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**External Costs (aka Externality): | **External Costs (aka Externality): | ||
- | **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. | + | **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. |
- | 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. | + | **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. |
- | 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 | + | **Grid-excited inverter:** an inverter changes |
- | KW: - kiloWatt. | + | **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. |
- | kWh – kiloWatt hour: labour done by letting work 1000 Watt during 1 hour. | + | **KW:** kiloWatt. |
- | Lead-acid batteries: the commonest and most cost-effective form of storage batteries, found in vehicles, uninterruptible | + | |
- | Load: in electricity, | + | **kWh – kiloWatt hour:** labor done by letting work 1000 Watt during 1 hour. |
- | Low-voltage: in electrical terms, less than house current, typically 12 or 24 volts. | + | **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. |
- | Lumens: an exact measure of quantity of light. A 60-watt incandescent lightbulb | + | **Load:** in electricity, |
- | 1 megawatt peak of PV-modules: is the amount that delivers 1 MW of electric | + | **Low-voltage:** in electrical terms, less than house current, typically 12 or 24 volts. |
- | 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 | + | **Lumens:** an exact measure of quantity of light. |
- | Mono-Crystalline Silicon Cells: high-grade, single-crystal, | + | |
- | Multicrystalline (polycrystalline) Silicon Cells: many crystals | + | **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)). |
- | Ohm's Law: the mathematical | + | **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 |
- | 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 | + | **Mono-Crystalline Silicon Cells:** high-grade, single-crystal, high-efficiency PV cells sliced from a single crystalline boule of purified silicon |
- | Organic Photovoltaic | + | **Multicrystalline |
- | Over-voltage: a circumstance in which the voltage | + | **Ohm' |
- | 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. | + | **Open-circuit voltage |
- | 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: | + | |
- | Trombe wall: is a very thick, south-facing wall, which is painted black and made of a material that absorbs | + | |
- | Peak Watt: is the amount | + | **Organic Photovoltaic (OPV):** refers to polymers that are capable |
- | Photon: refers to a " | + | **Over-voltage:** a circumstance |
- | Peak oil: is the point in time when the maximum rate of global petroleum production is reached, after which the rate of production enters its terminal decline. If global consumption is not mitigated before the peak, an energy crisis may develop because the availability of conventional oil will drop and prices will rise, perhaps dramatically. | + | **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: |
+ | - // | ||
+ | - //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. | ||
+ | |||
+ | **Photon:** refers to a " | ||
+ | |||
+ | **Peak oil:** is the point in time when the maximum rate of global petroleum production is reached, after which the rate of production enters its terminal decline. If global consumption is not mitigated before the peak, an energy crisis may develop because the availability of conventional oil will drop and prices will rise, perhaps dramatically. | ||
Photovoltaic effect: the generation of a voltage and/or a current by absorption of light in some material or combination of materials. | Photovoltaic effect: the generation of a voltage and/or a current by absorption of light in some material or combination of materials. | ||
- | Photovoltaics: | + | **Photovoltaics: |
- | Photovoltaic cell (see also Solar cell): is a device that converts light energy into electrical energy by the photovoltaic effect. Sometimes the term solar cell is reserved for devices intended specifically to capture energy from sunlight, while the term photovoltaic cell is used when the source is unspecified. | + | **Photovoltaic cell** (see also Solar cell): is a device that converts light energy into electrical energy by the photovoltaic effect. Sometimes the term solar cell is reserved for devices intended specifically to capture energy from sunlight, while the term photovoltaic cell is used when the source is unspecified. |
- | Quantum Dot: also called a semiconductor nanocrystal, | + | **Quantum Dot:** also called a semiconductor nanocrystal, |
- | Quantum efficiency (QE): is the ratio of the number of charge carriers collected by the solar cell to the number of photons — or packets of light — of a given energy shining on the solar cell. | + | **Quantum efficiency (QE):** is the ratio of the number of charge carriers collected by the solar cell to the number of photons — or packets of light — of a given energy shining on the solar cell. |
- | Renewable energies: Renewable describes any energy source whose availability or supply will not be permanently depleted as a result of exploitation over a period of time that is meaningful to people. Fossil fuels (coal, oil and natural gas), which formed over millions of years of geological conditioning, | + | **Renewable energies:** Renewable describes any energy source whose availability or supply will not be permanently depleted as a result of exploitation over a period of time that is meaningful to people. Fossil fuels (coal, oil and natural gas), which formed over millions of years of geological conditioning, |
- | Semi-conductor: | + | **Semi-conductor: |
- | Short-circuit current (Isc): is the current produced when the positive and negative terminals of the cell are short-circuited, | + | **Short-circuit current (Isc):** is the current produced when the positive and negative terminals of the cell are short-circuited, |
- | Solar cell (see also " | + | **Solar cell (see also " |
Fundamentally, | Fundamentally, | ||
- | 1. photogeneration of charge carriers (electrons and holes) in a light-absorbing material, and 2. separation of the charge carriers to a conductive contact that will transmit the electricity. This conversion is called the photovoltaic effect. | + | 1. photogeneration of charge carriers (electrons and holes) in a light-absorbing material, and |
+ | 2. separation of the charge carriers to a conductive contact that will transmit the electricity. This conversion is called the photovoltaic effect. | ||
Photovoltaics is the field of research related to solar cells. Solar cells have many applications. Historically solar cells have been used in situations where electrical power from the grid is unavailable, | Photovoltaics is the field of research related to solar cells. Solar cells have many applications. Historically solar cells have been used in situations where electrical power from the grid is unavailable, | ||
- | + | **Solar cell's energy conversion efficiency**: is the percentage of power converted from absorbed light to electrical energy and then collected when a solar cell is connected to an electrical circuit. | |
- | Solar cell's energy conversion efficiency: is the percentage of power converted from absorbed light to electrical energy and then collected when a solar cell is connected to an electrical circuit. | + | |
Or: | Or: | ||
The efficiency of a solar cell is defined as the percentage of solar energy falling on its surface that is converted into electrical energy. | The efficiency of a solar cell is defined as the percentage of solar energy falling on its surface that is converted into electrical energy. | ||
Under a typical sunny day, a one square meter surface of solar cells exposed to the sun around noontime will receive approximately 1,000 W. When for instance multi silicon cells convert 15% of this into electricity, | Under a typical sunny day, a one square meter surface of solar cells exposed to the sun around noontime will receive approximately 1,000 W. When for instance multi silicon cells convert 15% of this into electricity, | ||
- | Solar Cycle: The 11-year variation in the Sun's magnetic field and all the features caused by it such as the number of sunspots, coronal mass ejections and solar flares. The variation is seen as an increase and decrease of solar activity on a regular basis, lasting approximately 11 years from beginning of end. | + | **Solar Cycle:** The 11-year variation in the Sun's magnetic field and all the features caused by it such as the number of sunspots, coronal mass ejections and solar flares. The variation is seen as an increase and decrease of solar activity on a regular basis, lasting approximately 11 years from beginning of end. |
- | Solar-hydrogen fuel cell energy system: a photovoltaic array produces electricity to provide for the primary electricity load (home), as well as enough excess electricity to run an electrolyzer which converts water into hydrogen. The hydrogen produced will be reserved in a storage tank until needed, at which point it will be converted back into electricity through means of a fuel cell. To increase energy efficiency. | + | **Solar-hydrogen fuel cell energy system:** a photovoltaic array produces electricity to provide for the primary electricity load (home), as well as enough excess electricity to run an electrolyzer which converts water into hydrogen. The hydrogen produced will be reserved in a storage tank until needed, at which point it will be converted back into electricity through means of a fuel cell. To increase energy efficiency. |
If 1% of the world' | If 1% of the world' | ||
- | Solar panels: are devices for capturing the energy in sunlight. The term solar panel can be applied to either solar hot water panels (usually used for providing domestic hot water) or solar photovoltaic panels (providing electricity). | + | **Solar panels:** are devices for capturing the energy in sunlight. The term solar panel can be applied to either solar hot water panels (usually used for providing domestic hot water) or solar photovoltaic panels (providing electricity). |
- | Solar power: describes a number of methods of harnessing energy from the light of the Sun. It has been present in many traditional building methods for centuries, but has become of increasing interest in developed countries as the environmental costs and limited supply of other power sources such as fossil fuels are realized. | + | **Solar power:** describes a number of methods of harnessing energy from the light of the Sun. It has been present in many traditional building methods for centuries, but has become of increasing interest in developed countries as the environmental costs and limited supply of other power sources such as fossil fuels are realized. |
- | Solar Power Concentrated (PhotoVoltaics) (CSP;CPV): use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam capable of producing high temperatures and correspondingly high thermodynamic efficiencies. Concentrating solar is generally associated with solar thermal applications but concentrating photovoltaic (CPV) applications exist as well and these technologies also exhibit improved efficiencies. CSP systems require direct | + | **Solar Power Concentrated (PhotoVoltaics) (CSP;CPV):** use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam capable of producing high temperatures and correspondingly high thermodynamic efficiencies. Concentrating solar is generally associated with solar thermal applications but concentrating photovoltaic (CPV) applications exist as well and these technologies also exhibit improved efficiencies. CSP systems require direct |
- | Solar (ir)radiation: | + | **Solar (ir)radiation: |
- | Daily total solar irradiation: | + | - Daily total solar irradiation: |
| | ||
- | Solar wind: A stream of particles, mostly electrons and protons, flowing out from the Sun at speeds of 5-10 km/s. As it flows out, the solar wind accelerates and can reach speeds as high as 900 km/s. The solar wind is the result of the hot solar corona expanding into space. | + | **Solar wind:** A stream of particles, mostly electrons and protons, flowing out from the Sun at speeds of 5-10 km/s. As it flows out, the solar wind accelerates and can reach speeds as high as 900 km/s. The solar wind is the result of the hot solar corona expanding into space. |
Sun-Earth distance: varies during the year, but on average it is approximately 150,000,000 km or 93,000,000 miles. | Sun-Earth distance: varies during the year, but on average it is approximately 150,000,000 km or 93,000,000 miles. | ||
- | Under-voltage: | + | **Under-voltage: |
- | Ultra Violet-Light (UV): means " | + | **Ultra Violet-Light (UV):** means " |
- | Wp - Watt-piek | + | **Wp - Watt-piek:** Max. theoretical power of a solar panel with a surface of 1m², measured at a temperature of 25°. A standard measure (unit) being used to compare the power of different solar panels. In practice a solar panel reaches in general only 80% of the Watt-piek power. |
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