Reuters: Abu Dhabi’s Masdar, a clean energy venture, and Japan’s SBI Holdings Inc (8473.T) may invest up to $300 million in Japanese alternative energy start-ups through a joint investment fund, SBI said on Friday. Masdar’s investment vehicle, the Masdar Clean Tech Fund, and SBI have agreed to each put up $10 million to create a first fund to invest in firms involved in solar, wind and other alternative energy, SBI officials said. Each firm would receive around $2 million. The …