Nuclear, solar, and smart grids

Nuclear power and solar power are two completely different beasts for the world of smart grid.

Nuclear power:

• is produced far from the consumers, in extremely large plants, and the energy must flow on the transmission lines to get to the loads;
• cannot be turned on and off whenever you want: a nuclear power plant is almost always in operation, producing a constant amount of power
• the environment does not interfere in any way with the power production: day or night, cold or warm weather, a nuclear power plant doesn't care;
• produced power has a cost, and therefore nuclear power plant participate in the energy market.

Solar power:

• is produced in extremely small plants (even single panels on the roofs of the houses), and it is produced INSIDE the power distribution network, very close to the loads;
• its production is highly unreliable and intermittent: it changes naturally during the day (zero at night), and depends on the weather;
• it does not have any production cost: once the panels are in place, any energy that is produced is free;

As  you can see, these two power sources are extremely different, almost one the opposite of the other. This is one of the biggest challenges for a smart grid: integrating distributed generation (including solar) in a power grid in which old-style plants (including nuclear) are already there.

It is still an unresolved issue: right now, even if solar panels were free to build, the power grid could not operate on solar panel only. At the same time, nuclear power alone is not capable of following time-varying demands of the loads. The integration of the two, together with other sources (see also hydro) is the key to success.