Norway has a 100% renewable electric mix

Some countries have an almost 100% renewable electricity mix thanks to favorable geographical conditions, but this is difficult to generalize and apply elsewhere. Intermittent renewable energies do not guarantee stable production, requiring the addition of controllable means of production to the mix.

Very specific situations

Some countries do indeed have an electric mix that is almost 100% renewable. This is the case, for example, of Iceland [1], Norway, or Costa Rica. However, this situation cannot be generalized and is the result of a geographical position offering these countries abundant geothermal and hydraulic resources.

Difference between controllable and intermittent energy

To understand the obstacles to the generalization of a 100% renewable energy mix, it is essential to distinguish two types of energy. On the one hand, controllable energies, whose production can be adjusted as needed to meet demand. And on the other, intermittent energies, whose production is subject to external factors such as weather, sunshine, or wind. [2].

The necessary stabilization of the electricity network

In addition, to be usable, an electricity grid must remain stable under all circumstances, which means that production must constantly keep up with demand. However, this is impossible in a system where production is 100% ensured by intermittent renewable energies, as intermittent production, by nature, is not perfectly aligned with demand [2]. To compensate for this intermittence, it is mandatory to rely on controllable means of storage and production. As it stands, storage technologies, such as batteries or fuel cells, do not yet allow sufficient volumes to be stored to fully replace controllable means of production [3].

The only large-scale low-carbon storage solution is pumped-storage hydroelectricity (a system for pumping water from a lower reservoir to an upper reservoir using surplus available electricity), but this is not feasible everywhere, as it requires topographies and water resources that are relatively rare [4].