NaimExplain

Policy issues and goals for alternative renewable energy ? Answer: Encouraging and funding alternative energy research and development. Ensuring fair access to alternative energy sources. Developing a fiscal framework that takes into account the external costs of fossil fuels and the benefits of alternative energy sources. Developing planning initiatives that promote environmentally preferred and socially acceptable alternative energy. Establishing industrial training programs to retrain workers in alternative energy industries (rural agricultural regions and former coal mining communities). Encouraging funding institutions to support community investment in alternative energy.

Difference between geothermal electric and ground source heat pumps ? Answer: Geothermal systems use heat directly from natural sources like hot springs, geysers and volcanic hot spots like the installation on the right in Iceland. Ground source heat pumps are air conditioners that use groundwater or simply soil to cool the condenser instead of an outside coil and fan. It uses electricity to move heat energy from one place to the other. Run it backwards and it provides heat, more efficiently than using the electricity directly.

What are the advantages and disadvantages of geothermal energy? Advantages of geothermal energy : Environmental impact is not as extensive as that of other sources of energy.Production of geothermal energy only released about 12% of carbon dioxide and sulfur dioxide released from burning coal to produce a given amount of electricity. Development of geothermal energy does not require large-scale transportation of raw materials or refining of chemicals as development of fossil fuels does. Does not produce the atmospheric pollutants associated with burning fossil fuels or the radioactive waste associated with nuclear energy. Disadvantages of geothermal energy : On site noise, emissions of gas, disturbance of the land at drilling sites, disposal sites, roads and pipelines, and power plants. Produces considerable thermal pollution from hot wastewaters which may be saline or highly corrosive. Degradation of tropical forests as developers construct roads, build facilities, and d...

Why is geothermal energy source limited for use? Answer: May be considered a nonrenewable energy source when rates of extraction are greater than rates of natural replenishment. Origin in the natural heat production within earth

What is geothermal energy? How can electricity be generated using geothermal energy? Geothermal energy is natural heat from the interior of the Earth that is converted to heat buildings and generate electricity. Used in 21 countries; total worldwide production is about 9,000 MW; supplies less than 0.15% of the total energy supply In some areas, heat flow is sufficiently high to be useful for producing energy. for the most part, areas with high heat flow are associated with plate tectonic boundaries. Oceanic ridge systems (divergent plate boundaries) and areas where mountains are being uplifted and volcanic island arcs are forming (convergent plate boundaries) are areas where this natural heat flow is anomalously high -> ex: Western U.S. Several types of hot geothermal systems (more than 80 degrees celsius) are said to be resource bases larger than that of fossil fuels and nuclear energy combined. Lower temperature geothermal sources that cannot be used to produce electric...

What are the advantages and disadvantages of using biodiesel? Advantages of using biodiesel : Renewable energy source. Less polluting than petroleum diesel. Lack of sulfur extends the life of catalytic converters. Cleaner fuels and keep the engine running longer. Brings down overall pollution check costs. Can be blended with other energy resources and oil. Lower carbon emissions and less greenhouse gases. Disadvantages of using biodiesel : 1.5x more expensive than petroleum diesel fuel. A lot of energy required for sowing, fertilizing, harvesting and producing fuel from soy crops. Dirt can clog the fuel filter. Can't be transported in pipelines, increases the cost. Not suitable in low temperatures. Forms into gel or crystals which block fuel lines in a vehicle.

What are the advantages and disadvantages of using ethanol? Advantages of using ethanol : Wastes are now treated to produce biogas and liquid fertilizers recycled to sugarcane fields In Hawaii, sugarcane waste is burned to produce electricity There is now sufficient idle farmland to produce enough ethanol to meet fuel needs for most of the U.S. vehicles; however, this is not practical for economic reasons and automobile engines would need modifications to run smoothly on pure ethanol. Disadvantages of using ethanol :  The wastes from ethanol distillation were originally dumped in rivers, causing water pollution.

What is the difference between ethanol and biodiesel? Ethanol: Energy crops such as sugarcane are grown to be fermented to produce ethanol, a fuel that can be used in automobiles  Brazil produces about 12 billion liters of ethanol per year which equals 60% of the fuel used for the nation's cars or about 15% of the total use of petroleum Example - alcohol produced by corn, potato, sugar, wheat, etc.  Biodiesel: Renewable, and clean burning energy source Made from a mix of feedstocks. Recycled cooking oil, soybean oil, and animal fats. (and algae) It can be used in only diesel engines without modifications Biodiesel reduces greenhouse gas emissions by at least 57 percent and up to 86 percent compared to petroleum diesel. Reduces lot of pollution from big trucks which use petroleum diesel.

What is biomass energy? Answer: Biofuel is energy recovered from -biomass - organic matter such as plant material and animal waste. The energy from biomass comes from chemical bonds formed through photosynthesis in living or once living matter. Biomass fuel is organic matter that can be burned directly or converted to a more convenient form and then burned (oldest) Biomass continued to be a major source of energy in human beings throughout the history of civilizations in North America. Forests were cleared for agriculture by girdling trees and the wood was used as fuel. More than 1 billion people still use wood as their primary source of energy for heat and cooking. In developing countries, biomass provides about 35% of the total energy supply. Energy from biomass can take several routes: direct burning of biomass either to produce electricity or to heat water and air; heating of biomass to form a gaseous fuel (gasification); and distillation or processing of biomass to...

What are the advantages and disadvantages of wind power? Disadvantage of wind power: The cost of producing electricity from wind must be competitive with other sources to be economically viable -> now it costs less than electricity from natural gas. Large windmill farms use large areas of land for roads, pads for windmills, and other equipment. Windmills may degrade an area's scenic resources. Advantage of wind power:  Large energy potentially, turbine designs have improved drastically, and cost is competitive with fossil fuels (meaning low cost). Advantage of areas such as coastal region of the northeastern U.S. and a belt extending from northern Texas through the Rocky Mountain states and the Dakotas, and winds in the Pacific Northwest coastal area. Serves as an alternative energy source that will help reduce dependence on fossil fuel and help achieve sustainability. Wind energy is growing at about 30% per year It is believed that there is enough ewin e...

What limits the use of wind power? Wind tends to be highly variable in time, place, and intensity. Even in a particular area, the direction, velocity, and duration of wind may be quite variable depending on local topography and temperature differences in the atmosphere (geographic, meteorological problem) wind velocity increases over hilltops (vertical convergence) and wind may be funneled through a mountain pass (horizontal convergence). Need instruments that measure and monitor over time the strength, direction, and duration of the wind. Small windmills generate only 1 Kw of power which is too small to be considered for central power generation needs. California wind farms produce about 1.5% of the state's electricity. Total installed world wind power is 48,000 MW which is 48 times those of nuclear power plant

What is wind power? Answer: Wind power, like solar power, has evolved over a long period of time, from early chinese and Persian civilizations to the present. Used to propel ships, drive windmills, grind grain, pump water, generate electricity, etc. Winds are produced when differential heating of Earth's surface creates air masses with differing heat contents and densities. Wind power is when wind spins turbines to create energy. Wind power can be inconsistent and will not work in some areas that are wooded, or do not get lots of wind.

What is tidal power? Tidal power is a type of water power derived from ocean tides and can be traced back to tenth century britain, where tides were used to power coastal mills. Cannot be used in many areas because tides have to be within the minimum range of about 8m. To harness tidal power, a dam is built across the entrance to a bay or estuary, creating a reservoir. When there is sufficient water to run the turbines, the dam is opened, and water flow through it into the reservoir, turning the blades of the turbines and generating electricity - ebb tide (tide falling), flood tide (tide rising) - the first and largest modern tidal power plant is the La Rance tidal power plants in north coast france - Produces about 240,000 kW from 24 power units spread out across the dam Environmental effects: - change in the hydrology of a bay or estuary caused by the dam can adversely affect the vegetation and wildlife. - dam restricts upstream and downstream passage of fish. - the ...

What are the advantages and disadvantages of using hydroelectric energy? - Hydropower can be used to generate either electrical power or mechanical power to run machinery; its use may help reduce the high cost of importing energy - Can help small operations become more independent of local utility providers. - Water power is clean power; it requires no burning of fuel, does not pollute the atmosphere, produces no radioactive or other waste, and is efficient. Environmental prices to pay ( Disadvantages of using hydroelectric energy) : Large dams and reservoirs flood large tracts of land that could have had other uses - towns and agricultural lands may be lost. Dams block the migration of some fish. Dams trap sediment that would otherwise reach the sea and eventually replenish the sand on the beaches. Many people do not want to turn wild rivers into a series of lakes. Reservoirs with large surface areas increase evaporation of water compared to pre-dam conditions. In...

What is hydroelectricity? How much of the US electric supply is generated by hydroelectric power plants? Answer: Water power is a form of stored solar energy, because climate, which dictates the flow of water on Earth, is driven in part by differential solar heating of the atmosphere. Today, hydroelectric power plants use the water stored behind dams. In the U.S., hydroelectric plants generate about 80,000 MW of electricity - about 10% of the total electricity produced in the nation like in Norway and Canada, hydroelectric power plants produce most of the electricity used. Hydropower can also be used to store energy through the process of pump storage. During times when demand for power is low, electricity produced from oil, coal, or nuclear plants in excess of the demand is used o pump water uphill to a higher reservoir. Then, during times when demand is high, the stored water flows back down to a low pool through generators to help provide energy. Micro-hydropower syst...

What are the major advantages of using hydrogen as an energy source? - High quality, and can be used like fossil fuels, and fuel cells (similar to batteries in that electrons flow between negative and positive poles, but fuel cell generates electricity rather than just storing it as in a battery) use hydrogen to produce electricity. - The advantages are that when it is burned, it produces water and no SOX or CO2 is released. It can also be transported in pipelines and stored in tanks; and it can be produced using solar and other renewable resources. Also, since it can store energy, it can be used with other types of alternative energies, and on days when there is no sun or wind, hydrogen can be used to produce electricity. - The disadvantage is that hydrogen gas must be produced. It is not widely used because it is an unstable form of energy. Also one way to produce hydrogen is to use an electrical current to separate hydrogen from water through electrolysis. This way to prod...

Where in the US is solar energy potential the greatest? Answer: - The midwest due to the high amount of sun and open area. - Luz solar electric-generating system (Mojave desert) - nine solar farms comprises a power plant surrounded by solar collections. The system uses these solar collectors to heat a synthetic oil that flows through heat exchangers, which drive a steam turbine generator. An advantage to this system is that it is modular, which allows for individual solar farms to be constructed relatively quickly. It is a success because it uses a natural gas burner backup system for cloudy days and during times of peak demand. Therefore, it is a combination of solar technology and conventional power generation.

What is solar thermal electric generation? Briefly describe how it works. Disadvantages of using solar energy Answer: The system works by collecting heat from solar energy and delivering this energy in the form of steam to turbines that produce electric power. How it works : An experimental 10-MW power tower near Barstow, California, is surrounded by mirror modules with reflective areas. The mirrors adjust continually to reflect as much sunlight into the tower as possible. This system was also capable of storing the energy in a molten salt heat-storage system Disadvantages of using solar energy:  It is relatively dispersed, arriving at Earth's surface like a fine mist, so that a large land area is required to generate a large amount of energy. Highly centralized and high-technology solar energy units, such as solar power towers, have a greater impact on the land because they need more space. Concern in the involvement of the large variety of metals, glass, p...

What are photovoltaics (PV)? What are the environmental costs and benefits of photovoltaic systems? - Photovoltaics is a technology that converts sunlight directly into electricity. Photovoltaics are the world's fastest growing source of energy, with a growth rate of about 35% per year. - Electricity is produced when sunlight strikes the cell. The different electronic properties of the layers cause electrons to flow out of the cell through electrical wires. - Uses for photovoltaics include supplying power to satellites and space vehicles and commercial uses such as a power source in remote areas for electrical equipment such as water-level sensors, meteorological stations, and emergency telephones. - It is emerging as a significant contributor to developing countries that do not have the financial abilities to build large central power plants that burn fossil fuels (cost of less than $400 per household). This is convenient for homes mostly in villages that are not link...

What are the costs and benefits of active solar heating systems? Answer: Solar collectors are experiencing rapid growth. The global market grew about 50% from 2001-2004. Solar water heating systems are economically viable, paying for themselves in only four to eight years.