Class Notes (975,760)
US (383,555)
Berkeley (9,461)
EPS (146)
EPS 7 (22)
Lecture 29

EPS 7 Lecture Notes - Lecture 29: Rapeseed, Biofuel, Canola

2 Pages
67 Views
Fall 2017

Department
Earth And Planetary Science
Course Code
EPS 7
Professor
David Romps
Lecture
29

This preview shows half of the first page. Sign up to view the full 2 pages of the document.
Lecture 29
Biomass power: enough room for food and fuel?
Biomass can be burned in a power plant or in a car
Like the burning of coal, oil, and gas, burning biomass emits H20 and CO2
So, why is biofuel considered carbon neutral?
Biofuel carbon cycle: (a loop)
H2O + CO2 -(photosynthesis) with solar energy O2 + CH2O (with car) and
back to H2O + CO2
Using solar energy
Tera = T =trillion
Trillion W = TERAWATT = TW
For example, 1000 GtC = 1TtC (1,000,000,000,000 chickens)
Global energy consumption
Current 20 TW
What is the maximum potential biomass energy?
1. The area of land is 150 trillion m^2
2. Crops occupy 10% of that: 15 trillion m^2
3. TSI of 1360 W/m2 comes in at the top of the atmosphere
4. Some absorbed some reflected roughly 1000 W/m2 makes it to the surface
5. Another issue: only equatorial regions get 1000 W/m2 head on around noon
- The earth is curved- less dense
- Some areas only get sun at a tilted angle
6. There is day and night
7. Factoring in everything: about 100-200 W/m2 at the surface
8. Plants convert that solar energy into biomass energy with an efficiency of only
< 1%
9. As a result, actual solar harvesting by plants is around 0.5 W/m2
10. Of course, it takes energy to grow crops
- Let us assume that 1/3 of the energy in biomass is used to grow and
harvest the biomass.
- That leaves 2/3 of the energy to be shipped out for other uses
How much possible energy from biomass?
Cropland area: 15 trillion m2
Power per area: 0.5 W/m2
Fraction of energy for sale: 2/3
Total possible power = (15 trillion m2) x (0.5 W/m2) x (2/3) = 5 TW
- Current: 20 TW
- Maximum potential biomass: 5 TW
Two main types of biofuel being used today:
1) Biodiesel
- The U.S. makes most of its biodiesel from soybeans
- Elsewhere, biodiesel is made mostly from rapeseed
- Biodiesel is mostly made of soybean oil and rapeseed oil
- Are these familiar substances? If you cook, yes! Both ingredients of oil
- Canadian scientists Stefanson Baldur and Richard Downey bred
rapeseed to make its oil palatable
- The result: Canadian oil can ola Canola
- Rapeseed flowers and seed pods (images)
- Sample molecule of vegetable oil (soybean or rapeseed) carbon and
hydrogen, separate the chain by chopping off the backbone

Loved by over 2.2 million students

Over 90% improved by at least one letter grade.

Leah — University of Toronto

OneClass has been such a huge help in my studies at UofT especially since I am a transfer student. OneClass is the study buddy I never had before and definitely gives me the extra push to get from a B to an A!

Leah — University of Toronto
Saarim — University of Michigan

Balancing social life With academics can be difficult, that is why I'm so glad that OneClass is out there where I can find the top notes for all of my classes. Now I can be the all-star student I want to be.

Saarim — University of Michigan
Jenna — University of Wisconsin

As a college student living on a college budget, I love how easy it is to earn gift cards just by submitting my notes.

Jenna — University of Wisconsin
Anne — University of California

OneClass has allowed me to catch up with my most difficult course! #lifesaver

Anne — University of California
Description
Lecture 29 Biomass power: enough room for food and fuel? Biomass can be burned in a power plant or in a car Like the burning of coal, oil, and gas, burning biomass emits H20 and CO2 So, why is biofuel considered carbon neutral? Biofuel carbon cycle: (a loop) H2O + CO2 (photosynthesis) with solar energy O2 + CH2O (with car) and back to H2O + CO2 Using solar energy Tera = T =trillion Trillion W = TERAWATT = TW For example, 1000 GtC = 1TtC (1,000,000,000,000 chickens) Global energy consumption Current 20 TW What is the maximum potential biomass energy? 1. The area of land is 150 trillion m^2 2. Crops occupy 10 of that: 15 trillion m^2 3. TSI of 1360 Wm2 comes in at the top of the atmosphere 4. Some absorbed some reflected roughly 1000 Wm2 makes it to the surface 5. Another issue: only equatorial regions get 1000 Wm2 head on around noon The earth is curved less dense Some areas only get sun at a tilted angle 6. There is day and night 7. Factoring in everything: about 100200 Wm2 at the surface 8. Plants convert that solar energy into biomass energy with an efficiency of only < 1 9. As a result, actual solar harvesting by plants is around 0.5 Wm2 10. Of course, it takes energy to grow crops Let us assume that 13 of the energy in biomass is used to grow and harvest the biomass. That leaves 23 of the energy to be shipped out for other uses How much possible energy from biomass? Cropland area: 15 trillion m2 Power per area: 0.5 Wm2 Fraction of energy for sale: 23 Total possible power = (15 trillion m2) x (0.5 Wm2) x (23) = 5 TW Current: 20 TW Maximum potential biomass: 5 TW Two main types of biofuel being used today: 1) Biodiesel The U.S. makes most of its biodiesel from soybeans Elsewhere, biodiesel is made mostly from rapeseed Biodiesel is mostly made of soybean oil and rapeseed oil Are these familiar substances? If you cook, yes! Both ingredients of oil Canadian scientists Stefanson Baldur and Richard Downey bred rapeseed to make its oil palatable The result: Canadian oil can ola Canola Rapeseed flowers and seed pods (images) Sample molecule of vegetable oil (soybean or rapeseed) carbon and hydrogen, separate the chain by chopping off the backbone
More Less
Unlock Document
Start your 2 week free trial

Only half of the first page are available for preview. Some parts have been intentionally blurred.

Unlock Document
Start your 2 week free trial
You're Reading a Preview

Unlock to view full version

Unlock Document
Start your 2 week free trial

Share with your friends

Get 2 friends to sign-up for a free trial as well, and get an additional free week

Next

You've reached the limit of 4 previews this month

Create an account for unlimited previews.

Already have an account?

Log In


OR

Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit