Is bio diesel as good as we think?

milanonaj

I have recently been told by a business owner who was using bio diesel that studies have shown it not to be the clean fuel that we all thought it was.

I run vehicles in the course of my business and was considering switching to bio diesel before being told this. What is the truth?

AngryPig

I think the jury is still out on this one, and it also depends on the source of the biodiesel. The majority is made from used cooking oil from various sources (chip shops, restaurants, canteens, food industry...). It can also be made from virgin oil crops, which leads to a much bigger ethical debate (food vs fuel & deforestation to make way for palm oil plantations).



There is a clear environmental benefit to converting old cooking oil to make a fuel, but there are a number of downsides to it, including:

• The methanol used in its production usually comes from a fossil fuel source (natural gas).
• The production process results in a significant quantity of waste by-product (glycerol), which has limited applications and is often transported oversees for incineration.
• Production also requires an input of heat energy (often some product biodiesel is used to provide this) and other chemicals, all of which further increase the environmental footprint of the fuel.
• The logistics of cooking oil collection and fuel distribution also reduce the net environmental benefit.

All-in-all its resolves the problem of what to do with waste cooking oil and reduces our reliance on traditional diesel, which must be no bad thing, but it does consume some of the energy it provides (although I believe if done properly, the processs is a net producer of useful fuel).

If the biodiesel industry can source non-fossil fuel methanol (eg from a biogas source) and develop a market for the surplus glycerol it would be an all-round winner. some work still to be done methinks!

There are also claims that biodiesel burns "cleaner" in an engine as it does not contain the same contaminants as mineral diesel, and therefore achieves a better fuel economy - this would make sense, but I have no idea whether there is any validity to it - does anyone have any experience of improved fuel economy with biodiesel?

milanonaj

AngryPig wrote: »

I think the jury is still out on this one, and it also depends on the source of the biodiesel. The majority is made from used cooking oil from various sources (chip shops, restaurants, canteens, food industry...). It can also be made from virgin oil crops, which leads to a much bigger ethical debate (food vs fuel & deforestation to make way for palm oil plantations).



There is a clear environmental benefit to converting old cooking oil to make a fuel, but there are a number of downsides to it, including:

• The methanol used in its production usually comes from a fossil fuel source (natural gas).
• The production process results in a significant quantity of waste by-product (glycerol), which has limited applications and is often transported oversees for incineration.
• Production also requires an input of heat energy (often some product biodiesel is used to provide this) and other chemicals, all of which further increase the environmental footprint of the fuel.
• The logistics of cooking oil collection and fuel distribution also reduce the net environmental benefit.

All-in-all its resolves the problem of what to do with waste cooking oil and reduces our reliance on traditional diesel, which must be no bad thing, but it does consume some of the energy it provides (although I believe if done properly, the processs is a net producer of useful fuel).

If the biodiesel industry can source non-fossil fuel methanol (eg from a biogas source) and develop a market for the surplus glycerol it would be an all-round winner. some work still to be done methinks!

There are also claims that biodiesel burns "cleaner" in an engine as it does not contain the same contaminants as mineral diesel, and therefore achieves a better fuel economy - this would make sense, but I have no idea whether there is any validity to it - does anyone have any experience of improved fuel economy with biodiesel?

Thanks for this great answer! Now, do you think that the biodiesel, made from crops, will be the cause of increasing food prices?

Ben84

AngryPig wrote: »

I think the jury is still out on this one, and it also depends on the source of the biodiesel. The majority is made from used cooking oil from various sources (chip shops, restaurants, canteens, food industry...). It can also be made from virgin oil crops, which leads to a much bigger ethical debate (food vs fuel & deforestation to make way for palm oil plantations).



There is a clear environmental benefit to converting old cooking oil to make a fuel, but there are a number of downsides to it, including:

• The methanol used in its production usually comes from a fossil fuel source (natural gas).
• The production process results in a significant quantity of waste by-product (glycerol), which has limited applications and is often transported oversees for incineration.
• Production also requires an input of heat energy (often some product biodiesel is used to provide this) and other chemicals, all of which further increase the environmental footprint of the fuel.
• The logistics of cooking oil collection and fuel distribution also reduce the net environmental benefit.

All-in-all its resolves the problem of what to do with waste cooking oil and reduces our reliance on traditional diesel, which must be no bad thing, but it does consume some of the energy it provides (although I believe if done properly, the processs is a net producer of useful fuel).

If the biodiesel industry can source non-fossil fuel methanol (eg from a biogas source) and develop a market for the surplus glycerol it would be an all-round winner. some work still to be done methinks!

There are also claims that biodiesel burns "cleaner" in an engine as it does not contain the same contaminants as mineral diesel, and therefore achieves a better fuel economy - this would make sense, but I have no idea whether there is any validity to it - does anyone have any experience of improved fuel economy with biodiesel?

Very good answer. It's also notable that biodiesel burning emits some air pollution - but I do not believe it's any better or worse than normal diesel.

Where old cooking oil is used it seems a reasonable reuse of resources, but is it the best use of the oil needs to be considered? We could also burn it without turning it in to biodiesel, for example in a special boiler to produce hot water or in a power plant. It can also be digested to produce biogas which can be pumped in to the mains gas network - which may make more sense as the oil could then be disposed of with general catering waste which can be digested in the same way. Large catering organisations can justify the collections as they produce a lot of waste.

Oil from households is another matter. I'm sure that all the used cooking oil in the UK from households adds up to a large amount of potential energy, but like many people I put mine back in the bottle and throw it out. The trouble is that gathering it all up and doing something useful with it consumes resources and it has to pay off if it's going to be worth doing.

So, with two very different sources that have their own collection logistics, any proposals about the environmental benefits of collecting and reprocessing used oil need to be clear on the source and how it pays off.

As for growing crops to make biodiesel, that's a whole new situation with its own potential problems. We have already converted a lot of land to crops growing, so I'm not convinced that converting more is a good thing. I might be reassured by evidence of high fuel yields and that low grade land not suitable for conventional farming and with low existing biodiversity would be used - but that makes me hard to please and is possibly unrealistic.

malch

More important than the ethical side is that you might find the ethenal mixed into it could damage your engine. old engines seem to cope quite well with it, newer ones not so well.
i know a firm which switched a fleet of trucks to Bio, everything fine for a short while then a whole host of breakdowns. the fuel filters where disintergrating and getting lodged around the fuel lines. repaired only after major strip downs and a huge amount of money. None of the trucks ever ran aswell as before. it also gummed up the nightheaters.

forgotmyname

1st thing to consider before all the enviromental issues is are teh vehicles capable of running on it
without modification?

Fuel lines, Filters and pumps. Surprising what nasty chemicals are in bio diesel compared to standard diesel.

Enviromentally friendly? Probably not overall unless your using waste products to create it.

rogerblack

Note how well the cheapest oil you can buy in the shops tracks the diesel price.

Hungerdunger

ClassA wrote: »

Lets face it more land will be lost because of growing fossil fuels than would have been lost because of sea level rises.

You need to get your terminology right: the fuel that we grow are biofuels; the ones we get out of the ground (Coal and oil) are fossil fuels.

ClassA wrote: »

Also there has been no seal level rise when we burnt the first half of the fossil fuel, so the second half which will have a logarithmically smaller effect won't make a difference.

You are wrong on this. Global average sea level rose at an average rate of around 1.8 mm per year over 1961 to 2003 and at an average rate of about 3.1 mm per year from 1993 to 2003. Scientists who study this are in general agreement that sea levels will continue to rise over many years to come (even if they don't agree on the rate of the rise).

partist

ClassA wrote: »

If you think starving to death the poorest people in the world is 'green' I think you need a rethink.

Not much point in saving the planet when you are killing the people through hunger.

Very true. Though if half the world's population did die of starvation the world would be a much greener place - only half as many people generating Co2.

I've read you would need to devote the whole land area of the UK (and then some) to growing fuel crops to run all UK cars on UK bio fuel. Not very practical.

Bio fuel can be green while it remains a small, fringe activty, eg burning chip oil that would otherwise be thrown away.

Ben84

ClassA wrote: »

If you think starving to death the poorest people in the world is 'green' I think you need a rethink.

Not much point in saving the planet when you are killing the people through hunger.

Also there is scant evidence it is green. Bio fuels require fertiliser to grown and that fertiliser is fossil fuel based.


Thus you are going:
oil - fertiliser - plants - reprocessing - oil - car


AS opposed to the old:-

oil - car.


Adding 3 extra stages seems stupid.


Lets face it more land will be lost because of growing fossil fuels than would have been lost because of sea level rises.

Also there has been no seal level rise when we burnt the first half of the fossil fuel, so the second half which will have a logarithmically smaller effect won't make a difference.

I'd agree that most biofuels start with fossil fuel input when manufacturing plant food, but then the plants being grown turn energy from sunlight in to hydrocarbons that can be used as fuel, so it can be mathematically shown that the original energy input is being multiplied. When there is an increase in the energy available it's not illogical.

Biofuels can also be made from waste food sources, like used cooking oil or from plants grown in contaminated areas where food crops would not be suitable for eating. There are also the parts of plants which we don't eat which may be used too, such as coconut shells or corn stalks. There is also GM, which although controversial does have the potential to yield lots of interesting new products including fuels.

There are issues too with land use, water use and food prices. I don't immediately think biofuels are good, but then I don't immediately think they're bad because there are good examples of them working well. It's a case of it depends and we need to consider the situation.