View Full Version : scalable alternate energy source


cxevalo
07-10-2008, 11:40 AM
a quick google of algae will give you a great deal of information about algae and the current efforts to produce bio diesel and ethanol from it. They all seem to be looking for results in a few years, using some fairly complicated technology.

now goggle wood pellets.

Instead of all of the high tech stuff why not harvest open pond algae and pelletizing it.

There are some non trivial problems with harvesting it, it plugs any filter i have tryed almost instantly.

At present i have no idea how to make a palletizer, in a weekend with hand tools.

What i have done is scrape a handful if algae out of one of the buckets we put in the horse paddocks, and squeeze as much water out of it as i could. It formed a ferm lump and in several days dried out still a solid piece. Which tells me it will can probably be formed into pellets that can be handled with out
adding any kind of binder.

Any ideas or suggestions about harvesting and or pelletizing?

I know algae doesn't grow profuse everywhere but i live in southern Florida and about a third of this end of the state seems to be scummy pounds.

Geof
07-10-2008, 01:03 PM
Non trivial problem is an understatement.

To figure out how non trivial thoroughly dry the algae; when completely dry algae, like just about any plant material, has about the same energy pure unit of weight as petroleum or coal.

Weigh the completely dry algae and then compare this with the volume of water that you obtained the algae from. Scale this and you get an idea of the volume of water that would have to be handled to start harvesting realistic quantities of algae as an alternate energy source.

Algae have been grown on a small scale in research facilities and when their environment is enriched in CO2 and the results extrapolated to say they could be a viable source. What is being overlooked is that CO2 enrichment is not practical on a large scale and the energy consumed in processing enormous volumes of water don't seem to get detected from the potential yield.

greybeard
07-11-2008, 06:00 AM
.................Instead of all of the high tech stuff why not harvest open pond algae and pelletizing it.
.................What i have done is scrape a handful if algae out of one of the buckets we put in the horse paddocks, ...............Any ideas or suggestions about harvesting and or pelletizing?

I know algae doesn't grow profuse everywhere but i live in southern Florida and about a third of this end of the state seems to be scummy pounds.

I would agree with Geof, and I suspect that if you want to go further you'ld have to see how much algae you could grow, how quickly, and in how little water.
I'd start to think in terms of a continuous belt just under the surface of the very shallow "pond", powered by solar of course :D running under a scraper blade. The water might only have to be a thin film, but then you might have to enclose it to reduce evaporation losses.
Old spin dryers, suitably modified, make cheap centrifuges.

I'm thinking of growing watercress hydroponicaly myself, so I might try a simillar set up.

John

cxevalo
07-13-2008, 08:25 AM
Geof: you are of course quite correct, the amount of algae in the water is quite low, so you have to move a lot of water. Even when you do that seperating the algae is another challange. Is gloppy stuff that almost instantly cloggs any pass through filter.

I am trying to find a scale that i can use to measure the dry weight of algae in a gallon of water. (weigh a coffee filter , run a gallon of pond water through the filter, dry and weigh, subtract the tare). Thinking of building an optical densitometer first so i can see it that works, using the weighed samples to calibrate.

greybeard: way to go , you can always just grab a handfull and have a crest sandwich.

Joe