I don't think "it's a rounding error" is enough analysis here. A couple of meters of sea level rise, a couple of degrees temperature rise; these could be termed rounding errors.
Not degrees, thousandths of a degree, so possibly something like a centimeter if sea level rise.
Considering nuclear and fossil fuels directly release stored energy and solar increase albido this isn’t a 1:1 increase in energy. Further the earth radiates more energy from hot places than cool, still you can approximate it as something like:
Black body radiation is temperature in kelvin to the 4th power. (285 * (170,017^0.25 / 170,000^0.25) - 285) is an increase of ~0.007 C / (whatever our current percentage of energy from fossil fuels, nuclear, or solar).
