The paper presents two stages of an analysis of the storage capacity of low-pressure gas network for biomethane with a low value of combustion heat. The subject of the study is up-to-date, since it concerns an important issue of the storage and transport of energy generated from renewable sources. Based on the results of the gas flow simulation in the network in Polish city, the distributions of parameters describing the gas dynamics in the network were analyzed and the weak points of gas mixtures and alternative fuels transport in the network pipelines were indicated. Then, two methods of biomethane introducing and storing in the natural gas or regasified liquid natural gas LNG transported through the network were compared. The advantages and disadvantages of each solution were discussed, and the size of the biomethane stream, which can be introduced into the gas network pipelines and supplied to the recipients together with the gas was quantified. It was demonstrated that the highest volume of biomethane can be stored in the network transporting regasified LNG, and the biomethane stream, regardless of the network load, constitutes 39% of the mixture of biomethane and regasified LNG. In turn, the lowest biomethane volume can be stored in the network in the case of constant over time biomethane stream introducing into the natural gas. (C) 2019 Published by Elsevier Ltd.