Marine algae get the green light from Shell

New Scientist ^ | 22 December 2007 | New Scientist

[isaiah55version11_0]

SHELL is to become the first major oil company to produce diesel fuel from marine algae. Algae are a climate-friendly way to make fuel from carbon dioxide. They produce an oil that can readily be converted to diesel, and can be fed CO2 directly from smokestacks. Unlike biofuels such as corn, they don't use up soil or water that could otherwise be used to grow food, which can pump up food prices. The US government abandoned research on algal biofuel in the 1990s because of the low cost of crude oil. But as oil and food prices began to rise, small algal fuel producers sprang up. Shell plans to begin construction on a pilot plant in Hawaii immediately, which it expects will produce 15 times as much oil for a given area as other biofuel crops, thanks to the efficiency of algal photosynthesis.

[mvpel]

You can grow algae in clear plastic tubes on the sunny side of the smokestack.

[Moonman62]

Somewhere off in the future somebody will be complaining about shortages of CO2.

[mvpel]

Actually, cracking CO2 into oxygen and methane is a very simple, exothermic reaction, provided you have hydrogen to feed into it. And you can generate hydrogen using solar-powered photosynthesis.

[ckilmer]

The most productive way to produce biodiesal is to use algae. Last year a cambridge company harnessed the CO2 output of some coal plants in arizona to their algae cannisters. The stuff grows fast and the oil yield on the algae they used was many orders of magnitude higher than any other agricultural substitute. Currently tests are running in arizona to scale up production into greenhouses. If you can convert the CO2 output from coal plants to oxygen with greenhouses full of algae producing biofuel--you've solved several problems.

[Reeses]

Algae can also be grown dry such as in lichen, an algae / fungus symbiotic relationship. I bet algae can grow on fabric sheets without the fungus to be used in filters. A problem with liquid filled vertical tubes is the pressure climbs with length. The algae might not do well with a significant variety of water pressure.

[Texas Mulerider]

Good idea. Build the power plant and the algae farm/refinery next to each other and pipe the CO2 to the farm: perpetual motion.

You're too late!

GreenFuels Technologies

[mvpel]

Use flat tubes and simple mirrors on heliostats to avoid the pressure differentials.

[Redleg Duke]

Waiting for the Sierra Club and Earth First to scream for protection of the endangered Marine Algae!

[Brad from Tennessee]

Thanks for the link.

[null and void]

Way off topic, but wasn't Soylent Green supposed to be marine algae before it was found to be made from people?

Dunno. I always assumed it was supposed to be made from soya beans and lentles. Hence the brand name...

[dan1123]

>> And you can generate hydrogen using solar-powered photosynthesis. <<

I’m pretty sure you meant electrolysis—which does require water.

[PapaBear3625]

Leaving the algae alone would do no good. Eventually the algae die and are digested by bacteria, which release the CO2 as waste gas.

Unless it was marine algae which sank to the bottom of the sea. In the dark, cold, oxygen-poor environment of the ocean floor, it would eventually be covered with sediment, and be turned into coal or oil a few hundred million years from now

In the iron-poor antarctic waters, all you would need is seed the water with rust to produce an algae bloom

[conservatism_IS_compassion]

But on second thought, even producing 15X as much bio fuel as we do today won't really make a dent in energy dependence.

You gotta start somewhere . . . and this sounds like it might actually be economically viable at present petroleum prices.

And although the algae is grown from CO2, when algae diesel is compressed in a diesel engine with super heated 02, the byproduct is C02. So if you really want to reduce C02, shouldn't you just grow algae and leave it alone?

Alone? Alone with the bugs that will rot it and give off the CO₂ spontaneously, you mean?

The production of diesel fuel is an economic process. The production of Carbon Credits - which is what you are in effect advocating - is a scam, pure and simple. In any event, if algae biodiesel replaces petro biodiesel then it actually does reduce CO₂ overall.

[pfony1]

ping

[MainFrame65]

==> “Solar cells would be simpler in the long term with vehicles going electric. In the short term the algae diesel can drive transportation.” <==

The energy required for transportation is orders of magnitude greater than the total solar energy impinging on any kind of practical vehicle - even assuming 100% conversion efficiency. Yes, I know about the cross-country solar car races and the solar powered airplane, but those are totally outlandish vehicles, built solely for the purpose of competing for the prize, and impractical for any productive use.

The transportation fuel of the future will be almost identical to the fuel of today - light liquid hydrocarbon compounds. Nothing matches it for convenience, safety, and energy density on this planet. But it will be synthesized from raw material sources insted of being refined from crude oil.

This algae appears to be a very effective way to harness photosynthesis. It uses solar energy to break down CO2 to release oxygen to the atmosphere, capture the carbon, combine it with hydrogen from seawater (releasing more oxygen,) and produce hydrocarbon fuel from these raw materials. Looks good to me.

[Brad from Tennessee]

I appreciate the information and your scientific expertise. I wasn’t envisioning any vehicle propelled by the sunlight it absorbs but I wasn’t very clear. I was talking about electric cars whose batteries are charged from a power grid that may in the future be based on solar. Of course, the batteries don’t exist yet or the practical (cost per kilowatt) solar technology.