ENSP101Chapter 19 – Conventional Energy 19.1 Energy Resources and Uses- Unit of measure:o Work – the application of force through a distance; requires energy inputo Joules – a unit of energy. 1 joule is the energy expended in 1 second by a current of 1 amp flowing through a resistance of 1 ohmo Energy – the capacity to do worko Power – the rate of energy delivery; measured in horsepower or wattso Watt – the force exerted by 1 joule, or the equivalent of a current of 1 amp per second flowing through a resistance of 1 ohm- Worldwide commercial energy consumption:o Oil  37%o Coal  26%o Natural gas  24%o Nuclear  6%; Hydropower  6%; Wind etc.  1%- By 2025, energy experts expect that emerging economies, such as China and India, will be consuming nearly as much energy as Europe and North Americao India’s oil consumption has doubled sine 1992o China went from near self-sufficiency in the mid-1990s to the world’s 2nd largest importer in 2004- Oil prices have fluctuated rapidly over the past 40 years- On average, each person in the US or Canada uses more than 300 gigajoules per yearo By contrast, in the poorest countries of the world, such as Bangladesh, each person on average consumes less than one gigajoule per year- Current US energy consumption:o Imported oil  31%o Coal  22%o Gas  20%o Domestic oil  12%o Nuclear  8%o Renewables  6%- Energy use sectors:o Industrial  33.7%o Transportation  27.7%o Residential  20.6%o Commercial  18%- Fossil fuels supply 85% of the energy used in the US, and oil (3/4 of it imported) makes up half that amount- Canada is now the largest oil supplier for the US, and industry is the largest energy-use sectoro Transportation however, uses the vast bulk of all oil- About ½ of all the energy in primary fuels is lost during conversion to more useful forms, while it is being shipped to the site of end use, or during its use- Natural gas is our most efficient fossil fuelo Only 10% of its energy content is lost in shipping and processing since it moves by pipelines and usually needs very little refining19.2 Coal- Fossilized plant material preserved by burial in sediments and altered by geological forces that compact and condense it into a carbon-rich fuelo Essentially a non-renewable resource- World coal deposits are 10x greater than conventional oil and gas resources combined- Total resource is estimated to be 10 trillion metric tons- “Known reserves” have been identified but not thoroughly mapped- “Proven reserves” have been mapped, measured and shown to be economically recoverable- Ultimate reserves include unknown as well as known resources- Underground mines are subject to cave-ins, fires, accidents, and accumulation of poisonous or explosive gases (carbon monoxide, carbon dioxide, methane, hydrogensulfide)- Proven-in-place coal reserves by region:o Europe and Eurasia  36%o Asia Pacific  30%o North America  26%o Africa and Middle East  6%o South and Central America  2%- Black lung disease, inflammation and fibrosis caused by accumulation of coal dust inthe lungs or airways- Strip mining or surface mining is cheaper and safer than underground mining but often makes the land unfit for any other useo Also contributes to water pollutiono Sulfur and other water soluble minerals make mine drainage and runoff from coal piles and mine tailings acidic and highly toxico Another type of strip mining is “mountaintop removal” where the tops of mountain ridges are scraped off and dumped into valleys below to get at coalseams- Coal burning releases radioactivity and many toxic metalso You are likely to get a higher dose of radiation living next door to a coal-burning power plant than a nuclear plant under normal (non-accident) conditionso Coal combustion is responsible for about 25% of all atmospheric mercury pollution in the USo Coal-burning power plants create huge amounts of ash, most of which is pumped as a slurry into open storage pondso Coal burning is the largest single source of greenhouse gases and acid rain inmany areas- Sulfur can be removed from coal before it is burned, or sulfur compounds can be removed from the flue gas after combustiono Formation of nitrogen oxides during combustion also can be minimized- The ultimate limit to our use of coal in conventional boilers is CO2 emissions- Carbon sequestration – storing carbon in geological formations or at the bottom of the ocean- The UN estimates that at least ½ the CO2 we release every year could be pumped into deep geologic formations o This can enhance gas and oil recovery- Alternatively, CO2 can be stored in depleted oil or gas wells; forced into tight sandstone formations; injected into deep, briny aquifers; or compressed and pumped to the bottom of the ocean- Some utilities are burning coal together with biomass crops in their power plantso This produces less CO2 than coal alone, and also improves the combustion characteristics of biomass aloneo Another proposal is to convert coal to either liquid or gas19.3 Oil- Petroleum is derived from organic molecules created by living organisms millions ofyears ago and buried in sediments where high pressures and temperatures concentrated and transformed them into energy-rich compoundso Depending on its age and history, a petroleum deposit will have varying mixtures of oil, gas, and solid tarlike materials- Oil and gas deposits often accumulate under layers of shale or other impermeable sediments, especially where folding and deformation of systems create pockets that will trap upward-moving hydrocarbons- An oil pool is not usually a reservoir of liquid in an open cavern but rather individualdroplets or a thin film of liquid permeating spaces in a porous sandstone or limestone- Pumping oil out of a reservoir is much like sucking liquid out of a spongeo The first fraction comes out easily, but removing subsequent fractions requires increasing efforto Methods for squeezing more oil from a reservoir are called secondary recovery techniques- The total amount of oil in a world is estimated to be about 4 trillion barrels (600 billion metric tons), half of which is thought to be ultimately recoverableo Some 465 billion barrels of oil already have been consumed- Many geologists expect that within a decade or so world oil production will peak and then begin to decline- By far the largest supply of proven-in-place oil is in Saudi Arabia, which claims 262.7billion barrels, almost ¼