Chapter 16 Test 4 All Answers Correct

Chapter 16 Test 4 All Answers Correct Solar collecting panels would be most effective if they were positioned nearest to the equator. Which of the following is true regarding renewable electricity production in the United States? of 2013, wind power had more electricity-generating capacity than solar photovoltaic power. As As of 2013, wind power had a generating capacity of about 61.1 gigawatts, whereas solar PV power had a capacity of only about 12.1 gigawatts. In order to make a rapid transition to renewable energies, countries such as the United States will have to reduce subsidies to the fossil fuel industry. About how much of the sun's radiation would strike the Earth if the Earth did not have its atmosphere? About twice as much Advantages and disadvantages of renewable energy sources no fossil fuel required for production-hydroelectric, solar, wind generation process is pollution free- solar and wind production can be increased on demand-hydroelectric infinitely renewable-solar and wind disadvantages- advantages geographically limited and harmful to nearby wildlife- hydroelectric, solar, wind In the solar panel system presented in the video, which of the following was necessary to generate usable electrical current for a home? DC power had to be converted to AC The solar panel generates DC current, which is not usually used in homes. Thus, the DC current must be converted to AC, which is the standard in homes. Which of the following best describes the energy conversion sequence in the solar panel system described in the video? Photons carrying energy from the sun chemically react with silicon crystals to generate a flow of electrons. The energy of the sun has to be converted into electricity. Which of the following would indicate that a home is using solar power to generate electricity and is NOT using batteries? There are solar panels on the roof and power lines going to the home. When the solar panel system is not generating enough electricity, or any at all at night, the home can draw upon the power grid. Therefore, the home does not require or use batteries for backup. if a home uses a large supply of solar panels to generate electricity, but has no battery system, surplus electricity that is produced is usually __________. released into the power grid for others to use, generating a credit to the homeowner This surplus energy therefore generates value to the homeowner whenever more electricity is produced than is needed. This helps to further offset the cost of the solar panel system. Which of the following is a challenge to using solar-generated electricity in places not connected to a power grid? the lack of efficient and inexpensive battery technology Current research in battery technology hopes to address this important need, which may also benefit the electric car industry. The ultimate source of energy that drives wind power is __________. the sun Sunlight heats the Earth's surfaces unevenly. Wind is the movement of air between these different regions. A typical wind farm in the United States consists of __________. clustered in a region with a low human population Very large wind turbines are more efficient systems many very large wind turbines The year 2030 goal set by the US Department of Energy is to generate __________. electricity using wind-powered systems 20% of Wind power will be only part of the solution to sustainable energy. Solar and other energy sources will still be required. Electricity in a wind turbine is generated __________. copper wire when spinning magnets move past a coil of This is the typical way that electricity is generated in many power systems. Producing electricity using wind instead of fossil fuels __________. in the process generates no carbon dioxide The use of fossil fuels generates tremendous amounts of atmospheric carbon dioxide, which contributes to global warming. Why is it important for renewable energy sources to replace fossil fuels? What are the prospects for getting it done? The salient reason is global climate change. Clearly the manufacture of wind turbines, PV panels, transmission lines, concentrated solar power plants, electric vehicles, recharging stations, and so on would have to take place in a relatively short period of time and this would require massive government support. Another barrier to accomplishing this transition is the way in which government subsidies. How much solar energy is available, and what happens when it is used? What are some problems with harnessing solar energy? Full sunlight can deliver about 700 watts per square meters to Earth's surface when the Sun is directly overhead. At that rate, the Sun can deliver 700 MW of to an area of 390 square miles. The Sun delivers 10,000 times the energy used by humans. If humans were to capture and obtain useful work from solar energy, it would still be converted into heat and lost in accordance with the Second Law of Thermodynamics. The overall energy balance would not change. The main problem with using solar energy is one of taking a diffuse and intermittent source and concentrating it into an amount and form, such as fuel and energy, that can used to provide heat and run vehicles, appliances, and other machinery. Also overcoming such obstacles must be cost effective. How do active and passive solar hot-water heaters work? In an active system, the heated water is moved by means of a pump. In a passive solar water-heating system, the system must be mounted so that the collector is lower than the tank. Thus, heated water from the collector rises by natural convection into the tank, while cooler water from the tank descends into the collector. How can a building best be designed to become a passive solar collector for heat? Typically, passive solar heating involves: The collection of solar energy through properly-oriented, south-facing windows. The storage of this energy in "thermal mass," comprised of building materials with high heat capacity such as concrete slabs, brick walls, or tile floors.