Global wind and solar company Mainstream Renewable Power has signed an agreement with renewable energy investment company Aker Horizons, which will take a 75% equity stake in the company, subject to regulatory approval. The deal values Mainstream at €1-billion (including a potential earn-out of up to €100-million in 2023 and subject to customary adjustments), which represents a significant return for shareholders of up to 5.5 times investment, the company acclaims.