PDS AP Environmental Science 8th Period 2011-12

Since it is so close to the AP exam and all of you have fulfilled your scribe post obligations, I won’t start the list over.  So, here is a collection of links from past classes on major air pollution issues and global climate change for those that missed class. While written a year or two ago, all the info is still correct and relevant:

Acid Rain

Ozone

Intro to Global Climate Change

Global Climate Change

Evidence and Consequences (of the Earth’s Warming)

Solutions to the Earth’s Warming Problem

Tags: air pollution, atmosphere, carbon, climate, fossil fuels, nitrogen, ozone

After testing a handful of vehicles in each class, we tried to analyze the class data for trends.  It has become harder and harder to do as vehicle emissions have become so much “cleaner” over the last decade (yes, I said it). If we had the time, this is the data I would love to gather:

Relationship between CO2, CO, HC (Click to enlarge)

One reason vehicles emissions have improved so greatly in the USA, is catalytic converter technology. Catalytic converters speed reactions to reduce the amount of NOx, CO, and HC coming out of an automobile.  Check out how catalytic converters work at howstuffworks.com.

Catalytic converters are pollution solutions!

Why does all this matter? Well, NOx have a key role in the formation of ground-level (tropospheric) ozone and photochemical smog. Reduce NOx (and CO and HC), and you reduce ground-level ozone and photochemical smog. You need to be familiar with both types of smog (below) on the AP exam.

Smog Types

Tags: air pollution, atmosphere, carbon, fossil fuels, nitrogen, ozone

Monday we began talking about what exactly comes out of our cars, why they can be dangerous, and what the government is doing to curb these emissions.

We talked first about the Clean Air Act of 1970. This act allowed the E.P.A. through the NAAQS or the National Ambient Air Quality Standards.

These standards were set on 6 “criteria” pollutants: NOx O3 SOx CO Lead and Particulates

The Actual Set Standards

We then focused on why there were standards set on these pollutants

Mr Williard's Highly Detailed and Highly Skilled Sketch

We divided the car emissions into two categories: regulated and non regulated.

Non Regulated

• N2 is non regulated and not harmful, because it is relatively inert and passes through the car without any reaction
• C02 is a warming gas that is created by reacting with C8H18 or Octane. It seems likely that there will be CO2 regulations in the future
• H20 is also created in a reaction but is benign.

Regulated

• CO= Very toxic
• HC or hydrocarbon is an unburned fuel which is also known as a VOC or a Volatile Organic Compound
• Particulates are what come from the exhaust to form Smoke or Smog
• NOx is more dangerous as a secondary pollutant. When NOx combine with O2 due to high energy from temperature, creating O3 or Ozone.

Finally we talked about how the government can warn us about the quality of air at the current time through the Air Quality Index

AQI Index

Sources

http://www.blogmyair.com/uploaded_images/aqi-759020.JPG

http://www.intellectualtakeout.org/sites/www.intellectualtakeout.org/files/naaqs.jpg

Tags: air pollution, atmosphere, carbon, fossil fuels, gasoline, nitrogen, oil

Before Mr. Thompson, the CEO of a Biodiesel fuel company, came to speak to us on Friday, what did our class know about Biodiesel fuel or even just diesel fuel? We knew that diesel fuel was more expensive at gas stations than gasoline, that trucks and other large vehicles often run on diesel fuel, and that diesel fuel would destroy a gasoline engine. But that was about it.

The first thing Mr. Thompson want to make clear to us was that BIODIESEL IS NOT ETHANOL. Ethanol is a corn-based fuel that is made by distilling the sugars and starches into alcohol. It is then mixed with gasoline. Ethanol is not only less efficient than gasoline but it also takes away from our food supply. Basic rule of economics: when the supply of a product decreases the price increases. On top of its lack of efficiency and the fact that it increases the price of food, because it is corn-based all the same fossil fuel inputs and environmental impacts associated with farming. When you add up all these costs ethanol is energy negative (it takes more energy to make it than it provides) and in the eyes of Mr. Thompson and many others to be a bad fuel.

Mr. Thompson went on to explain what biodiesel fuel actually is and does. Biodiesel is fuel made from natural oils (soy, canola, poultry, algae, or Mr. Thompson’s company made fuel from used cooking oil) that can be used in a diesel engine. It can be combined with petroleum-based diesel fuel in any percentage and still run a diesel engine. In fact, the main reason biodiesel even needs to be mixed with petrodiesel fuel is that it tends to congeal when it is cold and block up engines. Petrodiesel’s lower freezing point prevents this tendency when the two are mixed. Compared to regular diesel fuel biodiesel fuel can also reduce carbon emissions by as much as 75%.

Biodiesel: 30 PSA

Just a couple of videos to show you how biodiesel fits into our country today

Mr. Thompson finished his lesson by telling us what biodiesel is not. Again IT IS NOT ETHANOL. It is not simply waste vegetable oil taken from someones kitchen and dumped into a gas tank. It has to be processed first or else it would eventually ruin your engine. On the downside, in most places it is not cheaper than regular diesel fuel or gasoline or available in as great quantities… yet. But on the upside it is not flammable, hazardous, carcinogenic, and since it is just natural oils, it biodegrades very quickly.

Biodiesel fuel has many exiting possibilities and in a few decades it could be one of our major sources of fuel.

Mr. Willard's picture

Tags: biodiesel, biofuel, biomass, energy, renewables

For the first part of Monday’s class, we discussed various ways to conserve energy in our homes, in transportation, and in energy generation.

At home:

• Energy Star Appliances
• Check insulation/Fix leaks
• Turn the thermostat up in the summer and down in the winter
• Use power strips to reduce vampire load aka phantom load
• BULB CHOICE-Even though many bulbs may seem more expensive at the store, they actually save you more money in the long run.

• CAFE Standards to increase fuel efficiency

Generation:

• We would like a high EROEI (Energy Returned on Energy Invested) value

For the second part of class, we discussed a number of ways to calculate energy problems.

*CLICK ON THE PICS TO ENLARGE*

The first equation is about energy and power:

We must remember that one watt is a very small unit, and it is much more common to see homes and factories using kilowatts or megawatts.

1W= watt         1KW=Kilowatt=1,000 watts        1MW=Megawatt=1,000,000 watts

The second equation is about heat transfer:

There are two different versions of this equation, the Metric version and the English (industry standard) version.  They are the exact same equation, except for the units.  We must also remember that the specific heat of water (the energy required to change the temperature of water by one degree celsius) is always 1.  This is important because many home appliances and power plants heat water for various reasons.

The third equation is cost:

This is just a simple equation used to determine the total price paid for more than one product.

The fourth and final equation is efficiency:

This equation tells us how efficient a type of technology (light bulb, wind turbine, etc.) is.  A higher level of efficiency is obviously the more desired amount.

Tags: energy, math

Have you ever thought about how much electricity is needed to supply the lively city of New York?  Just think about all of that electricity, and how it is made.  Have you ever seen wind turbines in the Big Apple?  Well, in the next few years you might. Check out this New York Times blog post about how New York plans to utilize its renewable energy found offshore.

Wind energyis the fastest growing energy source, because it is cheap, clean, and it is also a non depletable resource.  It is really quite simple how they work.

It's Easy!

According to our APES textbook, the United States has the largest wind energy generating capacity in the world, but we obtain less than 1% of our electricity from wind.  Why wouldn’t we utilize this clean energy?  Check out this video that shows how quickly wind farms are popping up all across the United States and the world, and that explains the advantages of using this energy.

Sources:

http://green.blogs.nytimes.com/2012/03/20/for-new-york-a-map-of-viable-offshore-wind-power/?ref=windpower#

http://windy-future.info/wp-content/uploads/2009/10/how-a-wind-turbine-works-0374.jpg

http://videos.howstuffworks.com/siemens-corporation/2950-wind-power-the-worlds-fastest-growing-energy-source-video.htm

Tags: energy, renewables, wind

   Apple Data Center puts Charlotte in national spotlight as the debates over hydrogen fuel continues! Trying to become the nation’s “greenest” and “most technologically advanced” company, Apple recently has declared that they are fueling their new data center in suburban Charlotte solely from hydrogen power. While no one is faulting Apple for trying to use this very clean source of energy, a conflict of interest debate has come up and Apple is facing heat from the press.

As gas prices have continually climbed over the last decade or so, hydrogen power has long been regarded as the “energy of the future.” Pictured below, the chemical equation of hydrogen power shows why many people have begun to support research and development of this clean energy.

2 H2 + O2—-> energy + 2 H20

    Because energy and water or the only byproducts of this chemical reaction, it’s not hard to see why many Americans say they would prefer the use of hydrogen fuel cells rather than dirty, greenhouse gas emitting gasoline or coal. But, at this period in time there are a number of reasons prohibiting us from seeing widespread use of hydrogen fuel cells.

1. It currently takes more energy to yield pure hydrogen then the cells omit when they are used.

2. Fossil fuels are the main source of energy used when trying to yield pure hydrogen.

3. The process used to “take the energy” is very complicated (as shown in the video below) and it would be very expensive to convert all formerly gasoline run systems to this process.

http://www.youtube.com/watch?v=6UwSazq8GTU

4. Lastly, the use of hydrogen fuel cells, especially in automobiles is impractical. Hydrogen either has to be..
a) Kept at very high pressures, which would cause fuel cells to be much larger than their gasoline tank counterparts to hold the same amount of potential energy. Or
b) Kept at very low temperatures to keep the hydrogen in its liquid form, which is infeasible considering our cars often spend long periods of time in warm weather.

Sources:

http://www.foxnews.com/scitech/2012/04/09/apples-hydrogen-power-plans-fueled-by-al-gores-conflict-interest/

http://images.apple.com/environment/progress/images/maiden_facility.jpg

http://www.youtube.com/watch?v=6UwSazq8GTU

http://www.chicagotribune.com/business/ct-biz-0404-apple-fuel-cells-20120404,0,7442283.story

Tags: energy, hydrogen, renewables

Pikachu, quick use thunderbolt!

Critical Hit!

Foe’s Blastoise fainted.

For the millions of you that have played Pokemon, it seems obvious that electricity is water’s kryptonite; they don’t mix! But in the world of modern science, nearly twenty percent of all electricity comes from hydroelectric plants (imagine that Ash!). Source: Friedland and Relyea Environmental Science for AP

To illustrate the vast potential of Hydroelectricity as an alternative energy source, check out this brief video of China’s Three Gorges Damn, the largest in the world.

Here’s a current article about the dam!

Hydroelectric power uses dammed reservoirs to direct the flow of water through a penstock and then past a turbine that generates electricity. Watch this short video to see what I’m talking about, and if you don’t have time for the video, check out the diagram.

Diagram

Hydro electricity takes “hydro” and a substantial initial investment, and not all countries have the water and resources to make hydroelectric dams. The good new is that hydroelectricity emits no pollutants once constructed, and there are other ways to generate the hydroelectricity without a large river such as, run-o-the-river and tide. These use the same concepts, but don’t have reservoirs to direct the flow.

Get it? Got it? Good.

P.S.

Things to consider:

fish ladders: for migratory fish during their mating season.

Siltation:  the plague o’ hydroelectric dams! Silt from the water builds up behind the dam and has the potential to clog the penstock.

Tags: energy, renewables, water

STOP! Before you read the rest of this blog post, sprint down a flight of stairs and run back up again as fast as you can. GO!

Okay, so how do you feel now? A little hot? Congratulations, you just got a little bit of exercise and experienced the same heating concept that is used in Geothermal Energy.

David Blackwell, SMU’s chief geological expert, recently gave a briefing to congress about the future of alternative energy sources in the United States. It was part of a series on the science and technology needed to achieve the United State’s energy goals titled, “The Road to the New Energy Economy.” Blackwell explained that geothermal is going to play a major part in our energy security in the future, and the US is in a prime position to lead the world in conventional and emerging unconventional geothermal techniques. Slowly but surely, the world is beginning to understand the importance of reducing our dependance on fossil fuels, and geothermal energy is going to play a major role in that transition.

Geothermal Energy is a way to produce energy that combines the use of a renewable resource and drilling. Geothermal energy utilizes the heat that comes from the earth’s core. Think about water that is naturally heated such as the water from “Old Faithful.” This spring is heated by convection currents bringing magma from the earth’s mantle to the earth’s crust. Heat and pressure builds up in the spring causing it spew out at temperatures up to 200∘F. Geothermal energy uses the same concept in order to heat homes or turn turbines.

How do you harvest Geothermal Energy?
Remember running up and down those stairs? Water goes through this same journey as it is pumped or circulated underground. As water comes back up, it can be piped into household radiators and has the potential to heat a home. But this heat also has the potential to produce electricity. After the water cools, the cycle repeats, constantly using the earth’s natural heat. So you may have not been as winded when you ran down the stairs, but you may have felt the heat coming back up.

Water moves through this system and can be recycled as well.

How does Geothermal Energy produce electricity?
As water is pumped into the ground, the water is heated and can be pumped, or naturally flows, into a plant where the water is converted into steam. This steam is then used to turn a turbine, used to generate electricity. It’s the same concept as a coal fired power plant but instead of burning coal, you’re heating the water with renewable energy. Some of these power plants drill up to a thousand feet underground just to generate enough energy so some of these plants are not suited for areas.

Video explanation of Geothermal energy:

Geothermal-Energy-Process.aspx

Is Geothermal Energy good for the environment?
Yes! Geothermal energy is a renewable resource so it reduces the amount of fossil fuels we use, which reduces the amount of greenhouse gases we produce. Geothermal energy also produces little to no pollution.
Geothermal energy is also economically beneficial. It not only provides jobs, but it is also 80% more cost effective than using fossil fuels. It reduces our dependence on fossil fuels.

Is Geothermal Energy bad for the environment?
Unfortunately it can be but not as much as non-renewable resources. The water that is pumped underground can be influenced by dangerous chemicals that can seep from the earth’s crust.
Geothermal energy can be more inconvenient rather than environmentally detrimental. Some areas aren’t suited to pump water underground. And although this energy is cost-effective compared to fossil fuels, the cost to design, build, and staff these plants is very expensive.

Which Countries Produce and Use Geothermal Energy?
Many countries in the world have begun producing geothermal energy, the three largest producers being the United States (3,086 MW), the Philippines, and Indonesia. The worldwide capacity of geothermal electricity production is about 10,715 MW, with about 10 countries producing the vast majority of that energy. As a percentage of total electricity use, Iceland is the largest user of geothermal electricity (almost 30% of total electricity is produced geothermally!). 100% of their total electricity is renewable; the other 70% is hydroelectric.

Source:
http://www.conserve-energy-future.com/Advantages_Disadvantages_GeothermalEnergy.php

Tags: energy, geothermal, renewables

This article shows the future of solar energy in Africa by providing cleaner and more accessible energy to the impoverished communities.
The article mentions that the only current source of energy and heat is burning wood and coal which can cause tuberculosis and asthma. The transition utilizes solar powered hot water heaters and clean-burning cooking stoves which are types of active solar energy. This is a unique example of how solar energy can improve the health of less fortunate societies through Active Solar Energy. The other main method of solar energy is Passive Solar Heating. The major difference between the two types of solar energy is that passive solar heating doesn’t require the use of mechanical and electrical devices like active solar energy does.

Passive Solar Heating is used to collect, store, and distribute solar energy in the form of heat in the winter while also to reject solar heat in the summer. This technique takes advantage of the building design, but the designing must be done during the construction of the house or building. Examples of the building designs are things like positioning windows on the south-facing walls to let sunlight and heat in, covering roofs with dark material to maximize heat absorption, and having overhangs to block sunlight in the winter.

Here is a visual to passive solar heating:

This is a video that better explains how window positioning helps passive solar heating.

*While you don’t have to spend extra money on equipment, construction costs can run high but usually pay themselves off within a few years.

Active Solar Energy is used to convert solar energy into a more useful form of energy, such as heat or electrical energy. Examples of active solar energy are things like a small scale water heating system, photovoltaic solar cells, and large concentrating solar thermal systems. Water Heating Systems can be used for household water, public swimming pools, or businesses and is generally driven by a pump that is powered by the sun. A Photovoltaic Solar Cell is an electrical device that converts the energy of light directly into electricity. Many of the solar cells are paired together to make the solar panels that are seen on houses and buildings. Concentrating Solar Thermal Systems use mirrors or lenses to concentrate a large area of sunlight, aka solar thermal energy, onto a small area which then converts the light to heat. This drives the turbine that is responsible for generating the power.

*Active solar energy can generate hot water or electricity without polluting the air or water as it doesn’t produce CO2, but the installation of these technologies can be expensive.

Tags: energy, renewables, solar