Drossman/Veirs EV112 Block 5, 2002

ENERGY

The goal of this course, EV112, "Energy" is to introduce you to the physics and chemistry of energy within the context of society's use of energy. Over the past two centuries, humans have greatly increased their numbers and have created technologies that require the use of more and more energy. The Earth's capacity for providing such quantities of energy and accepting the pollution and waste from using this energy is being severely stressed.

Almost all of the energy that society uses can be traced back to our Sun. The energy in the chemical bonds in our food was created from sunlight by photosynthesis. The energy in a car's gas tank is in chemical bonds that store solar energy captured millions of years ago. Hence, we begin in the Sun and explore the dance between gravitational attraction and electrical repulsion and nuclear forces in the very center of our Sun. Energy released by fusion here flows outward and becomes electromagnetic radiation that enters Earth's atmosphere where it warms our planet and provides the energy for plants to grow. We will follow this energy using physical laws that give us a quantitative understanding of flows and conversions. We will examine how we have used such energy in the past and quantify how much each of us uses today. Further, we will study the reactions that convert the energy in fuel into useful work. We will end the first week with a project to quantify your personal 'ecological footprint'.

Throughout the second week we will return to these themes of energy conversion and apply two of the most fundamental intellectual discoveries of all time. The "First Law of Thermodynamics" simply stated says that while energy can change its form it can't lose its value. This statement is so simple but its ramifications loom very large and its applications stretch the mind and imagination. The "Second Law of Thermodynamics" tells us that processes that convert heat into work cannot be perfect and the limitations that are expressed via the Second Law constrain society's thirst for energy and stress our Earth's capacity. We will study these two laws in many contexts applying them to heat engines and electric generators. We will end the second week with a project to quantify the 'ecological footprint' of the CC campus.

In the third week we will first study the types of pollutants that result from energy conversion to answer questions like: why do we have acid rain downwind of fossil fuel burning power plants? Next, we will use the concept of enthalpy to determine how different fuels compare in running our industrial systems. We will then determine how entropy and enthalpy determine the Gibbs energy for a reaction or process. Gibbs energy provides a link to expressions for chemical equilibrium that allow us to quantify the unwanted and the unintended consequences of energy conversion, such as why carbon monoxide and nitrogen oxides come out of tailpipes and fossil fuel power plants. We will then explore concepts of chemical kinetics to determine what 'bad ozone' is and where it comes from? Last, we will ask the question of whether nuclear power can solve these problems safely?

During the last week of the course we will study a new technology that is just emerging as a practical energy conversion device. Fuel cells convert hydrogen into water and use the energy for the generation of heat and electricity. We will study the electrochemistry of fuel cells and batteries to see if these devices might ease some of the environmental tensions that threaten the stability of our world.