Years from now, when their great-grandchildren ask "what did you do during the Great Financial Meltdown Of Ought-Eight?," the answer clean tech investors and technologists may give is, "what meltdown?"Two announcements from GE this week underscore that forward momentum continues in the clean tech sector, despite the pounding that the financial markets have been enduring for weeks.

On Wednesday, GE announced that it is investing another $30 million in A123 Systems, becoming the largest single cash investor in the Massachusetts-based battery maker. The sixth round of equity investment brings GE's combined investment in A123Systems to $55 million, and gives GE 9% ownership.

Any joy felt around A123's Watertown headquarters might have been tempered by reports Wednesday that GM will go with lithium-ion batteries made by LG Chem for its Chevy Volt -- not batteries from A123 -- at least in the first generation of the plug-in hybrid.

But GM's official decision about a battery supplier (or suppliers) won't be known until in November.

With or without GM, GE is firmly in the electric vehicle space. In a visit to the GE Global Research Center near Albany, N.Y., Wednesday, I spoke with engineers who are working with A123Systems and Norwegian electric car maker Think to tweak the batteries for Think's City Car. Other researchers are developing battery packs for buses, construction ,and mining vehicles, and even locomotives.

Earlier in the week, GE stated that it expects revenue from its clean tech products and services will spike 21% to $17 billion in 2008. At the same time, the company's annual investment in clean tech R&D will exceed $1.4 billion.

Wall Street is taking a drubbing, but clean tech isn't dwelling on the gloom, not at GE, anyway. There's too much work to do.