The plan for PFCs is to scatter factories across Mars, each one with the power of a large nuclear plant. They could each process tons of regolith into PFCs. James Lovelock, a British atmospheric scientist, was the first to suggest the use of PFCs. The super-greenhouse gases trap solar energy so well that they are causing global warming on Earth.
The use of PFCs has many positive qualities such as they are 100 % environmentally friendly, chlorine-free with no toxins, easy to make, produced using molecules of carbon, sulphur, and fluorine, which are all abundant on Mars, and they are relatively inexpensive.
Building space mirrors or using nuclear weapons to melt the southern cap would cost billion of dollars. Sunlight is free and generates more energy in 30 minutes than if all the nuclear warheads in existence exploded at once. Therefore, the use of PFCs is the best option for terraforming.
The gases must be manufactured from materials on the planet and super-greenhouse gases could easily be sent to Mars on unmanned missions annually to begin pumping PFCs from the regolith. The only drawback is that McKay suggests the entire PFC process could take 100 years before average global temperatures reach an Earthly level. After a temperature rise of a few degrees Celsius, gas producing bacteria could be released planet-wide to accelerate the process.