He really, really misses the point: what matters most is economics, not technical metrics in vacuo.
“… these values even do not take into account that more than 50% of the energy stored in the biofuel had to be invested in order to obtain the biomass (for producing fertilizers and pesticides, for ploughing the fields, for transport) and the chemical conversion into the respective biofuel.” [...] “The production and use of biofuels therefore is not CO2-neutral. In particular, the energy input is very large for the production of bioethanol from wheat or maize, and some scientists doubt that there is a net gain of energy. Certainly the reduction of CO2 release is marginal.”
In real world economics, biofuels are not energy; they are high-density liquid transport fuels. The economics make it clear: e.g., gasoline costs ten times as much as coal, per unit energy. You're paying for the chemistry, not the joules.
It matters very litte in real life, that much of the energy (cheap) is wasted; that much of the energy comes from (cheap, external) sources. If biofuels are viable, they can be seen as a conversion of energy to hydrocarbons: of (comparatively) cheap electricity and methane/hydrogen to expensive liquid fuel. Not as a primary energy source. It's the carbon that's valuable.
Farming machinery can be electric powered. Nitrogen fertilizer can be created from nuclear- or solar- powered hydrogen. And voilà, it is carbon-neutral. Nuclear electricity, solar electricity, hydrogen -- these are only marginally viable fuels (c.f. the world market for EV's; opinions may differ). Converting them to liquid hydrocarbons is a very useful thing.
> In real world economics, biofuels are not energy; they are high-density liquid transport fuels. The economics make it clear: e.g., gasoline costs ten times as much as coal, per unit energy. You're paying for the chemistry, not the joules.
Somehow, this is hard to get through people's skulls. Liquid hydrocarbons are a really potent energy storage medium with fantastic economics. (Compare a metal tank to Li-ion battery.) So long as we have need of bulldozers and heavy equipment at sites outside of fully established infrastructure, like construction sites, we will have a good use for such fuels. It's not overall efficiency that's important here. It's efficiency in a mobile context.
> Farming machinery can be electric powered. Nitrogen fertilizer can be created from nuclear- or solar- powered hydrogen. And voilà, it is carbon-neutral.
This really bothers me, and it happens all the time. Of course everything in our current infrastructure has a carbon footprint!
A large amount of the "bulldozers and heavy equipment at sites outside of fully established infrastructure" are the giant machines used to pull oil and natural gas from remote locations (tar sands, arctic and offshore oil rigs) and transport them the large distances to places inside fully established infrastructure. The need for hydrocarbons is compounding.
Similarly with biofuels, even if we are to genetically engineer more efficient plants to grow fuel, it still must be grown in a remote location, processed, and transported to places with existing established infrastructure.
In comparison, most places where people need energy already have the electric infrastructure to support it. We should be using liquid fuels in cases where it is truly necessary, not just for the short distances and minor wants of most.
We are not disagreeing. My position is that liquid hydrocarbon fuel is always going to have a specialist niche. I also think the bulk of transportation should be electric, ultimately deriving power from the sun. There's no reason to be dogmatically absolutist about energy storage technology. I say we use what works in whatever context it works. This way, we're never stuck by the disadvantages of a particular technology.
It matters very litte in real life, that much of the energy (cheap) is wasted; that much of the energy comes from (cheap, external) sources.
you are just arguing that the production of bio fuels is cheap and that hence they are economically viable. obviously you'll make a profit with selling bio fuels, but that's because the market incentives are botched and a lot of the external costs have not been internalized in agriculture. ultimately the production of bio fuels is not ecologically viable - it competes against the food production and requires significant energy for the conversion (as you say) into hydrocarbons.
If biofuels are viable, they can be seen as a conversion of energy to hydrocarbons: of (comparatively) cheap electricity and methane/hydrogen to expensive liquid fuel. Not as a primary energy source. It's the carbon that's valuable.
that doesn't make any sense, because hydrocarbons have a very small intrinsic value - the (most common) usage you derive from hydrocarbons is motion energy. and the most efficient source for motion energy is again the electric motor (which could be powered more efficiently by electricity from solar panels).
* He says the energy input is very large. I say it's reasonable for it to be so, because it's converting a cheap form of energy into a valuable one
* He says it is CO2-intensive because of the large energy inputs. I say this is just a reflection of the whole energy economy being CO2-intensive; that in principle the inputs can be CO2-free, and so biofuels can be CO2-neutral. (And they unique in this aspect; there is no other way to make CO2-neutral hydrocarbons, short of chemically scrubbing CO2 from the atmosphere.)
Comments
He really, really misses the point: what matters most is economics, not technical metrics in vacuo.
“… these values even do not take into account that more than 50% of the energy stored in the biofuel had to be invested in order to obtain the biomass (for producing fertilizers and pesticides, for ploughing the fields, for transport) and the chemical conversion into the respective biofuel.” [...] “The production and use of biofuels therefore is not CO2-neutral. In particular, the energy input is very large for the production of bioethanol from wheat or maize, and some scientists doubt that there is a net gain of energy. Certainly the reduction of CO2 release is marginal.”
In real world economics, biofuels are not energy; they are high-density liquid transport fuels. The economics make it clear: e.g., gasoline costs ten times as much as coal, per unit energy. You're paying for the chemistry, not the joules.
It matters very litte in real life, that much of the energy (cheap) is wasted; that much of the energy comes from (cheap, external) sources. If biofuels are viable, they can be seen as a conversion of energy to hydrocarbons: of (comparatively) cheap electricity and methane/hydrogen to expensive liquid fuel. Not as a primary energy source. It's the carbon that's valuable.
Farming machinery can be electric powered. Nitrogen fertilizer can be created from nuclear- or solar- powered hydrogen. And voilà, it is carbon-neutral. Nuclear electricity, solar electricity, hydrogen -- these are only marginally viable fuels (c.f. the world market for EV's; opinions may differ). Converting them to liquid hydrocarbons is a very useful thing.
> In real world economics, biofuels are not energy; they are high-density liquid transport fuels. The economics make it clear: e.g., gasoline costs ten times as much as coal, per unit energy. You're paying for the chemistry, not the joules.
Somehow, this is hard to get through people's skulls. Liquid hydrocarbons are a really potent energy storage medium with fantastic economics. (Compare a metal tank to Li-ion battery.) So long as we have need of bulldozers and heavy equipment at sites outside of fully established infrastructure, like construction sites, we will have a good use for such fuels. It's not overall efficiency that's important here. It's efficiency in a mobile context.
> Farming machinery can be electric powered. Nitrogen fertilizer can be created from nuclear- or solar- powered hydrogen. And voilà, it is carbon-neutral.
This really bothers me, and it happens all the time. Of course everything in our current infrastructure has a carbon footprint!
A large amount of the "bulldozers and heavy equipment at sites outside of fully established infrastructure" are the giant machines used to pull oil and natural gas from remote locations (tar sands, arctic and offshore oil rigs) and transport them the large distances to places inside fully established infrastructure. The need for hydrocarbons is compounding.
Similarly with biofuels, even if we are to genetically engineer more efficient plants to grow fuel, it still must be grown in a remote location, processed, and transported to places with existing established infrastructure.
In comparison, most places where people need energy already have the electric infrastructure to support it. We should be using liquid fuels in cases where it is truly necessary, not just for the short distances and minor wants of most.
We are not disagreeing. My position is that liquid hydrocarbon fuel is always going to have a specialist niche. I also think the bulk of transportation should be electric, ultimately deriving power from the sun. There's no reason to be dogmatically absolutist about energy storage technology. I say we use what works in whatever context it works. This way, we're never stuck by the disadvantages of a particular technology.
It matters very litte in real life, that much of the energy (cheap) is wasted; that much of the energy comes from (cheap, external) sources.
you are just arguing that the production of bio fuels is cheap and that hence they are economically viable. obviously you'll make a profit with selling bio fuels, but that's because the market incentives are botched and a lot of the external costs have not been internalized in agriculture. ultimately the production of bio fuels is not ecologically viable - it competes against the food production and requires significant energy for the conversion (as you say) into hydrocarbons.
If biofuels are viable, they can be seen as a conversion of energy to hydrocarbons: of (comparatively) cheap electricity and methane/hydrogen to expensive liquid fuel. Not as a primary energy source. It's the carbon that's valuable.
that doesn't make any sense, because hydrocarbons have a very small intrinsic value - the (most common) usage you derive from hydrocarbons is motion energy. and the most efficient source for motion energy is again the electric motor (which could be powered more efficiently by electricity from solar panels).
I'm having trouble following your point. He says the "input is very large" and you're arguing that the input doesn't have to be large?
More than one thread:
* He says the energy input is very large. I say it's reasonable for it to be so, because it's converting a cheap form of energy into a valuable one
* He says it is CO2-intensive because of the large energy inputs. I say this is just a reflection of the whole energy economy being CO2-intensive; that in principle the inputs can be CO2-free, and so biofuels can be CO2-neutral. (And they unique in this aspect; there is no other way to make CO2-neutral hydrocarbons, short of chemically scrubbing CO2 from the atmosphere.)
Yes, the input is large (if you accept his numbers), but the inputs are stationary power and the output is portable power.