A Year of PV

(click to get data)For a full year (1-Mar-2012 to 28-Feb-2013) I’ve been using AlertMe to log the following data for my house (UK postcode CB22), and I’m now making that data available with 5-minute granularity.The above picture shows three quantities:

1) GENERATED: How much electricity is generated by the solar panels
2) CONSUMED: How much electricity the house is consuming
From these figures we work out another 5-minute reading:
3) IMPORTED: Calculated from the above two, how much electricity is being imported
[Note: It is not quite true that 2-1=3 because (like the utility’s electricity meter) we only count 3 when it is positive. So in any given 5 minute period when excess electricity is spilling to the grid, it is ignored from 3]
In the summary picture above, each of these is summed to give the total number of units (kWh) generated, consumed and imported in each month:

I’m making the granular 5-minute data available HERE, since there are many interesting questions that can only be answered with this level of granularity – for example “How much storage would be economic to add?”.

As an example of ways to represent this data, here is the same data with every single of the 250,000 or so datapoints plotted. For the Linear plots, each day runs left to right (00:00 to 23:59) and the year runs top to bottom (January 1 to December 31). For the Clock plots, each day is plotted as a 24-hour clock going from 00:00 at North, round to 06:00 at East, and so on back up to midnight at North, and with the Year running out from the inside of the clock (January) to the outside (December).


Generation (Linear)

Annual Generation (Linear)

Consumption (Linear)

Annual Consumption (Linear)

Generation (24hr clock)

Annual Generation (as 24hr clock)

Consumption (24hr clock)

Annual Consumption (as 24 hr clock)

One can see quite clearly how our household kicks-off at 6am (due East on the 24-hour clock) every morning, the annual cycle of day-length, and the huge difference between a sunny day, a day with scattered clouds, and an overcast day.

Do let me know if you find it useful.

See also my original post From Consumer to Producer showing my PV installation.

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