A few good days

A few good days of weather and we're back on track. In fact the last two days have been about as good as it gets with 20kWh a day flowing from the panels under clear blue skies. This has improved the generation stats and closed the deficit against the predicted generation levels - hurray. 

Although the weather has been near-perfect, the peak output is not as good as I'd hoped - more in the upper 2 kWhs rather than in the lower 3's. I suspect this might be the slightly hazy nature of the sun, but I cant really complain after all this rain we've had. It's great to see some output.

Overall, the meter under the stairs says 2237kWh to date, which means I've passed the £1000 point since the system was first commissioned. It's taken a little time, but I'm still ahead and it's nice to see the investment starting to pay back. I look forward to submitting my next meter reading in mid-August.

Weather, Owls and Spaniards

So they tell me that the weather is about to get better. Apparently, the run of poor weather we’ve been seeing of late is courtesy of the jet stream being too far south and hence the mixed weather to the north is fairly and squarely ensconced over the UK. The smart people in the met offices of this world now tell us that this is about to move, by the weekend the jet stream will move northwards and the lower part, at least, of the UK will start to see the benefit of improved weather. (This could be a major boon in time for the Olympics which might otherwise have to be held underwater).

You’ll have to pardon my scepticism at this point. It’s not that I don’t believe the science behind weather forecasting, it’s that based on recent experience, and the chaotic nature of weather (that’s chaotic in the mathematical sense) I think I’ll believe it when I see it. It would be nice to think we’ll get a summer at last – which would be handily in time for the school holidays, my solar panels and the contents of my greenhouse. But I hope to be amazed shortly.

The solar PV system is, however, slowly doing its thing and generating power, albeit somewhat slower than you might expect for this time of year. We’ve made it through the equinox, and are on the slow run down to winter (makes me sound like a right pessimist) but with the balance of July and the whole of August to come, one hopes that we might get to see something special at this peak weather time of year.

July so far has been pretty mixed, the odd nicer day mixed in with lots of cloud and many showers. I’ve had a couple of good days (mid teen production) but no wall-to-wall days when the kWh’s really started to flood in. It’s a little disappointing given the day lengths available, but on the other hand I should be pleased that even with these limited days we’re fairly close to the generation prediction. I know I’m running about 10% behind where I should to be, and a lot more behind where I’d like to be, but given the conditions, I still find it amazing that I’m able to generate so much, so easily.

As an update the Owl seems to be behaving itself again. Two problems connecting to the transmitter in three days was a little worrying, but all seems to be good. Talking of the Owl, I see on their website that there is a new gismo (or should that be toy) available that allows automatic transmission of readings to the web for access via iphone apps and the like. I haven’t seen any reviews of this, but I might be tempted to play with this at some point, since it appears that it may be possible to have this as a retro-fit using the existing transmitter. I think I will hold fire until I see some independent reviews.  

In order to share data more effectively, I’ve added some additional ‘pages’ to the blog, these are on an extracted page per month based upon generation stats courtesy of google docs. This was fairly simple once I’d worked out what to do, but it does lack a professional look to it (no colour scheme and no links). However, it is a start, since it appears most browsers are unable to see the java charts on the top and right hand side of the blog. (I’ve still no idea why this happens).

On a completely different tack, I’ve just returned from a couple of days in Barcelona, where the sun shone, the humidity rose and it was all-round too damn hot for my liking.  However, I was surprised not to see a single solar panel all the time I was there. Given the excellent natural climate and strong light I would have expected to see something. From my hotel room window I could look out over a fairly large swathe of residential housing (a good few hundred properties) and there was nothing to behold. Maybe the subsidy is not there, or the planning is too draconian – who knows? I would spend some time investigating if I was really that bothered, but as a point of interest, I would expect some panels to be blasting away given the suitability of the conditions.

Owl on the blink

So for the second time in three days the OWL CM160 unit has stopped recording any power. Thankfully this is not the fault of the system, more an issue with the OWL. 

I've changed the battery in the sender unit, and reestablished the connection, only for it to cut out again a few days later. I shall have to have a go under the stairs again to try and work our what is happening - but without waking everybody up.

I've also noted another potential issue with the unit - it tends to stop recording internally for short periods. It still displays a reading, but sometimes when you come back to it, it does not seem to have advanced as far as one would expect. So on a bright day when it's showing in excess of 2kW you can come back a couple of hours later to kind the cumulative count has not moved as far along as you might think. I thought it was just me, but a recent check of the meter suggests that I'm 40kWh behind what the meter under the stairs says, and that's accumulated over 6-8 weeks since the last time I aligned the readings by hand. I already have an error correction built in to the readings spreadsheet, so I don't think that that's the cause, but I suppose I shouldn't complain too much if the difference is in my favour.

I can feel a replacement unit on the way.