Investment in renewable energy needs to increase significantly to address climate change. Large institutional investors with huge asset bases, such as pension funds, mutual funds, insurance companies, and sovereign wealth funds, can be a prime potential source of capital for renewable energy. One way to ensure increased investment commitment from such investors is for them to treat clean energy as a separate asset class in their portfolios. Through this paper, our aim is to present initial insights into the potential effect the addition of clean energy listed equity as a separate asset class can have on existing portfolios. We focus on the value of listed renewable energy equity in a static portfolio optimization problem. Our main finding is that treating renewable energy listed equity as a separate asset class within an investor’s portfolio does not appear to add value to that portfolio. On one hand, this may reflect the need for applying more sophisticated techniques to show value. On the other hand, it may also imply that governments, policy makers, and regulators must keep working to ensure the clean energy sector is conducive to mainstream investment.