Module 12 quiz/ question set

Explain how the energy we capture from hydroelectriccould be traced ultimately to the Sun.

The Sun plays a crucial role in the water cycle in that it is the driving force. In order for the water to be in a cycle of motion, it is dependent on the Sun for its cycling and weather patterns.

What twoforms of energy humans use to commercially produce electricity cannotbe traced ultimately to the Sun?

Two forms of energy that can not be traced back to the Sun are geothermal and nuclear energy.

A geothermal-powered steam plant generates electricity by using heat originating in the _______ to boil water to produce ______ the force from it then turns a _____ which then spins a________ which produces electricity.

earth steam turbine generator

Electricity may be generated from the ocean

* By capturing motion of the waves. * Using current and tidal flows to turn a turbine. * Using the temperature differential between the surface water and deep water.

Give a disadvantage of each.

* Tidal energy can affect ecology of estuaries and tidal basins. * Wave energy can result in high levels of corrosion on the apparatus that captures the wave energy as a result of the salt in the ocean water.

Give an advantage of each.

* Tidal energy produces few or no pollutants. * There are many creative and innovative ways to capture wave energy that are renewable and 'clean'.

Describe oneway concentrated solar energy is used to produce electricity.

Flat plate solar collectors heat water and air for homes or businesses by absorbing solar energy from the sun.

Generating electricity from concentrated solar energy

* Could create thermal pollution. * May store heat energy to use at night. * Uses steam.

Explain what happens to produce two environmental problems from hydroelectric electricity production.

Problems arise from this kind of process from changes in the aquatic ecosystems and surrounding environment due to the creation and maintenance of the reservoirs. * For example, building dams and the water it impounds behind it have detrimental impacts on the river's ecosystem. * Dams block fish migration, and the turbines kill aquatic life. * Also, creating the large surface area of water increases overall water losses from subsequent evaporation.

Describetwo problems from collecting energy from the wind.

Problems from wind energy include the noise, high initial costs, killing birds, and the fact that it may change weather patterns by 'stealing' wind.

Explain how the energy we capture from windcould be traced ultimately to the Sun.

The energy we capture from wind can ultimately be traced back to the Sun due to the Sun causing the change of air pressures from the temperature differences it creates.

Describe how Ground-Source Heat Pumps (ground exchange) work to heat and cool buildings.

These pumps provide heating in the winter by transferring heat from the ground into buildings, and they provide cooling in the summer by transferring heat from buildings into the ground.

Describe two waysthat electricity may be produced from the kinetic energy of the ocean.

Tidal energy from the ocean can be harnessed by erecting dams across the outlets of tidal basins. These work by allowing the currents to pass through the dam, which then turns the turbines to generate electricity from the water passing through it. * Wave energy from the oceans attempts to harness the motion of ocean waves and convert their energy into electricity. The up and down motion of the waves may be used to move wire coils in a magnetic field to produce electricity or change air pressure in a closed space or a power pump to move air or water to turn a turbine.

The Sun is the ultimate source of power for

* Hydroelectric power *Electricity generated by fossil fuel combustion. * Wind-generated power.

Passive solar heating of buildings

* Is based on architecture. * Is becoming more efficient than before. * Uses structures to store heat.

Geothermal energy

* Is restricted to certain areas on Earth. * Uses steam to generate electricity.

Name the three ways geothermal energy is used to generate electricity.

* One method is to use geothermal heat directly from the earth, in the form of dry steam to produce electricity. * Another way is to use the hot geothermal water to heat another fluid to run the turbine to produce electricity. * The last way is to separate steam in an exchanger, and have that steam then turn the turbine.

Explain at least two basic differences between passive and active solar heating of buildings.

* Passive methods to heat buildings use positioning that is relative to the sun in order to capture, store, and transmit heat throughout the buildings. * Active methods use solar collectors as well as pumps and fans to actually move heat throughout the building.

Ocean thermal gradients

* Ultimately gets its energy from the Sun. * Use the temperature difference between the surface and deeper water to generate electricity. (DO NOT *Uses the up-and-down motion of waves to produce heat which is used to generate electricity. * May be used in all oceans.)

Active solar heating systems

*Use pumps to move heat. * Require dedicated solar collectors.

Outline the process of commercial electricity production from moving water.

Current methods to use moving water to turn a turbine to spin a generator to produce electricity.

Describe two advantages of collecting energy from the wind.

One advantage includes that it is a fast growing renewable energy resource. Another advantage is that it now provides 30% of our renewable energy needs.