South Korea’s Samsung Group will invest $21bn in renewable energy and healthcare over the next decade, seeking “mega-trends” to help the world’s biggest electronics maker diversify away from its computer chip and mobile phone businesses.The ambitious investment plans are expected to clear years of uncertainty over the group’s future business direction. Samsung, which is South Korea’s biggest conglomerate, generates one fifth of the country’s exports.The new investment plans will help Samsung challenge rivals such as General Electric, Philips Electronics and Sanyo Electric in the long term.The strategic investment decision comes less than two m