Biofuels’ 10 scariest challenges: Part 1 of 2

7. Pests, predators, competitors, contamination

If you’ve been hoping that algae solves all bioeconomy problems — specifically low-cost open pond algae technologies — welcome to the problem of crop protection.

Scarecrows in the corn fields, pesticides, herbicides, adding traits for resistance to drought or disease. Crop protection systems abound — but not much has been developed for algae.

Because of the way algae is grown and produced in most algal ponds, they are prone to attack by fungi, rotifers, viruses or other predators. Consequently, algal pond collapse is a critical issue that companies must solve to produce algal biofuels cost-effectively. The issue was identified as a key component in the Department of Energy’s National Algal Biofuels Technology Roadmap.

To address the problem, this past spring a team at Sandia National Laboratories and the Arizona Center for Algae Technology and Innovation debuted a suite of complementary technologies to help the emerging algae industry detect and quickly recover from algal pond crashes.

But if pestilence, disease and predation is not enough for you, consider the problems of contamination.

As we saw in the launch of Gevo’s first commercial plant at Luverne, it came down to strains of bacillus, a rod-shaped, single-celled bacteria with an insatiable appetite for dextrose, or corn sugars.

Microbial infections are a common feature of world-scale fermentation — especially in their commissioning period — they’re a common nuisance with ethanol plants, also, that have developed antibiotics and other strategies to combat them.

As Gevo CEO Pat Gruber observed, in talking with the Digest, “First step was, for us, to make sure we understood all the competitors that are chewing up the sugar, eating up yield. There’s no way to know until you do it, at scale. What matters is how you respond.”

Bacteria lurk. Picture the small white infection spots you see on a child’s inflamed tonsil when tonsillitis or strep throat strikes — and parents will know that those type of infections can go away and then suddenly strike again. Those are lurking bacteria that have found a happy home, hung up in a tube somewhere inside the body — lying in wait for the right conditions to appear, and then spring back into view.

It is not completely different with microbial contamination in fermentation systems — likewise, the microbes embed themselves in small infection pockets, and then rise up in numbers when the sugars start to flow.

“You are always going to have microbes, whether they come in through the air or water,” said Gruber. “But there is ‘manageable’, and then there is ‘outnumbered’.

In today’s Digest, follow the page links below for each Scary Challenge – and potential solutions.