Pond scum could fuel fighter jets and go a long way toward cleaning up power plants, which is why the Pentagon, Silicon Valley, and some of the world’s top research institutions are digging into it. One place algae’s having a tough time making inroads, however, is in a multibillion-dollar section of the economic stimulus bill that could mean the difference between nascent carbon recycling technology crossing over “death valley” into commercial viability—or facing a major battle with coal companies’ underground carbon storage schemes for years to come. With Congress now working on a final version of the bill for President Barack Obama to sign by the end of the week, some algae entrepreneurs are asking why legislators have left them out in the cold.

The current Senate version leaves the door cracked open for a broader range of technologies, with at least $4.6 billion set aside for carbon capture and storage, including a portion for projects that demonstrate carbon capture from industrial sources. Algae technologies would be potential candidates for those funds.