Most of e.g. Germany's gas consumption is from heating, not electricity. So nuclear plays a minor role, though admittedly even needing just 10% less gas might be the difference of being able to procure what you need from non-Russian suppliers or rationing. (Sure, heating and electricity is kind of equivalent if many households had heat pumps, but they don't.)
Nuclear or not, the horrendous mistake was not reducing dependence on Russian exports even when their aggressive foreign policy was apparent even 10 years ago. That was inexcusible complacency.
Why is this the case? The only reason I could think is electricity prices. Here in Montreal where the average low for today is -11oC and electricity is very cheap, nearly everyone uses electric baseboards or electric boilers.
I'd imagine Germans would be quick to install electric heating if electricity was cheap, no?
Wouldn't expanding nuclear drive down electricity prices?
I don't know why gas heating is so prevalent in parts of Europe historically, I guess fossil fuels were just the cheapest way of heating compared to electricity. Google says that in Canada also much heating is gas or oil based, so perhaps the prevalence of electric heating is a feature of your particular residential area?
In any case, I think electric heating will become much more prevalent anyway since it's necessary for the clean energy transition. But that will take far longer than the current Russia crisis, so it's unfortunately no short term fix.
You've got loads of hydroelectricity in Québec, that's fairly cheap. In Europe most of the electricity was (and still is) generated with fossil fuel so if you are going to heat a place, you might as well use the gas directly, that's more efficient.
There are a few special cases though: if you go in southern Europe, especially in Greek islands, you will find a lot of solar water heating. And France has a higher than average electric heating due to its nuclear grid.
Is not that the nord stream 2 pipeline? Germany was able to buy Russian gas without problem. Why build the new pipe?
It seems that Germany thought that Russia was a rational player interested in growing their economy, but it seems that it was just power play for personal aspirations.
Nuclear or not, the horrendous mistake was not reducing dependence on Russian exports even when their aggressive foreign policy was apparent even 10 years ago. That was inexcusible complacency.