It is not possible to build nuclear reactors in hot countries.

It's a myth. Many nuclear power plants operate in areas with a desert climate, such as Barakah in the United Arab Emirates or Palo Verde in the United States. The latter even uses wastewater from the city of Phoenix for cooling.

The need to cool nuclear power plants is often presented as an absolute limit preventing any nuclear reactor installation in tropical or arid countries. This misconception is often fueled by the shutdowns of some French nuclear power plants during heatwaves. It is important to bear in mind that these shutdowns are not due to a technical impossibility to operate the plants above a certain temperature. They are in fact the result of regulatory constraints aimed at preventing an excessive rise in the temperature of waterways. [2]

There is no shortage of examples

In reality, a relatively large number of nuclear power plants are built in "desert" or "tropical" areas. For example, the power plant in Palo Verde, Arizona, located in the Sonoran Desert, has the particularity of not being located near a river or the coast. The plant, which is also the largest in the United States, is cooled using wastewater from the city of Phoenix [1].

The famous Chinese EPRs of Taishan are located in an almost tropical area. The initial design of the EPRs was somewhat "tropicalized" to be more suited to local conditions. [3]

All this demonstrates that there is no real technical impossibility to building and operating nuclear power plants in areas with a tropical or desert climate.