Major utility provider Iberdrola has used blockchain technology to “guarantee” that the energy it supplies to its customers comes from 100 percent renewable sources.

In an announcement Monday, the firm said that it had undertaken an “experiment” with the financial entity Kutxabank. Using blockchain, Kutxabank was able track the origin of energy supplies, in real time, “from the generation asset to the point of consumption.”

The energy was produced at wind farms and a hydroelectricity plant, and used at the headquarters of Kutxabank, in the Basque Country, and Cajasur in Andalusia. Cajasur belongs to the Kutxabank Group, according to CNBC.

Blockchain technology is starting to become an important tool for many industries, including the cryptocurrency sector.

Broadly speaking, it refers to a tamper-proof, distributed digital ledger that records transactions.

Instead of different parties involved in a transaction keeping their own records — which could potentially differ and cause confusion — blockchain creates one “master” record. This cannot be changed once a transaction has been recorded.

For its part, Iberdrola said that blockchain technology was a way of allocating “which assets will supply energy to a specific point of consumption.”

It added that its initiative meant that renewable energy certification processes were sped up and automated, with certification “given a greater degree of traceability.”

The transaction was more secure and transparent because it was “permanently registered on the platform so that both parties can audit the results.”