 GUY HaNDS is rebranding. The private equity tycoon is best known for losing hundreds of millions of pounds on a disastrous investment in EMI, the music company. But his private equity firm, Terra Firma, which in February finally ceded control of the label behind Katy Perry and adele, "is bigger than EMI", Hands said.  "We are by far the world's largest private equity investor in renewable energy generation, and we have been for some time."  Last week Hands sealed the largest takeover in the solar industry, spending (EURO)641m (?566m) on Rete Rinnovabile (RTR), an Italian company that owns sites capable of powering 150,000 homes from the energy of the sun.  The deal is the latest in a string of big bets on low-carbon technologies and came as he put another of his investments, Odeon &amp; UCI Cinemas Group, up for sale.  In Britain, Hands owns Infinis, the country's bigges 