**3.1 Energy sector considerations regarding the previous section**

The smart grid itself is a network of IIoT devices and is also considered a critical infrastructure, so everything mentioned above about the advantages of using blockchain in IIoT devices obviously applies directly to this industry.

Traceability is also relevant in the energy industry; therefore, at the end of 2018 ACCIONA announced, in collaboration with Tecnalia, the first proof of concept for the use of blockchain to trace the renewable origin of energy. In this case the fundamental objective of traceability is to guarantee the renewable origin of the energy and thus differentiate the energy generated in a sustainable way.

Even so, since the initial experimentation, there are several utilities that have made different proofs of concept, and we must distinguish between (i) the traceability of energy from its point of origin, with information collected from the IIoT itself (smart meters of the power plant) or (ii) the traceability made retrospectively based on the data that the utility itself (not the machines) introduces in the blockchain. The first one gives a total guarantee and trustworthiness; in the second case, the reliability is given by the utility itself and does not have a superior value than a report signed by the energy company itself.

Equally important is the interoperability and sovereignty of the data in a smart grid in which different operators and manufacturers collaborate with a common industrial objective—the grid resilience—but with competing business objectives.
