What is Sustainability?

Sustainability

http://www.youtube.com/watch?v=B5NiTN0chj0&feature=related

Sustainability n  Sustainability: Ability to meet current human

natural resource needs without compromising the ability of future generations to meet their own needs.

n  Sustainable Development: Economic

development that meets the needs of the present generation without compromising the ability of future generations to meet their own needs.

How Electricity is Produced

http://www.washingtonpost.com/blogs/wonkblog/wp/2013/03/15/how-the-white-house-thinks-about-climate-change-in-7-charts/

http://www.youtube.com/watch?v=oJAbATJCugs&NR=1&feature=fvwp

Impact of Greenhouse Gases

http://www.e-education.psu.edu/gened/egee101/Examples/102_what_new.html

Renewable Energy Sources

Carbon Footprint

n  A carbon footprint is a measure of human activity on a part of the environment in terms of the amount of greenhouse gas produced.

n  A footprint can be positive or negative n  A carbon offset is conceptually a positive

footprint that represents the mitigation of carbon emissions through improvement projects

How Individuals Can Calculate Their Own Carbon Footprint

http://www.nature.org/greenliving/carboncalculator/

Fuel Cells Ø  Device that uses hydrogen or hydrogen-rich fuel and oxygen to create electricity by an electrochemical process.

Ø Produce much smaller quantities of green house gases & none of air pollutants that create smog & cause health problems.

Ø  More efficient than combustion-based technologies Ø  Variety of sources for hydrogen

http:/www.youtube.com/watch?v=Sncuy89bjCc

PEM Fuel Cell

n  Consists of 2 electrodes & electrolyte n  Hydrogen is oxidized @ anode. n  Electrons released flow via the external

circuit to cathode. n  Oxygen supplied to cathode is reduced by

absorbing electrons. n  Flow of electrons through external circuit

produces electric current.

Oxidation-Reduction Reactions Oxidation (release of electrons)

−+ +⇒ eHH 442 2Anode:

Reduction (absorption of electrons)

Cathode:

Overall Reaction:

ΔG = -237 kJ/mol (@25oC)

OHeHO 22 244 ⇒++ −+

OHOH 222 22 ⇒+