The 32 megawatt AC Long Island Solar Farm (LISF), located in Upton, New York , was the largest photovoltaic array in the eastern U.S. in November 2011. The LISF is made up of 164,312 solar panels from BP Solar which provide enough electricity for roughly 4,500 households. The project will cause the abatement of more than 30,000 metric tons of carbon dioxide emissions per year. LISF is co-owned by BP Solar and MetLife through Long Island Solar Farm LLC. Municipal utility Long Island Power Authority (LIPA) buys the 37- megawatt (49,600 hp ) power plant's output, which is estimated at 44 GWh annually, under a 20-year power purchase agreement (PPA). Payments over that time are expected to total $ 298 million (34¢/kWh, 60¢/LIPA customer/month). The project was engineered by Blue Oak Energy and construction subcontracted to Hawkeye LLC from Hauppauge, New York. The plant earned the Best Photovoltaic Project of Year Award from the New York Solar Energy Industries Association. The panels are mounted at a fixed tilt angle of 35°, with the rows spaced approximately 18 ft 4 in (5.59 m) apart.
16-445: The solar farm uses 25 of the 1.25 MVA inverters and a 34.5 kV collector system. Since the connection to the grid is at 69 kV, and acquiring a spare step-up transformer of that capacity has a long lead time, a spare transformer is maintained onsite. Each inverter has an associated meteorological station to help researchers correlate plant output with observed and predicted weather, to help learn how to integrate photovoltaics into
32-427: A battery is determined by the chemistry of that cell (see Galvanic cell § Cell voltage ). Cells can be combined in series for multiples of that voltage, or additional circuitry added to adjust the voltage to a different level. Mechanical generators can usually be constructed to any voltage in a range of feasibility. Nominal voltages of familiar sources: In 1800, as the result of a professional disagreement over
48-480: A Clean Solar Initiative which will install an additional 50 MW of solar photovoltaics, to be paid $ 0.22/kWh over a 20-year period. 5 MW is reserved for small systems of from 50 kW to 150 kW, 10 MW for systems from 150 kW to 500 kW, and the remaining 35 MW is for systems of any size, up to 20 MW. All systems must be connected to the grid at the 13.2 kV level. Systems connected before July 2012 are not eligible. Kilovolt The volt (symbol: V )
64-441: A ratio because the cgs unit of voltage is inconveniently small and one volt in this definition is approximately the emf of a Daniell cell , the standard source of voltage in the telegraph systems of the day. At that time, the volt was defined as the potential difference [i.e., what is nowadays called the "voltage (difference)"] across a conductor when a current of one ampere dissipates one watt of power. The "international volt"
80-533: A series-connected array of several thousand or tens of thousands of junctions , excited by microwave signals between 10 and 80 GHz (depending on the array design). Empirically, several experiments have shown that the method is independent of device design, material, measurement setup, etc., and no correction terms are required in a practical implementation. In the water-flow analogy , sometimes used to explain electric circuits by comparing them with water-filled pipes, voltage (difference in electric potential)
96-414: Is also equivalent to electronvolts per elementary charge : The volt is named after Alessandro Volta . As with every SI unit named for a person, its symbol starts with an upper case letter (V), but when written in full, it follows the rules for capitalisation of a common noun ; i.e., volt becomes capitalised at the beginning of a sentence and in titles but is otherwise in lower case. Historically
112-606: Is likened to difference in water pressure , while current is proportional to the amount of water flowing. A resistor would be a reduced diameter somewhere in the piping or something akin to a radiator offering resistance to flow. The relationship between voltage and current is defined (in ohmic devices like resistors ) by Ohm's law . Ohm's Law is analogous to the Hagen–Poiseuille equation , as both are linear models relating flux and potential in their respective systems. The voltage produced by each electrochemical cell in
128-566: Is the elementary charge and h is the Planck constant ), a "conventional" value K J-90 = 0.4835979 GHz/μV was used for the purpose of defining the volt. As a consequence of the 2019 revision of the SI , as of 2019 the Josephson constant has an exact value of K J = 483 597 .848 416 98 ... GHz/V , which replaced the conventional value K J-90 . This standard is typically realized using
144-435: Is the potential difference between two points that will impart one joule of energy per coulomb of charge that passes through it. It can be expressed in terms of SI base units ( m , kg , s , and A ) as It can also be expressed as amperes times ohms (current times resistance, Ohm's law ), webers per second (magnetic flux per time), watts per ampere (power per current), or joules per coulomb (energy per charge), which
160-500: Is the unit of electric potential , electric potential difference ( voltage ), and electromotive force in the International System of Units (SI) . One volt is defined as the electric potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points. It can be expressed in terms of SI base units ( m , kg , s , and A ) as Equivalently, it
176-491: The " conventional " volt, V 90 , defined in 1987 by the 18th General Conference on Weights and Measures and in use from 1990 to 2019, was implemented using the Josephson effect for exact frequency-to-voltage conversion, combined with the caesium frequency standard . Though the Josephson effect is still used to realize a volt, the constant used has changed slightly. For the Josephson constant , K J = 2 e / h (where e
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#1732859175579192-678: The British Association for the Advancement of Science had defined the volt, ohm, and farad. In 1881, the International Electrical Congress, now the International Electrotechnical Commission (IEC), approved the volt as the unit for electromotive force. They made the volt equal to 10 cgs units of voltage, the cgs system at the time being the customary system of units in science. They chose such
208-525: The 💕 For the enclosure housing electrical connections, see Junction box . An electrical junction is a point or area where (a) two or more conductors or (b) different semiconducting regions of differing electrical properties make physical contact. Electrical junctions types include thermoelectricity junctions, metal–semiconductor junctions and p–n junctions . Junctions are either rectifying or non-rectifying. Non-rectifying junctions comprise ohmic contacts , which are characterised by
224-415: The galvanic response advocated by Luigi Galvani , Alessandro Volta developed the so-called voltaic pile , a forerunner of the battery , which produced a steady electric current . Volta had determined that the most effective pair of dissimilar metals to produce electricity was zinc and silver . In 1861, Latimer Clark and Sir Charles Bright coined the name "volt" for the unit of resistance. By 1873,
240-601: The power grid. A formal case study of the development of the Long Island Solar Farm was published by the U.S. Department of Energy in May 2013. The 17 MW (AC) Eastern Long Island Solar Project or Suffolk Solar Carport Project consists of a group of projects, three at LIRR carparks. $ 124 million has been allocated to pay for the electricity generated, over 20 years, from the project (approximately 27¢/kWh). Plans to install solar panels at Ronkonkoma LIRR have stalled. LIPA has
256-427: Was defined in 1893 as 1 ⁄ 1.434 of the emf of a Clark cell . This definition was abandoned in 1908 in favor of a definition based on the international ohm and international ampere until the entire set of "reproducible units" was abandoned in 1948. A 2019 revision of the SI , including defining the value of the elementary charge , took effect on 20 May 2019. Electrical junction From Misplaced Pages,
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