One year ago, I embarked on a mission to fully appreciate the realities of solar PV and how the technology fairs out in Ireland. After weighing up various options I ended up settling to go for a ground mounted array in the back garden south facing without utilizing SEAI grants aid. Why? The build and installation of a somewhat direct labor effort was 60% of the lowest roof top grant aided equivalent price (and I do love a challenge) Six months later (a credit to my lovely wife's patience) I had my very own small scale solar PV farm!
I quickly implemented monitoring using our DCSix Wattric solution and have been recording 5 second data on generation since.
So what has happened?
In the past six months:
1. The PV has generated 920kWh of Green Energy, of this 920kWh
2. My 2.5kW "peak" system has peaked at 1.9kW (wierd that eh?)
3. I have spilled 450kWh of electricity out to my neighbours and community
4. I have imported 1450kWh from the grid in this timeframe
Talking €€€ to date, The PV system has offset €85 from my electricity bill and has allowed me to feel good about exporting the same amount again onto the grid.
And from a sustainability perspective I have saved over 700kg of Co2e (over 5000 km of equivalent driving)
My initial thoughts on solar PV:
During the sunny month of august i thought "this is the way of the future for generation in Ireland"
It is… when the skies are blue, the voltage on the network is correct and the skies are really really REALLY blue. below is a graph of generation on a blue-sky day on September 14th.
Doesn’t it look perfect? Now lets look at the very next day:
Not so nice.... No surprises here but light cloud cover dramatically affects the generation profile on a second by second basis on any given day. Surprisingly light rain does not adversely effect the output.
Does this pay back?
Currently it would take 20 years to pay back for an SEAI approved install assuming no failure of any component in the system, however by adding a €200 solar diverter for hot water it allows you to half the payback period.
A DIY and direct labour system such as mine has roughly half the cost and therefore half the payback.... hopefully :).
Weather permitting it should provide a yearly capacity factor of 12%. So far through the autumn and winter period it has managed to hit 11.95% leaving me optimistic it may hit 13% given we are in the south of Ireland that is very impressive!
Would I do it again?
Yes, but I would have opted for a smaller system to cover the base load of my house
Is it all about the money?
Definitely not but one has to think that if we are to efficiently chase decarbonisation at an Irish level. Is there a more efficient, cost effective way for me to invest in low cabon living and measures to save in the order of 1.2TCo2e per annum for a fraction of the cost. community schemes for wind or solar? carbon investment banks? renting meadow land? more to come in next weeks agri post
Having said this if it balances the equivalent of someone driving 10,000km every year then i am all for it.
How can i best decide on my options?
None of my calculations or validation would have been possible without first knowing my existing energy footprint. Monitoring and visualisation of energy consumption was key here and was easily accomplished using Wattrics from DCSix