GreenVolts raises $22.4m from 19 investors out of a planned $38.8m round.

GreenVolts, a US-based company providing solar power concentration technology for utilities, has raised nearly two-thirds of its latest round of financing.

In a regulatory filing first seen by data provider CB Insights, GreenVolts has raised $22.4m from 19 investors out of a planned $38.8m round.

Previously, Greenvolts raised $30m in September 2008 for its series B round from venture capital firm Oak Investment Partners. Its $10m series A round the year before came from Greenlight Energy Resources, an…