue). Perhaps, we could relieve some of the pressure on Earth by only living in space temporarily. Of course, by doing this, we are only delaying the time stamp of human extinction due to resource depletion. Thus, we must find a more permanent solution to our growing problem. Perhaps, instead of leaving earth temporarily, we leave it indefinitely. Take a moment and think of how large our universe is, composed of billions of galaxies, and trillions of stars and undiscovered planets (it is hard to appreciate it until one realizes that Earth is only a "grain of sand" compared to a much larger and superior universe). There must be a planet out there somewhere that is suitable for human life, that is similar to the conditions present on Earth. The only barrier prohibiting us from discovering these hidden planets is our current technology. We have made great advancements, but our telescopes and space station is not sufficient. It is time that we actually create the technology necessary to place humans in space shuttles that can travel long distances in a short span of time with little risk. However, the universe itself may contain the "cosmic portals" that will transport space shuttles from point "A" to point "B" in very little time, called wormholes.

Wormholes are purely hypothetical, yet, there is no proof that states they do not exist. Basically, physicists presume that these so-called wormholes are "tunnels" that connect two distant points in space. However, the way in which these wormholes are able to maintain their shape and dimension remains a mystery. Some physicists argue that a wormhole is able to maintain its shape by "creating" negative energy, when the energy density is less than zero (I know, it's hard to understand, but quantum mechanics says it's possible!). Imagine a region of space filled with less than nothing -- this is negative mass/energy. When this negative mass is absent from a wormhole, the wormhole will cease to be traversable because it will instantaneously collapse.

Below are two videos that are very interesting. The first, on the left, is about wormholes (and black holes are discussed), and the second, on the right, is about time travel (wormholes may be a possible vehicle for time travel). Traveling through wormholes via space shuttle may help us reveal the planets suitable for life quicker. Therefore, when humans do run out of resources on Earth, they will be able to exit Earth, enter the wormhole, and land on their new planet in "no time".

media type="youtube" key="HbwvTBaLLqo" width="465" height="280"media type="youtube" key="tNKXi2va2Ws" width="499" height="283"

Additionally, there is an alternative to exploring space. Instead of relocating the human population to a distant planet, we can stay on Earth but still harness the natural resources present in our universe. For instance, after an asteroid called DA14 came within 17,200 miles of our planet in February, a new company called Deep Space Industries said that it would launch a spacecraft in 2015 that will chase down those asteroids that come close to Earth (keep in mind that this is not a defense mechanism, but instead, solely for resource extraction). DA14 is considered an average-sized asteroid, yet it holds approximately $200 billion worth of minerals and water. To put this in to perspective, the global metals and mining industry currently has a value equal to fifteen of these average-sized asteroids. Thousands of these types of asteroids pass by Earth every single day. If we are able to create the technology necessary to harvest our resource-rich universe, Earth's natural resources will, inevitably, become obsolete.

It is important to be mindful that there are various ways to solve or at least delay the depletion of our resources. Space exploration and eventual colonization is only one of the many possibilities. Scientisits may agree or disagree on certain ways to thwart this growing concern, but one thing that everyone must come to recognize is that our resources are gradually decreasing day by day, and it is time that we become more proactive and have a sense of urgency in tackling this issue.

Feel free to leave comments about how you would go about solving resource depletion. I look forward to reading your insight on the subject!

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