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Newest Energy Source — Pond Scum
An anonymous reader writes to tell us that several start up companies include one from MIT are looking at using (both natural and engineered) algae as source of bio-fuel. Since algae grows quickly and absorbs green house gases. From the article "Soybeans can give you 50 to 60 gallons of oil an acre compared to 75 to 125 gallons for canola, but algae is almost limitless because it grows so fast, so potentially you could get 10,000 gallons per acre."
A Look Back at the
U.S. Department of Energy's
Aquatic Species Program:
Biodiesel from Algae
http://www.nrel.gov/docs/legosti/fy98/24190.pdf
Actually, they have found a use for Lawyers ... as source of nutrients for Pond Scum.
Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
Wow.
This algae idea could grow on me.
The opposite of progress is congress
So, what's it like posting from 2028?
There is a great need to increase world-wide carrying capacity without impacting high biodiversity ecosystems such as the Brazilian rainforests or continental shelf fisheries, and that reduces greenhouse phenomena. There may be an economic option that uses sea water pumped to desert areas powered by the fact that ground level temperatures are much higher than temperatures at high altitudes. Indeed, it would dump greenhouse heat to space for its power while producing biodiesel, electricity, fish, fresh water, salt and real estate -- all in quantities demanded by developed-world populations -- without adding to, and possibly even sequestering, greenhouse gases.
Proposals for solar updraft towers have typically assumed that they would be single use structures: solar to electricity via heat differentials between high altitude air and ground level greenhouse-enclosed air. The resulting system has marginal economic value.
Something which would further enhance the value of the solar updraft tower power structure is to use the greenhouse area for algae ponds to add biodiesel, water, fish and salt production to the production of electricity normally envisioned.
Doing so brings the proposal from marginally viable to viable, with a net present value, primarily from live fish production, of $3.5 billion per system, thereby allowing for far higher capitalization and/or return on investment.
Let's start with just the value of algae biodiesel:
The greenhouse area required per solar updraft tower of is huge:
(pi * (5km/2)^2) ? hectares
= 1963.49 hectares
producing peak at peak 200MW via a 1km tall tower.
We now add to this the production of algae biodiesel:
The UNH estimate for algae biodiesel production is 1 quad per 200,000 hectares. Let's assume only half of the area of the solar updraft tower greenhouse would be available for production at any time (the other half would be used for ponds that buffered heat for the inner ponds, produce fish, provide additional evaporative surface for desalination and provide recreation for residential areas at the outer rim).
That gives us:
(1963.49/2)hectares/tower;200000hectares/quad ? towers/quad
= 203.719 towers/quad
Or about 200 towers per quad of biodiesel.
We can now calculate the biodiesel per tower:
7.2gallon/1e6btu;200tower/quad ? gallon/tower
= 3.5998E+07 gallon/tower
or about 35M gallons of biodiesel per year per tower.
At $2/gallon for wholesale diesel, this yields $70M biodiesel revenue per year.
Now for electrical revenue:
At an average rate of sold production only 1/2 (100MW) of peak capacity (200MW), electrical production per tower per year, is:
100MW;year ? GWh
= 876 GWh
At $30/MWh wholesale:
100MW;year;30$/MWh ? $
= 2.628E+07 $
or about $25M electrical revenue per year.
Interestingly, the biodiesel revenue is nearly 3 times the electrical revenue of a solar updraft tower!
200*200MW or 40GW electrical peak capacity is produced per quad of biodiesel.
Further that same UNH document estimates 19 quads to replace all transportation fuel in the US or 3800 towers, which would also produce 3800*200MW or 760GW or .76TW of electricity.
Current winter capacity in the US i
Seastead this.
From a quick scan - "Even with aggressive assumptions about biological productivity, we project costs for biodiesel which are two times higher than current petroleum diesel fuel costs".
If that was in 1998, then at should be very feasible with current petrol costs, especially taking into account the added value of removing CO2 from the atmosphere.
Indeed so! The 2006 inflation adjusted price in 1998 was $18 a barrel, last I checked it was three and half times this right now. In fact the average inflation adjusted price over the last 33 years is about double the 1998 price.
If the DOE algae biodiesel cost estimate is correct then it has already been on average a break-even technology for a third of a century.
Both the total world production of oil and the production of oil available for export are peaking about right now. This has been predicted for years: http://www.energybulletin.net/147.html and current studies verify this.
Thus the cost of oil is not likely to experience any significant downward trend from now on, ever.
The original article's production estimates are a bit suspect though. The 20,000 gallons of biodiesel per acre they give as the upper range of production is 47 g/square meter a day. The DOE gives a maximum annual production of 50 g/square meter of algae (not biodiesel) a day.
Still, the technology looks really good.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
You might want to actually read the article you posted in your own link. Free markets do not just fail whenever externalities exist. If that were true, capitalism itself would have failed by now. Negative externalities do tend to create "less socially optimal" situations, but that doesn't mean that market forces can't correct for them, either. I agree, however, that it seems unlikely that corporate enterprise is likely to spontaneously create a solution for global warming.
Breakfast served all day!