Data CSV Download
I think this will be very useful for many people that want to analyse their data, but I have found that using readings any less granular then half hour is quite inaccurate. I tried the daily download and if I total the values for this year it produces totals about 2.6% higher than the actual values, for both gas and electricity; I can inly assume this is a rounding error.
Another issue is you can't pick a start date, it is always the when the smart meter is active, so you can't get a full year necessarily.
I have my own app that uses the API and can download the values and it is accurate