The price for sustainable development of renewable energy sector: the case of Ukraine Iryna Sotnyk, Tetiana Kurbatova, Oleksandr Kubatko, Yevhen Baranchenko and Rui Li E3S Web Conf., 280 (2021) 02006 Published online: 30 June 2021 DOI: 10.1051/e3sconf/202128002006