The layout is designed to minimise shading of the panels by the dormer window which would severely reduce the amount of power generated.
Left to right the new things are a RCD to disconnect the PV system if earth leakage detected; the production meter, which will be used to justify any Renewable Obligation Certificates; the AC isolator. Above these, there's a new circuit breaker on the distribution board for the inverter. And there's gas and water earth-bonding cables in there too because they weren't previously earth-bonded.
After deciding to stick with our existing electricity provider
Atlantic Electric and Gas
(a trading name of the Scottish and Southern Energy Group), they
installed a new meter (for free!) that shows imported and exported power.
So the panel now looks like this:
Chunky aluminium? C-channel screwed and mastic-d onto the tiles.
It was getting dark by the time I got up the scaffolding: I'll try to brighten the pictures sometime.
The panels are clamped onto the channels:
The inverter converts DC electricity from the PV panels to 50Hz AC suitable for connecting to the mains supply. This is a Fronius IG 15 (manufacturer's datasheet).
It sits in the front roof void just below the panels. The cables from the panels come through the roof above the centre of the picture. Right of the actual inverter are: aerial for the wireless display; DC (PV panels) isolator; AC isolator.
Cables left to right: AC, DC x 2, aerial for remote display.
The three empty slots in the inverter can hold circuit boards to enable data logging if I wanted real-time graphs.
8 x Sanyo HI-215NKHE5 (PDF datasheet) each 1570x798x35mm with a maximum power output of 215W, giving a total of 1.72kW possible. Up here at 55°N I will never get the optimal output so I hope these panels will produce about 1,500kWh over a year — about 1/3 of my present annual usage.
The Renewable Obligation Certificate (ROC) meter (PDF datasheet) that records what comes out of the inverter. It showed 1.3kWh soon after startup ... but power had peaked at 180W and shutdown after about 1h30 so there wasn't enough time for 1.3kWh! I'll assume this was from manufacturing/testing.
The wireless 'Personal Display' which shows the same information as the display on the inverter: all the statistics available for now, the day, the week, the year. Bigger than I expected, but saves crawling into the roof void to check the numbers.
