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Less work is required to move heat than for conversion into heat, and because of this, heat pumps, air conditioners and refrigeration systems can have a coefficient of performance greater than one. The COP is highly dependent on operating conditions, especially absolute temperature and relative temperature between sink and system, and is often ...
Toshiba 660 MVA water cooled 23 kV AC turbo generator: 1,342 t 2,959,000 lb 660 MW 890,000 hp 0.49 kW/kg 0.30 hp/lb Bayswater, Eraring coal-fired power stations: Canopy Tech. Cypress 32 MW 15 kV AC PM generator [29] 33,557 kg 73,981 lb 32 MW 43,000 hp 0.95 kW/kg 0.58 hp/lb Electric power stations: Turncircles AF24PM–S axial flux motor [30]
Air-conditioner sizes are often given as "tons" of cooling, where 1 ton of cooling equals 12,000 BTU/h (3.5 kW). 1 ton of cooling equals the amount of power that needs to be applied continuously over a 24-hour period to melt 1 ton of ice. The annual cost of electric energy consumed by an air conditioner may be calculated as follows:
It was originally defined as the rate of heat transfer that results in the freezing or melting of 1 short ton (2,000 lb; 907 kg) of pure ice at 0 °C (32 °F) in 24 hours. [ 1 ] [ 2 ] The modern definition is exactly 12,000 Btu IT /h (3.516853 kW ).
The SI unit of power for heating and cooling systems is the watt. Btu per hour (Btu/h) is sometimes used in North America and the United Kingdom - the latter for air conditioning mainly, though "Btu/h" is sometimes abbreviated to just "Btu". [18] MBH—thousands of Btu per hour—is also common. [19] 1 W is approximately 3.412142 Btu/h [20]
This 4.25 x 6.15 x 1.75 inch calculator's processor would originate the vast majority of Texas Instruments’ revenue. [20] In 1973, the handheld calculator SR-10 (named after slide rule) and in 1974, the handheld scientific calculator SR-50 were issued by TI. Both had red LED-segments numeric displays.
Made in Japan, this was also the first calculator to use an LED display, the first hand-held calculator to use a single integrated circuit (then proclaimed as a "calculator on a chip"), the Mostek MK6010, and the first electronic calculator to run off replaceable batteries. Using four AA-size cells the LE-120A measures 4.9 by 2.8 by 0.9 inches ...
The nominal power of PV devices is measured under standard test conditions (STC), specified in standards such as IEC 61215, IEC 61646 and UL 1703. Specifically, the light intensity is 1000 W/m 2, with a spectrum similar to sunlight hitting the Earth's surface at latitude 35°N in the summer (airmass 1.5), the temperature of the cells being 25 °C.