Xeriar wrote:We aren't necessarily limited to only the photosynthetically active spectrum common to plants. There are ways to harvest energy from other portions of the spectrum (halobacteria, for example).
GM-ing stuff isn't as easy as it sounds, especially if you want to modify complex processes like photosinthesis. You cannot just add a gene or two like what the people did in the article to have diesel-producing bacteria.
If you make a mix of different algae then you end up with an efficiency difficult to calculate, but not particularly better.
You could, alternately, divide eight billion by the number of seconds in a year to get the figure I was using.
8,000,000,000/31,536,000 = ~254 watts.
I'm too lazy to check your math

, but I'm pretty sure you made some mistake. There is a significant difference in our results.
I calculated that with 100% efficient conversion you would still need 17'000 km2 of surface when you said 2'300 km2 would suffice.
In order to have efficient growth, you need carbon sources.
Like carbon dioxide? It is also conveneintly mixed with oxygen (that the algae also need) in the atmosphere. Then you just have to throw chemical fertilizer at them. It does wonders for algae in running water.
We do not need to replace 100% of our oil production.
Of course. We are doing it only for kicks.
So far nothing is viable beyond fossil oil. So if this specific biodiesel-producing thing goes up it will still reamin vastly cheaper than any other way of biodiesel production. Thus won't be a particularly good choice to produce 30% or even more of the world's needs using inefficient methods. Unless you assume all other methods to be developed enough to become viable too.
We're still going to be producing 60-70% of what we currently need twenty years from now, conventionally.
Yup, but will it be sold at what price? Consider that the unrest in most countries producing oil and gas may end up with lots of Free Democracies (TM) that will not be so eager to keep the prices unreasonably low as the brutal assassins that ruled the same countries for personal gain before.
Also, by just increasing efficiency in ways
we know already, we can get something like a 50% reduction of oil consumption, so we don't even need to waste time with algaes and crap if we are doing it just "to supplement oil production".