Term
| cloudiness and PV-output rules of thumb |
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Definition
about 80% output on partly cloudy days
about 50% output on hazy humid days
about 30% output on extremely overcast days |
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Term
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Definition
| direct conversion of light into electricity at the atomic level |
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Term
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Definition
| causes some materials to absorb photons of light and release electrons |
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Term
| most productive hours of sunlight |
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Definition
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Term
| pv arrays that tract the sun across the sky can increase the power production of the array by_____ |
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Definition
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Term
| only ________ of solar radiation striking a pv module is converted into electricty |
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Definition
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Term
| three basic types of pv modules: |
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Definition
1. crystalline
2. thin film
3. solar ink |
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Term
| traditional solar cells made from silicon, usually flat-plate, generally the most efficient |
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Definition
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Term
| second-gen. solar cells made from amorphous silicon or non-silicon materials such as cadmium telluride |
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Definition
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Term
| third-gen solar cells made from variety of new materials besides silicon, including solar inks using conventional printing press tech, solar dyes, and conductive plastics |
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Definition
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Term
| four types of solar collectors |
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Definition
batch collectors (hot water)
flat plate collector (hot water)
evacuated tube collector (hot water)
transpired collectors + solar furnace (hot air) |
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Term
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Definition
| consist of one or more storage tanks placed in insulated boxes with their glazed, heat-absorbing sides facing the sun |
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Term
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Definition
| most common collector type; thin rectangular box with a transparent or translucent cover, usually installed on a building's roof |
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Term
| how a flat plate collector works |
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Definition
| small tubes run through the box carrying either water or an antifreeze solution to a black absorbed plate -- absorber plate absorbs radiation and quickly heats up; heat is transferred to the circulating fluid |
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Term
| evacuated tube collectors |
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Definition
| consist of parallel rows of transparent glass tubes each containing an absorber tube with a selective surface coating; solar radiation enters the tube, strikes the absorber, heats a freeze protected liquid flowing through the absorber |
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Term
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Definition
| south-facing exterior wall covered by a dark sheet metal collector which heats indoor air which is drawn into the building through perforations in the collector |
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