Clearly, the world needs a massive amount of carbon-free electricity by 2050 to stabilize greenhouse gas emissions....
This electricity must meet a number of important criteria. It must be affordable...at most about 10 cents per kilowatt hour, a price that would probably beat nuclear power and would certainly beat coal with carbon capture and storage...The electricity cannot be intermittent and hard to store, as is energy from wind power and solar photovoltaics. We need power that either stays constant day and night or, even better, matches electricity demand, which typically rises in the morning, peaks in the late afternoon, and lasts late into the evening.
This carbon-free electricity must provide thousands of gigawatts of power and make use of a low-cost fuel that has huge reserves accessible to both industrialized and developing countries. It should not make use of much freshwater or arable land, which are likely to be scarce in a climate-changed world with 3 billion more people.
Solar electric thermal, also known as concentrated solar power (CSP), meets all these criteria.