By Leticia Fucuchima SAO PAULO (Reuters) -Crypto mining companies are actively negotiating contracts with Brazilian electricity providers, such as Renova Energia, that would benefit from the South American country's surplus renewable power without burdening the grid during peak times. Following crypto heavyweight Tether, which announced in July an investment in the South American country, there are at least six negotiations for small and medium-sized enterprises, as well as one for a larger project of up ...