Blockchain is a technology, which could revolutionize many industries in the future. A system like that is based on a chain of blocks that is used for storing and transferring various data, forming a decentralized ledger. Although various fundamental projects based on the blockchain system in the energy industry are in their early stage of development, as well as other solutions, applications of blockchain technology in the broadly understood power engineering sector are considered to have a very large potential. This paper presents a brief description of the blockchain technology, its general operating principle and the possibilities it brings. The next section of the article contains a characterization of two exemplary and possible blockchain technology applications, which in the perspective of time may have a significant impact on the power engineering sector. The first solution is related to carrying out energy transactions, which could be conducted in an easy way directly between energy producers and consumers. Thanks to blockchain technology, this could lead to a partial decentralization in that area. The second proposed example concerns energy resources origin tracking, which would allow fixed origin attributes and parameters affecting the environment to be assigned to the generated energy. By implementing that solution, it would be possible to construct a fuel footprint of individual generating units. The article also mentions examples of other potential applications of blockchain technology in the power engineering sector.