Tuesday 31 January 2012

Snow Clouds Worst Day for Solar PV Generation

We've had our worst day so far for our solar panels generating electricity. It looks like solar PV Generation is very badly affected by snow clouds even if it isn't snowing!

The worst day for solar PV generation so far meant that we only generated 0.2kWh today, a mere fraction of other cloudy days and a miniscule percentage of a sunny day.

Solar PV electricity generation on snowy/cloudy days

It appears that the very dense clouds that bring snow also shield a lot of the solar radiation meaning that the panels produce very little electricity in such dark conditions. Even at peak generating time today between 1200 and 1400 we had over an hour with 0 kW produced which is the first day this has happened since installation.

Thursday 26 January 2012

Mixed Weather but Highest Peak Output So Far

Today we have achieved our highest peak output since installation in Nov 2011. At 1330 today our 14 solar PV panels rated at 3.01kWp were generating 2388W of electricity which is nearly 80% of their possible output.

Let's hope that the summer brings even higher peaks of generation!

Peak output values for solar pv panels

Solar PV Appeal - Boom & Bust then Boom and Bust All Over Again

After the High Court decision yesterday to reject the Government appeal over their cuts to the Solar Feed In Tariffs it looks like the solar industry in the UK will be back on the rollercoaster of boom and bust that started in October 2011 with the initial announcement of the cut from 43.3p to 21p per kWh generated.

The number of installations between 31 October and the FITs cut on 12 December showed a massive spike with installers scrabbling to get any available supplies to be able to fit before the deadline. This was then followed by a complete drying up of work as the new tariff took effect.

With the new deadline set for 3 March it looks like the same process is happening all over again with reports that warehouses of Solar PV panels have been bought up and installers reporting lack of supplies to be able to install.

Gordon Brown might have claimed he had ended boom and bust but this government seems fairly unique in being able to create boom and bust twice within the space of 4 months!

Saturday 14 January 2012

200kWh Exceeded and Best day for generation so far

So today we have seen the 200kWh barrier passed and also with a glorious sunny day from sunrise we have set a new record for the generation.

It shows how insignificant the winter months generation are when it has taken nearly 2 months to reach our first 200kWh of PV solar generation when in the summer this could be more than achieved in a couple of good weeks.

Today we have generated 8.8kWh of electricity. Compared to the summer it isn't a huge amount but for winter is a result that we are very pleased with. The forecast for tomorrow is equally good so hopefully we may get an even better output tomorrow with the marginally longer day.

Monday 2 January 2012

Viewing Your Solar Panel Data Without Sunny Webbox. View Sunny Explorer Online

How to View Your PV Solar Panel Data output without an SMA Sunny Webbox? View Sunny Explorer Data Online

The SMA Sunny Webbox gives a very good way to view your solar panel electricity production data remotely but is a very expensive solution at around £400. The SMA Sunny Webbox gives you an IP address that constantly publishes your solar generation data to the internet so that you can view from anywhere.

UPDATE - see feedback below from Nick, since this post I am now using sma-uploader to automatically load my live and historic data from my Sunny Boy inverter to PVOoutput

There is an alternative way to view Sunny Explorer data online if you have some time to set it up. Although it is more clunky than the Sunny Webbox it is free and will save you the cost of buying the Webbox. This only works for SMA Sunny Boy inverters - ours is a 3000HF but I believe it will also work with the TL series such as 4000TL as well.

The essence of this solution is that you run the Sunny Explorer software on a laptop which connects to the SMA Sunny Boy 3000HF (or 2000/2500HF or 4000TL) inverters and is running during the day only using the Sunny Explorer software. The screen capture software takes a screen shot of the Sunny Explorer output every 2 minutes and saves a copy as a JPG or PNG file on your laptop.

The FTP batch file copies the screen image to your webserver where it can be viewed from anywhere in the world with an internet connection.

You can see an example of the output from this method here


What you will need:

1) Web hosting space and a domain (I already have this for other websites so no additional cost)

2) A PC or laptop that has bluetooth and can connect to the Sunny Boy Inverter using Sunny Explorer software

3) A small screen capture programme, I've used Auto Screen Capture which produces an example file as below

Sunny Webbox Alternative

4) An FTP batch file to copy the screen capture images. This link explains how to setup the FTP batch file

An alternative that I have considered is making use of the Command Line batch processing facility within Sunny Explorer to export the daily generation data to a folder on my server. This folder is replicated