Koch brothers secretly funding groups opposing energy efforts?

Came across an interesting article in Intelligent Utility today [click here for full article] - according to this article, Koch brothers [David and Charles Koch of Koch Industries which is a multi-billion dollar energy conglomerate] are spending millions of dollars promoting groups that call for abolishing DoE and US EPA. It's their right to promote whatever view point they hold dear - but the issue here is that their funding of various "grass roots groups" is opaque and so, unless one has the resources and patience to dig through various filings and other information, most people will not realize that these groups are actually a front for Koch.