US climate solutions investor Hannon Armstrong Sustainable Infrastructure Capital Inc (<a href="https://www.nyse.com/quote/XNYS:HASI" target="_blank">NYSE:HASI</a>) and local private equity firm KKR & Co (<a href="https://www.nyse.com/quote/XNYS:KKR" target="_blank">NYSE:KKR</a>) have joined forces to invest USD 2 billion (EUR 1.85bn) in sustainable infrastructure projects across the US over the next 18 months.