Renewable energy infrastructures are high-value assets that are managed by professionals with different roles. Commercial Managers are responsible for the financial monitoring and optimization of the assets, invoices and accounting, and in general, the commercial representation of the power plant in the relationships with contractors and the administrative authorities, on behalf of the owner. Technical Managers deal with the technical part of the plant, such as technical monitoring and optimization. Asset Managers are focused on profitability in the long run, they renegotiate technical and financial contracts if beneficial for the assets owner and prepare global reports that include all aspects of the plant management. Portfolio Managers have a different role: they seek the best risk-return approach for their customers by analyzing the market globally and proposing diversification and extension strategies. Understanding how renewable energy assets are chosen to form diversified portfolios, the different diversification factors for renewable energy assets from a theoretical point of view (Modern Portfolio Theory and Capital Asset Pricing Model), and the type of investors and forms of investments is useful when it comes to comparing renewables investments with investments in the infrastructure sector or within the same RE sector. Finally, it is worthwhile to dive into the world of sale and purchase of projects and portfolios. This discipline is often referred to as mergers and acquisitions (M&A) although there are more acquisitions than mergers in the renewable energy sector.