A (Bio) Hydrogen Opportunity
We've talked before about baby steps toward a hydrogen economy. Those are important to keep in mind, but if we are ever going to completely transition, we need to solve the problem of massive amounts of cheap hydrogen made from renewable sources. Reforming oil or natural gas is fine for the short term, while you figure out the long term, but you still end up with the same carbon emissions as you had before, and the atmosphere heats up just as fast. Proposals for creating hydrogen from solar electricity, geothermal sources, and wind power are all enticing, and will definitely be a part of the process. But we wonder how these methods can expand to fill the 68% of energy usage gap left by oil and coal in the US (and probably only slightly lower in other countries); why aren't we already completely replacing our coal power plants with solar or wind?
If the answer is cost, and it very well may be, there is a huge opportunity under development by biologists around the world. With the adoption of a biotic system for producing hydrogen, you would loose the costs of upkeep and heavy price of expanding the system; Bacteria and algae take care of their own upkeep, and if you want more of them, the reproduce automatically!
Recently, there has been considerable press about "newly discovered" hydrogen producing bacteria in hotsprings and thermal vents. While new species are being found all the time, the genera has been researched for at least 15 years and has considerable success under its belt.
To generate biotic hydrogen, there are two main methods. Both involve collecting energy from the sun in plants, and then converting that stored plant energy into hydrogen with a bacteria.
The first, and most successful method to date, involves feeding special bacteria a diet of plant starches. In the real-world scenario, waste starch from a food processing plant, which would normally be discarded, or sold as livestock feed, is pumped through vats containing bacterial cultures. This starch "food" is full of photosynthetic energy stored by the potato, corn, or wheat plant. The bacteria break the "food" down, just as you break down a hamburger, except one of the by-products of this metabolism is hydrogen gas. In some situations, a gas which is up to 43 percent hydrogen can be extracted continuously from the vats. A major benefit of this system is that the bacteria do not need exposure to sunlight to break down the starch, which allows the power plant to have a small, city-scale footprint. Infectech has recently announced work on such a system.
The second method, while less efficient, is completely self contained, and ideal for situations like emergency power supplies, remote outposts, and small-scale generators which do not have ready access to large amounts of waste starch. Rather than using an external plant to generate starch, a symbiotic system involving algae and bacteria are used. The algae uses sunlight, water and carbon dioxide to make a hydrocarbon molecule, which is passed to the bacteria, which "eats" it, freeing carbon dioxide and hydrogen. The CO2 goes back to the algae to be used again, while the hydrogen is collected. As a bonus, the algae generates oxygen, which could make this system apt for space station fuel/air supplies.
These systems are still in their infancy, but this is the perfect time for designers and architects to begin thinking about how their introduction might alter the social and urban landscape. First of all, now that the fuel for cars no longer needs to be refined meticulously, or at least it's refinement will not require huge, ugly plants, what opportunities for integration into a city are there. Could every filling station now be simply a starch-hydrogen conversion station? Or, even more interestingly, if the algae-bacteria system is favored, how do we increase the area of sunlight available to these reaction chambers without just building them all in New Mexico and wasting all our newly made gas just shipping hydrogen around? Maybe some form of hydrogen generating sky-scraper covering would turn the buildings from an insurance liability to a big chunk of black in the balance books.
The possibilities are intriguing, as always. It's certainly a cool time to be designing.
Copyright 2004-2006 Dominic Muren and IDFuel Team