Coal+Rebuttal

Jessica C- Biomass: Biomass Energy disadvantages. There really are not that many. But we do need to look at the whole picture when trying to see if biomass is a good alternative fuel to fossil fuel such as coal or oil.


 * 1. Biomass produces greenhouse emissions.** The biggest argument against biomass is that it produces carbon dioxide and other greenhouse gases.


 * 2. It takes more energy** to plant ,cultivate and harvest the crops and trees than it is worth to get a net energy gain. It also takes up more water from the earth and other fossil fuels to make the fertilizers and fuels for planting and harvesting. it also, supposedly, takes up more land for the crops and trees.


 * 3.Biomass collection is difficult.** There was a man who, in 1979, traveled from Jacksonville, Fl to Los Angeles, Ca on wood he was using in his biomass gasifier attached to a Chevy Malibu. He would travel 1 mile for every pound of wood. Not the most efficient use of fuel.

[|biomass] Tanner C- Geothermal: John M- Hydroelectricity:
 * 4. Biomass crops not available all year.** Corn, wheat, barley and the like are seasonal crops. They are not available all year. Trees are also a slow growing resource even though they are renewable. This would also tend to be a negative on the side of biomass fuels.
 * 1. ** Dams are extremely expensive to build and must be built to a very high standard.

**2.** The high cost of dam construction means that they must operate for many decades to become profitable.

**3.** The flooding of large areas of land means that the natural environment is destroyed.

**4.** People living in villages and towns that are in the valley to be flooded, must move out. This means that they lose their farms and businesses. In some countries, people are forcibly removed so that hydro-power schemes can go ahead.

**5.** The building of large dams can cause serious geological damage. For example, the building of the Hoover Dam in the USA triggered a number of earth quakes and has depressed the earth’s surface at its location.

**6.** Although modern planning and design of dams is good, in the past old dams have been known to be breached (the dam gives under the weight of water in the lake). This has led to deaths and flooding.

**7.** Dams built blocking the progress of a river in one country usually means that the water supply from the same river in the following country is out of their control. This can lead to serious problems between neighbouring countries.

**8.** Building a large dam alters the natural water table level. For example, the building of the Aswan Dam in Egypt has altered the level of the water table. This is slowly leading to damage of many of its ancient monuments as salts and destructive minerals are deposited in the stone work from ‘rising damp’ caused by the changing water table level. http://www.technologystudent.com/energy1/hydr2.htm Violet H- Oil: * Oil can be damaging to the environment because when you burn it, it releases greenhouse gases into the air. * Working on oil and gas can be dangerous because it could explode in bad weather or explosions. * Non-renewable, highly toxic. * Expensive. * Hydrogen: Austin R- Oil dis Natural Gas: Jacquelynn. R- Oil is non renewable and it takes millions of years to form. Burning oil produces carbon Dioxide, it has sulphur when burnt and that creates 'acid rain'. Oil is neither as clean nor efficient in use as natural gas, and oil is Highly Toxic.

Nick C- Nuclear: * High construction costs due to complex radiation containment systems and procedures. * High subsidies needed for construction and operation, as well as loan guarantees. * Subsidies and investment could be spent on other solutions (such as renewable energy systems). * High-known risks in an accident. * Unknown risks. * Long construction time. * Target for terrorism (as are all centralized power generation sources). * Waivers are required to limit liability of companies in the event of an accident. (This means that either no one will be responsible for physical, environmental, or health damages in the case of an accident or leakage over time from waste storage, or that the government will ultimately have to cover the cost of any damages.) * Nuclear is a centralized power source requiring large infrastructure, investment, and coordination where decentralized sources (including solar and wind) can be more efficient, less costly, and more resilient. * Uranium sources are just as finite as other fuel sources, such as coal, natural gas, etc., and are expensive to mine, refine, and transport, and produce considerable environmental waste (including greenhouse gasses) during all of these processes. * The majority of known uranium around the world lies under land controlled by tribes or indigenous peoples who don’t support it being mined from the earth. * The legacy of environmental contamination and health costs for miners and mines has been catastrophic. * Waste lasts 200 – 500 thousand years. * There are no operating long-term waste storage sites in the U.S. One is in development, but its capacity is already oversubscribed. Yucca Mountain is in danger of contaminating ground water to a large water basin, affecting millions of people. It’s difficult, if not impossible, for the U.S. to impose its will on the state of Nevada (or other places) if they don’t want to host long-term storage of waste. * There are no operating “next generation” reactors, such as high-temperature breeder reactors and particle-beam activated reactors, that are reported to produce less waste and have reduced safety concerns. Even if these technologies were ready, they wouldn’t be deployable commercially for another two decades. * Shipping nuclear waste internationally poses an increased potential threat to interception to terrorism (though this has not happened yet with any of the waste shipped by other countries). Increasing the amount of waste shipped, particularly in less secure countries, is seen as a significant increase in risk to nuclear terrorism. - http://www.triplepundit.com/2009/02/nuclear-energy-pros-and-cons/ Shawn D- Solar: Juliann A- Tidal
 * Disadvantages: **


 * Holding back the tide allows silt to build up on the river bed.
 * The dams and barrages sometimes interfere with shipping.
 * You will need to find a way to connect the electricity to the grid.
 * Pose same threats as large dams, altering the flow of saltwater in and out of estuaries, which changes the hydrology and salinity and possibly negatively affects the marine mammals that use the estuaries as their habitat
 * Turbidity decreases as a result of smaller volume of water being exchanged between the basin and the sea.
 * The average salinity inside the basin decreases, also affecting the ecosystem
 * A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed.
 * There are few suitable sites for tidal barrages.
 * Only provides power for around 10 hours each day, when the tide is actually moving in or out.
 * It only provides about 7% of the power needed for England and Wales that means that some people get their energy close to free and some pay a lot of money
 * Water is not replenished, it cannot flow away so any dirt or pollution lingers around the coast much longer
 * Needs a very big piece of sea to be cost effective
 * Cannot be used inland
 * Barrage systems require salt resistant parts and lots of maintenance
 * Affects the lives of the people who rely on fishing for a means of living
 * Limited because the tide never speeds up or slows down, and occurs on 6 hour cycles. It is also dependent on the fetch distance. The fetch is the distance the tide rises and falls, so some beaches have a very small fetch, and others have a big fetch but hardly any have a large enough fetch to support tidal energy
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Tidal energy is currently more expensive to generate than conventional energy or that from many other renewable sources.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Effects on marine life during construction phases.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Operation and control must be provided remotely and maintenance is complicated due to sea-basing of the generation facilities.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Sea-based moorings and towers to hold the generators must be placed on the sea bottom.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">The generating facilities and mooring infrastructure are potential navigational hazards.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Is only available in a small number of regions - it requires a basin or gulf that has a mean tidal amplitude of 7 meters or more. Also need semi-diurnal tides where there are two high and low tides everyday.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Even with the best barrage designs, fish mortality rate per pass through the barrage is about 15%. Solutions to this problem have either failed or are too impractical and too expensive.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Dams used in the production of tidal power can raise tide levels.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Damages like reduced flushing, winter icing and erosion can change the vegetation of the area and disrupt the balance.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Expensive to construct
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Power is often generated when there is little demand for electricity
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Barrages may block outlets to open water. Although locks can be installed, this is often a slow and expensive process.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Barrages affect fish migration and other wildlife- many fish like salmon swim up to the barrages and are killed by the spinning turbines. Fish ladders may be used to allow passage for the fish, but these are never 100% effective. Barrages may also destroy the habitat of the wildlife living near it
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Barrages may affect the tidal level - the change in tidal level may affect navigation, recreation, cause flooding of the shoreline and affect local marine life
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Causes a continual loss of mechanical energy in the Earth-Moon system (Due to pumping of water through the natural restrictions around coastlines and viscous dissipation at the seabed and in turbulence.
 * <span style="background-color: transparent; background-color: transparent; font-size: 12px; font-size: 12px;">Loss of energy has caused the rotation of the Earth to slow in the 4.5 billion years since formation losing 17% of its rotational energy.May take additional energy from the system, increasing the rate of slowing over the next millions of years.

Read more: [|http://wiki.answers.com/Q/What_are_the_advantages_and_disadvantages_of_renewable_tidal_power_as_an_energy_source#ixzz1l9toEptU]

Gage S- Wave Gage: All of that said, there are several disadvantages of wave energy that should be considered. For example, waves are not one of the most constant things in nature. Although there are always some form of waves, there is a lot of variety in how powerful those waves are throughout the year, month, and even each day. This makes it hard to estimate exactly how much electricity each wave power plant can produce each day. Another thing to consider is that many sites are not suitable for wave energy plants. Locations that have strong waves on a regular basis are the best candidates for a plant, but those types of areas are limited in number. Some of the current designs of wave power plants are relatively noisy. Experts usually don't consider this a major problem though, because the ocean's waves are fairly noisy in general so they somewhat drown out the noise created by the generator. One disadvantage of wave energy is that the upfront cost is significant. Just like most other green energy sources, the vast majority of the investment is upfront, not in the maintenance or day to day operations. Because so much money is required upfront, many organizations are hesitant to invest in wave power plants. Finally, wave energy plants can be harmful to the environment. Although they aren't as intrusive as dams or tidal energy barrages, they still make a footprint on the ecosystem where they are built. This can negatively affect marine plant life and animal life for years to come. With those major advantages and disadvantages of wave energy, it's hard to say where this industry is going. On the one hand, mankind needs to develop new technology to better harness the energy the earth has naturally given us. Wind, solar, tidal, hydro, and wave energy are a few ways to generate electricity, so they are viable options. However, the environmental and economic impacts should be considered as well, as it doesn't make sense to destroy our planet's beauty just so we can live with more electricity. Thanks for reading this article about the advantages and disadvantages of wave energy. http://www.exploregreenenergy.com/wave/advantages-and-disadvantages.php
 * Improperly placed wave power plants can damage the marine ecosystem.
 * Efficiency drops significantly in rough weather due to safety mechanisms.
 * Limited locations where waves are strong enough to produce electricity without damaging equipment.
 * Power only produced near oceans making transmission to inland customers difficult.
 * Winds (and thus waves) can be unpredictable and far from reliable. Can’t produce electricity at all times.
 * http://renewableenergyindex.com/hydro/advantages-disadvantages-wave-power

Taylor B--- The Disadvantages of Coal--

THE DISADVANTAGES OF COAL
 Burning coal emits harmful waste such as carbon dioxide, sulfuric dioxide, nitrogen oxides, sulfuric acids, arsenic and ash. It also emits twice as much carbon dioxide when compared with natural gas to produce the same level of heat, which increased the levels of harmful greenhouse gases emitted into the earth’s atmosphere. Carbon dioxide emissions from the burning of fossil fuels now account for about 65 per cent of the extra carbon dioxide in our atmosphere.  The burning of coal by large-scale factories to power industry has led to acid rain in some regions. Coal can be cleaned and/or turned into a liquid of gas but this technology has yet to be fully developed and adds to the expense of creating fuel via coal. Coal mining can scar the landscape and the equipment used for mining is large and noisy which may affect local wildlife. Transporting coal can be problematic because it requires an extensive transportation system and can also cause additional pollution in the form of emissions from transportation vehicles such as lorries, etc  There are limited stocks of coal remaining – they will be entirely depleted this millennium if we continue to burn coal in the future at the same rate we are today coal can be considered as a non-renewable energy source.The mining industry can cause health difficulties for miners and fatalities due to the potentially dangerous nature of the work. Burning dirty coal can create significant pollution problems