After searching the web I found a site called Cost Logistics who are based in the United Kingdom

You can calculate the cost of running your computer with it

The cost of running your Computer and Monitor is based on UK Electricity cost per Kilowatt

You can adjust this figure at the site to coincide with the cost per Kilowatt per hour that you are being charged on your current electricity bill

For other countries, you will have to convert your hourly cost per Kilowatt hour to Stirling and then convert the result back to your Country Currency

A pain, I know, but if you want an accurate cost it may be worth the trouble

It is a very versatile program and lets you input your own parameters

I hope this helps to calculate the cost of running your system

Here is the Link: Electricity Cost Calculator

Regards
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