EnergyEnergy

The ultimate addiction of civilisationThe ultimate addiction of civilisation

Energy consumptionEnergy consumption

90% of energy consumed in developed 90% of energy consumed in developed countries is from fossil fuelscountries is from fossil fuels

10% are from hydropower, nuclear, solar, 10% are from hydropower, nuclear, solar, windwind

Renewable sources are Renewable sources are alternative sourcesalternative sources

Energy efficiency: 1Energy efficiency: 1stst law law

First law efficiencyFirst law efficiency – amount of E without – amount of E without consideration of its quality. Expressed as a %. consideration of its quality. Expressed as a %.

It is a ratio of the actual amount of energy It is a ratio of the actual amount of energy delivered where it is needed to the amount of delivered where it is needed to the amount of energy supplied to meet that needenergy supplied to meet that need

A fluorescent bulb converts 1/5 of electrical A fluorescent bulb converts 1/5 of electrical energy into light. Thus its 1energy into light. Thus its 1stst law efficiency is law efficiency is 20%20%

Energy efficiency: 2Energy efficiency: 2ndnd law law

Second law efficiencySecond law efficiency: the ratio of : the ratio of minimum available work needed to minimum available work needed to perform a particular task to the actual perform a particular task to the actual work needed to perform that taskwork needed to perform that task

A car has a 1A car has a 1stst law efficiency of 20%. law efficiency of 20%. 80% is unusable energy.80% is unusable energy.

Out of that 20% 1Out of that 20% 1stst law efficiency, 10% is law efficiency, 10% is 22ndnd law efficiency law efficiency

Energy efficiencyEnergy efficiency

11stst law efficiency may be misleading. A high law efficiency may be misleading. A high efficiency may mean no more energy saving efficiency may mean no more energy saving improvements may be done.improvements may be done.

22ndnd law efficiency takes note of work. That is law efficiency takes note of work. That is energy applied.energy applied.

A car has a low 2A car has a low 2ndnd law efficiency since high law efficiency since high quality gasoline wastes much heat that quality gasoline wastes much heat that otherwise may used to do additional work.otherwise may used to do additional work.

The solution is to use a fuel that doesn’t waste The solution is to use a fuel that doesn’t waste much heat and do more useful work.much heat and do more useful work.

REGULAR COMBUSTION REGULAR COMBUSTION ENGINEENGINE

A lot of the energy is wasted in the heat A lot of the energy is wasted in the heat of the exhaust as well as in the radiator.of the exhaust as well as in the radiator.

Pollution (NOPollution (NOxx , SO , SOxx VOC and other) VOC and other)

Has a very low efficiency, about Has a very low efficiency, about

20-25% .*20-25% .*

* Physics Today. April 2002

What is energy What is energy conservation?conservation?

This refers simply to This refers simply to getting by with more getting by with more work with less demandwork with less demand for energy for energy

This means improving 2This means improving 2ndnd law efficiency law efficiency Cogeneration: using waste heat to do Cogeneration: using waste heat to do

supplementary worksupplementary work Example: Have you heard of the guy who Example: Have you heard of the guy who

barbecues while drivingbarbecues while driving his V8 engine car? his V8 engine car?

Fossil fuelsFossil fuels

95% of Philippine energy needs95% of Philippine energy needs Relatively cheap as of now.Relatively cheap as of now. Petroleum is also made into plastics and other Petroleum is also made into plastics and other

synthetic materials including fertilizerssynthetic materials including fertilizers Only a few countries have enough supplies. Only a few countries have enough supplies.

E.g. Saudi Arabia, IraqE.g. Saudi Arabia, Iraq Some of the countries have political problemsSome of the countries have political problems

Where is the oil?Where is the oil?

Why is the price of oil Why is the price of oil going up?going up?

Economic developmentEconomic development China, India and Southeast Asian China, India and Southeast Asian

countries have a rising middle class who countries have a rising middle class who want carswant cars

Political troubles: Iraq, Saudi ArabiaPolitical troubles: Iraq, Saudi Arabia USA- preference for SUVsUSA- preference for SUVs New oilfields require more investmentsNew oilfields require more investments

Top 5 consumers of oilTop 5 consumers of oil

1.1. United StatesUnited States

2.2. ChinaChina

3.3. RussiaRussia

4.4. JapanJapan

5.5. United States’ AutomobilesUnited States’ Automobiles

Two major choicesTwo major choices

Change your car for Change your car for cars with new cars with new propulsion technologiespropulsion technologies (hybrids, fuel (hybrids, fuel cells or electric)cells or electric)

Change from gasoline or diesel to new Change from gasoline or diesel to new fuels but these fuels but these new fuels can run your new fuels can run your car without engine modification (car without engine modification (biodieselbiodiesel))..

Easier to Change the Car Easier to Change the Car Than to Change the Than to Change the Person!!Person!!

Sport Utility Vehicles are a Status SymbolSport Utility Vehicles are a Status Symbol Only 10-30% of people who own SUVs actually use Only 10-30% of people who own SUVs actually use

them for off-road activitiesthem for off-road activities 38% of the cars on the road are SUVs38% of the cars on the road are SUVs

With Hybrid technology, people can keep their With Hybrid technology, people can keep their “big” cars while using less fuel.“big” cars while using less fuel. Ford Escape, 2004Ford Escape, 2004 Dodge Durango SUV, uncertain release dateDodge Durango SUV, uncertain release date

How Hybrids WorkHow Hybrids Work

Electric portion of the motor gets power Electric portion of the motor gets power from nickel-metal hydride battery (next to from nickel-metal hydride battery (next to fuel tank)fuel tank)

NO PLUGGING IN NEEDED! (battery NO PLUGGING IN NEEDED! (battery maintained by regenerative braking- maintained by regenerative braking- kinetic energy captured by forward kinetic energy captured by forward momentum)momentum)

Gasoline engine made from plastic Gasoline engine made from plastic materialsmaterials

Other car technologiesOther car technologies

Electric carsElectric cars Hybrid cars- gas and electricHybrid cars- gas and electric Fuel cell cars Fuel cell cars

Why go alternative?Why go alternative?

Mileage- a hybrid car can go 20 km or Mileage- a hybrid car can go 20 km or more to a litermore to a liter

More environment friendlyMore environment friendly Celebrity appeal: Leo DiCaprio drives 4 Celebrity appeal: Leo DiCaprio drives 4

hybrid cars. Russel Crowe drives one.hybrid cars. Russel Crowe drives one.

How It Works How It Works

Two or more sources of power combinedTwo or more sources of power combined Ex:Ex:

Mo-pedMo-ped TrainsTrains BusesBuses Mining trucksMining trucks Submarines Submarines

A BATTERY-POWERED A BATTERY-POWERED CARCAR

Battery efficiency: ~90%Battery efficiency: ~90%Motor efficiency ~80%Motor efficiency ~80%TOTAL: TOTAL: 72%72%No Pollution No Pollution ??????Remember that the power had to be Remember that the power had to be

generated somewhere else, most likely a generated somewhere else, most likely a conventional coal plant! ~40%.conventional coal plant! ~40%.**

Real Efficiency ~29%Real Efficiency ~29%

* Berinstein, Paula. Alternative Energy: Facts, Statistics, and Issues. Westport, CT, Oryxpress 2001

Comparing the Battery and Comparing the Battery and Fuel Cell in automobileFuel Cell in automobile

Fuel cell slightly more efficient and Fuel cell slightly more efficient and without the conventional pollutionwithout the conventional pollution

Fuel cell design offers convenient Fuel cell design offers convenient “recharge” at a gas station“recharge” at a gas station

Fuel cell automobiles are still much more Fuel cell automobiles are still much more expensive ($80,000expensive ($80,000

80mpg/52mpg (Toyota Prius-hybrid)80mpg/52mpg (Toyota Prius-hybrid)

~300

~0

~0

~0

~6-7,000

Can perform similar analysis for a large scale power generation

ComponentsComponents

Gas engineGas engine Fuel tankFuel tank Electric motorElectric motor GeneratorGenerator BatteriesBatteries Transmission Transmission

Electric Motor Electric Motor ComponentsComponents

Armature or rotorArmature or rotor Thin wire coiled around two or more polesThin wire coiled around two or more poles

CommutatorCommutator Plate pair attached to axlePlate pair attached to axle

BrushesBrushes Provides “flipping” action with the commutator Provides “flipping” action with the commutator

AxleAxle Field magnetField magnet DC power supplyDC power supply

PolesPoles

Car motors usually have 3 poles…Car motors usually have 3 poles… Better dynamics in the car (magnet cannot Better dynamics in the car (magnet cannot

get “stuck” b/w the poles)get “stuck” b/w the poles) Avoids wasting energy and wasting the Avoids wasting energy and wasting the

batterybattery

GeneratorGenerator

Similar to electric motor, but only Similar to electric motor, but only produces electrical powerproduces electrical power

Used in series hybridsUsed in series hybrids Electric motor acts like a generator when Electric motor acts like a generator when

it slows car down to charge the batteriesit slows car down to charge the batteries

Batteries Batteries

Higher voltagesHigher voltages serial serial Higher currentsHigher currents parallel parallel Energy storage device for electric motorEnergy storage device for electric motor Electric motor: puts energy into batteries Electric motor: puts energy into batteries

and draws from themand draws from them Gives that extra “help”Gives that extra “help”

The upper arrangement is called a parallel arrangement. If you assume that each cell produces 1.5 volts, then four batteries in parallel will also produce 1.5 volts, but the current supplied will be four times that of a single cell. The lower arrangement is called a serial arrangement. The four voltages add together to produce 6 volts.

Types of HybridsTypes of Hybrids

Parallel hybridParallel hybrid Fuel tank provides gasoline to engineFuel tank provides gasoline to engine Batteries supply power to electric motorBatteries supply power to electric motor Engine and electric motor work together to Engine and electric motor work together to

turn transmission simultaneouslyturn transmission simultaneously Transmission turns the wheelsTransmission turns the wheels

Parallel HybridParallel Hybrid

Fuel tank and gas engine connect to Fuel tank and gas engine connect to transmissiontransmission

Batteries and electric motor connect to Batteries and electric motor connect to transmission independently transmission independently

Thus, electric motor and gas engine Thus, electric motor and gas engine propel autopropel auto

Civic Hybrid StatsCivic Hybrid Stats

48 mpg city/47 mpg highway (ULEV)48 mpg city/47 mpg highway (ULEV) Actual: 43 mpg city / 52 mpg highway Actual: 43 mpg city / 52 mpg highway City fuel efficiency decreases in winter when temps City fuel efficiency decreases in winter when temps

are below freezing; closer to 35 mpg in city; highway are below freezing; closer to 35 mpg in city; highway stays the samestays the same

47 mpg city/48 mpg highway (SULEV)47 mpg city/48 mpg highway (SULEV) 1/03: SULEV marketed in California1/03: SULEV marketed in California

650 miles per tank of gasoline650 miles per tank of gasoline IMA technology; 1.3 L VTEC 4-cylinder engineIMA technology; 1.3 L VTEC 4-cylinder engine 10 year battery life10 year battery life

Toyota PriusToyota Prius

Parallel hybridParallel hybrid Electric motor starts the carElectric motor starts the car Power Split DevicePower Split Device

Series hybridSeries hybrid

Only Available in a Continuously Variable Only Available in a Continuously Variable Transmission (CVT)Transmission (CVT)

How to make the most of How to make the most of your hybridyour hybrid

Don’t speedDon’t speed Keep speed constantKeep speed constant Don’t stop abruptlyDon’t stop abruptly Manual transmissions: let the Manual transmissions: let the

regenerative braking work before putting regenerative braking work before putting in the clutchin the clutch

WHAT IS A FUEL CELLWHAT IS A FUEL CELL

Reversed Electrolysis Reversed Electrolysis DeviceDevice

Pt coated electrodesPt coated electrodes

Use air as a source of Use air as a source of OO22

How Does it WorkHow Does it Work

Electrolyte- proton-Electrolyte- proton-exchange-membrane exchange-membrane (PEM), Phosphoric Acid(PEM), Phosphoric Acid

Combines Fuel and Combines Fuel and OxygenOxygen

Produces HProduces H220 (l), heat, 0 (l), heat, COCO22

www.howstuffworks.com

Still a little fuzzy? DOE’s website:http://fossil.energy.gov/coal_power/fuelcells/fuelcells_howitworks.shtml

ADVANTAGES OF FUEL ADVANTAGES OF FUEL CELLSCELLS EFFICIENCYEFFICIENCY

Fuel cells can convert as much as 80% of the Fuel cells can convert as much as 80% of the energy stored in the fuel energy stored in the fuel **

QUIETQUIET

NO MOVING PARTSNO MOVING PARTS

EXTRA HEAT CAN BE USEDEXTRA HEAT CAN BE USED

* Berinstein, Paula. Alternative Energy: Facts, Statistics, and Issues. Westport, CT, Oryxpress 2001

Graph Courtesy of Mercedes-Benz

MORE ADVANTAGESMORE ADVANTAGES

Low Pollution- Fuel cells produce only Low Pollution- Fuel cells produce only water and COwater and CO22 depending upon the fuel depending upon the fuel usedused

Low Maintenance/Operating costLow Maintenance/Operating cost

Can use conventional fuels - gasoline, Can use conventional fuels - gasoline, methane, propanemethane, propane

Small or large scale usesSmall or large scale uses

DISADVANTAGESDISADVANTAGES

Still produce COStill produce CO22 although with more although with more usable energy.usable energy.

Expensive: (Pt) It costs about $40,000 to Expensive: (Pt) It costs about $40,000 to make a fuel cell system for a car.make a fuel cell system for a car.** (Power plant estimated costs 1999: $800-1200/kWh (The first one in (Power plant estimated costs 1999: $800-1200/kWh (The first one in

Austin cost about $4000/kW)Austin cost about $4000/kW)****))

Hydrogen/Reformer ProblemHydrogen/Reformer ProblemClean FuelClean Fuel

* Berinstein, Paula. Alternative Energy: Facts, Statistics, and Issues. Westport, CT, Oryxpress 2001** Daily Texan 17.7. 2002

FUEL CELL IN FUEL CELL IN AUTOMOBILESAUTOMOBILES

Fuel Cell efficiency~40% (depends on fuel)-Fuel Cell efficiency~40% (depends on fuel)-recall reformer, up to 80% if heat regeneratedrecall reformer, up to 80% if heat regenerated

Motor efficiency ~80%Motor efficiency ~80%

Can be combined with recharging while brakingCan be combined with recharging while braking

Overall Efficiency: ~32%Overall Efficiency: ~32%

What about other What about other alternatives?alternatives?

Solar energy- perfect for heating but has Solar energy- perfect for heating but has low 1low 1stst law efficiency (electricity) law efficiency (electricity)

Biofuels –low efficiency: renewableBiofuels –low efficiency: renewable Nuclear – efficient but has waste disposal Nuclear – efficient but has waste disposal

problemproblem Garbage – low efficiencyGarbage – low efficiency

The major disadvantage The major disadvantage of alternativesof alternatives

EXPENSIVE!!! A hybrid car is double or EXPENSIVE!!! A hybrid car is double or triple the price of a standard cartriple the price of a standard car

That’s why only the likes of Russel That’s why only the likes of Russel Crowe and Leo Dicaprio can afford one!Crowe and Leo Dicaprio can afford one!

However some alternatives are cheapHowever some alternatives are cheap.. A pair of walking shoes is much cheaper A pair of walking shoes is much cheaper

than an SUV.than an SUV. And so is a bicycle!And so is a bicycle!

How can we conserve How can we conserve energy?energy?

Increase your 2Increase your 2ndnd law efficiency: walk (walking law efficiency: walk (walking is good for the heart!)is good for the heart!)

Properly maintain your carProperly maintain your car Take public transport. This increases 2Take public transport. This increases 2ndnd law law

efficiencyefficiency Turn off the lights when not in use. Use natural Turn off the lights when not in use. Use natural

lightinglighting Use airconditioning when absolutely needed.Use airconditioning when absolutely needed.

What kind of energy What kind of energy efficiency are you efficiency are you improving?improving?

I jog to my next class in Palma Hall.I jog to my next class in Palma Hall. I car poolI car pool Instead of taking Ikot or Toki, I bike to my Instead of taking Ikot or Toki, I bike to my

next classnext class I use low wattage fluorescent bulbsI use low wattage fluorescent bulbs I use a solar powered calculatorI use a solar powered calculator

More on alternative More on alternative energy sourcesenergy sources

Alternative energyAlternative energy BiodieselBiodiesel