Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

Energy Consciousness Energy Consciousness and Conservationand Conservation

Focus the Nation, 2009

Professor Stryker, Department of Mechanical Engineering

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

Energy ConsciousnessEnergy Consciousness Making correct choices about energy use.Making correct choices about energy use. How do you know the choice is correct?

What to consider:1. source – where does it come from?2. sink – where does it go?3. social costs and implications4. political costs and implications5. economic impact

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

How we heat water:How we heat water:1.1. Burn coalBurn coal2.2. Heat water to very high Heat water to very high

temperature and pressure steamtemperature and pressure steam3.3. Use the steam to turn a turbine Use the steam to turn a turbine

which drives an electric generatorwhich drives an electric generator4.4. Transport the electricity to your Transport the electricity to your

hot water heaterhot water heater5.5. Heat the water in the tankHeat the water in the tank6.6. Transport the water to your Transport the water to your

shower and mix with cold watershower and mix with cold waterIs this the best use way to use Is this the best use way to use

energy to heat water?energy to heat water?

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

Energy ConservationEnergy Conservation

First Law of ThermodynamicsFirst Law of Thermodynamics

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

1st Law of Thermodynamics: 1st Law of Thermodynamics: Conservation of EnergyConservation of Energy

Energy stored in the SystemEnergy

Transferred In

EnergyTransferred

Out

Ein – Eout = dEsystem/dt

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

What is the system?What is the system?An automobileAn automobile

•What is the energy ‘in’ for each of the systems?•Is there a limit to the supply?•What are the implications of a limited supply?

The Earth

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

Where does the energy ‘out’ go?Where does the energy ‘out’ go?

What is a sink?What is a sink?

Are sinks important?Are sinks important?

How much can you put in How much can you put in the sink?the sink?

What affects the rate of energy out?What affects the rate of energy out?

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

EconomyEconomy

The economy is a subsystem of the The economy is a subsystem of the earth.earth.

The energy available to enable The energy available to enable economic activity is finite.economic activity is finite.

A sustainable economy requires A sustainable economy requires sustainable management of the sustainable management of the energy resources.energy resources.

Focus the Nation, Prof. StrykerFocus the Nation, Prof. Stryker

Are conscious decisions to conserve Are conscious decisions to conserve energy important?energy important?

Who is responsible?Who is responsible?

Responsible for what and to whom?Responsible for what and to whom?

Thank you

Summary