Clean Energy

Westmill co-op

Learning Objectives

  • Evaluate current technologies to produce clean energy.
  • Identify future directions for economically sustainable clean energy.

Agenda

  1. Review Exam 1 (15 minutes)
  2. Review Energy Flow Graphic (10 minutes then discussion 10 minutes)
  3. Activity - Clean Energy Your Choosing (25 minutes, 20 minutes)

 


Energy Flow

Review and analyze the National Academies' interactive flow graphic of our energy system 

Answer the following questions:

  • What sector wastes the most energy? And what is one idea to reduce this waste?
  • US is projected to increase electricity generation 11% by 2040. How many total quadrillion BTUs is this? On the current trend where is the majority of this energy going to come from? What is the second highest?
  • What does 1 Quadrillion BTUs of energy mean for the average person? Put this in terms of something we can all understand - i.e. number of cars, number of lightbulbs, etc..
  • The regional energy system relies a lot on coal. But California does not. What energy sources does California replace with coal?

Clean Energy - Your Choosing (Discussion)

  1. Chose a clean energy source you are interested to learn more about - solar, wind, biofuels. 
  2. Complete the tasks for that section below in groups of two.

Solar  

"I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait till oil and coal run out before we tackle that." - Thomas Edison 

Depending on who you listen to, solar energy is the only solution we need to our energy challenge (doubtful). Others argue (incorrectly) that a solar panel takes more energy to produce than it will ever generate. I just want you to have a fact-based opinion on this topic.

Discussion:

For a home you care about (could be the one you grew up in, the one you live in now, the one you hope to live in in the future, etc...), calculate the cost and benefit of using the following technologies. A google search will turn up a number of calculators, just try to pick one that is somewhat unbiased (a company selling solar panels is going to give you a best-case scenario). Post all 3 of your results to Discussion Clean Energy Source Links to an external site. and include anything you are skeptical about.

  1. Off-grid Solar Photovoltaic (this will include storage costs) 
  2. Grid-tied Solar Photovoltaic
  3. Solar Water Heating (be sure to include any rebates)

Wind

“When the wind changes directions, there are those who build walls and those who build windmills.” – Chinese proverb

Like solar, wind energy does not produce climate-changing emissions. Also like solar, the feasibility of wind energy depends on location and weather. I personally think windmills are beautiful and quiet, especially compared with some of the other things we build. Not everyone agrees, so wind energy is susceptible to the "not in my backyard" argument.

Discussion:

Use this Wind Calculator Links to an external site. to determine whether a wind turbine is a good investment at the location where you grew up. What changes in variables (cost of electricity, cost of turbines, etc...) would make investing in wind a more attractive option? Post your responses: Discussion Clean Energy Source Links to an external site..

Bio-Fuels

“The US imposes a .54 $/gal tax on sugarcane ethanol and a .0125 $/gal tax on gas.” Tom Friedman in Hot, Flat and Crowded 

Biofuels are already being made from all types of sources, from palm oil to sugarcane to switchgrass. Growing our own energy is certainly an appealing proposition. But, how much can we really expect to produce this way? How can we produce biofuels without impacting food crops (see tortilla riots Links to an external site.)? In this module you will evaluate the potential contributions of biofuels to our energy mix.

Discussion

Biofuels can be made from sources grown specifically for that purpose (e.g. switchgrass, algae). They can also be produced from the "waste" products of other processes. Identify a potential source of this second type of biofuels in your area. This could be anything from used cooking oil...to peaches Links to an external site.

For the source you have identified, post estimates of the following to Discussion Clean Energy Source Links to an external site. (The key word is "estimates", don't spend more than 2 hours on this):

  1. How much supply is available? For example, how much oil do restaurants in your town go through? How many pounds of waste peaches are there?
  2. How much energy could be produced by this supply? There are many calculators available online. You can probably find one specific to your source, but here are some examples: Biofuels B2B, Links to an external site. Biomass to energy calculator. Links to an external site.
  3. What are the downsides to using this source of energy?

Discussion

Read Carbon Zero - Chapter 2: Why clean energy isn’t enough Links to an external site.. Post your thoughts about clean energy based on the reading and class lecture. Questions that you could consider answering: Is clean energy the solution? If not how do we get there? What should we do today, next year, 5 years, 20 years from now related to clean energy? 

Assignment 

Watch two videos associated with a renewable energy you did not research during class:

About Solar:

About Wind:

About Bio-Fuels: