All hail solar panels

I have chosen to avoid politics in my posts, but this gets fairly close. So please, before proceeding, take a deep breath and consider the numbers mentioned before getting angry.

It seems that renewable energy sources - especially wind and solar - are all the rage these days. While in some locations it makes kinda sorta sense, from my perspective the problem is that I live at fairly northern location - namely Finland, and where I exactly am the annual average temperature is slightly less than three degrees Centigrade (around 39F). Northern location also means that temperature varies wildly over the years (lowest daily average being around -10 degrees C, and lowest winter temperature often is -30 .. -40 C range), as well does the solar insolation.

Just for the fun of it I did the math on how much solar panels would be needed to cover electrocity usage of Finland with solar only. Sorry I'm not giving the worksheet, it's really messy, but the numbers I'm basing this are following (and should be easily found with some seaches, albeit the document I took electricity figues from is in Finnish only - I'm sure equivalent info is available).

Number of households: 2 532 000 (note that this includes everything from 1-room apartments to huge mansions)

Winter-time panel energy, optimized for winter production (ie 60 degree tilt): 0,86 kWh/m2/day.

Average maximum power usage in winter: 13000MW (approximate, there is variance from 11000MW to 14000MW over typical day). Of this, renewables (mostly water power) cover currently about 2500MW, leaving about 10500MW for imported electricity and non-renewables. So let's use that as base for calculations.

Extending that average usage over day, divided by production, says that we will need approximately 293023255 square meters, 293 square kilometres, or 114,5 square miles of panels to cover that usage. That is pretty frickin' huge land area!

Again, dividing that by number of households means that every single household would need about 115 square meters (very roughly 1150 sq ft) of panels if these were installed on roofs. At this point I'd like again to remind that many of those households are in apartments, making it impossible for them to have that large area of panels, and many older (smaller) houses don't even have that much surface area to begin with.

At the moment of writing (late May) the total electricity usage hovers around 8500MW mark (unfortunately I didn't check insolation and I'm being too lazy to search again so I'm taking a guess of 3 kWh/m2/day (summer maximum being 5,3kWh/m2/day) - which would  drop these figures to 48 square kilometes of panels, or about 19 square meters per household. This of course assumes all-solar, that of course is insane goal.

Now moving to next issue: winter is pretty damn dark around here. In january we get some 4 to 6 hours of light, sun being very low at horizon. Not much sunlight to capture there. So let's give a optimistic figure and say that we get whopping 8 hours of usable sunlight a day that produces all the energy we need, and we only have to cover only half of the winter energy usage calculated above with solar (let's say round 5000MW), rest coming from something else (with what is another question but let's just ignore that for now).

So this means that over that 8-hour period we need to store total of 120000000kWh of energy, or 47kWh per household somewhere. That won't be easy either. While Tesla's PowerWall and future iterations may help a bit there, the problem with batteries is that they wear down and when something goes wrong they behave .. well, let's just say unpleasantly. And when dealing amount of batteries needed here and huge amount of charge/discharge cycles, something will go wrong every now and then.

What I'm trying to say: While solar is great (and make no mistake, I love the idea -- I have done the math for my personal use over and over again but the numbers still haven't turned out financially worth it, no matter how I try), there is currently absolutely no way it could be reliably replace even small part of current baseline production. Yet whenever there is news or discussions about solar, these problems are never mentioned, or if they are, no one is willing to answer questions about this - least those who most vocally want to  increase solar usage. Wonder why?

And do note, above I have spoken only of electricity. If you want to get rid of fossil fuels, above numbers don't include oil, LNG and other forms of fossil fuels used for other purposes like cars and airplanes, so you have to add their energy on top too.