This is the real cause of any so called global warming we have going on. The sun is releasing more thermal energy.
Not quite.
A high level of sunspots indicates a high level of magnetic activity by the sun.
A high level of magnetic activity by the sun shields the Earth from cosmic rays.
Cosmic rays cause water molecules in the atmosphere to clump together, causing more clouds and cooler temperatures; lack of cosmic rays leads to less cloudiness. This has been experimentally demonstrated in laboratories - not computer simulations.
This is the history of temperature - lots of sunspots mean warm and dry, no sunspots mean cloudy/wet. The records over nearly a thousand years show this correlation.