Algal biofuels - the oil of the future? Or not...

[auroraglacialis]

A culture of insanity: Algaeworld / Die Algenwelt

The researchers found that 21 billion gallons of algal oil, equal to the 2022 advanced biofuels goal set out by the Energy Independence and Security Act, can be produced with American-grown algae. That's 17 percent of the petroleum that the U.S. imported in 2008 for transportation fuels, and it could be grown on land roughly the size of South Carolina. But the authors also found that 350 gallons of water per gallon of oil -- or a quarter of what the country currently uses for irrigated agriculture -- would be needed to produce that much algal biofuel.

Whew - amazing 17% of the petroleum "needed" and all it takes is an increase in water use by another 1/4, and covering a whole US state (albeit a smaller one) with algal farms...To be fair, the also try to work with wastewater and oceanwater to lessen the impact and actually find a proper use for wastewater, but there are no numbers yet on how much that can provide.

But evaporating water is a potent greenhouse gas - no matter where the water came from. And also the "spent" water has to go somewhere - it potentially is salty due to the evaporation and may contain additives used for growing these algal monocrops. Oh and of course they will want to use GMO algae and large scale nanotechnology for that. They do not mention how much energy is needed to keep the pumps running and cleaning the ponds and all that - this may reduce the energy gain...

Looks like at least land-based, open pond algal biofuels are not really a solution to anything. Other models include closed ponds, tubes (very expensive) or ocean based (giant floats) systems, but given the size of this, these seem less feasible - economically and technically.

[Human No More]

All biofuels are a huge placebo... algae are better than most in that they don't take up areas needed for actual food... but this is typical of trying to replace sources of oil instead of trying to replace the oil itself.

[Pa'li Makto]

We need to further our technology so the reliance on oil is gone. Algae biofuel production wouldn't be able to cope with the massive demand that the developed countries would place on it.

[applejuice]

Before going green, we need to make our machines and processes more efficient. As many of you know, a gasoline engine is, typically, 14% efficient; a Diesel engine, at most, 50%. Before starting to throw food or dedicating enormous extensions of land to make biofuels, we need to make sure that the product will be efficiently consumed. Unfortunately, there's no way to improve the efficiency of the gasoline or diesel engine. Thermodynamics predicts that those efficiencies are the highest we will reach (or we will have to change the laws of physics, but that's impossible). Replacing oil will take decades, it will certainly happen.

[Fosus]

Originally Posted by applejuice

As many of you know, a gasoline engine is, typically, 14% efficient; a Diesel engine, at most, 50%. Before starting to throw food or dedicating enormous extensions of land to make biofuels, we need to make sure that the product will be efficiently consumed. Unfortunately, there's no way to improve the efficiency of the gasoline or diesel engine.

This, It would be more efficient to have electric motors and create electricity out of the oil ..

[applejuice]

Yes, going completely electric is the way of the future. Electric motors are 85 to 95% efficient in transforming electric power into mechanical power. Electronics makes the electric motor a very versatile machine, but there's still a disadvantage: the batteries.

[Human No More]

Originally Posted by applejuice

Yes, going completely electric is the way of the future. Electric motors are 85 to 95% efficient in transforming electric power into mechanical power. Electronics makes the electric motor a very versatile machine, but there's still a disadvantage: the batteries.

Indeed. Batteries are the main reason that electric cars will never work with current technology, when a charge is anywhere from 8-12 hours, while filling a car with petrol is maybe 5 minutes maximum. Future batteries are being developed which are capable of charging to 80% in ~3 minutes as well as having a much smaller capacity loss over time (the other big problem - many existing electric cars' range will drop to just over half over a few years depending on usage), which would be a solution, but these will most likely require specialised power systems (although as they become more common, that becomes less of a problem) and do not yet exist in anything more than concept and very early prototypes. Once they are at a usable state though, then the world can move to mostly electrical.

[auroraglacialis]

Originally Posted by applejuice

Electric motors are 85 to 95% efficient in transforming electric power into mechanical power.

... but generating electricity is very inefficient. Usually below 50% IIRC for the better power plants, more like 30%. Some solarthermals are at 50%, solarelectric are below 10%. Then transporting electricity (landlines) and storing it again (batteries, hydrogen) is inefficient. Overall, this is not at all more efficient really.

Originally Posted by Human No More

Batteries are the main reason that electric cars will never work with current technology, when a charge is anywhere from 8-12 hours, while filling a car with petrol is maybe 5 minutes maximum.

I think that is no reason to not do this at all. There is a very simple solution to it and that is exchangeable batteries. Just like you have several sets of batteries for your video camera or mp3-player or torchlight, you'd simply buy a full battery and return the empty one. Of course that is then not as easy as plugging the car into the wallplug at home, but the exchange could be fast and the batteries could be exchanged and recycled properly easily once their lifetime is over. It would require a standardization of battery sizes and connectors and some sort of mechanics at gas stations to replace the battery, but that is no technological problem - if anything it is one of design, regulations, standardization and acceptance. Most likely, each car manufacturer will instead produce their own batteries with own voltage and shape and connectors and at different places in the car and it sells easier if you can charge the car at home and do not need an infrastructure of refill stations that would have to be set up (though that could be combined, also - make the batteries exchangeable AND allow for homebased recharge).

The problem I see more is that using even more electricity will require massive amounts of new power plants to be built, more landlines and such. Also, the efficiency is a problem (as I said above). And to that adds the problem of getting Lithium and other materials like REEs for the huge amount of batteries and electric motors. All this has to be mined and processed and manufactured, which also costs a lot of energy and produces the usual problems with mines and mine processes. It may be a way to keep cars going, but it does not really deserve the label "green" or "clean" IMO. I think a lot more is gained if the number of cars is reduced, e.g. by easy car sharing and public transport or eliminating the need for too much transport. There is a neat project here locally that wants to put cars in the streets and you can with a membership card just rent it on the spot for a low price and leave it within the city afterwards. The organization then distributes them if they are not evenly distributed. If this is done with electric cars, at least the number of batteries would decrease.

A side fact by the way: Did you know where all the sulfur from the de-sulfurized gasoline goes to? It is dumped into the tanks of large intercontinental ships, who burn it over the open sea. So we do not have acid rain anymore on land, but the stuff just was exported to the oceans. And the 15 largest ships in the world produce as much sulfur emissions as all the land based transportation with cars together. Ugh!

[applejuice]

Originally Posted by auroraglacialis

... but generating electricity is very inefficient. Usually below 50% IIRC for the better power plants, more like 30%. Some solarthermals are at 50%, solarelectric are below 10%. Then transporting electricity (landlines) and storing it again (batteries, hydrogen) is inefficient. Overall, this is not at all more efficient really.

It depends on the type of generation. For thermal cycle generation, common efficiencies rank between 45% - 60% (for the combined thermal cycle). That's because the generator is attached to a thermal machine, and thermal machines follow Thermodynamics. If the generation is hydroelectric, the efficiencies rank from 80 - 90% (the bigger, the better). In my experience, you loss about 4 - 6% of generated power in the transmission line, add to that the transformers, typically 85% (the bigger, the better).
Let's make numbers then:
Hydroelectricity (large facilities > 5 MW)
Power available at consumer tap = Power at the turbine input x 0.90 x 0.85 x 0.95 x 0.85
= 61.77 % of power at the turbine input (that's the power that water is transferring to the machine).
Now, for thermal:
Power available at consumer tap = Thermal power at the beginning of the cycle x 0.6 x 0.85 x 0.95 x 0.85
= 41.18 % of power at the beginning of the cycle.
Storing that power in Lithium batteries is, nominally, 85% efficient. So, overall we have efficiencies of:
Hydro
.67 x .85 = 56%

Thermal
.41x.85 = 34%

Comparing that to the Otto cycle, electricity beats it by more than twice its efficiency, the only real competitor is the Diesel cycle. Coal powered electricity plants have efficiencies of 30%. So, it depends from where you are getting your electricity.

I think that is no reason to not do this at all. There is a very simple solution to it and that is exchangeable batteries. Just like you have several sets of batteries for your video camera or mp3-player or torchlight, you'd simply buy a full battery and return the empty one. Of course that is then not as easy as plugging the car into the wallplug at home, but the exchange could be fast and the batteries could be exchanged and recycled properly easily once their lifetime is over. It would require a standardization of battery sizes and connectors and some sort of mechanics at gas stations to replace the battery, but that is no technological problem - if anything it is one of design, regulations, standardization and acceptance. Most likely, each car manufacturer will instead produce their own batteries with own voltage and shape and connectors and at different places in the car and it sells easier if you can charge the car at home and do not need an infrastructure of refill stations that would have to be set up (though that could be combined, also - make the batteries exchangeable AND allow for homebased recharge).

That's what Tesla Motors is trying to do. To standardize the batteries, so one can exchange them easily.

The problem I see more is that using even more electricity will require massive amounts of new power plants to be built, more landlines and such. Also, the efficiency is a problem (as I said above). And to that adds the problem of getting Lithium and other materials like REEs for the huge amount of batteries and electric motors. All this has to be mined and processed and manufactured, which also costs a lot of energy and produces the usual problems with mines and mine processes. It may be a way to keep cars going, but it does not really deserve the label "green" or "clean" IMO. I think a lot more is gained if the number of cars is reduced, e.g. by easy car sharing and public transport or eliminating the need for too much transport. There is a neat project here locally that wants to put cars in the streets and you can with a membership card just rent it on the spot for a low price and leave it within the city afterwards. The organization then distributes them if they are not evenly distributed. If this is done with electric cars, at least the number of batteries would decrease.

A side fact by the way: Did you know where all the sulfur from the de-sulfurized gasoline goes to? It is dumped into the tanks of large intercontinental ships, who burn it over the open sea. So we do not have acid rain anymore on land, but the stuff just was exported to the oceans. And the 15 largest ships in the world produce as much sulfur emissions as all the land based transportation with cars together. Ugh!

As mentioned above, the bigger, the better. Efficiency is improved when the needed quantities of power are big, real big. There are ongoing projects involving Ultra High Voltage transmission lines expected to improve transmission efficiency. New materials are being developed for better transformer efficiency and the distributed generation schemes are emerging as a competitive alternative to the centralized generation (which also are expected to improve efficiency). The ideas that you mention will certainly make its way to the industry and regulatory entities. Stop using the car if there's public transportation, turn off the lights you're not using, unplug the things you don't use, etc. Many small things that most of us can do can also make the difference, globally and in our pockets.

[auroraglacialis]

Originally Posted by applejuice

So, overall we have efficiencies of:
Hydro
.67 x .85 = 56%

Thermal
.41x.85 = 34%

Comparing that to the Otto cycle, electricity beats it by more than twice its efficiency, the only real competitor is the Diesel cycle. Coal powered electricity plants have efficiencies of 30%. So, it depends from where you are getting your electricity.

Most electricity currently comes from coal. Hydropower can never fill the demand. I do not know where you get that number for the efficiency for Otto engines - it is about twice as much as you say and about 2/3 to 3/4 of Diesel, AFAIK. That would be around the 34% you calculated for "Thermal" (what exactly are you referring to there if you do not mean coal?) and way above what would come out if you use coal.
So electric cars are indeed wasteful, but of course some things speak for them, like that oil is running out.

As mentioned above, the bigger, the better. ... the distributed generation schemes are emerging as a competitive alternative to the centralized generation (which also are expected to improve efficiency). The ideas that you mention will certainly make its way to the industry and regulatory entities.

That sounds kind of contradictionary...

In any case, this all would require huge investments in terms of money, energy and resources and probably there are not enough resources availabe to make this happen for all the 7 bil people on the planet.
In times of economic crisis, I am not sure if there will be the political will, money and determination to make all this happen. Technically it may be possible though I do not think that this is really sustainable or a good way to go (electric cars still need toxic fluids, metals, a lot of copper and lithium, roads, energy)

Stop using the car if there's public transportation, turn off the lights you're not using, unplug the things you don't use, etc. Many small things that most of us can do can also make the difference, globally and in our pockets.

Yeah, little things are little though. You may drop the energy input of the couontry by a percent or two if you turn off lights and such, but somehow I think there are big pieces of the pie that have to be adressed. As in water consumption which is largely contributed by industry and agriculture, same is happening with energy. Most energy is not used in private households. Certainly doing all these little things will help though, just they will not solve the big scale problem unless everyone does them and everyone does a lot more. And unless industry and agrobusiness also start to cut down on consumption.

Originally Posted by Human No More

Battery exchange and standardisation is a valid solution, but the infrastructure....

Oh certainly to set all this up, it would require an enourmous effort and I doubt it will happen. I was just pointing out that the speed of loading batteries - a technical problem that is solvable - is not what really will stop such technologies to get a hold fast.

Of course, even if such a system was fully implemented today, then a battery small enough to be interchangeable without removing a significant amount of the internal structure to access it would only be enough for 10-20 miles.

I do not understand - you could either use larger batteries that have to be changed with a machine and not by manually lifting it out - or you could put in a dozen of the smaller ones, easily accessible in some way. These are technicalities.

* Exchange load would not be equal between areas, and unless stocks were huge and there was an extensive system to move them around, areas would face over-or under-supply of batteries as people move around.

That I also do not understand - you always return one battery in exchange for a new one. Like camping-gas bottles. And as the exchange stations could recharge the batteries themselves, the only reason for them to be transported would be for recycling. Of course areas with higher demand need larger stocks or more powerful rechargers. Again, this is all within the technical possibilities, the reason it will not happen are sitting in many other places.

over here and in many other countries, windfarm operators actually sell their produced energy below cost due to the nature of baseload systems meaning that there is often very little demand for it when it is available thanks to its intermittent nature, and they make their actual profit from subsidies and not energy

Well, one of the major obstacles towards using these intermittent energy sources is that the base load is fulfilled by plants that cannot adapt quickly. If they would be able to shut down when wind comes online, that would be a lot better then. This is why the current plans for Germany include the use of hydropower for storage of energy (as it is a way of generating power that is highly adaptable) and to use natural gas, geothermals or air pressure storage to fill in the gaps. What is the worst option is a baseload by plants that can not change their output at all - like nuclear, but also coal. A energy generation system that includes intermittent sources HAS to complement the intermittent sources with quickly available and dynamic sources. It has to be a highly dynamic network.

Regarding subsidies - all energy is subsidized usually in some way or another (and if it is only a reduced tax, cheap government loans or government financed R&D). In Germany, coal is subsidized to keep the coal workers in their jobs, nuclear is heavily subsidized, there are few taxes and the state paid for a lot of the R&D and the research on the waste storage, solar/wind/biogas is subsidized by giving the owners a minimum price per kWh. I am not so firm about hydro, geothermal or natural gas, but I suspect that they also get some subsidies. There is a reason why a lot of the energy generation is originally state owned, because it used to be a business that cannot make profit unless the people all have to pay more. It is in that respect similar to roads or rails. Of course privatization can take hold, with all the consequences that followed (either deteroating infrastructure, rising prices or the need for subsidies). But I am getting offtopic

[redpaintednavi]

Once I read an article about another way to get power out of algae. The idea was a relatively closed system where you grew algae in a sort of tank or bioreactor (which got its energy from the sun). The alage was then dried, burned and used to heat water that powered a generator. The heat from the burn also dried new algae. The CO2 from the process was fed back into the tank to give material for more algae. Perhaps though some nutrients must be added to grow the algae.

[auroraglacialis]

If you grow them in a closed loop tank and get them out by filtration, maybe add the processed residue back to the water as nutrients, it may be possible. Up to now, such plans are a lot more expensive than open ponds though and there is an issue with algae sticking to the glass surfaces that have to exist to let light in, blocking the light for the algae in the moving water. Overall, this would still cover a lot of land, require a lot of the energy produced by it and still require water and nutrients. But mainly it is way more expensive and certainly will not be built within a few years or decades.

[Human No More]

Battery exchange and standardisation is a valid solution, but the infrastructure, both physical (battery exchange points, storage, charging facilities, distribution*) and nonphysical (billing systems, tracking of bevels of batteries in different areas and assignment of more as required, monitoring battery lifecycle). The technical issue of standardisation would probably require the use of multiple smaller batteries (for larger and smaller vehicles, both in terms of available space and power draw) but is not insurmountable. Of course, even if such a system was fully implemented today, then a battery small enough to be interchangeable without removing a significant amount of the internal structure to access it would only be enough for 10-20 miles.

* Exchange load would not be equal between areas, and unless stocks were huge and there was an extensive system to move them around, areas would face over-or under-supply of batteries as people move around.

Having interchangeable batteries would, in a very best case situation, require twice as many, and in a more realistic scenario, it could be 10 times as many or more (due to distribution differences).

As for electricity demand itself - yes, it will require a much larger production capability (and wind/solar will not be able to fill it due to the peaks and dead times they create - over here and in many other countries, windfarm operators actually sell their produced energy below cost due to the nature of baseload systems meaning that there is often very little demand for it when it is available thanks to its intermittent nature, and they make their actual profit from subsidies and not energy - it would be perfectly possible for them to remain profitable while simply running the electricity to an earth instead of the national grid if the subsidy was still be available in that context), but the efficiency percentage is much higher, resulting in less total energy produced for the same amount by in the end consumer - even if all vehicles were electric and all the electricity was produced by oil, the oil consumption would be less than them using the oil directly.

[Human No More]

True
Well, with the existence of hybrids today, it isn't implausible to have a system with both.

[applejuice]

Is there any solid indication that algal fuels are going to be better than oil? If we are going to dedicate enormous extensions of land to produce fuel, then the product has to be, at least, as cheap as the oil-derived fuel.