The L&G Clean Energy UCITS ETF is a listed Exchange Traded Fund that invests in Clean Energy companies

https://fundcentres.lgim.com/uk/professional/fund-centre/ETF/Clean-Energy?isin_code=IE00BK5BCH80

The L&G Clean Energy UCITS ETF (the “Fund”) is a passively
managed exchange traded fund (“ETF”) that aims to track the
performance of the Solactive Clean Energy Index NTR (the “Index”)

https://www.londonstockexchange.com/stock/RENG/legal-and-general-asset-management/company-page

The graph speaks volumes