Green Building Forum - A bit of sense on biofuel at last

A bit of sense on biofuel at last

SteamyTea — Wed, 17 Oct 2012 21:38:40 +0100

Seems that some scientists are getting the message though at last.
http://www.bbc.co.uk/news/world-europe-19982214

A bit of sense on biofuel at last

fostertom — Wed, 17 Oct 2012 23:23:13 +0100

http://www.avaaz.org/en/eu_feed_kids_not_cars_b/?brfaebb&v=18743

A bit of sense on biofuel at last

Seret — Thu, 18 Oct 2012 07:21:18 +0100

Er, "some scientists" have been saying this all along. Bottom line for Europe though is that like North America there's an agricultural surplus, so using it for energy crops makes some sense. People have always said that displacing food crops or clearing land is much less useful. In other words: this is not news.

A bit of sense on biofuel at last

SteamyTea — Thu, 18 Oct 2012 09:33:58 +0100

Posted By: SeretIn other words: this is not news.

Too true.
The problem is really global wealth distribution and not realising just how well off we are in the developed world.

A bit of sense on biofuel at last

fostertom — Thu, 18 Oct 2012 10:08:15 +0100

AFAIK, road fuel from bio sources has EROEI (Energy return on energy invested) of less than 1 i.e. on a full accounting, more energy is invested into growing crops, harvesting, processing, distributing the 'fuel', than the fuel contains (let alone how much of that content gets usefully used - about 30% for road fuel). So it's going backwards, energy-wise. At best, it's converting basic crude energy 'sources' into a special-purpose hi-grade form of same, albeit v wastefully.

A bit of sense on biofuel at last

djh — Thu, 18 Oct 2012 12:59:10 +0100

Posted By: Seretthis is not news

Yes it is. The news is that the EU has acted and is going to change the law. Yay!

A bit of sense on biofuel at last

Seret — Thu, 18 Oct 2012 18:33:55 +0100

Correct me if I'm wrong, but 5% biofuel was the target before anyway. So nothing had changed AFAICT.

Tom, petrol and diesel are the same. Getting energy into a convenient, dense, portable form is generally quite wasteful.

A bit of sense on biofuel at last

fostertom — Thu, 18 Oct 2012 19:05:00 +0100

Posted By: Seretpetrol and diesel are the same

Really? Meaning that it takes more energy to extract, than it contains?

I knew oil in general was into ever-decreasing EROEI, but still well over unity AFAIK.

In the refinery, it's not just petrol/diesel that's being produced, but a raft of other useful distillates which share the 'cost' of the energy input to production - can't lump it all onto the petrol/diesel.

A bit of sense on biofuel at last

Seret — Thu, 18 Oct 2012 22:14:02 +0100

Depends how you do your sums Tom. If you're as pessimistic about oil as you have to be about biofuels to get eroei below 1 then oil doesn't look good. Like all these things you've got a range of numbers to choose from, and the end result is usually chosen to support the author's agenda. Certainly there are both good and bad sources of oil and biofuel. Pick whichever supports your position best! Few sources of biofuel come really close to eroei = 1, but some sources of oil (e.g. Tar sands) are really bad too. Beware of data about US biofuels in particular, they're growing the wrong stuff for the wrong reasons, so aren't ever likely to get good numbers.

A bit of sense on biofuel at last

wookey — Fri, 19 Oct 2012 04:11:41 +0100

Seret - the target was due to rise to 8% or 10%. I think the news is that that rise has been cancelled. I was ambivalent about the Avaaz 'kids not cars' campaign. Neither are good in sustainability terms; I don't want more kids _or_ cars using up resources. The idea that more people is a good thing has got to go.

A bit of sense on biofuel at last

Ed Davies — Fri, 19 Oct 2012 14:03:52 +0100

Posted By: SteamyTeaSeems that some scientists are getting the message though...

Posted By: SeretEr, "some scientists" have been saying this all along.

Saying is not the same as getting the message through. Half the messaging job belongs to the listener.

A bit of sense on biofuel at last

djh — Fri, 19 Oct 2012 14:04:06 +0100

Posted By: SeretCorrect me if I'm wrong, but 5% biofuel was the target before anyway. So nothing had changed AFAICT.

I'm no expert, so I'd be very interested to see the existing target that you're quoting. I don't think it exists, because the proposed legislation suggests that the new limit will be set to the current production level (note, actual, rather than permitted). But even if the limit does already exist there has still been change, including the 60% threshold. The actual proposal is 23 pages, so it's an absolute masterpiece if it makes no change at all!

http://ec.europa.eu/clima/policies/transport/fuel/docs/com_2012_595_en.pdf

A bit of sense on biofuel at last

chriskemp — Tue, 23 Oct 2012 20:14:35 +0100

Although synthetic fuels from waste plastics and/or waste tyres does make sense, and is something I am personally involved with.

Even at the most sophisticated recycling facilities, thousands of tonnes of plastics end up as landfill as they cannot be segregated/identified and therefore cant be recycled.

These can now be "reverese engineered" into a diesel-oil to power generators or via further refining and mixing be used in HGVs/farm plant.

A bit of sense on biofuel at last

fostertom — Tue, 23 Oct 2012 21:15:36 +0100

Might be better to allow plastics to be stockpiled in landfill, rather than burnt, as petro-feedstock becomes scarce and/or pricey and/or unreliable supply and/or prioritised for 'essential (aka military/police) uses - then to be quarried as precious commodity. Very clever automatic sorting technology exists, thanks to Australian mining spinoff, just not economic for thoroughgoing recycling yet. Burning stuff is nowadays bad by any measure or standard.

A bit of sense on biofuel at last

chriskemp — Tue, 23 Oct 2012 21:35:44 +0100

The process i am involved with is non pyrolisis based / not incineration.
We are looking to 'dilute' / co mix the synthstic diesel oil with normal diesel for council vehicles.

A bit of sense on biofuel at last

fostertom — Wed, 24 Oct 2012 09:38:48 +0100

That sounds good, but in the end the product gets burnt (finite-resource hydrocarbon chains oxidised to exothermic smithereens), which is a poor way to create energy, that robs our nest-egg of intact-hydrocarbon feedstock.

A bit of sense on biofuel at last

chriskemp — Wed, 24 Oct 2012 16:03:46 +0100

But surly better than virgin diesel. And better than festering in landfill, requiring more virgin diesel and so on and so forth.
Shall be along time till hgvs and dump trucks run off something else.....

A bit of sense on biofuel at last

SteamyTea — Wed, 24 Oct 2012 17:34:57 +0100

Posted By: chriskempShall be along time till hgvs and dump trucks run off something else.....

They could run of bio-gas or current batteries (assuming running time is known in advance). Neither is my favourite technology though.

A bit of sense on biofuel at last

fostertom — Wed, 24 Oct 2012 18:23:29 +0100

Posted By: chriskempbetter than festering in landfill, requiring more virgin diesel

Would plastics 'fester' or remain intact? Why would being stockpiled in landfill require ongoing diesel?

A bit of sense on biofuel at last

chriskemp — Wed, 24 Oct 2012 18:37:58 +0100

I mean on going diesel requirement for an existing councils fleet of vehicles.
Where said council has access to thousands of tonnes of plastics which currently go to landfill....

So they are currently paying to landfill and paying to fill their tanks with diesel.
Both costs are increasing.
Not sure where the cash would come from to upgrade to electric buses, vans, garbage trucks etc.

Forgot to mention the council are looking to increase the plastics they take in. By this i mean the plastics with commercial resale are limited and there are many items currently turned away.
Thereby increasing their gate fees too.

A bit of sense on biofuel at last

chriskemp — Wed, 24 Oct 2012 18:41:40 +0100

They could run of bio-gas or current batteries (assuming running time is known in advance). Neither is my favourite technology though.

Both of which shall require a larger investment.
You can of course have dual fuel using biogas and the sythetic diesel from the waste plastics.

My point is that the oil has been drilled to make the plastics already. I can turn said waste plastics into a synthetic diesel, reducing the requirement, and i mean millions of litres less "virgin" diesel to be drilled and refined etc.

A bit of sense on biofuel at last

Seret — Wed, 24 Oct 2012 18:54:55 +0100

Posted By: chriskemp
Not sure where the cash would come from to upgrade to electric buses, vans, garbage trucks etc.

They'll need to be replaced at some point. Electric buses have been common for donkey's years in some parts of the world, they're not exotic technology. The fact they run on defined routes makes electrifying them easy, no batteries required.

However, turning any kind of waste into something useful is a great idea. We should be doing as much as possible.

A bit of sense on biofuel at last

chriskemp — Wed, 24 Oct 2012 18:58:25 +0100

The following cannot be recycled currently. (at this council at least, and also mine incidently)
But can be used for synthetic diesel

Margarine and yoghurt pots
Plastic cups
Plastic food packaging
Other plastic packaging
Carrier bags
Cling film

Plus of course tyres and the "fluff" from end of life vehicles

A bit of sense on biofuel at last

chriskemp — Wed, 24 Oct 2012 19:02:50 +0100

Fair point on the buses. When they come to their natural end of life I guess.
Although an electric bus is still only as green as the method the electricity was generated.....

A bit of sense on biofuel at last

SteamyTea — Thu, 25 Oct 2012 06:55:12 +0100

Really much more interested in turning my milk carton into diesel, is this the microwave process I read about a few years back and what energy is required to convert it back. Does that include transport from home to processing plant.

A bit of sense on biofuel at last

chriskemp — Thu, 25 Oct 2012 07:39:46 +0100

Plastic milk cartons are no problem.
I am looking at setting up facilities as close to vast quantities of waste as possible.
No this is not microwave tech, the polymer chains are broken under preheat, friction and pressure. To produce a liquid"diesel".

However, smaller transfer stations scattered around, grinding the waste into crumb before being transported to the refining plant also makes sense (this is what we have proposed to a large tyre fitting co).

Once the waste is a diesel it can be moved with ease to generators too, even if just back up gennys.

A bit of sense on biofuel at last

SteamyTea — Thu, 25 Oct 2012 07:56:45 +0100

Posted By: chriskempthe polymer chains are broken under preheat, friction and pressure

Is that very energy intensive?

I used to work next door to a company that made plastic recycling machines, they used a similar process. Some plastics, polypropylene I seem to remember, were just not worth recycling because virgin feedstock was so cheap. Wish I had taken more notice of the power requirements of their machines at the time. I know that our lazer cutters/engravers, that made waste for them somedays, were pretty inefficient and a simple 3D CNC router would have been better for most jobs.

A bit of sense on biofuel at last

chriskemp — Thu, 25 Oct 2012 08:46:37 +0100

still working on the real details as I am kept at arms length in a way, I'm just making the intro's at the moment.

runs at 330deg C I found out yesterday.
circa 19,000 MWHr (NET) output depending on feedstock per year, via a circa 2.5MW genny.

A bit of sense on biofuel at last

SteamyTea — Thu, 25 Oct 2012 09:11:56 +0100

If the 2.5 MW generator is running 24/7 then that is 21,900 MWh
If it runs for 8 hours a day, 5 days a week, then it is 5,200 MWh, may get that out of a 5 kW PV system for an investment of less than Â£8000.
Not poo-pooing the idea, actually like the idea of turning plastic waste into a fuel as I like to go places easily and cheaply.

A bit of sense on biofuel at last

chriskemp — Thu, 25 Oct 2012 09:46:47 +0100

yes refining the fuel appeals to me more too.
*those figures include downtime for maintenance, and vary on feedstock.

The ROCs, and reduced landfill taxes, and gate fees for feedstock makes this more far appealing to a Local Authority / ESCO than PV ;-)