Chapter 12 Glossary Terms

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Chapter 12 Glossary Terms
2014-11-02 21:24:00
msday electricity

Chapter 12 Glossary Terms
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  1. What are the 2 types of current?
    • Direct current (DC) - A current in which charged particles travel through a circuit in only one direction. e.g. Electrons in a cell move from the negative terminal to the positive terminal, only moving in one direction.
    • Alternating current (AC) - A current in which electrons move back and forth in a circuit. There is no net movement of electrons in either direction.
  2. What is a transformer?
    An electrical device that changes the size of the potential difference of an alternating current. Transformers don't work with direct current, and that is why alternating current is used in homes, businesses, and factories. e.g. when a device, such as your phone, is plugged into a wall outlet to recharge it, a transformer reduces the potential difference to the potential difference needed.
  3. What is a circuit breaker?
    A safety device that is placed in series with other circuits, which lead to appliances and outlets. The distribution panel in a house consists of circuit breakers.
  4. What is a fuse?
    A fuse is a safety device that is found in older buildings and some appliances. It is placed in series with other circuits, which then lead to appliances and outlets.
  5. What is electrical power?
    The rate at which an appliance uses electrical energy. e.g. an electric stove uses about 3.5 kW of electrical energy, and usually smaller appliances use less electrical energy.
  6. What are watts and kilowatts?
    A watt (W) is a unit of electrical power, while kilowatt (kW) is a practical unit of electrical power, which is used for most appliances. One kW is equal to 1000W.
  7. What is electrical energy?
    The energy that is used by an appliance at a given setting. It is determined by multiplying the power rating of an appliance by the length of time it is used.
  8. What is kilowatt-hour (kW*h)?
    The practical unit of electrical energy, or also known as power x time. Another unit, in joules, would be J=Ws.
  9. What is an EnerGuide label?
    A label that gives details about how much energy an appliance uses in one year of normal use. Any household appliance in Canada must have an EnerGuide label. It is helpful when a consumer is looking for an appliance, which lets them see how efficient and how much energy the appliance uses.
  10. What is a smart meter?
    A smart meter records the total electrical energy used hour by hour and sends this information to the utility company automatically.
  11. What is time of use pricing?
    It is a system of pricing in which the cost of each kW*h of energy used is different at different times of the day. There are three different types of use prices, off-peak, mid-peak, and on-peak use. The prices are changed 2 times a year because of the seasons. All electricity bills are based on time of use pricing.
  12. What is a phantom load?
    The electricity that is consumed by an appliance or device when it is turned off. An average home has a phantom load of approximately 50 MW. The best way to prevent a phantom load is to unplug the appliance.
  13. What does efficiency for an appliance mean?
    The ratio of useful energy output to total energy input, and is expressed as a percentage. An efficient device does what you want it to do, with little conversion of energy to unwanted forms. The higher the efficiency more efficient the appliance is.
  14. What is a base load?
    The continuous minimum demand for electrical power. The base load is usually 12 000 MW. The base load is generated by hydroelectric and nuclear generating stations.
  15. What is hydroelectric power generation?
    The generation of electrical power using a source of moving water. The two types of hydroelectric plants are dam stations and run-of-river stations. Hydroelectric power generation depends on a large source of water to provide energy to turn turbines.
  16. What is an intermediate load?
    A demand for electricity that is greater than the base load and is met by burning coal and natural gas. The intermediate load is usually 15000-20000 MW.
  17. What is a peak load?
    It is the greatest demand for electricity, which is met by using hydroelectric power and natural gas. The peak load is usually above 20 000 MW (megawatts). The cost of providing energy is then increased.
  18. What is a renewable energy source?
    A source of energy that can be replaced in a relatively short period of time. e.g. hydroelectric energy,using water which can be replaced very quickly, unlike using fossil fuels.
  19. What is a non-renewable energy source?
    A source of energy that cannot be replaced as quickly as it is used. e.g. fossil fuels, such as natural gas, which is being quickly consumed by humans, and is not able replenish in time to fill the needs of humans.
  20. What is solar energy?
    It is the energy that is directly converted from the Sun into electricity. Solar energy is expensive, not very efficient, and not very concentrated, but it is a eco-friendly way of energy usage.
  21. What is the photovoltaic effect?
    The generation of a direct current when certain materials are exposed to light. A direct current is generated when light strikes the surface of photovoltaic materials in a solar cell. e.g. calculator or wrist watch, some of which have solar cells.
  22. What is biomass energy?
    It is the energy that is generated from plant and animal matter. The process of burning plant matter adds carbon dioxide to the atmosphere, but is said to be carbon neutral. Biomass energy results in less acid rain and no heavy metals are emitted.