US energy-as-a-service provider Sunnova Energy International Inc (<a href="https://www.nyse.com/quote/XNYS:NOVA" target="_blank">NYSE:NOVA</a>) has booked a third-quarter net loss of USD 122.6 million (EUR 112.9m), expanding its year-ago deficit of USD 63.1 million as growing costs outweighed the increase in revenues.