Chapter 20: Conventional Energy Alternatives

Term
1 / 41
Chernobyl
Click the card to flip 👆
Terms in this set (41)
Chernobyl
nuclear power plant in Ukraine/ accident sent fallout through the atmosphere to Sweden, confirming this decision for many.
what are the new sources promoted?
wind power, solar power, hydropower, and bioenergy
where does more than 80% of our energy come from?
comes from oil, coal, and natural gas
what are considered conventional alternatives to fossil fuels? why?
nuclear power, biomass (bioenergy) and hydropower because they are already well-established and in wide use
how is the impact for conventional alternatives?
less impactful than "new renewable" alternatives like solar, wind, geothermal, and ocean power.
nuclear power
the use of nuclear energy to generate electricity
nuclear energy
the energy that holds together protons and neutrons in the nucleus of an atom
nuclear reactors
facilities contained within nuclear power plats where thermal energy is used to generate electricity
nuclear fission
the spitting apart of atomic nuclei
moderator
inside nuclear reactors, this substance (usually water or graphite) will slow down neutrons emitted by fission enough that they will impact other atoms, creating a fission chain reaction.
control rodsmade of neutron-absorbing substance can be inserted or removed from the reactor to control the rate of the reactionhalf-lifethe amount of time it takes for half of the atoms to give off radiation and decaywhat are the drawbacks of radioactive waste?disposing it and the potential for an accident at the plantnuclear fusionforces together the small nuclei of lightweight elements under extremely high temperature and pressureThree Mile Island accidentwas due to human error and mechanical failure that led to draining of water from the reactor vesselmeltdownwhen the fuel rods melted and began releasing high amounts of radiation (cooling isn't happening)Fukushima Daiichinuclear power plant, the earthquake shut down power, and the tsunami flooded its backup generators that powered the control rods and water pumps.what is another concern of radioactive material?that it could be stolen from plants and used in terrorist attackswhere is nuclear waste from power generation being stored?in pools of cooling ponds or thick casks of steel, lead and concretebioenergythe energy derived from biomassbiomassconsists of organic material derived from living or recently living organisms, and it contains chemical energy that originated with sunlight and photosynthesisis bioenergy renewable?yes and releases no net carbon dioxide into the atmospherewhere do we harness bioenergy from?from many types of plant matter, including wood from trees, charcoal, and crop residue, as well as from combustible animal waste.biopowergenerating heat and electricity from sources of bioenergybiogasanother course of biopower from the anaerobic bacterial breakdown of waste in landfills, which produces methane that can be captured and sold as fuel.co-firingwhen biomass can be combusted directly to generate electricity, or mixed with coal.benefits of biopower?it is cleaner, contributes less to climate change, and is generally more sustainable than burning fossil fuelsethanolproduced by fermenting biomass, generally fro carbohydrate-rich cropswhy is ethanol not our most sustainable energy choice?growing corn to make ethanol intensifies pesticide use, fertilizer use, freshwater depletion, energy use, and other impacts of industrialized agriculture. Also, a significant amount of land is neededbiodiesela fuel produced from vegetable oil, used cooking grease, or animal fatwhat are some of the advantages of biodiesel?less vehicle emissions, nearly identical fuel economy, cost effective, nontoxic and biodegradable, can be sources from food waste.cellulosic ethanol(nondigestible part of the plant) used by researches by using enzymes to produce ethanol from cellulose.is bioenergy carbon-neutral?yes, because it release no net carbon into the atmospherehydroelectric power (hydrpower)uses the kinetic energy of flowing river water to turn turbines and generate electricitystorage techniqueinvolves storing and releasing water through a series of turbines in a damrun-of-rivertechnique diverts a portion of the river's flow through a pipe or channel, passing it through a powerhouse, and returning it to the river. doesn't generate as much power, though.what is the amount of electricity generated by hydropower pants dependent on?the volume of water and the distance that it fallspumped storagehydropower works by transporting water from a lower reservoir to a higher reservoir during times when demand for power is weak and prices are lowwhat are the three advantages of hydropower over fossil fuels?1. renewable source of energy 2. hydropower is efficient 3. no carbon dioxide or other pollutants are emittedwhat are some negative impacts of hydropower on streams?-if flood upstream, deprives of water downstream of the dam -dams cause thermal pollution if the river downstream is kept artifical shallow and it warms rapidly in the sun -thermal shocks can occur if cold water is suddenly released from the dam's reservoir -the passage of fish and other organisms through the river is blockedwhy does hydropower have less room for expansion than other alternative energy sources?because most of the world's large rivers have already been dammed