Electricity usage monitor

[acewoodturner]

I n a small business of which part of is milling my own timber and kiln drying it in an electricity powered kiln. I would like to monitor the amount of electricity the dehumidifier uses so I can work out a cost per cubic foot to dry it. I cant just multiply the rating of the dehumidifier by the number of hours its on as I have to increase and decrease the level it is set to. The difficulty is that I have the lights and other machinery on in the workshop so its not just a case of taking a meter reading.
Are there gadgets out there which I can plug the dehumidifier into and then plug that into the mains socket which will record the usage?

 

[AllUpHere]

Something like this any good?
http://www.maplin.co.uk/p/13a-plug-in-energy-saving-monitor-n67fu

 

[acewoodturner]

Brilliant, that is exactly what I am after, thank you