Renergen Limited, an investment holding company, engages in the alternative and renewable energy businesses in South Africa and sub-Saharan Africa. The company explores for, develops, and sells compressed natural gas, as well as liquefied natural gas and helium gas. It also develops Cryo-Vacc technology, which offers transportation of vaccines at low temperature without any electrical power. The company was founded in 2005 and is based in Sandton, South Africa.