Power Unit

What are units of power? Although this question might appear rather straightforward at first glance, a power unit actually represents somewhat of a complicated concept. From a scientific point of view, a power unit is defined as how much work is accomplished during a specific time frame. There are also instances when this term can be used to describe how quickly heat or electrical energy is transferred between two different locations.^[1]

The main intention of a power unit is to allow individuals (such as scientists and engineers) to quantify how an electrical or mechanical system is operating. Common examples include stationary surveillance networks, measurement technology, backup batteries, hydraulics, and commonplace concerns such as how much electrical power a home consumes per month. By appreciating these metrics, it will be much easier to address issues such as efficiency, safety and reliability.

What is Meant by the Term "Power Unit"?

To clarify the previous section, a unit of power can be described by the formula P=W/T. P is an abbreviation for power, W signifies work and T equates to time. In other words, a power unit is defined as work divided by time. If we happen to be discussing electric power units, the formula P=VI can be used. In this case, a power unit is the product of voltage and current (measured in watts).^[2]

A final point should be mentioned before moving on. The exact way in which a power unit will be measured also depends on whether we utilise the metric or imperial system. Metric systems employ watts while imperial measurements will instead opt for terms such as foot-pounds per second or horsepower. For the sake of simplicity, we’ll try to avoid this nomenclature when possible.

What is the Difference Between Work and Power?

This is yet another question that appears deceptively simple., After all, we tend to use these two terms interchangeably. Things are much different from a more technical point of view.

Work is defined as the amount of force needed to move an object a predefined distance. A power unit is instead concerned with the rate at which the work itself is accomplished. As you might have imagined, joules are the units employed to describe work (as opposed to the watt instead associated with power itself).^[2]

We should finally clarify the difference between energy and power. Energy is used to describe the amount of work that can be accomplished by a specific force. On the other hand, a power unit involves how quickly the rate is at which the work is carried out.^[3]

What Types of Units of Power Exist?

Now that we have obtained a basic understanding of a unit of power, are there any types that can be used to address specific situations? For the sake of this article, we will examine three power unit variants.

A Look at Electrical Power Units

As highlighted above, a single unit of electric power is a watt. A watt is defined as one ampere of energy being driven (under pressure) by one volt.^[4] The watt was created to honour James Watt (the inventor of the steam engine). Once again, this power unit can be stated as P=VI. We should also note that one watt is a relatively weak source of power. This is why modern applications will often refer to multiples such as kilowatts (kW), megawatts (MW) or even gigawatts (GW); particularly when referring to larger systems such as electrical energy grids. This type of power unit is relevant to many of the products engineered by the team at EFOY Pro.

What is a Mechanical Power Unit?

What about a mechanical power unit? In this case, joules, horsepower and watts can all be used as a power unit. However, joules and horsepower tend to be more common. Once again, a mechanical power unit is used to describe the amount of time required to complete work.^[5] Let’s take a look at a few typical examples to clarify this point.

• The amount of horsepower produced by a car’s engine.
• The heat produced by a power plant used to turn a turbine.
• A crane using mechanical power to lift a heavy object.

A mechanical unit for power can be employed to illustrate how much energy is required to complete each of these tasks.

Hydraulic Power Units

When referring to hydraulic systems, watts tend to be the preferred power unit. However, determining the output is slightly different. This is accomplished with the formula P=Q x P. In this case, P represents the power in watts, Q is the flow rate (litres per minute) and the second P indicates pressure (in bars). Some systems where this type of power unit can be applied include:

• Hydraulic jacks and lifts.
• The landing gear of an aeroplane.
• The steering within a typical car.
• Shock absorbers often present within heavy equipment.

Hydraulics have become extremely commonplace due to the fact that they can address demanding workloads, they are relatively easy to maintain and they can provide a constant force.^[6]

Power Supply Units: Adapting to Modern Technological Innovations

Although a power measurement unit might appear to be nothing more than an academic principle at first glance, there are literally thousands of real-world applications related to a power unit. For example, the fuel cells and batteries offered by EFOY Pro can be used within off grid power systems or as a redundant component within an uninterruptible power supply.

The Humble Power Unit

Ultimately, any power unit represents the building block of many technological innovations that we have come to rely upon in these modern times. From being used to determine how much electrical energy will be required to power a remote network of cameras to calculating if a crane is capable of lifting a bulky load, the applications of a power unit are virtually limitless. We should nonetheless keep in mind that this article only scratched the proverbial surface in terms of why a power unit is so important.

Power units are also indispensable for our EFOY products. Do you have any questions about the products and services offered by EFOY Pro? If so, please take a moment to contact one of our customer service specialists.