Jump to content



Featured Articles

Check out the latest featured articles.

File Library

Check out the latest downloads available in the File Library.

New Article

Product Viscosity vs. Shear

Featured File

Vertical Tank Selection

New Blog Entry

Low Flow in Pipes- posted in Ankur's blog

A Waste Of Time?


This topic has been archived. This means that you cannot reply to this topic.
6 replies to this topic
Share this topic:
| More

#1 StealthProg

StealthProg

    Gold Member

  • Members
  • 51 posts

Posted 05 January 2010 - 06:11 AM

I really struggle to understand what the point of biofuels is, maybe somebody can put forward a convincing argument to make me a believer.

Growing biomass is an incredibly inefficient way to harness energy, animal products are even less efficient. The human population is set to reach 9 billion in the next 50 years and the amount of farming land needed to make even a small dent in crude oil consumption would be huge. There is not enough agricultural land on the planet to replace the current level of oil consumption with biofuels, even if people stopped eating.

With the exception of truly waste materials which is ok, really what is the argument for Biofuels?

#2 riven

riven

    Gold Member

  • ChE Plus Subscriber
  • 178 posts

Posted 05 January 2010 - 08:02 AM

The arguement for corn based or other food based fuels is definately debunked; too much land will be required and this will reduce food stock.

However the other options may be viable. 2nd generation ethanol can be based on the non edible parts or plants that can be grown in land not particularly useful for farming. Another option in algae could use the vaste dead zone areas of ocean.
Also remember than ethanol is only a first generation fuel; potentially more efficient fuels like 'bio'butanol are being developed and this could help.

But this kind of avoids the real problem. Currently, food production (no including biofuel) in the world amounts to a land area the size of Sounth America. To cope with the increased population an area the size of Brazil would need to be added to food production lands. Also when we consider the high water stress that many countries already exhibit and that ~70% of water usage goes into agriculture using existing technology, I do not think this expansion is possible or feasible (then consider fertilizer use).

Hydroponics aeroponics etc have been proven and need to be scaled up to reduce water and soil usage. Verticle farming could also be a possibility especially if we develop 24h & 365days growth (or close).

The reason for using biofuel is clear; existing strategies can be adapted relatively easily for the current transport fleet.

Consider if we switch to an electicity based transport fleet. Aside from building massive amounts of thorium reactors or 4th generation nuclear plants (not due until 2050 at least; forget fusion aside from miracle breakthrough) we have to rely on solar and wind etc (Wave will not feature significantly nor will tidal). These systems also require large areas and they face the same problem in that they must be located in poor agricultural areas/deserts. Further these sources of power are intermittant as oppsoed to biofuel which would be continuous based on supply in the same way that oil is. So power storage both large (hydo-resevoirs) and small (batteries) will be needed.

Current predictions for these technologies is that these will be a shortage of lithium (batteries) and rare earth metals (for fuel cells; turbines) if we were to apply these technologies to the full fleet.

Ultimately no one stop solution will be available and while I would love to see a total electic economy (both power supply and fuel) because of its potential simplicity and efficienty I do not think it is possible. Noone really knows what the best mix will be.

Consider that oil cannot do everything; gas and nuclear are required. A mix is needed.

#3 StealthProg

StealthProg

    Gold Member

  • Members
  • 51 posts

Posted 05 January 2010 - 01:04 PM

I agree nuclear is a realistic option for long term energy production.

Oil and Natural Gas are likely to start reducing in production relatively soon (some would argue it has already, but thats a moot point). I don't see any way in which biomass can replace even a fraction of oil production.

Significant biomass energy production just seems to be a fantasy and a distraction from the real issues (and so far has had the side effect of helping to destroy large areas of tropical rain forest).

#4 djack77494

djack77494

    Gold Member

  • ChE Plus Subscriber
  • 1,282 posts

Posted 06 January 2010 - 05:24 PM

Biofuels are not the answer, but they could be a part of the answer. The problem is so big that many pieces will be required to construct our solution. I think the biggest pieces need to be population control and nuclear energy.

Population control is already occuring in much of the developed world where people average less than two children per family (if immigration is not counted). We need it to get less developed countries and peoples on board, but there are many cultural and religious obstacles to this. Nuclear energy is an available option right now. Longer term, we should be doing lots of R&D towards fusion-based nuclear energy. Any longer term solution will need to be highly innovative. Biofuels = energy from algae and not energy from corn. Current biofuels technology such as corn based ethanol are clearly not the answer. Production consumes enormous resources including oil and gas for fertilizer and transportation for very little net benefit. But ultimately if we fail to address population control then old familiar answers will solve our problem. I'm thinking war, starvation, disease, etc. Think we're capable of better solutions? I'm not so sure.

Edited by djack77494, 06 January 2010 - 05:25 PM.


#5 StealthProg

StealthProg

    Gold Member

  • Members
  • 51 posts

Posted 07 January 2010 - 07:54 AM

I don't think we are capable of better solutions and I agree population control is the only viable solution long term. We simply don't need 9 billion people on the planet when in reality it can probably only support less than a billion living a 'modern' lifestyle.

#6 Zauberberg

Zauberberg

    Gold Member

  • ChE Plus Subscriber
  • 2,704 posts

Posted 28 February 2010 - 07:35 AM

This planet has sufficient resources to feed, not 9 but 99 bilion people. The problem is not in numbers, the problem is in the heads of "elite" groups - the greed that will never stop. If I recall the figures correctly, something like 90% of Earth resources is in possession of 5% of Earth population, and that is the source of problem. Like it or not - Exxon, Shell, BP, Total - these are the worst enemies of mankind.

#7 svr2112

svr2112

    Brand New Member

  • Members
  • 2 posts

Posted 19 August 2010 - 05:41 AM

It takes a lot of diesel to seed the fields, irrigate the land, spray the insecticide/herbicides, harvest the rapeseed, transport them to a facility, squeeze out the oil, transestify them into bio-diesel and deliver them to market so who knows how many gallons of diesel you're burning with each gallon of biodiesel. Besides, you can't grow enough of anything to provide for our current energy demands so biomass can only be part of the answer not all of it.

Bio-diesel will play a part in our future, mostly as an additive to dilute high sulfur diesel to meet low sulfur requirements, and as a lubricant to synthetic diesel since synthetic diesel has no sulfur to lubricate the engines with. It's major use will be as a marketing tool to make people believe they are environmentally friendly.

___________

Life Cover | Life Insurance




Similar Topics