Home electricity usage monitors

So our electric company recently offered us a new tariff that gives both cheaper electricity and a monitor that tracks our usage of electricity.  In this case the monitor is an Onzo.  We have had this in place now for just over a week.

First impressions?  Sounds like a great idea.  I had visions of being able to download the data to the computer and analysing it compared to what we are generating and when.  No such luck for two reasons.

Firstly it seems that all of these home monitors only measure the flow of electricity not the direction of the flow.  This is important for those involved in micro-generation (i.e. generating their own electricity) because all of the electricity which we don't use gets exported to the power grid - through the same cables that feed us power.  So the monitor adds up all the power coming in and going out and presents it as a single value.  Which isn't really helpful at all.  :(

Secondly, and this is specific to the Onzo, the 'download to computer' bit they promise is actually uploading to a website (in our case a website specific to our electric company).  So I don't get the raw data and I have to rely on the analysis tools that they provide.  This also means that I can't try and derive, from the combination of the data from the Onzo and from the inverter, what our electricity usage is.

Overall I like the idea of having detailed information about how much electricity we are using and when.  I think it would be highly useful in managing, preferably downward, our usage.  That said I am not at all in favour of devices that only allow analysis by uploading the information to a website.  While I'm not against such things I do prefer to have the option of doing the analysis myself - I want the raw data.

It also seems strange, to me at least, that a whole category of people (those into micro-generation) who are likely to be interested in managing their energy usage are unable to use these devices.

So my recommendation?  If you want to know what you use and when, and you don't do micro-generation, then get one of these monitors (your power company may well supply them for free if you ask).  But either way don't buy an ONZO.  Even free I feel it is a waste.  I can't even give the thing away because they tie it to your persona account at power company thus anyone else using it would find the data uploaded to my account.  :(