Talking about electricity consumed by a computer, an old question comes to mind regarding the download of illegal material from Emule, Torrent and company, leaving a PC running all night. On that occasion there were those (an exponent of the current Parliament) asserted that they would spend less if they save energy and buy the original CDs.
Beyond this pretentious and instrumental controversy, it is certainly important to calculate how much electricity a computer consumes per day and how much it costs on the electricity bill .
Monitoring and controlling the energy consumption of a PC or laptop can be useful not only to reduce the final cost of the energy bill and save money but also to increase the life of a laptop battery .
Do not overlook the fact that, by consuming less, you burn less CO2 and reduce the impact on the environment.
The control of how much electricity a computer consumes can be done for free with a calculator and software.
I had already written about how to save energy on Windows and consume less electricity but this time we make a precise calculation.
First you need to calculate the total power (in kilowatts) that is consumed by the monitor, the CPU, the graphics card and other computer components.
You don't need to do these calculations manually, just download and install the free Microsoft program, JouleMeter, on your computer.
This small tool for Windows, which works in the background, can make a precise estimate of the computer's energy consumption by basing its calculations on the processor power, the fan speed, the use of the hard disk, the brightness of the screen and other things .
After a typical day of computer use, it will be possible to check the average consumption (Average) and the total consumption of Kilowatts during the period.
To calculate the cost of electricity (commonly known as unit price or price per kWh) you can consult your electricity bill and check or calculate with the calculator, the cost per unit of electricity .
This unit cost should also be present on the Enel, Acea or other electricity and light distribution companies sites.
Multiplying the unit price per Kwh by the average computer consumption, you should get a rough idea of how much it costs to keep the PC on the electricity bill.
The calculation is approximate because it does not consider the power consumed by other objects connected to the computer such as the modem, router, printer and other devices with separate electrical outlet.
On this, you can deepen the discussion in the technical post on how much a PC consumes and how much energy it needs .
For example, supposing that the computer monitor has a power of 50W, it can be said that it consumes 50 × 1/1000, that is 0.05 kWh of energy if you use the monitor for an hour.
If the price of electricity was 10 euro cents per unit, the total cost of the monitor switched on would have to be 8 x 10 x 0.05 or 4 cents, for an average working day of eight hours.
The monitor is only one of the components of the computer, it is in fact possible to calculate with Joulemeter also the general consumption of the pc, hard disk and processor.
I don't think Joulemter's calculation is as precise as what you would do with an electricity meter such as WattsUp but it remains a great free way to get an idea and a reliable estimate.
In another article, I remember how to optimize the laptop battery and increase its life.
