Apple has quietly released a battery charger - and I must admit that I did not realise it was something special until I read the following :

The specs are what make this thing particularly interesting for low-power battery-powered devices:
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The charting of electricity usage are improving as my understanding of highcharts is improving - and they now look better

(Click for larger)

It is of course difficult to use the dynamic zoom features in a static image as the one I have embedded here (-; .

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My first try at generating nice javascript graphs (using highcharts) from the Wattson electricity consumption meter :

nb! All text x-axis text is wrong, and the header text is wrong as well. (Did I mention that this was my first try)

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The software measure our gas usage in the house is coming along slowly - I have attached a LDR to one of the Jeenodes and found out the light level when just the pilot light is on, and the light level when the burner is on.

so I can now detect the transitions when the boiler turns on and when it turns off, and from there calculate how long it was turned on for.

This all looks a bit strange at the moment :

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For our home monitoring system I have long had a problem -

- We do measure the amount of electricity we use, and plot/graph this quite accurately

- We do use gas for heating (2 boilers) plus a hob in the kitchen.

Measuring usage of gas seems to be difficult with any easily accessible technology, and the very oldfashioned meter we have for the house will not work with any of the methods I have seen so far - as we do not have either a flashing led nor a rotating disc.

So while trying to think through this I came to the following conclusion :

- The gas usage for the hob is probably little compared to the boilers, and there is very little we can do to reduce it, therefore I will concentrate on the usage by the boilers.
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