Energy and the Environment Exam 1 study guide

What percentage of U.S. energy (i.e., total energy consumption) was derived from various
energy resources?

Petroleum 38%, Natural Gas 36%, Nuclear power 9%, Coal 9%, Renewable Energy 9%

What are the definitions of environmental, economic, and social sustainability?

Energy systems must operate within natural systems (Ecosystems, Hydrosphere, Atmosphere), Must use resources (Commodities, Capital, Labor) responsibly to accomplish: Operational Profit, Provide continued economic activity, Ensure some level of long term growth, Must provide a good quality of life for current and future generations

What were the two major transitions in the U.S. energy economy? In what way were the economic risks minimized in those transitions?

First transitioned from wood to coal, then from coal to oil and natural gas, by adapting already active systems to new energy resources

What is the economic benefit of continuing Canadian imports of crude oil and crude-like products?

The U.S. imports primarily "heavy" oil from Canada, which is different from the "light" oil produced domestically. Cheaper to import heavy oil instead of turning light oil into heavy oil.

What are two potential economic risks of transitioning away from a fossil fuel energy system?

 Higher energy prices and disrupted supply chains —-->unstable economies & economic recessions

What is the economic “carbon bubble”?

The carbon bubble is the dependence on fossil fuels and if we don’t find renewables sources, we will eventually run out of fossil fuels and the bubble will “pop

What is the difference between measurements of power and energy amounts?

 Energy is in J, kcal,BTU, Quads etc. and power is energy over time such as Watts

What are some common units of energy? How do the units compare to each other in terms of amount of energy? Which is the smallest unit? Which is the largest?

Joule < BTU < Kilocalorie (c) < kwh (3.6x10^6J) < Twh (3.6x10^15J) < Quad BTU (1.5054x10^18J), 1 BTU = 1054 Joules  4184 Joules = 1 Kilocalorie

•        What is energy poverty?  Why is there variation in the commonly used definitions?

Simple definition for energy poverty - lack of access to fundamental energy services, such as household electricity access & clean cooking facilities within a home, Different regions focus on different aspects of energy availability

•        Which energy resource was used to generate the largest proportion of electricity in 2012? Why is that resource attractive to developing countries?

Coal, It’s abundant and cheap to mine and produce

•        Be familiar with the relationship between energy consumption rates and the human development index or sustainable development index.

o   How does the trend line change as energy consumption increases?

o   What does that mean regarding the benefits of consuming more energy?

The trend line initially increases dramatically and exponentially but then plateaus quickly. The more energy you consume the less benefits you get.

•        How do electrical, mechanical (kinetic), and thermal energy compare to each other in terms of energy quality?

Thermal is the worst quality because it is very chaotic energy then mechanical and electrical are more ordered energy 

•        How do various forms of energy compare to each other in terms of energy density?

 wood is 17 MJ/kg, Coal is 29 MJ/kg, Oil is 43 MJ/kg, Natural gas is 55 MJ/kg, Uranium is 580 GJ/kg

•        What do we consider when measuring the area term in a power density estimate?

power per area of space used (W/m^2). Typically calculated from the perspective of human land use. For mined energy resources, area = area of Earth’s surface that was mined

•        How does the efficiency of a solar photovoltaic panel affect the power density estimate? 

By affecting the actual amount of power produced per solar panel 

•        Under what conditions does peat form in a wetland? 

Area must have lots of vegetation and be wet. Water must also be low in Oxygen

What is burial diagenesis? How is it involved in the transformation from peat to coal?

Subsidence exposes biomass to other earth materials and to higher temperatures & pressures. Overall this process creates physical and chemical change over a long period of time

•        How can peat become enriched with sulfate before being converted to coal? 

Formed form environment + history of sedimentary basin (not extent of diagenesis)

What is the role of anaerobic bacteria in the formation of inorganic and organic sulfur in coal?

anaerobic bacteria breaks down sulfur dissolved in pores of peat deposits to produce sulfide ions which react with iron to produce inorganic sulfide minerals. Plant material already has naturally occurring sulfur from previous plants 

•        What kind of pollution is caused by exposure and oxidation of inorganic sulfur? 

AMD drains into watershed and Blankets the substrate & sedentary organisms, Unsuitable for attachment sites for macroinvertebrates, Decreases in photosynthetic productivity

•        What kind of pollution is caused by combustion of sulfur-bearing organics in coal?

These stay in coal and are burned at power plants, pollution in air from sulfur as well as acid rain in atmosphere

•        What are the negative impacts of this subsidence caused by longwall mining? 

Affects surface above mine such as destroying homes, flooding crops etc.

•        What are commonly used methods of reducing explosion risk in an underground coal mine?

coating mine in limestone dust, proper ventilation in mine, monitoring

•        What is the Mountain Top Removal Mining + Valley Fill technique? 

When mining on a mountain, you would take your extra rock and soil and put it into the surrounding stream valleys 

•        How does bioaccumulation of selenium affect fish species? 

Greatly affects offspring Deformity and pathological swelling at < 20 ug/g in egg tissue 100% mortality at 45 ug/g and higher

•        According to the Lindberg et al. study, how do concentrations of sulfate and selenium in stream water change as more of a watershed is altered by Mountain Top Removal techniques? 

More MTR mines = More contamination. This is true regardless of whether mine is active or not 

•        What did the Ross et al. (2016) reveal about the correlation between age/size of valley fill and selenium concentrations in watersheds?

While Curve is lower for older mines, the amount of selenium still increases with the size of of valley fills

•        Based on Elk River Basin data (Foster et al. 2024), how far can selenium be transported downstream from mines?  Why is that distance unexpected?

575 Km downstream, leads to concert hat more selenium is being introduced into the environment that previously throughout and the shows the persistent nature of selenium in aquatic environments

•        What are general differences between fly ash and bottom ash?

Fly Ash is partially molten material that is carried by flue gas & solidifies in mid-air. Solidifies as spheres inert silica (SiO2) with little to no heavy metals or NORM’s. Bottom Ash doesn’t melt and accumulates on surfaces of boiler enriched in heavy metals & NORM’s

•        What are some examples of beneficial use of coal ash? 

Encapsulated = ash wrapped/sealed in a low permeable material (concrete). Unencapsulated = not sealed (structural fill)

•        What are the oil and natural gas “windows”?  

Oil window is between 3-6 km in depth temps need to be 90-150 C, Natural Gas window is between (6-9 km) in depth 150- 225 C 

•        What are the four main components of a conventional hydrocarbon system? 

Thermally mature source rock rich in organics (low permeability & low porosity). Migration pathway = natural conduit through which the fluids leave source rock. Reservoir rock (high porosity and high permeability). Trap & seal geometry —> concentrate & further prevent movement to the surface.

•        What is the purpose of installing cement and steel casing into a borehole? 

Casings and cement are necessary to prevent collapse of the bore hole and hydrocarbons from escaping in upper layers of rock or in aquifers.

•        What are typical fluids that may leak upwards through a well? What are their sources?

1.Methane-rich, low permeability rock layers (e.g., coal seams) 2. Fluid-rich, high permeability rock layers (e.g., sandstones containing “formation water”) 3. Biogenic or thermogenic methane in shallow aquifers (i.e., produced by decomposition) 4. Hydrocarbons from the reservoir rock (i.e., from the production layer)

•        How can well failure (i.e., loss of well integrity) be determined from a pressure integrity test?

By pressurizing the tubes and seeing if there is any changes in the rate of pressurization of failure to reach leak-off point