Today the majority of the world's electricity is made with fossil fuels (mainly coal). There are exceptions. France makes most of its electricity with nuclear power. Norway and Brazil make most of theirs with hydroelectric dams.
We could reduce the per-capita need for electricity quite dramatically through greater use of efficient technologies. We could also make greater use of wind (although wind comes and goes—often quite quickly—so that if there is a lot of wind power, methods are needed to back it up). For the foreseeable future, solar is much too expensive for general use.
When natural gas is burned (e.g. in gas turbines) it produces about half as much CO2 per kW-hr of electricity generated as coal. That’s good, but the US has limited amounts of gas, the price of gas has fluctuated dramatically in recent years, and becoming more and more dependent on gas means becoming dependent on importing large quantities in LNG tankers from some insecure and unreliable parts of the world. That is not good for achieving "energy security."
For these and several other reasons, almost all serious analysts who have looked at the problem of reducing CO2 by something like 80% by 2050 have concluded that there is no way to do this without some continued use of coal.
Unfortunately, these analyses show that at least for the next few decades there is no "silver bullet" that can solve the problem. Especially when you include the billions of people in the developing world, it is going to take every low and no-carbon technology we can bring to bear. In addition to CCS, that includes: conservation/efficiency;
fuel switching; distributed generation with combined heat and power; nuclear; wind; solar thermal; geothermal and biomass.