Chapter 9

Automobile Emissions Controls

Stationary Emissions Control

Cost of Emissions Controls

Thermal Pollution from Energy Generation

Ecological Effects of Thermal Pollution

Cooling Towers

Using Waste Heat

Energy in the News

Thursday Energy Roundtable at SIPA Cancelled:

Not yet rescheduled

Automobile Emissions Controls

Emissions can be controlled in several ways

Change the fuel used by the car

Change the way that the engine burns the fuel

Decrease the use of cars by subsidizing mass transit

Changing the Fuel

What are other names for methanol, ethanol and compressed gas?

How are they made? Other drawbacks of these fuels?

The Newest Fuel: Nitrogen

Newest alternative fuel

(reported this Monday)

Works by using

decompression of

Liquid nitrogen to

Push pistons and run

The car engine.

No pollutants at all, BUT

Technology not mature.

Changing the Burning ProcessMore efficient cars emit less CO2 per mile traveled.

(In the 1970s, estimated that could run

All cars on ethanol and methanol derived from

Fermented biomass if all cars averaged 60 miles

Per gallon.)

Number is out of date, but at some gas mileage

It is possible to run all cars on renewable sources

Of hydrocarbons.

Amory Lovins: using the best technology:

Could potentially build cars

That get 150 miles per gallon.

Positive Crankcase Ventilation

At the edges of the combustion

Chamber of the engine

(above the piston tops), there is a

thin layer of gasoline that does

Not burn up. This gasoline

Constitutes an air pollutant

(what is its classification?)

To keep gasoline from returning to

The air, this gasoline is recirculated

Back into the combustion chamber.

Exhaust Gas Recirculation

Exhaust gases are

Removed from the

Crankcase and then

Recirculated back into

The carburetor.

Other Pollution Controls

Minimize CO and hydrocarbons by improving burning

Of the fuel.

To improve burning: use leaner fuels and increase

Temperatures in the combustion chamber.

Leaner fuels: means mixture of air plus fuel has more

Air and less fuel.

But leaner fuels increase Nox formation because

Burning is at higher temperatures and more oxygen is

Available to form Nox.

Catalytic converters: help to get around these problems.

They require unleaded gasoline.

Automobile Emissions Standards

Standards met by using catalytic converters, engine

Redesign and additives (MBTE, other oxidants).