There may have been doubt about it until now, but Silicon Valley steadily is gaining status as a leading center of innovation for green technologies -- especially in solar.

Over the past year, we've reported all kinds of news about investments into clean-technologies here. Today, there are two more encouraging announcements showing the moneybags on Sand Hill Road are taking this seriously.

First, Innovalight, a Santa Clara solar company, has announced it has raised an additional $7.5 million in venture financing (downloads file) from Harris & Harris, Apax Partners, ARCH Venture Partners, Sevin Rosen Funds and Triton Ventures -- some of which have offices here in Silicon Valley.

The company says it has come up with a new way to build solar energy modules from the popular, prevalent silicon. Only, it won't do it using silicon in its costly, inflexible crystalline wafer state. It will reduce the silicon to nanosize crystal dots, so that it can be used as a sort of ink, where it can be painted onto surfaces.

This is intriguing, because it threatens to do an end-run around all the other companies that are working on nano-solar technologies based on materials other than silicon, such as Konarka and Nanosolar.

The start-up has just moved to Santa Clara from St. Paul, Minn., another sign that Silicon Valley is the place to be for the future of solar technology research. Nanosolar, Miasole, and publicly traded SunPower are already here.

Big cautionary note: InnovaLight CEO Conrad Burke, 39, says he wants to have a test product ready in a year, and have a product launch in two years. These are the sorts of time predictions made by some other start-ups a couple of years ago, and we've seen several of them slip. For example, we've yet to see Miasole's product launch, despite promises that it would come soon. If these new nano guys fiddle around too long, the cost of the regular, clunky silicon solar technology might come down far enough so that they lose a window of opportunity. Prices are high now, because silicon wafers are in tight supply; but that might change as factories start producing them in larger quantities. That doesn't change the fact that the new technology could provide valuable longer-term, though.

Here's a good article in Time about Innovalight.

Meanwhile, Piper Jaffray & Co.'s has created the first fund to invest dollars solely into venture capital firms that invest in clean technologies. It is called a "fund of funds" because it is a fund that is made up of investments into other funds, and VentureWire reports (sub required) that it is raising $50 million for the purpose, and that it has already committed some of that to venture firms out here in Silicon Valley/San Francisco, including DFJ Element LP, Expansion Capital Partners LLC, Nth Power and VantagePoint Venture Partners.