Archive for the ‘KellyD’
When you think “Modern Wind Technology”, think of Power Plants.
These power plants include wind turbines that are powered by the wind in order to turn a turbine that powers a generator, and creates electricity that can be used and stored.
To understand the parts of a turbine and how it works, check out the following websites:
One wind turbine generates approximately 2 MW of power.
Wind is less than 1% of the commercial energy market.
-No emissions (CO2)
-Multiple land use because of small footprint
-Could go longer than solar power (because of night and day)
-Noise pollution (from the blades)
-variable wind supply (need storage and backup)
-Some habitat laws (birdstrikes-birds sometimes fly into them)
This is a funny video from class : ) :
Wednesday in class we talked about the common fuels that we use. The three most commonly used fuels include Coal, Oil (Crude Oil), and Natural Gas. When comparing the percents of total energy use in the world to total energy use in the US, 76% of the world’s energy use requires fossil fuels while 85% of the US’s energy requires fossil fuels.
Coal is made up of decayed ancient swamp material which tends to be solid hydrocarbons. Coal can also contain Carbon, Sulfur, Magnesium, and Nitrogen. The top three reserves for coal include 1) USA (27%) 2) Russia (17%) , and 3) China. After coal is mined and extracted from the earth, it is primarily used for electricity generation and steel production. Advantages include: Ample supplies, high net energy yield, low cost, well-developed technology, and air pollution can be reduced with improved technology. Disadvantages include: Severe land disturbance, air pollution, and water pollution, severe threat to human health when burned, environmental costs not included in market price, large government subsidies, high Co2 emissions when produced and burned, and radioactive particle and toxic mercury emissions. Coal is projected to last 200-900 years.
Oil is a liquid mix of hydrocarbons and decayed remains of ocean plants and animals. Oil is also known as Petroleum. The top three reserves that we drill oil from are 1) Saudi Arabia (25%), 2) Canada (15%), and 3) Iran (10%). After the oil is extracted from the earth, it is primarily used for transportation and sometimes asphalt and plastics. Advantages to using oil include: Ample supply for 42-93 years, low cost, high net energy yield, easily transported within and between countries, low land use, technology is well developed, and efficient distribution systems. Disadvantages include: Need to find substitutes within 50 years, large government subsidies, environmental costs not included in market price, artificially low price encourages waste and discourages search for alternatives, pollutes air when produced and burned, releases Co2 when burned, and can cause water pollution. Oil is projected to last for 42-93 years (less than 100 years).
Natural gas is a gas mixture of hydrocarbons that comes from oil and coal. 50-90% is methane along with some propane and brutane. The top three reserves for natural gas includes 1) Russia (27%), 2) Iran (15%), and 3) Qatar (14%). After natural gas is retrieved from the earth, it is primarily used for heating spaces and for cooking. Advantages to using natural gas include: ample supplies, high net energy yield, low cost, less air pollution than other fossil fuels, lower Co2 emissions than other fossil fuels, easily transported by pipeline, low land use, and good fuel for fuel cells and gas turbines. Disadvantages include: it’s a nonrenewable resource, releases Co2 when burned, government subsidies, environmental costs not included in market price, methane can leak from pipelines, difficult to transfer from one country to another, can be shipped across ocean only as highly explosive LNG, and sometimes it is burned off and wasted at wells because of low price. Natural Gas is projected to last 62-125 years.
Hi everyone! Ok so I have been looking at figure 16-10 for a while and need some explaining. So the trash is burned into ash, and then the heat from burning it boils water for energy, and then the ash is disposed of, but what is the Electrostatic precipitator? I guess I just don’t see where that fits in and what it does….and same with the fly ash? Any comments just clarifying would be great!
Hey, I just commented and read James’ scribe post on the discussion of GMO’s. I feel bad asking because you guys may have discussed this in class when I wasn’t there, but are their any regulations or laws that help to solve legal issues with GMO seeds spreading to unauthorized lands? There have to be…I might have just missed them. And you may have discussed how GMO’s can be contained to the owners land if they are causing such issues? If anybody knows a little bit about this let me know…When I think of GMO’s, I think of King Corn… and its hard to think about examples where seeds blow away with the wind and begin to grow on surrounding land. If you feel like answering this, you might want to look at my comment on the scribe post to understand my question a little better!
Ok so on Test 4, number 9…”long-term, large-scale evolutionary changes between groups of species is…” the answer is Macroevolution or Speciation. I guess I am just getting all of these terms confused but could somebody help me easily distinguish between coevolution (which i thought it was), macroevolution, and convergent evolution–These are the ones I mix up and I’m still a little puzzled from the book definitions.
When we were talking today about urban growth either growing up or out, is it fair to say that already developed areas or highly urbanized areas (New York) would grow up if they wanted to expand while those areas less urbanized would grow out first? I feel like I am generalizing this a bit too much because maybe it really does just depend on specific space and available resources (available land). It just seems like those skyscrapers just keep getting bigger and bigger when the newly urbanizing areas don’t seem to start out with large buildings like that from the first step…
After reading the article on rainwater and its runoff, It made me think about the PH scale project that James and I did. We mentioned that rainwater is more acidic (PH value less than 7) than pure water. I was wondering how acidic this rainwater has really become and what point of acidity is too much for typical plants to endure (PH scale). Also, if the acid in our rainwater is combining with pollutants, at what point should we start treating rainwater (PH value) and do we really have the money and time to focus on that?
When studying human population demographics (human population dynamics), the types of studies can be separated into 5 categories:
Currently there are approximately 6.7 billion people in the world (6,700,000,000)
During class we used a cartogram (a map where each country is rescaled to fit its population) to study the population sizes of countries all over the world.
These cartograms all differ in methods of rescaling. The one we used in class made each country up of “blocks” that were supposed to represent a certain number of people. Other cartograms are created in a more fluid picture like the one below:
This is another cartogram that shows the country names (to be more specific):
After viewing these maps, we looked through a population studies book written in 2007 to establish the top 4 most populated countries:
1) China 1.3 billion
2) India 1.1 billion
3) USA 300 million
4) Indonesia 225 million
When attempting to compare population size to surface area size of each country (using a regular map) we were able to rank the top 5 countries in surface area size:
So I was looking at the diagram of the half globe and all the little arrow circles of where air travels in each biome. What I don’t understand is what exactly is this “dry air?” If cool dry air “falls” how is this precipitation if moist air rises? In the picture it shows that the darker red arrows are at the bottom representing cooled dry air that has fallen (which is where the rain symbols are). What? Where dry air is is where the precipitation is?…I feel like I’m making this so much harder than it really is! I think the words dry and moist are messing me up : (