Bezpieczeństwo energetyczne rynki surowców i energii, teraźniejszość i przyszłość – gospodarka zasoby naturalne i logistyka, 2014 The idea of building interconnectors between the transmission systems of the EU Member States is evolving and getting more visible in Poland. This approach is a part of the implementation of European Energy Policy, which aims to strengthen cooperation between Member States' energy sectors. Combining transmission networks in the EU has also been included as one of the strategic objectives of the national energy policy and a tool of ensuring security of supplies. It is pointed out that the EU needs a fully functioning, connected and integrated internal market of energy, so that no country is isolated from the European network of transmission. The article discusses the grid investments in Poland and make comments on national interconnections in the context of their use of free bandwidth.