Two years with solar panels

Two years ago today, my eight photovoltaic panels were connected to the grid, and I could benefit from electricity generated in my own garden. How has it worked over two years? (Incidentally, yesterday evening's deluge gave the panels a thorough cleansing.)

Well, experience now shows that I should have installed more capacity, as the eight panels only managed to generate 78% of the electrical power that I have used over the past 12 months. Having said that, through better management of my electricity use, that's gone up from 72% over the previous 12 month period (12 July 2022 to 11 July 2023). 

The output of my panels – something entirely out of my control – was  up by 3% over the same period a year earlier, and my energy-saving efforts mean I used 16% less power. (Hurrah! Three percent more sunlight over the past year!)

But could I squeeze any more savings? Not without discomfort. In winter, the house is kept heated to 21C when I'm in and 17C when I'm out (to keep mildew and damp at bay). I confess to having inadvertently left the immersion heater switched on a few times overnight, and not defrosting the fridge often enough. Otherwise, I struggle to see how I could use less prąd – a nice, short Polish word, proving that not all Polish word are longer than the English equivalent. (Indeed, why not take 'prond' as a loan-work for electricity – one syllable for five?)

My energy bills (paid every six months) are low; in February I paid 385 złotys (£77) for all the electricity consumed from 12 July to 12 January. This works out at around 65 złotys (£13) a month averaged out across the year. Without the panels, I would have paid 1,136 złotys for six months (£227) or 189 złotys (£38) a month. Connection charges and other fees in this incredibly opaque bill push up the ratio, but in general, the bills are two-thirds lower than they would have been without the panels.

So – was it worth it? I have the spare cash, so yes it was. The payback period for the panels – which the salesman worked out to be eight years – turns out to be nearer to 14 years (at current prices). This is not the really the point. Poland still generates 61% of its electrical power through the burning of coal (both bituminous coal and lignite – that horrible low-grade brown stuff). This is down from 70% in 2020. Much of the rest comes from natural gas, no longer from Russia. The less of those fossil fuels I use the better. Of course, what I generate and sell to the grid in summer from my panels I draw back from the grid in winter, generated by fossil fuels, but while the sun shines – make hay.

This time last year:
Michalczew, south of Krężel

This time three years ago:
High summer in Chynów: storms, fruit and exercise

This time four years ago:
Summer wet and dry

This time six years ago:

Rainy summer Warsaw moods

This time eight years ago:
Marathon stroll along the Vistula

This time ten years ago:
Complaining about the lack of a river crossing between Siekierki and Góra Kalwaria! 

This time 11 years ago:
S2 update 

This time 12 years ago:
Progress on S2 bypass – photos from the air

This time 14 years ago:
Up Śnieżnica

This time 16 years ago:
July continues glum (16 years on and a week of 30+C heat)