Energy is a fundamental quantity in our universe, and it cannot be created nor destroyed-only transformed. Physical laws permit us to take different types of materials in which energy is stored (like gasoline), change the state of that material (burn it to form other materials), and then harness a portion of that released energy (to power an automobile).

Yet, this elusive substance is all around us in our daily lives; it lights our cities, propels our vehicles, trains, planes and rockets. It warms our homes, cooks our food, dries and curls our hair, powers our computers, plays our music and enables television. It allows us to walk, talk and play soccer. More fundamentally, it is the engine behind all activities and motion in the entire universe. Clearly, the ability to obtain and manipulate energy to do our bidding is key to the high standard of living we enjoy today and for our future survival. This talk will present the latest information on the earth's total energy budget to see what forms of energy your generation will be harnessing.

Tapping these energy transformations through sources, however, is not without problems. The distribution of energy sources is not aligned with energy use. For example, in the U.S. an ever-increasing energy appetite maintains our standard of living yet we are only 5% of the world population using 20% of the world's energy. Can we keep that up? Can everyone on earth use that much energy? But to make matters worse the U.S.'s energy use is mainly fueled by oil and natural gas from overseas sources as U.S. production declines while most of the world's remaining hydrocarbons (reserves) are concentrated in the Middle East and Russia.

Another problem we all face is that greenhouse gas concentrations in the atmosphere, released from burning fossil fuels (mostly coal, but also oil, and gas) have increased by about a third in the last 50 years, could possibly double in the next 50 and will last for hundreds of years. Currently, scientists debate how these changes will effect the polar icecaps, ocean level, temperatures, rainfall, and weather patterns, especially the intensity and frequency of storms, but clearly we should be carefully examine the sources and the environmental effects of energy use.

To find solutions to these and other energy-related problems we first need to look at how the U.S. uses its energy. We will talk about U.S. energy flows between three general categories: sources, conversions, and we use. Each energy source has plusses and minuses so we will evaluate electricity, biomass (from plants), geothermal (from the earth), fossil fuels (coal, oil and natural gas), hydroelectric (dams), nuclear, solar, and wind energy.

Finally, we will try an answer these questions: will we run out of certain forms of energy, such as oil, and when we do, what are the replacement options? How does hydrogen, not a fuel itself, fit into the future U.S. energy picture? What is carbon sequestration and why does it matter? Energy can be stored, transformed and used to do work and there are many possibilities to consider for the future. So we will end by describing a possible future (2050) U.S. energy system utilizing both hydrogen and carbon sequestration with major shifts toward sustainable energy sources such as solar, wind and geothermal.

Student Lecture Notes

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Speaker Bios

Nalu Kaahaaina

Deputy Program Director, Energy and Environmental Security
Lawrence Livermore National Laboratory

Nalu directs research in energy technologies at LLNL, with an emphasis on large, integrated systems. This research portfolio includes renewables (wind power, geothermal), advanced conversion (combustion, fuel cells), hydrogen storage, improved vehicle aerodynamics, and energy/economics modeling.

Before joining LLNL, Nalu was the Deputy Director of the Advanced Energy Systems Laboratory at Stanford University, where he led research in novel engine design. Nalu held a concurrent appointment as Lecturer in the Mechanical Engineering Department, where he taught course in IC engines and thermal systems.

He is a member of the American Society of Mechanical Engineers and the Society of Automotive Engineers, having served the latter as a technical reviewer from 2001-04. Nalu holds B.S. (Mechanical Engineering), B.A. (Science, Technology, and Society) and M.S. (Mechanical Engineering) degrees from Stanford University.