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Mass Algae Culture

Micro algaes present the best option for producing Bio Fuel such as biodiesel in quantities sufficient to completely replace petroleum. While traditional crops have yields of around 50-150 gallons of biodiesel per acre per year, algaes can yield 10,000-40,000 gallons per acre per year. Some other studies have looked into designing raceway algae ponds to be fed by agricultural or animal waste, while other research is now investigating the possibility of using the algae mush (what is left after extracting the oil) as a fertilizer.

The Sola Roof approach will produce the algae in the transparent building envelope and the exposure to PAR radiation occurs as the nutrient liquid carries the algae over the roof in a thin film flow and then the algae bloom will take place in the biomass culture tank that is part of the Liquid Thermal Mass system located at the ground level of the structure. This enclosed method is much more productive because a CO 2 enriched culture environment is maintained. This results in an effective Global Warming Solution. Our most recent development work is progressing in Norway, where Bio Digester leachate will be used to grow Energy Crops? that integrates aquaculture of Water Weeds? and Algae.

Thus we are convinced that the sustainable future will be based on a clean Carbohydrate Economy rather than a Hydrogen Economy.

Questions from LucasGonzalez; answers by Solaroofguy

My questions:

  1. Algae: experience (contamination with diatomeas, silice, ask George Chan zeri.org)

At the NREL place they explicitly mention (in a pdf report) "temperature control" as an important step towards achieving predictable maximum productivity. They mention 50 grams per square meter at most, which adds up to say (a maximum of) 50 grams x 5000 square meters = 250 kilos of algae each day. If that in turn means say 50 liters of oil a day (just guessing) (plus water, plus compost), doesn't look like much (oil). Worth trying, of course.

The NREL studies are politically controlled and not very reliable. With very promising results the whole program was terminated around 1996 and the potential has been buried. I will email you the Biography of reseach contracts that I found - it would take some time to sift through. The temperature of the liquid culture is very important because if it is above 20C (like hydroponic systems also) the amount of CO 2 that can be disolved is low and this will limit growth. That is why the cold ocean waters are so rich in algae and the tropical waters are less productive. Oil from palm yields about 2000 pounds per acre and other crops less than 1000 (peanut, sunflower seed etc) while the pond systems have produced upto 15,000 pounds per acre. I believe we could produce about one pound per square foot of building envelope per year. The per day yield will not appear impressive but it is orders of magnitude larger than any other energy crop. - Rick

Just let me translate [1] a bit, imagining a 5000 square meter greenhouse and using kilograms:

  • 2000 pounds per acre and per year = 907 kg per acre = 1134 kg per 5000 square meter per year (this is for palm oil)
  • 1 pound per square foot and per year = 4983 g per sq meter = 24915 kg per 5000 square meter per year (which is 22 times as much if my maths are correct (yes, this is the algae oil yield) (and which means the consumption of:

[1] I've used google "acre" (etc):

  • 1 acre = 4 046.85642 m2
  • 1 pound = 453.59237 grams
  • 1 foot = 30.48 centimeters (11 sq feet = 1 sq meter)

We can also use Flemming Funch's http://www.opentopia.com/tools/unitconversion.html

  1. Crops: experience
    • I do have some data but it is all hard copy and I need to scan and OCR it - perhaps next week - this will be a task in the development of my Almeria Project
  2. Ultraviolet filter: uv good for "sterility", ask Rick
    • Our cover materials are quite transparent to the UV but block the shorter wave UV (called UV A & B?) and the Liquid Cooling and Liquid Bubble Insulation is transparent to the UV (like cloud cover) and very superior to the white paint that is put on the standard greenhouse as a shading method.

Bobby here - More recent research has shown the ability to keep the algae culture alive for more than a year with no contamination problems.

The better specie produce about 50% lipid, so you may be underestimating lipid production. As a counter example,Sprulina produces only 4 to 7%, so specie selection is important. Bobby

Questions from Bob Allen; answers by Solaroofguy

Green House Gases?: A Distributed Resource for Distributed Solar Conversion to Bio Mass? and then to Bio Fuels?

Capture of the GHG at the central power plant is part of the cost of environmental protection. Some advanced coal technology power cycles will produce almost pure CO 2 in the stack. They are not feeding air to the combustion chamber. They use oxygen limited pre-combustion heat "reforming" that releases oxygen from the fuel itself in a closed cycle. These systems are designed for total capture of the CO 2 so that it is a clean energy process. They will definitely need a means for "sequestration". Bleeding the CO 2 into the atmosphere surrounding a tree plantation will in fact sequester some of the CO 2 as is provable by a 40% greater rate of growth (biomass). They would only get to claim the incremental biomass production as a provable CO 2 sink. Because these rates are too low and the process is inefficient (most of the CO 2 is lost into the atmosphere) there is interest in any other options for sequestration. The industry giants are looking at injection of the CO 2 into the deep ocean and into exhausted oil fields and deep mines.

Yes, but how much (sequestration)? Economically it may work but will it really produce energy and really reduce release of CO 2 ?

In the algae culture proposal the CO 2 is not able to escape to the atmosphere. The culture takes place in a sealed roof cavity space (or tubing on the ground in the systems Mike describes) so that no CO 2 can escape. It is completely metabolized and as it is thus consumed more is injected for take up by the biomass growth. In a sealed commercial greenhouse - a mature tomato crop will deplete the CO 2 from 900 PPM to 150 PPM in about ten minutes. Therefore, if you don't ventilate to bring in atmospheric CO 2 - you must have an "artificial" CO 2 enrichment system or else in a few short minutes there would be no growth going on at all because of CO 2 starvation.

Large projects could be sited near to thermal power plants and clean (scrubbed) CO 2 could be piped at minimum expense into these projects. On the other hand bottling the GHG is a mitigation cost incurred by central production of energy Vs distributed production. The power generator has to factor this into his costs (I could not believe that it would be more then 5% of costs - which is similar to the cost of transporting in the fuel). So you transport in the fuel and you transport out the GHG. If this is not so economic then it will simply accelerate the adoption of distributed power together with district heating and cooling systems. In this case the very clean stack gases are released into the closed atmosphere algae (and plant) biomass systems where the CO 2 is reconstituted using solar energy into a Bio Fuel and this is fed directly back to the community based Mirco Turbine? power plant.

Concerning the sequestration of CO 2, how much of a charge of CO 2 do you think would actually be sequestered? I'm guessing only a few percent, the remainder, after much handling would escape back to the atmosphere.

In the closed cycle systems that I am proposing 100% of the CO 2 produced can be recaptured in the form of a Bio Fuel. Remember that there are also other important by-products as well. Also the energy not intercepted by the Phytotechnology system can pass through the transparent roof and be utilized in the form of day lighting and the low-grade thermal for space heating. I can also envision combined Phyto Technology? and Photo Voltaic systems for optimizing solar conversion.

It is not usually a good idea to look for 100% from one system. If we combine several good systems and integrate them to lower the cost of the total system while adding the various efficiencies of each system we can move the total utilization up will lower the incremental costs for each of the systems.

If the power company is going to go to the trouble to capture and transport the gas as an offset to GHG's they could only discount that amount that is actually sequestered.

I can say with confidence that the captured CO 2 can be entirely converted to biomass with no escape to the atmosphere and that this process will take place at very much enhanced rates as compared to the "natural open-air pond culture" of algae, which achieved 3.5 pounds of oil per square foot of pond surface area per year. How much conversion per area - given the greater advantages of the Sola Roof system - I would estimate production to be very significantly higher. Yield could be over one gallon of oil per square foot of roof area per year.

I will be inviting the University of New Hampshire and other to could step in here with some help to get a handle on the probable rate of biomass generation. Also, it would be great to get clearer picture of what clean combustion technology would be possible. I have heard about the Capstone Mirco Turbine? being used in distributed power situations. Perhaps someone with experience in community power systems could comment.

Further Questions:

What would be the possibility of firing these machines with Bio Fuel (vegetable oil)?

What is the stack gas? In natural gas feed units how pure is the stack gas?

Could it be fed directly into a closed atmosphere greenhouse? (This is what the commercial greenhouse people do with their "CO 2 Generators")

Would any projects out there consider a community integrated greenhouse (solar designed of course!) to work off such community generated GHG so that they could be CO 2 neutral?

Bob Allen, Professor of Chemistry Arkansas Tech University