Recommendation for UK Energy Consumption Recorder

I want to monitor a few devices (standard three pin plugs) to see how much power they are using and when. I have Zigbee and Z Wave devices so not too limited but I just want something that will give me a picture of usage in HA.

Not too fussed about other features like a smart switch or anything just want something to record power usage. This is also only a short term thing so needs to be reasonably cheap.

Any recommendations?