owg - the hypothesis is that CO2 is the driver. Unfortunately (for them), the data does not support said hypothesis. However, rather than letting the hypothesis die and having another one take its place (as is the norm in science), they have resorted to moving the goalposts.
See, if it's not CO2, then you can't control people via their energy usage - burning cheap fossil fuels. That won't do for the political overlords that have the "climate scientists[™]" working for them.
Real, truly independent scientists that study the climate acknowledge that humans have an impact: urban heat island effect, local heating of bodies of water near power plants (doesn't need to be fossil-fueled, either), and yes, even CO2. But the magnitude of the CO2-effect is small - certainly not enough to warrant spending Trillions of dollars. And the other effects are very localized - not enough to qualify as world-wide climate.
Which brings up another point. The whole terminology change to "climate change" is another sleight of hand trick. Of course they mean warming. But, from a geological perspective, the only constant in the climate is that it changes. Severely. And frequently. So, can we cause climate change? Possibly, but it has always changed without us, so can any scientist discern the human fingerprint in such a chaotic system? Unlikely with sufficient certainty to warrant us spending Trillions of dollars.
Oh, and if you wanted to, you could consider the entire human energy needs, assume that it is all eventually returned to heat energy, and compare that to the amount of energy we get from the big yellow ball in the sky. OK - here's the calc:
In 2008, worldwide energy usage was 474E18 J.
Total solar irradiance is 1361W/m^2. Divide that value by 4 (ratio of area of a circle vs surface area of a sphere). Total of 680.5 W/m^2.
Total surface area of the earth is 5.1E8 km^2, or 5.1e14m^2.
A standard year is 3.15569E7 seconds.
Multiply solar power by the surface area by the time, and you get 1.095E25J.
So, our energy needs are 474E18/1.095E25 - 4.378E-5 of what we get from the sun. So, nope, it's not the heat that we generate by our energy consumption.
