1. Biotechnology
Biofuels

2. TNReady Practice Question
Almost half of the electricity generated in the United States comes from power plants that burn coal. Which statement explains the most likely intended benefit for using coal as a source of electricity?
A. Coal is a resource that occurs naturally on Earth.
B. Coal is plentiful and inexpensive compared to other power sources.
C. Some types of coal mining cause harm to the environment.
D. Burning coal releases gases into the air that leads to acid precipitation.

3. Answer B
Explanation- Question is asking for the intended benefit. This would be a positive reason that coal was first invented as a source of energy.

4. Learning objective today:
0607.T/E.4
Research bioengineering technologies that advance health and contribute to improvements in our daily lives.
You are going to learn about bioengineering technologies that contribute to improvements in our daily lives.

5. What’s your job today?
What do you need to learn today?

6. Biomass Video Clip

7. Why do we need Biomass? How Biomass Works (3:23)
What is Biomass (2:57)

8. Video Clip

9. What are Biofuels?
Biofuels are designed to replace gasoline, diesel fuel and coal, which are called “fossil fuels” because they are made from animals and plants that died millions of years ago.
Biofuels are fuels made mostly from plants that have just been harvested.

10. Check for Understanding
Turn to your partner and tell him/her what biofuels are.
Take turns.
Both of you should be talking and explaining to the other.

11. Answers
Need a Volunteer to say aloud what a biofuel is…

12. Three Main Types of Biofuel.
Ethanol, biodiesel, and biojet fuel.
Ethanol is used in engines that burn gasoline, like most cars.
Biodiesel is used in engines that burn diesel fuel, like large trucks and tractors.
Biojet fuel is used in planes. Video Clip:

13. Repeat
Ethanol, biodiesel, and biojet fuel.

14. Check for Understanding
What modes of transportation use:
Ethanol?
Biodiesel?
Biojet fuel?

15. Answers Ethanol is used in cars.
Biodiesel is used in trucks and tractors.
Biojet fuel is used in planes.

16. Are Biofuels Renewable Energy?
To be renewable, an energy force must be able to be replenished easily and quickly and not have a finite limit.
In other words, if it's possible to run out of the energy source, then it is not renewable.
Things like fossil fuels are not a renewable because they take so long to form that we could use all of them much faster than they could be replenished.
Biofuels are considered renewable because they can be replenished as quickly as they are used.
In other words, under normal circumstances we will not run out of energy derived from biofuels.

17. Check for Understanding
What does it mean if energy is renewable?
Are biofuels renewable?

18. Answers
Renewable- energy force must be able to be replenished easily and quickly and not have a finite limit.
Yes, biofuels are renewable.

19. Are Biofuels Better for the Environment?
The jury is still out on this one. Some people say the biofuels are better because the carbon dioxide they produce is taken up when new biofuels crops are grown. So, there is no net increase in carbon dioxide, which is a greenhouse gas.
Other people point out that energy has to be invested into growing biofuels. For instance, land has to be plowed and fertilizer must be applied. When you take all of these factors into account, biofuels actually produce more carbon dioxide than fossil fuels. These people are worried that too much land will be cleared to produce biofuels, which will threaten habitat and cause some plants and animals to become extinct.
Right now, people are trying to figure out how to make biofuel production more efficient so that we get more energy out than we put into growing the crops. This should be possible because most of the energy comes from the sun, so if we cut down on how much preparation is involved, we might be able to ensure that biofuels environmentally friendly.

20. Check for Understanding
What do you think? Are biofuels better for the environment?

21. Do Biofuels Threaten the Food Supply?
This is another tough one. The short answer is yes. Anytime that food crops are not grown because biofuel crops are being grown, there is a net reduction in the amount of food available. This has already caused a problem in some poor countries because the increased use of farmland for biofuel crops means that there is less land available for food crops and this drives up the price of food. In some countries, this has increased the price enough that some people cannot afford as much food.
If we can find a way to grow biofuel crops that is not used for food crops, then we will have solved the threat that biofuels pose to food. However, this may inadvertently increase the environmental impact of biofuels.

22. Check for Understanding
How do biofuels threaten our food supply?

23. Answer
Anytime that food crops are not grown because biofuel crops are being grown, there is a net reduction in the amount of food available.

24. What is Ethanol?
Ethanol is another word for alcohol made from grains. It is the same alcohol that people drink and it can be produced from corn, barley, wheat, grass, sugar cane, and a number of other things.
Ethanol is often used as a biofuel. In most countries, it is mixed with gasoline to create a blend that is sometimes referred to as gasahol. In the United States, the mixture is usually 10 percent ethanol and 90 percent gasoline. This is referred to as E10 and it can be used in any car that burns gasoline. Some cars are known as flexible fuel vehicles or flex fuel for short. These cars can use gasoline that contains as much as 80 percent ethanol. In Brazil, some cars can run on 100 percent ethanol, which is widely available in that country thanks to its abundant supply of sugar cane.

25. Check for Understanding

26. Answer

27. What is Biodiesel?
Biodiesel is a term applied to any diesel fuel that is made by refining oil, fat, or grease collected from plants and animals.
The most common oil used to produce a biodiesel is vegetable oil.
Like gasoline, standard diesel fuel is often blended with a biodiesel.
The most common blend is 20 percent biodiesel and 80 percent regular diesel. This blend is known as B20.
Though B20 is most common, blends can range from 2 percent biodiesel all the way to 100 percent biodiesel.

28. Check for Understanding

29. Answer

30. How much Biofuel is Made Each Year?
About 25 billion gallons of ethanol are made each year for use as fuel.
About 1 billion gallons of biodiesel are produced each year.

31. Biomass Examples
Grasses - A number of different grasses have been suggested as potential biofuel feedstock. The most commonly discussed is Switchgrass. Switchgrass has the potential to be used both directly and indirectly. Its high cellulose content makes it an ideal direct biomass. In some settings it is burned directly whereas in others it is mechanically converted into pellets for easy transportation and storage. As the ability to generate ethanol from cellulosic continue to advance, Switchgrass become a more and more attractive option for this as well. The benefits of switch grass over other biomass include:
Perennial (lowers costs)
Improved soil quality from not plowing each year
Relatively high yield on marginal land not suitable for food production
Drought and pest resistant
Low water and fertilizer needs

32. Corn
The biggest benefit for corn is that it's already grown in relative abundance. The United States is the world leading producer of corn and, not surprisingly, the world leading producer of ethanol made from corn. Each year, a larger and larger percentage of corn produced in the United States is used to make fuel ethanol. Unfortunately, the yield per acre of ethanol produced from corn is relatively low in the net impact of using so much corn to produce fuel ethanol has been an increase in global food prices and bus and increase in rates of starvation.

33. Algae
Algae offers to tremendous benefits over most conventional biofuels.
First, algae are easily manipulated using genetic engineering technology. This allows the organism to be modified to produce more useful oil and to require less nutrients.
Second, algae can be grown in small spaces on marginal land. This means they're less of a threat to the food supply and theoretically could replace the all fossil fuels.
Video Clip:

34. Human Waste into Fuel????
Video Clip1: Africa
Video Clip2: California

35. Cow Poo into Fuel???
E9E9BA9E4E522F

36. Trash into Fuel?
Video Clip: Converting Trash into Electricity (5:48) First 2mins only

37. Three most common uses for biofuels
Transportation
Power Generation
Heat

38. Benefits of Biofuels
Biofuels have several advantages over fossil fuels.
For example, biofuels:
produce less greenhouse gases overall than fossil fuels when they are burned
are alternative sources to fossil fuels - allowing for greater fuel security for countries with little or no oil reserves of their own
may not produce any particulates, such as soot and other fine particles

39. Consequences of Biofuels
Cost
Threat to Food Supply
Land Use
Global Warming
Water
Fertilizers
Monoculture
Video Clip:

40. Global Warming
This probably goes without saying and won't be belabored here, but burning biofuels, which are most hydrogen and carbon, produce carbon dioxide, which contributes to global warming. So, even though biofuels may be able to help ease our energy needs, they won't solve all of our problems.

41. Land Use Changes
This one is little more difficult to understand, but you can think of it as akin to deforestation. If the land used to grow a biofuel feedstock has to be cleared of native vegetation, then ecological damage is done in three ways.
The first way damage is caused is by destroying local habitat. This necessarily destroys animal dwellings, microcosms (micro ecosystems), and reduces the overall health of a region's natural resources. The loss of plant life also means that the world loses valuable CO2 scrubbers. Even though the land is being replanted, a native forest is almost always better at removing CO2 from the atmosphere than a biofuel feedstock, in part because the CO2 remains trapped and is never released by burning as with fuel stock.
The second way that damage is done is in the carbon debt created. Energy is needed to deforest an area and prepare it for farming as well as to plant the crop. All of this leads to the production of greenhouse gases and puts the region at a net positive GHG production before a single biofuel is even produced. Then, energy must be invested into harvesting the replanting the crop the next time around. Estimates have shown that deforesting native land can actually produce a carbon debt that can take up to 500 years to repay. So, using native land for biofuels, even if no food is grown on it, puts us in the hole ecologically.
Finally, as if the two problems above where not enough, changing land to agricultural status almost always means fertilizers are going to be used. It only makes sense to use fertilizer if we want to get the most yield per area. The problem is runoff and other agricultural pollution, which rivals that of urban pollution in its impact on the local environment. Thus, creating more farmland is likely to damage waterways and require us to invest energy into treatment plants and other mitigation strategies. The net result is an even larger carbon debt.
As one can see, land use changes for biofuel production are a very, very bad way to go and should be avoided at all costs. The best solution is to use existing land, but that puts food supplies at risk. So the problem is very difficult to solve. Some people have proposed using algae, which grows in very inhospitable regions and has limited impact on land use. The problem with algae, however, is water use.

42. Monoculture, Genetic Engineering, and Biodiversity
It is easier to grow a large quantity of a single crop if it is all very uniform. This is referred to as monoculture and examples can be seen in the corn, soybean, and potato farming sectors. Potatoes in the U.S., for instance, are almost always Russet potatoes because that is what is in demand by large consumers like fast food chains. The problems with growing a single crop over large tracts of land are several-fold.
First, growing only one crop changes the environment in terms of the food available to pests. This is an evolutionary pressure that can lead to a number of problems. For instance, if a crop of potatoes is eaten by a certain pest that can only migrate a few hundred feet and the potato fields are separated by corn fields, then an outbreak in one potato field is not a problem because it won't spread. Without the corn fields, however, the pest is free to destroy an entire crop.
Now, for the second problem, we could treat the pests mentioned above with pesticide, but it is inevitable that a few of those pests will be resistant. After all, out of the hundreds of thousands or even millions of insects, bacteria, and fungi that can inhabit a single field of crops, at least a few are likely (by chance alone) to be resistant to the chemicals we use to kill them. After all, we can't spray too much as it would be damaging to human health. So the result is a pest that is resistant to pesticide. Now it is free to eat all the crop it wants and we are powerless to stop it.
The next problem comes when we turn to genetic engineering. We decide to modify the crop so that it is resistant to the pest without the need for pesticides. Great! The problem is, the same things happens because it is likely at least a few pests aren't affected by the modification or a new pest comes along and we are left, after a few years, with the same problem as when we began.
The point is, there are limits to how much of a single crop can be grown and there is little that technology can do about that. The key to healthy crops worldwide is biodiversity, which simply means having lots of different types of plants and animals around. That way, if the Russet potatoes suffer blight, we still have Yukon Gold or Red Thumb potatoes to turn to. This is especially important when dealing with food crops. Just ask the Irish and they'll tell you how much havoc a pest can wreak in a food supply built on a monoculture.

43. Food Security
Biofuel feedstock has to be grown and there is only so much suitable land in the world for growing plants. Very little, for instance, is going to grow in the Sahara Desert. The problem with growing crops for fuel is that they take up land that could be used for growing food. In a world with a population of around 7 billion and that is already short on food, there will necessarily be a tradeoff between food crop and biofuel feedstock. Every effort is made to grow feedstock that uses "none agricultural land." This means crops like corn and soybeans are out of the running.

44. TNReady Practice Question
Fertilizers containing phosphorous and nitrogen are leached into a pond. The nutrients from the
fertilizer cause algae colonies in the pond to grow rapidly. As large quantities of algae die, the
pond water becomes depleted of oxygen. What will most likely happen to the pond next?
A. A greater number of organisms will live in the pond.
B. There will be less biodiversity in the pond.
C. The water will become more clear.
D. The depth of the pond will increase.