In the wake of a recent post , I will try to explain in clear terms for IT people why alternative sources of energy will never replace traditional ones, and why, in the light of the exhaustion of oil and gas reserves, you need to switch to atomic energy.

Imagine you are the mayor of a small city. And you have a task - to provide the city with electricity. The old coal-fired power station is breathing its last and smoking too much. At the same time, as a rational person, you are going to solve the problem taking into account the prospects: your city is growing and, sooner or later, you will have to increase the production of electricity.

Thus, the goals of technology replacement are quite correlated with those for some Internet resource. Need to:
(a) ensure reliable performance at the current time;
(b) lay the scalability of the architecture for the future.
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So, what is offered to us from alternative energy sources?

1. Wind. You put a farm of windmills - and here it is, pure energy! However, for this it is necessary to allocate an open space for the farm, where the winds constantly blow. Well, if you have a good place near the city (really, you were going to break up a park there or make a plantation there) - and if there is no such place?

Can you provide a reliable supply of energy? Of course not. No wind - no energy. The power of the windmill is proportional to the third degree of wind speed - the wind speed has dropped twice, the power of the windmill is eight.
Can you make your architecture scalable? If you don’t have Rocky Mountains around there, then there are few places suitable for windmills. The wind farm occupies a very rather small area by itself + because of the noise it is necessary to move it away from residential areas.

2. The sun. Also, looking good. You put the panel - you get energy. This, of course, if the weather in your area is good. But, again, let's say.

Can you provide a reliable supply of energy? Not if you are not in Atacama. Adverse weather conditions leave the city without electricity.
Can you provide scalability? Here everything again comes up against the square. If you have a place and time, then yes, you can.

3. Hydropower. Well, everything is simple - if there is a suitable river nearby, you can block it. It will work like a clock, but forget about the increase in power.

4. Exotics. Geothermal / tidal power. In general, roughly the same problems as with wind turbines.

What we have? All alternative sources are fundamentally affected by the following problems:
(a) do not guarantee the desired power; many do not guarantee at least some minimum power;
(b) require the transfer of vast suitable areas for a farm / reservoir; however, there is usually no choice where to place the farm;
(c) do not scale well or do not scale at all.

If we draw an analogy with IT, then alternative energy sources are like enthusiasts who provide their power for solving scientific problems. Yes, it is quite a large and under-used resource, but, in many cases, absolutely inapplicable.

What provides us with nuclear energy?
(a) an absolutely predictable and reliable source of energy - how many megawatts are needed, put as much into the project;
(b) a highly scalable source of energy; there was not enough power - build another power unit. At the same time, it is not necessary to build a new farm, usually - a new power unit is being built within the existing NPP complex and does not consume additional space.

At the same time, the nuclear power plant, although it also requires a large allocated area, compares favorably with alternative energy in that you are completely free to choose a place — put it wherever you want.

Instead of conclusion

Why is there no alternative to nuclear energy? Because no alternative energy source is able to provide a reliable, predictable and scalable energy flow. Here the question is not at all in price, not in harm to the environment, but only in the fact that without the existence of a reliable component that does not depend on external conditions, not a single large energy system can exist.

Some studies cite a figure of 25% as the limit for the share of energy produced by unpredictable sources (lost link). It is argued that with a larger share, normal dispatching and transfer of capacities in the power system are simply impossible. In an amicable way, so far no large power system has encountered this problem.

It is possible that with the development of technology this figure can be exceeded, but, in any case, the power system must have a component that generates a predictable and scalable amount of electricity. At the moment, there is no alternative to nuclear power plants in this place (well, not counting the burning of hydrocarbons, of course), and, most importantly, not foreseen. Therefore, if we talk about long-term prospects, then, ideally, something like this structure should emerge:

- about 50% of electricity is generated at nuclear power plants and traditional power plants;
- about 50% of electricity is generated by alternative energy sources (and by the maximum - by hydroelectric power plants);
- all consumers are built into a single energy dispatching system, which can rebuild the energy flow in time for large drops of “alternative” power.

UPD: My old article about EROEI helps to understand what is happening in the power industry and why.