I'm from Germany and I'm supporting our move to 100% renewable electricity production by 2050 or earlier.

It will be interesting to see what the US does.

Let's say coal and gas are much more dangerous than nuclear and nuclear is the way to go.

Let's also say renewables is not a way to go, because many people die from erecting wind mills, bio mass plants and solar panels. Chemicals for solar panel production are dirty and rare earth minerals need to be mined, too.

http://en.wikipedia.org/wiki/Electricity_generation

Currently 20% of electricity in the US is generated with nuclear power stations. There are around 100 in operations. Many of them are extremely old and some even sit in dangerous regions with earth quakes. Let's say 20 of them have to be shutdown soon.

68% of the electricity are provided by coal (45%) and gas (23%) power plants. That is 3.4 times more electricity.

Now the US is going to replace the dangerous and dirty coal and gas with nuclear.

So you need around new 250 nuclear reactors to phase out coal and gas. Maybe less, because newer nuclear reactors generate more electricity. Maybe more, because the electricity demand may rise.

Let's say a nuclear power plant and its direct infrastructure will cost around 5 billion a piece, that would be 1.25 trillion $.
That sounds much, but given that the US spends a trillion a year on 'defense', it might not be much. May be the price will go down with production of 100 and more reactors.

Given that the political parties may want to have small government, the majority of the nuclear reactors will have to be financed and operated by companies.

So the tasks are:

* find a way to finance one or two trillion dollars

* decide and standardize on a new reactor design with inherent safety

* build up companies who will plan, build and operate the nuclear reactors

* find places for 250 new reactors (in addition to the existing 100)

* build, say, three reprocessing plants for those

* build, say, three breeder reactors

* find, say, three storage sites for nuclear waste

* get mining and an fuel enrichment going

The result would be about 85% electricity production with nuclear reactors and complete phase out of gas and coal power plants.

What is the time scale for this? The full development of a new type of reactor can be done in, say, 10 years. Add dealing with regulations, tests, ... - one may need 20 years. Let's be optimistic and say ten. A new reprocessing plant, would need, say, 10 years. A new storage site, say, 30 years.

So in the first ten years no reactor would be ready. That's pessimistic, since there might be reactor designs that can be built earlier - it is optimistic, since a really new design may need more time. Also the US has not built commercial reactors for some time, so there is some time needed to get this going again.

* 1st. decade, zero power plants

* 2nd. decade, ten power plants + a reprocessing site

* 3rd. decade, thirty power plants + another reprocessing site

* 4th decade, fifty new power plants + another reprocessing site, plus a new storage site

* 5th decade, 100 new power plants + a new storage site

* 6th decade, 100 new power plants

Result: new 290 nuclear power plants, 3 reprocessing sites, and two long term storage sites.

This would also allow to shut down some of the older ones.

These are just assumptions.

That's basically what France did, now scaled to the US. France has 65 million people and less electricity usage per person. The US is now at 300+ Million people. That's around 4.5 times more. France operates around 50 nuclear power plants. So, 350 in total in the US needed would be a good assumption (given some constraints, like that France is very centralized and many people live around Paris). France also has a shrinking population, where the US is still growing - last I looked.