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Unite Legal De L`energie

Also, keep in mind that one watt is worth 1 joule/second, or about 0.239 calories/second. For the specific case of solar energy, we often talk about the watt tip, which refers to the performance of a photovoltaic solar panel in ideal conditions (no shade, good sunshine …). A system with a capacity of 3 kWp will very rarely produce this 3 kW (which does not mean that the panel is inefficient). The legal unit of measurement of energy in France, as in almost every country in the world, is the joule (J). It is part of an overall system called the International System of Units (SI). Strictly speaking, watt (W) is not a measure of energy, but a measure of performance. A watt is the uniform transmission of one joule over one second. For example, a machine with a power of 60 watts can transmit 60 joules in one second or 3600 joules in one minute. A great way to imagine a watt is to imagine a microwave oven.

If you want to transfer less energy to the dish, set it to a lower power, for example, 600 watts, but if you really want to cook the dish with a grill function, you need to exceed 1000 watts. In plain language? Electric current is a displacement of electrons. To make them move, you need an energy generator that creates a charge imbalance (potential difference) to attract and repel electrons. This charge imbalance is called “electric voltage”. Note: The confusion between the term kW and kWh is repeated again and again. The international unit of energy production (kW) is used incorrectly to express consumption or production. We do not consume kW, but kWh. On the electricity bill, consumption is indicated in kWh. It is a commonly used unit in the fields of nutrition and heat. Today, one tonne of coal equivalent is typically worth 29,307 60 GJ or 8,141 MWh. Thanks to a nuclear reactor, 500 kg of uranium produce an energy of 2{,}52 times 10^{14} J.

Convert this energy into tons of oil equivalent. Kilowatts, megawatts, cumacs, peak kilowatts: As energy issues become increasingly important in our daily lives, it is more important than ever to understand the importance of the most commonly used appliances. This discrepancy explains the use of different units. Unfortunately, this often creates confusion about orders of magnitude, which hinders the understanding of phenomena. In order to be able to talk about energy without being weighed down by extended numbers, multiples are used, as for each unit of measurement. We often hear about kilowatts (solar panels on roofs are often between 3 and 9 kW), megawatts (EPR reactors under construction will have a capacity of 1600 MW) or gigawatts (GW). We remember the correspondence between joules (J) and electron-volts (eV): 1 eV = 1{,}6 times 10^{-19} J. In electricity, power = voltage x intensity. If we take the image of a water pipe, the electrical power corresponds to the pressure in the tap with the tap closed (voltage) multiplied by the flow of water with the tap open (intensity). The tonne of coal equivalent (tec) is a unit of measurement specific to coal. It represents the energy contained in one tonne of coal and initially depended on the reference coal. For large amounts of energy, multiples such as kWh (kilowatt hour) or MWh (megawatt hour) are usually used.

The kilowatt-hour (kWh) is a unit of measurement that corresponds to the energy consumed or supplied by an installation in thousands of watts during one hour. The volt reflects the electromotive force and the potential difference (voltage) between two points in a circuit. This unit is often used to describe the amount of heat per unit of time (power) that can be emitted by a heater such as a boiler or a refrigerant such as an air conditioner. Submultiples: kWh, MWh,. are also used. The legal unit of energy is the joule (J). According to the relation “Delta W = P cdot Delta t”, a joule is the energy of a one-watt power system for one second. The kilowatt (kW) or 1,000 watts is generally used to describe the electrical power of electric or thermal motors. There is also the British Thermal Unit per hour (also called the British Thermal Unit per hour, symbolized in both cases by BTU/h), which represents the power of a system delivering or consuming a BTU in one hour (for 1 BTU/h).