They only started installing 15-minute capable meters in this area last month, and I should be getting one myself within a couple of months. If it were active, the grid company’s service should show 4 bars/readings per hour instead of just one 
. And at least customer service didn’t mention anything about it being in use already.
Edit: Apparently 15-minute net metering had been implemented; it turned out from Datahub, not from their own service or customer service.
Are there any “DIY” electricians here?
I need to replace one panel in a panel string.
Isn’t it so that I first turn the DC isolator switch to zero (OFF)?
Then just take the panel off, open the connectors, put an intact panel in its place, and plug the wires in.
It shouldn’t matter if the sun is shining at the time, right?
Then just turn the DC switch next to the inverter back to the ON position?
I would personally also disconnect both cables from the inverter. Note: After turning off the DC switch. After this, replace the panel.
Especially in the case of an inverter where the string cables are connected via screw terminals (e.g., Fronius), it is important to remember that once the new panel is in place, there is voltage between the cable ends coming to the inverter, regardless of the position of the safety switch. If the system has a separate DC safety switch in addition to the inverter’s own safety switch, this is the case regardless of the system configuration.
If an arc is ignited between these cables coming from the panel string, it cannot be extinguished by any switch; it will only go out when the cable ends are far enough apart or the solar panels stop producing electricity.
If you want extra safety in addition to the switches, one option is to perform the installation in the dark using a headlamp.
And before turning the DC switch, you should generally follow the instructions: shut down the inverter, open the AC circuit breaker, and wait a few minutes.
The new panel should be the same as the old ones, or you should otherwise ensure that it is sufficiently similar.
I added a bit of extra production for snowy conditions as an experiment using wall panels.
In both sets, there is a slight turn towards the optimal direction – they are also positioned away from yard activities, in case they aren’t that easy on the eye:
-2x 405Wp panels with Hoymiles 800W WLAN microinverter to the south
-2x 405Wp panels with Hoymiles 800W WLAN microinverter to the southwest
A separate DTU unit was not required.
Installed price approximately 0.7 EUR/W.
These solar panel discussions reminded me that I’ve planned to install vertical bifacial solar panels at my wife’s house to steer production as early as possible in the spring and late into the autumn, and it’s also the easiest solution for maintenance. In theory, I suppose large solar power plants could be partially designed in the same way. Apparently, the problem arises in positioning the panel fields so they don’t shade each other; the field would probably need to rise upwards in steps or there would need to be a steep slope where the panel rows could be installed at a 90-degree angle. This would automatically shift the yield better towards those times when more electricity is needed, and the summer yield would decrease. I can’t evaluate whether that would be profitable, but I suppose the better prices would compensate since more electricity would be produced during expensive times. There has been quite little discussion about such an alternative for large solar plants in Finland.
Whoops, I only got as far as the Iltasanomat pages, and the topic of bifacial solar panels and vertical installation was touched upon.
Even though the stock market is lagging, it’s nice to follow the surplus production from the panels when consumption is low and most of the solar power goes to sale. For a few days, I’ve heated water with immersion heaters since the credit price was so low. Every day, “dividends” slowly trickle in from that sun up there; it looks like the best hour today will be 20 cents/kWh tax-free. On sunny days, the panels pump out well over 30 kWh a day, while consumption averages 2.5–5 kWh/day. The average price for the electricity being sold is quite decent, and my bills will be in the negative until at least next January. On this side of things, a negative balance is a good thing, unlike with stocks.
we’ve had such miserable and cold weather here in South Savo that it has barely squeezed out enough production for daytime self-consumption… but now it looks like the weather will be improving going forward
Edit: we really don’t get anywhere near those kinds of consumption figures… rarely even in the summer.
If the weather isn’t right next week either, then dividends most likely will be:
Looks like sunshine for at least part of the week, which means rising dividends are on the way. Last week’s consumption was 26 kWh and production from the panels was 154 kWh, even though it has been gray at times. The main thing is that there is at least something positive in this bleak spring.
Your consumption is really impressive. In my case, I wouldn’t even get a week’s worth of hot water with that 
It has certainly been a poor April, at least in Pirkanmaa, compared to even last year. Last year, the yield was 1480 kWh. This year, it will barely reach 800 kWh even though the number of panels is 20% higher.
Almost the entire spring has been like watching the Helsinki stock market 
I’ve also nearly doubled my capacity, so it’s cold comfort. But on the positive side, there’s been yield for every day this spring, thanks to the 80-cubic-meter brushwood project and the vertical panels presented above.
If the DC side has its own safety switch, it doesn’t really serve any purpose if you truly mean that there would still be voltage at the ends of the cables. There certainly won’t be if the connections are made correctly; many people install that DC safety switch even though the standard doesn’t require it if the inverter’s (inu) switch is sufficient.
I’ve been wondering about this:
Does anyone have any idea over what angle a solar panel “captures” solar energy efficiently?
If the sun shines perpendicularly to the panel, the angle of incidence = 0°.
Is over 95% of the maximum energy captured within a -15° … +15° sector, or perhaps even a -30° … +30° sector?
Is there a specific metric for this in the technical specifications of the panels?
I’m also wondering whether it’s sensible to build a curved panel array (southeast…southwest) or have them all in a straight line facing exactly south.
That won’t work with a so-called string inverter, meaning it requires multi-channel micro-inverter(s). You should check your daily consumption profile and orient them accordingly. Few of us are home between 11:00 and 13:00 to consume, for example, a 10 kWp peak from a southern orientation.
Do you know why it’s not possible?
That would mean the inverter also doesn’t tolerate a situation where tree foliage shades some of the panels while others are in unshaded sunlight.
If I understood correctly what you meant.
My idea was that the power output would be distributed more evenly throughout the day.
Does the solar array really need to receive the same intensity of sunlight across all panels?
I meant a curved panel installation like this:
The DC safety switch protects against arcing and electric shock if only one cable is disconnected/cut. If both the + and - cables are cut/disconnected, there is voltage between them.
In the section between the switch and the inverter, there is no voltage between the cables either.
Getting the voltage off the panels isn’t actually that easy. But I believe you wrote that there would be voltage in the cables at the inverter end regardless of the safety switch position; there shouldn’t be any voltage there if the safety switch is in the 0 position.