Lets understand energy sources some more: Table

 http://www.cbs.nl/en-GB/menu/themas/industrie-energie/publicaties/artikelen/archief/2007/2007-2187-wm.htm

convert Euro to dollars

http://www.nrel.gov/

http://energylinx.co.uk/gas_meter_conversion.html

http://en.wikipedia.org/wiki/Energy_density

Carbon Capture & Storage-Netherlands

Economy of the Netherlands

http://www.world-nuclear.org/info/inf107.html

Energy Information Administration

What is the current profile of energy use in the US and the World? Can the current energy consumption profile last?

The United States' energy consumption is approximately 250 kWh/d per person and was determined from a chart provided be our professor.

The world energy consumption was a bit harder to calculate. It was first found that the energy consumption in 2008 for the world was 474 exajoules.

1 exajoule = 2.78 * 10^11 kWh
474 exajoules = 1.3167 * 10^14 kWh

Assume the population of the world in 2008 was 6.9 billion people.

(1.3167 * 10^14 / 6.9 * 10^9) / 365 days = 52.3 kWh/d per person

The current energy consumption profile in the United States and in the world can not last and will not last unless changes are made.

Transportation and Decision Making. Is Energy a Personal Issue or a Public Issue?

Most people would agree that energy is a public issue rather than a personal issue.  Our use of fossil fuels in transportation will not decrease because of individual choices.  A decrease in consumption will be seen when a drastic change is made in how we travel.  Right now everyone can do their own part to make a difference but in reality they are not even making a dent. Things will start happening when people are made to do their part. For example, at some point the public will not have the personal choice to buy a hybrid or electric car because all cars will be hybrid or electric.  If/when this happens everyone will be making a difference because a change has been made on a public level rather than a personal level.

Real Issues vs Fake Issues

The main issue, if it was unclear, is our dependence on fossil fuels and our lack of renewable energy sources.  This is a real issue that needs to be resolved.  McKay does a good job of describing fake issues that keep this from happening.  These fake issues include how geothermal is immature, offshore wind could affect radar, shallow offshore wind can kill birds, normal wind takes up too much space and solar heating doesn't belong in the street.  McKay shows statistics about the causes of bird deaths to prove that it is a fake issue.

As you can see, the number of birds being killed by windmills is negligible and a worthwhile sacrifice.  The fake issues will need to be acknowledged and put to rest if the world wants to achieve a greater goal.

What is Feasible?

McKay concludes his red stack/green stack by talking about much energy Britain could feasibly get from renewable sources.  He expresses his frustration towards the public and how their concerns make renewable energy sources seem like an inconvenience.

 

He concludes that only 18 kWh/d per person could be generated using renewables and that 125 kWh/d per person is consumed.  It is clear that two things need to happen if we can expect to power our world with renewable energy.  The public needs to embrace new forms of energy production, even if they are a minor inconvenience, and consumption needs to decrease.  If these things happen it may be feasible to power our world using renewable energy.

What is the embodied energy in an apple?

First lets define embodied energy.
Embodied energy is a term used to describe all the energy that goes into the life cycle of a product including manufacturing, transporting, and disposal.

Using California:
First, we consider that apples are sourced within California during the harvest season. Thus only minimal storage time is required, resulting in no yield loss. The energy consumed during storage and transport is 3.4 MJ/kg, resulting in .233 CO


Local apples that are sold out of season:
  The embodied energy is 6.8 MJ/kg of energy used, resulting in .431kg CO

Apples grown in New Zealand and shipped to California in season

Embodied Energy of an Apple

      Figure 1. Embodied Energy of an apple-in season. Units are MJ/kg

       Fig 2. Embodied Energy of an apple-out of season. Units are MJ/kg

     Fig 3. Embodied Energy of an imported apple-in season. Units-MJ/kg

Transport and storage of these imported, in season apples takes 4.6 MJ/kg of energy, resulting in .34 CO

Apples grown in New Zealand and shipped to California out of season-long term storage

     Fig 4. Embodied Energy of an imported apple-out of season-Units MJ/kg

8.23 MJ/kg of energy used during storage and transport, resulting in .56 kg CO

we assume California apple production has an energy profile of 1.2 MJ/kg. In reality, such energy usage is likely to vary between producers based on factors such as irrigation usage and harvesting techniques

Comparing the Energy Intensity of Scenarios:
MJoules required to Produce, Transport and Store 1 Kilogram of Saleable Apples

         Figure 5. Total Embodied Energy of an Apple

Energy Out:A small apple has about 53 calories and weighs 3.6 ounces.
3.6 ounces = .102kg
53 calories = .220MJ
Therefore the available energy from eating an apple is .220MJ/ .102kg = 2.15MJ/kg
However we only use about 20% of that energy to do actual work.
Energy Out = .43MJ/kg

Summary: Grow your own apples or you are wasting way more energy than you get back from the apple.
                If you care, grow an apple tree in your yard. If not, drink a beer.

Red Stack / Green Stack



The total for the red stack is 150 kWh/day
The total for the green stack is 125 kWh/day