Cont.
....in optimal conditions conditions. Under normal conditions, depending on use and equipment, 30-67% could be expected, favoring upper 50's range.

Sadly, the economics of this system aren't that favorable, are they? You can't scale it up, the bioreactors cost a fortune. That's why the Aquatic Species Program concluded very rapidly that algae photobioreactors are no option; open-pond systems result in very low biomass yields because algae cultures become unstable.

Oil prices will have to get a bit higher probably for this to be profitable, and the US will have to develop a carbon market to put a price on each tonne that is saved. Else, I think this is a loser.

Gio: Have you seen some numbers for the cost? As for oil prices, they are likely to fluctuate wildly over the next 5 to 10 years of so before going through the roof. These people are thinking ahead.

Hi Neil, no I haven't seen any data on the costs of the system, but remember: the Aquatic Species Program was launched in the late 1970s, early 1980s, when oil prices were much higher than they are today. Even then, photobioreactors were not seen as economically viable.

Still, if there's a price for carbon and a working carbon market in the US, the picture may be different.

The Japanese also fiddled with closed reactors for a long time and discovered they weren't worth the trouble. You really do need quite a large area to grow algae, so the facilities have to be as low-tech as possible, e.g. shallow open racetrack ponds, possibly heated in winter.

An even more promising route is growing marine oil algae out on the open ocean near the equator. Sections of it would be cordoned off using a suitable floating skirt construction incorporating pylons with electrically powered azipods and networked GPS-based position control systems. CO2 concentrations in the open ocean are two orders of magnitude greater than those in the atmosphere. Rapid harvesting of the dissolved CO2 means the entire system would have to move around slowly to let natural diffusion processes restore the original CO2 concentration. A nomadic approach also allows the facility to steer clear of areas prone to tropical storms in summer.

The algae would be harvested by ships roaming inside the cordoned-off area, pre-processed on-board and transferred to a floating transesterification plant that doubles as the entire facility's HQ. It would produce its own biogas and methanol and, turn the glycerol to syngas for electric power generation etc. To avoid fungal growths, the FAME product would be adulterated with a small fraction of alkanes produced via FT prior to intermediate storage and final transfer to tanker ships.

To enclose ~1000km^2 of ocean, you'd need a skirt ~36km long. It would be a major engineering project, to be sure, but so are deep offshore oil rigs.

"Now, what if all the vehicles will run on H2, with H2 produced cheaply from CO2-fed algae farms? Is this a strong enough argument for further development into the Hydrogen Economy?"
As long as the hydrogen is used only to produce electricity, do whatever you want to with the junk. But don't expect the country to spend the trillions developing an infrastrucure for a fuel that is mostly useless to the consumer and, in any event, would be largely redundant. With the advent shortly of plug-ins, followed by all-electric vehicles, any conceivable reason for involving the consumer with hydrogen goes floating away if, indeed, there ever was one in the first place.

Rafael,

Do you have any URLs for the Japanese studies?

Gio: Found an entry on wikipedia:

"The July 1998 close out report from the program concluded that even with the most optimistic lipid yields the production of bio-diesel from algae would only become cost effective if petro-diesel prices rose to twice the 1998 levels. Note: October 2006 oil prices are three times higher than the average 1998 price in constant dollars."

The startup price of a system like this may be fairly large if compared to oil exploration (which is getting more expensive all the time) but must be (correct me if I'm wrong) significantly less than the cost of starting up an oil sands project in Alberta.

The economics of algae would be radically different than the economics of traditional fossil oil (with the exception of oil sands). The up front costs will pay off at a flat rate (as opposed to a curve) indefinitely.

Rafael,
Diesel coupled with hybrid drive, either electric or hydraulic, can also be very efficient, and can allow tank-to-wheel efficiency of almost 40%. Hydrogen with direct injection and multimode use, with ultra-lean burn at lambda 2-4 at partial load and stoichiometric at high load with NOx trap, can achieve ~45% efficiency, especially when coupled with a turbocharger or turbo compounding. The BMW 760h is very much compromised due to the need to use gasoline as well, and the lack of direct hydrogen injection, thus does not have sufficiently high compression ratio for optimum efficiency. Fuel cells are more expensive and does not have the durability of the ICE. The beauty of solar-algae-H2 is elimination of CO2 released to a large extent.

Kent,
Battery is out for trucking because the need for continous use that leaves no time for battery charging. Plus, battery would still be too heavy to provide the range required for trucking.
As I've outlined before, the cost of H2 infrastructure would be far less than the purchasing price of the battery packs for the same number of vehicles served by the hydrogen infrastructure.

But you have a good point. Let use H2 for electrical production first, and then any surplus H2 from expanding of algae farming can later be diverted for transportation use. One step at a time until the technology will be perfected. Sounds promising, though!

High-CO2-Algae-hydrogen route is better than photovoltaic route because of the inherent energy storage already exist with stored H2. PV electricity still lacks an economical means for large-scale energy stgorage. I would envision large shallow of nutrient-filled pans covered with double layer of clear mylar top for heat insulation in winter, or single layer mylar for summer, and filled with high CO2 concentration for enhancing algae growth. This is as low-tech as you can get, and investment cost should be substantially less than PV or concentrated PV set up.

gr -

I didn't find the scientific papers for the Japanese research online, but plenty of indirect references to its existence.

http://www.biodieselnow.com/forums/thread/32965.aspx

"Yes, you can use mirrors and fiberoptics to get a higher yield per acre (it doesn't boost the actual photosynthetic efficiency though) - but the cost increases at a faster rate. The Japanese spent a LOT of money and many years working on that approach, to try to grow algae underground in Japan, and finally gave up due to the exorbitant cost."

http://www.biodieselamerica.org/files/articles/Biodiesel%20from%20Algae.pdf
http://www.oilgae.com/algae/oil/biod/cult/cult.html
http://www.msnbc.msn.com/id/15287313/
http://hybridiesel.blogspot.com/2005/02/biodiesel-from-algae-long-way-to-go.html
http://www.greenfuelonline.com/news/algaefuel.pdf

Ok Roger: We've been down this road before. How about a compromise. Lets compare the cost of H2 infrastructure with any INCREMENTAL cost of BEV vehicles (assuming you are talking about H2 ICE instead of FCVs in which case the incremental cost is for the FCV). You will also need to factor in the higher cost of ICE maintenance. I suspect the cost of batteries will come down.

Roger:  Zinc-air fuel cells (primary batteries) can be refilled with metallic zinc in a few minutes.  The Altair Nano titanium formulation can be recharged to 80% in 60 seconds, so a heavy truck could charge in motion from a one-mile stretch of overhead power rails with flexible brushes on the truck.  Slow down to 55, pull into the charge lane, the computer raises the brushes and does all the hard work for you.  The more frequent the charging lanes are, the less batteries the truck would need.

20 miles of electric range would also let the truck leave the freeway, do most deliveries in cities, and return to the freeway without starting its engine.  Charging at the loading dock would double the off-freeway range.

I personally believe (or want to believe) that had President Gore not have had the White House stolen from him a carbon tax would have made this a national reality by now. Better late than never. Great job Green Car Congress for giving those that care a forum for their voice.

Eng-Poet,
That's a good idea, charging the battery while in motion. But you mentioned previously that it would take 6 minutes to charge an Altairnano battery to 80%, why 60 seconds now? Because increase the charging rate 6 times would increase the current load six folds, and that would really tax our already straining electrical grid. Even 6 minutes charging would require probably rewiring to add much heftier power lines from the power plants.
What's the spec on Zinc-air battery, and why not much mentioning of this as candidate for BEV's?

I believe there is also a group in Israel working on Magnesium driven cars. Wind in a spool of magnesium wire at a station and remove the oxidated magnesium as a powder for recycling. An interesting concept.

Neil, thanks for that reference.

Let us not forget, though, that biofuels produced in the developing world using non-deforestation crops, such as cassava and sugarcane, can be produced competitively when oil is above US$40pb. The cost of transporting them to importing markets (EU/US) is marginal.

In any case, it's good to see that there are many alternative biofuel technologies and approaches that will compete against each other. This will drive prices down over the long run.

Does anyone know if it is possible to compress light wavelengths, specifically the green&yellow band to blue and indigo (specifically 425-475nm)? I've been looking online and the subject is scant. I know some pigments do absorb and emit different wavelengths to assist photosynthesis. However, they are do not cover the green to yellow spectrum well. Even though ther are pigments that absorb yellow and green(~500-600nm), they work in concert, with other pigments, in a system akin to a bucket brigade, with leaking buckets. At every step, there are losses. After 3 or 4 handoffs and reaching chlorophyll a and b at the red end(640-660nm), the efficiency drops to 6-20%.

Allen -

photons are quanta of energy. Reducing their wavelength requires transferring energy to them. You can raise an atom into its primary excited state using a photon of the energy corresponding to its primary band gap. This excited state is unstable, but if you manage to hit that same atom with a second quantum of the energy corresponding to the difference between the primary and a higher excited state, the atom will reach that higher state, which is even less stable. The decay may happen in multiple steps, yielding multiple low-energy quanta (typically, but not necessarily of the same bandwidths as the inputs). Occasionally, the decay will happen in a single step, releasing one high-energy quantum.

So while it is not possible to change the wavelength of a given quantum this side of relativistic effects (known in astronomy as red and blue shift, respectively), it is possible to combine the energy of two low-energy photons of just the right wavelengths to yield one high-energy quantum, i.e. a concentration of energy rather than a compression.

The second law of thermodynamics is strictly speaking only applicable to macroscopic, classical systems. However, any system in an engineering application will be just that. Concentrating energy in one portion of the system reduces entropy, which is only possible if it is increased by at least that amount (in practice, by much more) elsewhere. Consequently, your yield of high-energy photons would be low compared to the amount of energy you put in.

That's ok only if the input energy (sunlight) costs you nothing but the yield of high-energy quanta has enough economic value to amortize the investment in the equipment, with some profit left over at the end.

When I hear the conversion efficiency of this may be between 2-10% and there is 1000 watts per square meter from the sun, I would think that it would take quite a bit of area to collect the kind of energy you would need for a power plant or to make fuel for many cars. It do not imagine that a square mile covered with these growing chambers comes cheap. Biomass on the other hand comes from the stalks of the plants they you are already growing on land, water and nutrients that you are already using. Seems like, if conversion efficiency of plants is about the same, it would be lower cost for biomass. The processing to energy would use similar methods, so the costs would be similar.

A member of the Fox Valley Electric Vehicle Club (near Chicago) built a car that ran off aluminum beer (pop, etc) cans in the 1980's. Cheap way to get Pacific Ocean Solar energy, by way of Pacific North West hydro-electric power which is used to make the aluminum from bauxite. Could still be done. Might make BEV's practical in cold weather - burn up a quarter pound of cans to get the car and battery warmed up from 0 F.

Allen,

Perhaps a suspension of green-yellow spectra reflective particles accelerated to blue shift velocities and amplified (stimulated emission of radiation) could achieve a "compression" of wavelength.

However I suspect there would be electro-motive energy costs that might not raise efficiencies much above the 20% bracket.

There are some interesting photon shift experiments with nano-fiber optics I looked at a while back - don't recall what spectra they were in but they were producing some surprising non-relativistic effects.

I may have missed it in the thread, but why not fit the photoreactors with artificial lighting powered from the power plant, and grow the stuff 24-7, thereby cutting direct emissions by around 80% continuously. This would seem to double the production for the cost of lights, and as was pointed cut total CO2 emissions by using the CO2 twice while curtailing foreign oil blackmail.

Van,

While that might reuse the carbon it would be a more negative energy balance. The energy from the sun helps the energy balance be more positive. When you start using electric lights the product costs more.

Van: I think you would find that it is not very energy efficient to combine the energy loss of generation with the energy loss of lighting with the energy loss of the algae absorption. Probably better to just store the overnight CO2 until morning.

You might have natural gas to electricity at 40% efficient, then electricity to light at 30% efficiency and conversion of light to energy by the plant at 2=10% efficiency. You might as well sell the NG or electricity, it makes more economic sense. Of course, you could run the other 18 hours with no sun, but that is like saying we are losing money, but we will make it up in volume.