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--- luminous:glossary [2008-02-23 12:28] – created takufoam
+++ luminous:glossary [2008-02-23 12:49] – takufoam
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-PV-Vocabulary
+===== PhoEf glossary =====
-D-Solar Cell: capture photons from sunlight using an array of miniature “tower” structures that resemble high-rise buildings in a city street grid. Animation on: www.gatech.edu/news-room/flash/CNTpv.html
+**3D-Solar Cell:** capture photons from sunlight using an array of miniature “tower” structures that resemble high-rise
+buildings in a city street grid. Animation on: www.gatech.edu/news-room/flash/CNTpv.html
-Amp: short for ampere, the unit used to measure the instantaneous flow of electrons, theoretically, 6.02x1023 electrons.
+**Amp:** short for ampere, the unit used to measure the instantaneous flow of electrons, theoretically, 6.02x1023 electrons.
-Amp-hour: measure of a batteries ability to sustain a flow of energy over time; 60 amp-hours indicated a battery can deliver one amp for sixty hours.
-Balance of System (components): the complete system minus the modules.
-Base-load electricity: the smallest amount of electricity consumed by a utility's customers. Baseload is provided by slow-to-start, relatively inexpensive-to-operate generators, while peak-load is provided by quickly dispatchable sources.
-Biodegradation: is the decomposition of organic material by microorganisms. The term is often used in relation to sewage treatment, environmental remediation (bioremediation) and to plastic materials.
-Charge controller: the device in a stand-alone energy system that feeds electricity from the source, typically a PV array, to the battery bank. The charge controller protects the batteries from overcharging.
-Clean energies: Clean describes any energy source the exploitation of which does not generate significant amounts of pollution, and therefore negatively impact the health of human populations and the biosphere as a whole.
-Current: flow. In a river, the current is usually strongest near the center where the river is deepest. In electrical terms, current means the electrons flowing through a conductor, and is measured in amperes, one amp meaning 6.02x1023 electrons.
-Distributed energies: Distributed describes any energy source that can be deployed – often rapidly - on small, medium or large scales close to the point of consumption.
-Distributed generation (DG): contrasts with centralized generation, a term that characterizes conventional large-scale fossil fuel or nuclear power plant generation.
-Doping: Semiconductors into which tiny quantities of impurities (boron, phosphorus) have been deliberately diffused. This process dramatically alters the behaviour of the semiconductor in a very usefull manner.
-Efficiencies of a PV cell/module/system: the ratio of the maximum electric power and the power of the incident light. The amount of solar energy that strikes the Earth's surface is the equivalent of about 1 kW per square meter. This works out to 1 kiloWatt per hour (kWh) worth of sunlight per hour. A PV-system with an overall conversion efficiency of 10% would produce 0.1 kWh of electricity per hour.
-Usually efficiencies are determined under standard test conditions of 1,000 W/m2 illumination and 25°C. The spectral distribution of the light is expressed in terms of an optical air mass (AM) number. AM0 corresponds to the spectrum in space, AM1 to the spectrum at the earth's surface when the sun is overhead, AM2 when the sun is 60° off overhead, etc. (idealized cases). Cells and modules for terrestial use are generally measured under AM1 or AM1.5 conditions.
-Electrolysis: a chemical process in which the hydrogen and oxygen atoms in water are separated by the application of electricity. (4)
+**Amp-hour:** measure of a batteries ability to sustain a flow of energy over time; 60 amp-hours indicated a battery can deliver one amp for sixty hours.
-Electrolyte: "battery juice"; in lead-acid batteries, more-or-less dilute sulfuric acid. Consumer batteries use a solid electrolyte made up of filler impregnated with chemicals. The electrolyte allows ions to migrate to the battery's anode and cathode and react, producing a flow of electricity.
-Energy Payback Time: the time required to produce an amount of energy that is equal to the amount of energy consumed during the fabrication (of the device).
-Energy Return on Investment: is the ratio of electricity generated, divided by the energy required to build and maintain the equipment.
-External Costs (aka Externality): arises when the social or economic activities of one group of persons have an impact on another group and when that impact is not fully accounted, or compensated for, by the first group. Thus, a power station that generates emissions of SO2, causing damage to building materials or human health, imposes an external cost. This is because the impact on the owners of the buildings or on those who suffer damage to their health is not taken into account by the generator of the electricity when deciding on the activities causing the damage. In this example, the environmental costs are "external" because, although they are real costs to these members of society, the owner of the power station is not taking them into account when making decisions. Note that external costs are unintended and result from there being no property rights or markets for these environmental effects. The potential value of the Externality project therefore lies in valuing external costs in order for those values to be included in the design of policy to correct for the present lack of such property rights and markets.
-Field Assisted Simultaneous Synthesis and Transfer (FASST): A patented nanotechnology printing process (Heliovolt) which allows solar cells to be printed directly on metal, glass and other building materials.
+**Balance of System** (components): the complete system minus the modules.
-Fuel cell: is an electrochemical device similar to a battery, but differing from the latter in that it is designed for continuous replenishment of the reactants consumed; i.e. it produces electricity from an external fuel supply of hydrogen and oxygen as opposed to the limited internal energy storage capacity of a battery.
+**Base load electricity:** the smallest amount of electricity consumed by a utility's customers. Base load is provided **Clean energies:** Clean describes any energy source the exploitation of which does not generate significant amounts of pollution, and therefore negatively impact the health of human populations and the biosphere as a whole.
-Grid-excited inverter: an inverter changes DC electricity -- the kind that comes out of PVs -- into AC or house current. A grid-excited inverter, which is connected to the power grid and exports locally-harvested electricity into it, only operates when the grid is energized.
-Inverter: a device that converts DC electricity, as produced by PVs and stored in batteries, into AC house current, the kind used by most familiar household devices.
+**Current:** flow. In a river, the current is usually strongest near the center where the river is deepest. In electrical terms, current means the electrons flowing through a conductor, and is measured in amperes, one amp meaning 6.02x1023 electrons.
-KW: - kiloWatt.  1 kiloWatt=  1000 Watt – Unit of power. 1000 kW= 1 megaWatt (mW), 1000 megaWatt = 1 gigaWatt, 1000 gigaWatt = 1 teraWatt.
+**Distributed energies:** Distributed describes any energy source that can be deployed – often rapidly - on small, medium or large scales close to the point of consumption.
-kWh – kiloWatt hour: labour done by letting work 1000 Watt during 1 hour.
+**Distributed generation (DG):** contrasts with centralized generation, a term that characterizes conventional large-scale fossil fuel or nuclear power plant generation.
-Lead-acid batteries: the commonest and most cost-effective form of storage batteries, found in vehicles, uninterruptible power supplies, and renewably powered home systems.
-Load: in electricity, any device that consumes electricity, so an electric water heater is a big load, and a clock or a night light is a little load.
+**Doping:** semiconductors into which tiny quantities of impurities (boron, phosphorus) have been deliberately diffused. This process dramatically alters the behavior of the semiconductor in a very useful manner.
-Low-voltage: in electrical terms, less than house current, typically 12 or 24 volts.
+**Efficiencies of a pv-cell/module/system:** the ratio of the maximum electric power and the power of the incident light. The amount of solar energy that strikes the Earth's surface is the equivalent of about 1 kW per square meter. This works out to 1 kiloWatt per hour (kWh) worth of sunlight per hour. A PV-system with an overall conversion efficiency of 10% would produce 0.1 kWh of electricity per hour. Usually efficiencies are determined under standard test conditions of 1,000 W/m2 illumination and 25°C. The spectral distribution of the light is expressed in terms of an optical air mass (AM) number. AM0 corresponds to the spectrum in space, AM1 to the spectrum at the earth's surface when the sun is overhead, AM2 when the sun is 60° off overhead, etc. (idealized cases). Cells and modules for terrestrial use are generally measured under AM1 or AM1.5 conditions.
-Lumens: an exact measure of quantity of light. A 60-watt incandescent lightbulb and an 18-watt compact fluorescent light bulb each produce about 1,000 lumens.
+**Electrolysis:** a chemical process in which the hydrogen and oxygen atoms in water are separated by the application of electricity.
-megawatt peak of PV-modules: is the amount that delivers 1 MW of electric
+**Electrolyte:** "battery juice"; in lead-acid batteries, more-or-less dilute sulfuric acid. Consumer batteries use a solid electrolyte made up of filler impregnated with chemicals. The electrolyte allows ions to migrate to the battery's anode and cathode and react, producing a flow of electricity.
-power under standard illumination conditions (1,000 W/m2, 25 or 28 C)).
-MPP- tracking - Maximum Power Point Tracking: - a transformer has to deliver the max. power at all possible light circumstances which goes with a certain voltage delivered by the panel. This voltage depends on the amount of light falling on the panel. Power is the product of voltage and current and hence at a givven voltage there is a specific current. At every voltage there is an optimal current (maximum power point). In the invertor the electronical parts look under every circumstances this optimal point: MPP-tracking
+**Energy Payback Time:** the time required to produce an amount of energy that is equal to the amount of energy consumed during the fabrication (of the device).
-Mono-Crystalline Silicon Cells: high-grade, single-crystal, high-efficiency PV cells sliced from a single crystalline boule of purified silicon
-Multicrystalline (polycrystalline) Silicon Cells: many crystals of silicon in a semi-chaotic state, typical of medium-grade, medium-efficiency photovoltaic material.
+**Energy Return on Investment:** is the ratio of electricity generated, divided by the energy required to build and maintain the equipment.
-Ohm's Law: the mathematical product of current and voltage, P=IV.
+**External Costs (aka Externality):** arises when the social or economic activities of one group of persons have an impact on another group and when that impact is not fully accounted, or compensated for, by the first group. Thus, a power station that generates emissions of SO2, causing damage to building materials or human health, imposes an external cost. This is because the impact on the owners of the buildings or on those who suffer damage to their health is not taken into account by the generator of the electricity when deciding on the activities causing the damage. In this example, the environmental costs are "external" because, although they are real costs to these members of society, the owner of the power station is not taking them into account when making decisions. Note that external costs are unintended and result from there being no property rights or markets for these environmental effects. The potential value of the Externality project therefore lies in valuing external costs in order for those values to be included in the design of policy to correct for the present lack of such property rights and markets.
-Open-circuit voltage (Voc): is the voltage across the positive and negative terminals under open-circuit conditions, and the current is zero, which corresponds to a load resistance of infinity. (See Short-circuit current (Isc))
+**Field Assisted Simultaneous Synthesis and Transfer (FASST):** A patented nanotechnology printing process (Heliovolt) which allows solar cells to be printed directly on metal, glass and other building materials.
-Organic Photovoltaic (OPV): refers to polymers that are capable of generating electrical power from light.
+**Fuel cell:** is an electrochemical device similar to a battery, but differing from the latter in that it is designed for continuous replenishment of the reactants consumed; i.e. it produces electricity from an external fuel supply of hydrogen and oxygen as opposed to the limited internal energy storage capacity of a battery.
-Over-voltage: a circumstance in which the voltage is too high -- sun shining on a PV array on a cold day with snow on the ground might produce more voltage than a charge controller can handle, and so the over-voltage protection cuts the connection.
+**Grid-excited inverter:** an inverter changes DC electricity -- the kind that comes out of PVs -- into AC or house current. A grid-excited inverter, which is connected to the power grid and exports locally-harvested electricity into it, only operates when the grid is energized.
-Passive Solar: The natural power of solar heat and light. Many buildings are designed to take advantage of this natural resource through the use of passive solar heating and daylighting.
+**Inverter:** a device that converts DC electricity, as produced by PVs and stored in batteries, into AC house current, the kind used by most familiar household devices.
-The south side of a building always receives the most sunlight. Therefore, buildings designed for passive solar heating usually have large, south-facing windows. Materials that absorb and store the sun's heat can be built into the sunlit floors and walls. The floors and walls will then heat up during the day and slowly release heat at night, when the heat is needed most. This passive solar design feature is called direct gain.
-Other passive solar heating design:
+**KW:** kiloWatt.  1 kiloWatt=  1000 Watt – Unit of power. 1000 kW= 1 megaWatt (mW), 1000 megaWatt = 1 gigaWatt, 1000 gigaWatt = 1 teraWatt.
-Sunspace: (much like a greenhouse) is built on the south side of a building. As sunlight passes through glass or other glazing, it warms the sunspace. Proper ventilation allows the heat to circulate into the building.
-Trombe wall: is a very thick, south-facing wall, which is painted black and made of a material that absorbs a lot of heat. A pane of glass or plastic glazing, installed a few inches in front of the wall, helps hold in the heat. The wall heats up slowly during the day. Then as it cools gradually during the night, it gives off its heat inside the building.
+**kWh – kiloWatt hour:** labor done by letting work 1000 Watt during 1 hour.
+**Lead-acid batteries:** the commonest and most cost-effective form of storage batteries, found in vehicles, uninterruptible power supplies, and renewable energy powered home systems.
+**Load:** in electricity, any device that consumes electricity, so an electric water heater is a big load, and a clock or a night light is a little load.
+**Low-voltage:** in electrical terms, less than house current, typically 12 or 24 volts.
+**Lumens:** an exact measure of quantity of light. A 60-watt incandescent light bulb and an 18-watt compact fluorescent light bulb each produce about 1,000 lumen.
+**1 megawatt peak of pv-modules:** is the amount that delivers 1 MW of electric power under standard illumination conditions (1,000 W/m2, 25 or 28 C)).
+**MPP- tracking - Maximum Power Point Tracking:** - a transformer has to deliver the max. power at all possible light circumstances which goes with a certain voltage delivered by the panel. This voltage depends on the amount of light falling on the panel. Power is the product of voltage and current and hence at a given voltage there is a specific current. At every voltage there is an optimal current (maximum power point). In the inverter the electronic parts look under every circumstances this optimal point: MPP-tracking
+**Mono-Crystalline Silicon Cells:** high-grade, single-crystal, high-efficiency PV cells sliced from a single crystalline boule of purified silicon
+**Multicrystalline (polycrystalline) Silicon Cells:** many crystals of silicon in a semi-chaotic state, typical of medium-grade, medium-efficiency photovoltaic material.
+**Ohm's Law:** the mathematical product of current and voltage, P=IV.
+**Open-circuit voltage (Voc):** is the voltage across the positive and negative terminals under open-circuit conditions, and the current is zero, which corresponds to a load resistance of infinity. (See Short-circuit current (Isc))
+**Organic Photovoltaic (OPV):** refers to polymers that are capable of generating electrical power from light.
+**Over-voltage:** a circumstance in which the voltage is too high - sun shining on a pv-array on a cold day with snow on the ground might produce more voltage than a charge controller can handle, and so the over-voltage protection cuts the connection.
+**Passive Solar:** the natural power of solar heat and light. Many buildings are designed to take advantage of this natural resource through the use of passive solar heating and daylighting. The south side of a building always receives the most sunlight. Therefore, buildings designed for passive solar heating usually have large, south-facing windows. Materials that absorb and store the sun's heat can be built into the sunlit floors and walls. The floors and walls will then heat up during the day and slowly release heat at night, when the heat is needed most. This passive solar design feature is called direct gain. Other passive solar heating design:
+- //Sunspace:// (much like a greenhouse) is built on the south side of a building. As sunlight passes through glass or other glazing, it warms the sun space. Proper ventilation allows the heat to circulate into the building.
+- //Trombe wall:// is a very thick, south-facing wall, which is painted black and made of a material that absorbs a lot of heat. A pane of glass or plastic glazing, installed a few inches in front of the wall, helps hold in the heat. The wall heats up slowly during the day. Then as it cools gradually during the night, it gives off its heat inside the building.
 Peak Watt: is the amount of power produced when the module receives 1,000 watts per square meter of exposure to the sun (insolation). It is used for rating PV-Systems.