The Differences Between kVA & kW

Measuring Amperes

• The ampere, or A, is the international standard unit for measurements of electric current. The electric current is a measurement of how much energy potential is produced. When a generator produces electricity, the speed with which it moves will determine the electric current. It is the force by which the electrons are conducting energy. If electricity was a liquid, the ampere would measure the water speed.

Measuring Voltage

• The volt, or V, measures the electric potential. The potential between two electric conductors can be quite high, but the electric current quite low, which means a small release of energy but a high voltage. An example is static electricity. The volt is measured as the electric potential when one ampere of electricity releases one watt per second of energy. If electricity was a liquid, the volt would be the water pressure. Unless you open the tap, there is no energy release, but when you open it, the water starts flowing at a speed that depends on the size of the tap and the pressure in the pipe. That pressure is the potential, until the tap is opened.

Measuring Wattage

• The number of watt, or W, measures the energy produced - the effect. This is not dependent on electricity, but any energy conversion can be measured in watts. Originally, the watt was defined as the work that is needed to keep a mass of one kilogram stable against a force of one newton. But now, it is defined in more abstract terms. When it comes to electricity, one W is the work done when one ampere (A) of current flows through an electrical potential difference of one volt (V). In the liquid example, the watt is the force by which the water comes out of the spout when the tap is opened.

The Difference Between kVA and kW

• Volt and ampere measure the potential energy, and watt measure the work actually performed. So the difference between VA and W is that the VA measures potential, but the W actual work. The k is abbreviation for kilo, which means 1000, so the difference between 1 kVA and 1 kW is the same as between one VA and one W.