Search results
Results from the WOW.Com Content Network
The utilization factor or use factor is the ratio of the time that a piece of equipment is in use to the total time that it could be in use. It is often averaged over time in the definition such that the ratio becomes the amount of energy used divided by the maximum possible to be used. These definitions are equivalent.
A UPS differs from a traditional auxiliary/emergency power system or standby generator in that it will provide near-instantaneous protection from input power interruptions by switching to energy stored in battery packs, supercapacitors or flywheels. The on-battery run-times of most UPSs are relatively short (only a few minutes) but sufficient ...
In electrical engineering the load factor is defined as the average load divided by the peak load in a specified time period. [1] It is a measure of the utilization rate, or efficiency of electrical energy usage; a high load factor indicates that load is using the electric system more efficiently, whereas consumers or generators that underutilize the electric distribution will have a low load ...
Most forms of uninterruptible power supply (UPS) can be either powered by battery or flywheel energy. These are ready for immediate use at the instant that the mains electricity fails, but the relatively small and finite amount of stored energy they contain makes them suitable for short periods of use, typically in the order of a few dozen minutes to a couple of hours depending on the actual load.
A common prefixed derived unit is "kilovolt-ampere" (symbol kVA). The VA rating is limited by the maximum permissible current, and the watt rating by the power-handling capacity of the device. When a UPS powers equipment which presents a reactive load with a low power factor, neither limit may safely be exceeded. [4]
Full Load hour is a measure of the degree of utilisation of a technical system. [1] [2] [3] Full load hours refer to the time for which a plant would have to be operated at nominal power in order to convert the same amount of electrical work as the plant has actually converted within a defined period of time, during which breaks in operation or partial load operation can also occur.
A plant can also have its output curtailed or intentionally left idle because the electricity is not needed or because the price of electricity is too low to make production economical. This accounts for most of the unused capacity of peaking power plants and load following power plants. Peaking plants may operate for only a few hours per year ...
The energy efficiency of a fuel cell is generally between 40 and 60%; however, if waste heat is captured in a cogeneration scheme, efficiencies of up to 85% can be obtained. [24] World average fossil fuel electricity generation power plant as of 2008 [25] Chemical to electrical Gross output 39%, Net output 33% Electricity storage: Lithium-ion ...