This surprised me! So I Googled it. Is this your source? It is Wikipedia's source. Who are the 440 people dying per trillion kWh of rooftop solar? (note: this is rooftop solar; utility solar statistics aren't included in the below source)
[0]: https://www.forbes.com/sites/jamesconca/2012/06/10/energys-d...
[1]: https://en.wikipedia.org/wiki/Energy_accidents#Fatalities
There wasn't even a single tkWh of power produced by rooftop solar in 2012. The total solar (rooftop, commercial, and thermal) energy produced in the US in 2012 was 4,327 million kWh... or half a percent of 1 tkWh... making me think that the 'deathprint' of 440 deaths per tkWh for rooftop solar in 2012 was extrapolated by taking the number of people who slipped and fell off a roof and multiplying it by 200. My guess, based on the expression "Mortality Rate (deaths/trillionkWhr)", and the fact that less than 4.3 billion kWh of solar energy was produced in 2012 by rooftop solar (Wiki doesn't break out production by method), is that approximately two people have died in the quest for solar energy.
[2]: https://en.wikipedia.org/wiki/Solar_power_in_the_United_Stat...
Further - it is too soon to tell what the 'deathprint' for any given kWh of nuclear energy is. The method of production could kill someone for some time after the kWh is consumed.