solar panels vs biodiesel

[dcb]

Just looked into this a bit, this site says solar panels take maybe 1/5 the amount of land as biodiesel when it comes to pushing a car around:

Fat Knowledge: Algae Biodiesel vs. Solar Panels

[Lug_Nut]

How much of the solar panel waste product remains to be burned as carbon "neutral" fuel for external combustion processes, like steam generation to run electric generators? The fact that the dried algae remaining after oil extraction still has energy content should not be overlooked.
Using what are termed "food crops" for biodiesel doesn't seem to account for the fact that very little of the "food" is lost when maximizing biodiesel production, mainly because the food is of much higher value. The biodiesel is a secondary by-product of what would often otherwise be waste from food and feed production. Food caloric energy AND biodiesel energy are above the current (pun intended) state of photovoltaics.

Please keep in mind that solar panels also contribute to micro-desertification by interrupting the photosynthesis in the plant matter under the panel.

The example VW costs how much? The example Tesla how much?
How about I buy half that technology today.
I have VW TDI that average 35 ('05 Passat, $15K) and 45 (97 Passat, $4k) mpg. What pure electric can I buy today that will provide me with half the Tesla's performance and range?
I decided I wouldn't wait for some technological breakthrough allegedly coming in some continually receding future time frame. I decided to do the best I could right now, and for me the logical answer was, and remains: Biodiesel.

[dcb]

Originally Posted by Lug_Nut

The fact that the dried algae remaining after oil extraction still has energy content should not be overlooked.

I know very little about this stuff currently, glad you bring these points up actually. So I don't know how to quantify this, how much extra land does it take to reliably dry out the algae from a given amount of land? And how much extra energy does it provide? Presumably it would yield more energy than just growing more algae on that land.

Originally Posted by Lug_Nut

Using what are termed "food crops" for biodiesel doesn't seem to account for the fact that very little of the "food" is lost when maximizing biodiesel production, mainly because the food is of much higher value.

I didn't see any obvious sources for that data, do you have a link? I mean wvo, sure, but I don't know anything about pre-consumer foods. The other side of the coin is that biodiesel still has to come up with some ethanol and deal with some glycerine and left over biomass and further drying.

Originally Posted by Lug_Nut

I decided I wouldn't wait for some technological breakthrough

Definitely an improvement over petrol. You are basically solar powered at that point, with the performance and initial cost of an ice.

[ShadeTreeMech]

solar panels, at best, convert what, 12-15% of the available energy into electricity? And any internal combustion engine will outdo an electric car in the realm of range and refueling (except Honda's FCX Clarity, a stunning vehicle if you live in California near a hydrogen refueling station) And to increase a battery powered vehicle's range, you have to increase its weight substantially.

The best happy medium? I think a diesel hybrid. But instead of adding a battery large enough to power the vehicle several miles on electric power alone, add a smaller battery which allows easy restart from the stoplights but is not so heavy to shoot itself in the foot with a heavy payload. Plain ole diesel cars can get crazy mileage and can run on biodiesel, or even veggie oil when using a dual fuel setup.

However, the promises of more efficient gas powered engines are coming true. The direct injection gas engines are showing good promise, and there is the diesotto engine being designed by mercedes
Mercedes-Benz unveils DiesOtto - the “future of the gasoline engine”

It basically says it takes a 1.8 L inline 4 cylinder engine with 238 hp and 295 ft/lbs torque and puts it in a mercedes s-class which weighs nearly 4500 lbs and a Cd of .26 to .28. Depsite all this, it still gets 40 mpg- in a gas driven luxury car.

The Honda FCX Clarity might be an awesome car, but this Diesotto engine is hard to ignore.

[ShadeTreeMech]

ps you don't need ethanol if you burn WVO straight and skip the step and effort of turning it to biodiesel

[JacobAziza]

OR?
Why or?
I run the truck on biodiesel.
I disconnected my alternator (along with every other parasitic engine load) and put in a solar panel.

More relevant:
Most of the biodiesel available today comes from waste vegetable oil, which means it involves no land at all to produce.

However there is no where near enough waste oil to fuel this countries rate of consumption.

But then again... same goes for any alternative energy. I don't think the solution is going to come from any technology.

Look what happened with hybrids: developed to increase efficiency, it was only a few years until it was adopted to add power to sports cars and SUVs.

The only long-term solution will be for us to cut back on consumption.
In other words: Not bio nor electric. Bicycle.

[groar]

All renewable energies have cons. Bio has lower efficiency than panels, but when only wastes are used then it is cool. Panels prevent bio under them, but how many feet square are wasted to bio ?

Anyway imho I think we need several renewable energies to get rid of fossil fuel.

Denis.