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[smjjames]

If you want to minimise ecological damage through farming, it certainly would be a good first step to stop with livestock except where the ground is unsuitable for crops, but grass can grow there. Something like 10-20% of energy is lost per step of the food chain (excluding the first step (plant to animal) because of how much energy is indigestible. That raises it to 80-90%) and the methane they produce is fairly bad too, then probably minimising fertilisers and pesticides due to the fact their effects go well beyond the immediate area around the field.

You're moving goalposts again. We're talking about efficient farming, not less farming.

SOmetimes in order to make things more efficient, you have to lessen things.

[MarcAFK]

As I recall one of them most efficient crops at turning sunlight into burnable carbs is sugarcane, and they're only about 15% efficient. Whoever thinks biofuels are a good idea is insane.

[Bohandas]

Technically the main thing that distinguishes them from fossil feuls is the elimination of the extremely time consuming intermediate step in which plant matter is converted into coal and/or oil.

EDIT:
Now, the argument that both are bad ideas is a bit more plausible.

[Descan]

Biofuels are only good if you use non-edible material in either non-farming locations (like, that you can't use to farm. Mountain sides, oceanic algae farms, etc) or the non-edible material from edible foodstuffs, like wheat chaff or corn stalks.

[MarcAFK]

Except returning the nonedible material to the ground is important for keeping soil healthy. Which is a completely different conversation, but basically even the lowest efficiency solar panels are about as efficient as food crops and don't need to be replanted, reharvested, and reprocessed every year. The arguments against solar are mostly the energy needed to make them, the short lifespan, the use of increasingly rare materials for higher efficiency panels, and the space required.  But compared to food crops it makes sense as these have the same drawbacks. 

[Baffler]

Solar panels, even modern ones, aren't terribly efficient as far as energy put in for their lifespan, and they're only viable for commercial generation in a pretty limited area. The future of energy lies in nuclear power, and possibly hydrogen for cars.

[Frumple]

... wait, which solar? I thought the reflect-y version actually did pretty good?

[mainiac]

Solar panels, even modern ones, aren't terribly efficient as far as energy put in for their lifespan, and they're only viable for commercial generation in a pretty limited area. The future of energy lies in nuclear power, and possibly hydrogen for cars.

Oh neat, it's a time traveler from 10 years decades ago!  Quick, before you return to your time let me tell you that you want to bet on Germany to win the 2014 World Cup!  Also the star wars prequels will suck.

30 seconds of googling gives a pretty solid answer if you want to see what the energy payback period actually looks like today:
http://cleantechnica.com/2013/12/26/solar-energy-payback-time-charts/

[Sheb]

Re: buifuels, you also have algae in tanks. They of course need more infrastructure that standard crop, but the yield you can guess are pretty insane. On the order of several hundred tons of oil per hectare.

[miauw62]

Solar panels, even modern ones, aren't terribly efficient as far as energy put in for their lifespan, and they're only viable for commercial generation in a pretty limited area. The future of energy lies in nuclear power, and possibly hydrogen for cars.

Or fusion, with any luck.

[10ebbor10]

I must note that  what you're linking to is a paid advert site for green power. Neutrality may be questioned. (And is. Now. By me.)

Anyway, a solar panel taking 3 years for energy payback, and lasting 30 years, only has an EROEI of 10, which I must say is not terribly efficient. (And that is unbuffered. Buffering makes it worse*).

Anyway, continuing on, it's all about the price. And then you see that solar really isn't close.

http://en.openei.org/apps/TCDB/

Note: the app makes some strange default assumptions, such as overestimating capacity factors, and placing the lifetime of all energy sources at 30 years. (I advice you to set it to scatter mode, as then you can see the various assumptions made for each study. I mean, the lowest cost solar PV estimates all assume like 30% CF, which I'm quite sure might be physically impossible.)


*Neutrality warning : Made by German nuclear physicists.

[Sheb]

An EROEI of 10 is not that bad actually. Biodiesel is at ~1.5, shale oil is at 6. Of course, the real photovoltaoic EROEI is closer to 7 than to 10.

[10ebbor10]

An EROEI of 10 is not that bad actually. Biodiesel is at ~1.5, shale oil is at 6. Of course, the real photovoltaoic EROEI is closer to 7 than to 10.

Biodiesel and shale oil aren't on my list of reliable future energy sources either.

[mainiac]

We've argued over this before, I dont see the need to do so now.  I was just poking fun at the ridiculous statement that solar is inefficient from an energy standpoint.  That hasn't been true in a long, long time.

[MonkeyHead]

Inefficiency is kind of irrelevant when there is ample enough abundance.