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Keith Oakley - n/a
8-Feb-07, 08:13 AM
A BBC News item yesterday on a hydrogen fuel cell powered motorbike http://news.bbc.co.uk/1/hi/world/europe/4353853.stm (news.bbc.co.uk/1/hi/world/europe/4353853.stm) set me thinking - whats the best way to achieve a Carbon Neutral Hovercraft in say 10 years time?



Researching the hydrogen fuel cell quickly ruled that out - the motorbike cell has an output of 1kw (1.3bhp) so nowhere near powerful enough. There is a 10kw (13bhp) big brother that might (just) power a small cruiser but the cell alone weighs in at 70kg. http://www.intelligent-energy.com/images/uploads/10kw_system (www.intelligent-energy.com/images/uploads/10kw_system_a4.pdf) _a4.pdf Plus Hydrogen fuel cells are effectively batteries, they run off hydrogen which is generated in another power plant, be it oil, gas, hydro, wind, nuclear or whatever.

I seem to remember Nigel Beale researching Hydrogen car engines as part of his day job at Cranfield in the 70's. It was based on modifying conventional engines but that still has the 'hydrogen supply' problem.



Bio ethanol seems to offer a good way forward. It’s a primary fuel produced from plants like corn, wheat, grass, wood chips etc rather than a 'battery' and can be used by conventional IC engines. http://en.wikipedia.org/wiki/Ethanol_fuel (en.wikipedia.org/wiki/Ethanol_fuel) The Model T Ford of 1908 was designed to run on either ethanol or petrol. In fact it looks as if the engines we use today could be run on a 10% ethanol, 90% conventional petrol blend (so called E10) right away without mods http://www.drivingethanol.org/userdocs/SmallEnginesFactSheet (www.drivingethanol.org/userdocs/SmallEnginesFactSheet.pdf) .pdf



The EU is proposing a 20% reduction in carbon dioxide emissions from cars in 5 years. Morally we ought to try to match this particularly if it also brings performance improvements to our craft. E10 improves the burn of the engine reducing both knock and Greenhouse Gas Emissions -. eg Carbon Monoxide reduced by 30% http://www.drivingethanol.org/userdocs/EthanolandtheEnvironm (www.drivingethanol.org/userdocs/EthanolandtheEnvironment.pdf) ent.pdf



Maybe over the years we can evolve to an 85% Ethanol blend (E85). Before the 'petrolheads' start complaining raw ethanol is high octane stuff and Indy Cars in the 2007 season will use E100 - (100% Bio Ethanol http://www.drivingethanol.org/userdocs/EthanolEnginePerforma (www.drivingethanol.org/userdocs/EthanolEnginePerformance.pdf) nce.pdf ). Pure ethanol has a much higher octane rating (116 AKI, 129 RON) than ordinary gasoline (86/87 AKI, 91/92 RON), allowing a higher compression ratio and different spark timing for improved performance. To change a pure-petrol-fueled car into a pure-ethanol-fueled car, larger carburetor jets (about 30-40% larger by area), or fuel injectors are needed. (Methanol requires an even larger increase in area, to roughly 50% larger. The production process for Methanol is apparently not very green)



The only downside seems to be that Ethanol contains approx 34% less energy per gallon than petrol so a craft running on say E85 will need a larger fuel tank. Earlier craft running on E10 would see little consumption difference (around 3%)



The problem is that in the UK only a handful of Tesco and Morrison Garages currently stock it and production capacity is limited. Perhaps in the classic hovercraft diy spirit Charlie and Jake should grow a bio fuel in the centre of our two 'home' racecourses, produce it themselves then sell it for diy blending at race meetings. I presume as it's not for a road vehicle it would attract no tax….! Apparently an acre of Miscanthus (elephant grass - http://en.wikipedia.org/wiki/Miscanthus (en.wikipedia.org/wiki/Miscanthus) ) can produce 1500 US gallons, about enough for 2 Nationals with every craft using using E100. One UK manufacturer in Gloucestershire is about to sell a small (legal) production plant for farmers to produce Bio Ethanol http://www.greenfuels.co.uk/index.htm (www.greenfuels.co.uk/index.htm)



Even the UK Government thinks it’s a good idea - http://www.defra.gov.uk/farm/crops/industrial/energy/pdf/Bio (www.defra.gov.uk/farm/crops/industrial/energy/pdf/Biofuels-leaflet.pdf) fuels-leaflet.pdf

But not everyone agrees, York Uni http://www-users.york.ac.uk/~drf1/bf/html/bioethanol.html (www-users.york.ac.uk/~drf1/bf/html/bioethanol.html) points out that for every 133 units of energy produced 100 units is used in the production process. However University College London points out that with the right production plant design Bio Ethanol could actually net extract CO2 from the atmosphere. http://www.britishsugar.co.uk/IsolatedStorage/94175874-67b5- (www.britishsugar.co.uk/IsolatedStorage/94175874-67b5-4c33-9f38-380233f14049/ContentAssets/Documents/Bioethanol/Publications%20and%20Research/Imperial%20College.pdf) 4c33-9f38-380233f14049/ContentAssets/Documents/Bioethanol/Pu blications%20and%20Research/Imperial%20College.pdf



So Bio Ethanol seems to me (with only a poor O Level in Chemistry) a viable way forward for keeping our sport going in a Carbon Neutral World. It means minimal changes to our craft and engines and overall the pros seem to outweigh the cons.



But most of us use more fuel getting to the meetings than in our craft - any ideas for a Carbon Neutral RV? Does it also mean we should encourage renewable plywood craft held together with fish glue rather than fossil fuel based fibreglass? (sorry Russ couldn't resist it!)



Fuse lit, over to you all for discussion…



Keith Oakley

Nick Long - n/a
8-Feb-07, 09:22 AM
Interesting post, Keith, as ever.



It is also interesting how, in the 30 or 40 years since it became an issue, the buzz words have moved through energy efficiency, conservation, renewables, sustainability, etc and now to carbon emissions, carbon neutrality. The latest and best is the "carbon footprint", which may not be a good scientific measure, but does conjure up images of Victorian chimneys and coal miners at the end of a shift.



In fact it all boils down to much the same thing. That is not necessarily so, of course, but with the current patterns of energy use a reduction in consumption is a better goal than a switch to a different form of consumption. That was the case in 1973 when the oil shock woke people up, and after all the progress since, it is still the case.



Unfortunately, our racing rules encourage more rather than less consumption. I wrote at length in the magazine a while back about the obsession with classifying formulas by engine size rather than any other parameter. So I am a little sad to see Comps introducing yet another formula on this basis.



I have proposed several times, and others have also, the idea of a formula where there is no engine limit but the amount of fuel used in the race is limited. This is in effect setting a limit on the carbon emissions of the craft. It would be a very good first step to reducing the carbon footprint of hovercraft racing. Instead though, we get the hugely imaginative F1X.



-------



As for construction, you contrast "renewable" plywood with the "fossil fuel" grp. In terms of carbon, they are actually similar - both methods are locking carbon up in the hull. The issues are then what is done with the craft at the end of life and how much energy was used in the production.



-----



Interesting topic, and I hope this helps.



Nick

tonybroad - n/a
8-Feb-07, 10:05 AM
We're doing some research at the university on 'green racing' and the use of bio fuels in race cars, the research is focused on both performance capabilities and emissions



the good news is once the engine has been tweaked to run the fuel the 85% BioEthanol fuels seem to perform well compared with regular petrol, but the downside is that the Bio fuels aren't as eco-friendly as some would make out, still a step in the right direction is at least a step



think we need an article in the mag about this



Tony

Derek Sweetman - n/a
8-Feb-07, 12:02 PM
Schemes for re-cycling of composite materials are being worked on see this link www.ecrc-greenlabel.org



Regards

Derek

team black - n/a
8-Feb-07, 07:16 PM
I don't know if I was half asleep this morning, but I'm sure I heard something about carrot reinforced plastic having been discovere by a Scottish uni. If the other rado 2 listener heard it, please confirm I wasn't dreaming...



Of course, it could have been parrots....

Ian Brooks - n/a
8-Feb-07, 08:00 PM
We can reduce our "carbon footprint" fairly easily in the case of most cruising craft, if we shift our focus in design from race-derived pedigree to efficiency.



As an example - we can probably achieve a 20% reduction in carbon emission (fuel consumption) by making our lift systems more efficient. Lift systems which are fixed to the thrust engine speed (integrated and shaft drive) consume around 30% of power; yet under most circumstances 10-15% of power would provide an adequate cushion, with the peak required occasionally. Thus some type of variable transmission could get us to the 20% target. As another eaxmple, we can reduce our carbon emmision by 40% by moving away from 2 strokes.



Making the point a little wider, most craft development is currently driven by racing. This ethos leads to low efficiencies and high noise levels, and by modifying the design criteria for cruising craft there are some fairly easy gains to be made. Cruising craft and racing craft should be quite different - think F1 and MPV!



Ian

jar2 - n/a
8-Feb-07, 08:19 PM
Interesting links, Keith.



I'm still not convinced on the emphasis that is placed on car emmisions. As Nick says, reducing consumption is the key. To do that would require major social and economic change - moving people closer to workplaces would be a good start. Reducing consumption would also be a good thing at race meetings (no more two strokes?).



As to hovercraft, the answer is simple (!) - maybe it's time we moved onto vegetable oil burning diesel engines. More efficient, cleaner and cheaper!



The good thing about cruising hovercraft is that we are re-cycling old car engines - thus reducing their overall carbon footprint. It is said that the emmisions produced during the manufacture of a car are greater than those generated during it's lifetime.



I'm not sure of the argument for plywood versus resin. By using resin you are producing a product that will outlive plywood by at least three times. Does the carbon emmited to produce (and dispose of) three plywood hulls equal one resin/glass hull?

jon_curtis - n/a
8-Feb-07, 08:24 PM
what if the craft has carbon fibre in it lol!

team black - n/a
8-Feb-07, 09:18 PM
Got it!!



http://news.bbc.co.uk/1/hi/scotland/edinburgh_and_east/63423 (http://news.bbc.co.uk/1/hi/scotland/edinburgh_and_east/6342381.stm) 81.stm



Just in case anyone thought I was taking the mick

hovmart - n/a
8-Feb-07, 09:53 PM
will be paying rabits to lay up craft and they get to eat the trimings

charfont - n/a
9-Feb-07, 11:40 AM
whilst looking at how much of an impact craft may be adding to the carbon foot print, what about the impact of members traveling to and from race/off shore meetings how many thousands of collective miles are there? consider if no one had a weekend hobbie and we all stayed at home and played with our battery hovercrafts? where to start? ban all motor sport? can of worms open.. http://hovercraft.org.uk/images/icons/smiley_icons/icon_cry.gif

Keith Oakley - n/a
9-Feb-07, 01:02 PM
I agree with Charlie that fuel for RVs etc is probably as big an issue as craft fuel. But it's exactly this kind of 'end of the world is nigh' view that made me look into the issue. I believe the good news is that with suitable changes to the fuel we use both for craft and RVs our sport could carry on virtually unchanged. We could continue to use todays range of engines and, for those that want to, we could travel to weekend meetings. We don't need to retreat to operating wind powered battery craft on our home lawn.



In fact finding a 'minimal impact approach' is one of two key 'tests' I had in mind when looking for a way forward. The second was that there would inevitably be areas like craft (or RV) manufacture where we couldn't be fully carbon neutral so we should take every opportunity in those areas like craft (or RV) operation where we really could be fully carbon neutral. This would mean we should over time aim for full neutrality in the fuel area not just carbon reduction.



This brings me on to Nick, Ian and John's comments. I fully agree with using low revving 4 stroke engines both because of their low noise and generally better fuel efficiency, 2 of my own 3 craft are in this category. Other efficiency improvements which lead to reduced consumption are also welcome. But to insist on over 50% of current craft switching to this type of engine fails the minimum impact test. Equally moves to improve efficiency etc are welcome as carbon footprint reducers but in the long term they fail the full carbon neutral fuel test.



With tongue in cheek I presume a craft made of wood, reinforced with carrots, glued with (what?) could at end of life be chipped and turned into more ethanol...? I guess the metalwork inc engine is recyclable (unfortunately requiring more energy hence test 2 above)



With tongue still in cheek I find it surprising how few acres would be needed to support our whole sport, craft and RVs. I wonder how far we could get on the grass cuttings we produce each year cutting the grass on all our land courses. As well as race control should we be towing an ethanol production plant around to all our meetings? - no fuel miles there!



More seriously I'd like to go into this issue more in a future mag article, but what we need is more on the issues around using ethanol - impact on engine performance, reliability, availability, practicality etc -any contributions?

Russ Pullen - n/a
9-Feb-07, 05:31 PM
whilst looking at how much of an impact craft may be adding to the carbon foot print, what about the impact of members traveling to and from race/off shore meetings how many thousands of collective miles are there? consider if no one had a weekend hobbie and we all stayed at home and played with our battery hovercrafts? where to start? ban all motor sport? can of worms open.. http://hovercraft.org.uk/images/icons/smiley_icons/icon_cry.gif








Completely agree Charlie.



Not entirely sure that a few smoky two strokes buzzing around a field for a few weekends in summer is going to destroy the ozone layer (or whatever this hippy, tree hugging, hippy mumbo-jumbo is all about)



I read a few years ago, that the fuel used by a formula one GP team during an entire seasons racing and testing amounted to less than that used by a 747 to fly the team to Brazil.



Which kind of keeps it all in perspective.



Or to look at it in another way, my 35bhp cruiser uses, typically (not at the worlds... http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif) 6-7 litres an hour cruising in a coastal environment, averaging around 25mph. Or, around 30-40% less than an equivalent size 35hp boat at the same speed.



Noise is the enemy and biggest threat to our sport, sod the carbon, we're not being challenged or questioned about it and I can sleep soundly at night knowing my hover has a negligible effect on the environment at all.



We should be responsible in our use of our toys, for sure, but in my opinon, chasing carbon neutral hovers is just a nonsense.



YMMV of course.



Russ

Derek Sweetman - n/a
10-Feb-07, 07:17 PM
And to go together with the plant fibres, how about resins made from vegetable oil!

http://www.bc.bangor.ac.uk/about-us/case-studies/case-study- (http://www.bc.bangor.ac.uk/about-us/case-studies/case-study-1/) 1/



And just for Euan a link to some more fibres and to research in Bangor Wales!

http://www.flaxandhemp.bangor.ac.uk/



Regards

Derek

keith_b - n/a
12-Feb-07, 09:01 PM
As far as transport, it is possible to run a Diesel car/van carbon neutrally now.



I have converted my car, an E39 BMW 5 series, to run on 100% vegetable oil. I fill it up from a tank of veg oil sitting in my garage. The oil costs me 92p/L (78p/L on 2008) with all the Govt duties paid, the car runs exactly the same on veg oil as regular Derv, even at -5 degrees (Diesel is the name of the inventor of the engine, Derv is the fuel we buy from garages). The oil I use is mechanically produced from rape seed grown in Kent (there is some use for this county afterall). I can mix Derv, "biodiesel" (think of this as low tar cigarettes) and any veg oil (Rape seed, olive oil or whatever). The car smells pleasantly of chips when it is running.



Overall it costs more than regular Derv. I have done this because I am an angry customer and an affronted "engineer", Rudolf Diesel designed the engine over 100 years ago to run on organic oil, not mineral oil. We have all been brought up with the knowledge that we must only use mineral oil sold by the oil companies, even though it was ruining our environment. Any challenge to this has been met with disbelief and stories of doom by pretty much everyone, which is a shame. I consider that this is as bad as way the tobacco companies operated in the fifties.



These are the guys who did the work on my car, www.bloomingfutures.com, John is a an aeronautical engineer and did a cracking job.



Unfortunately I use my elderly VW van to get to meetings but this will hopefully be of use to some.



Just waiting for a lightweight Diesel for the craft, if anyone knows of one I am more than happy to progress this technology.



Keith Burchfield

hovmart - n/a
13-Feb-07, 01:39 AM
they have a diesel microlight in the usa, based on the smart car diesel engine, if it will work for them it would work in a craft

try there web site http://www.ramphosusa.com/TurboDpage1.html

kach22i - n/a
14-Feb-07, 03:16 PM
I've been reading about adding 20 to 30 percent water into a Diesel fuel mix to lower emmisions and improve performance. It might even work with bio-diesel. The state of California has supported such efforts but I'm not sure where it stands today.



EDIT:

I've been told that water and Diesel fuel don't play well together, water tends to blow out and destroy the rail injector tips.

Russ Pullen - n/a
15-Feb-07, 10:36 AM
rape seed grown in Kent (there is some use for this county afterall).








Says the man who lives in the UK's Gay/Drug Capital..... http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif



Keith - thats mad! You're paying MORE for the fuel in your car than you can buy it at the pumps.... out of principle?



You'd think that being grown 50 miles away would make it cheaper than Iraqi oil, but i guess by the time Brown and his crooks have slapped a selection of taxes all over it, the actual material cost is largely irrelevant.



Quite happy to use bio in my diesel Beemer, but no way will i pay more for it.

keith_b - n/a
16-Feb-07, 06:31 PM
Russ,



It costs me about 5 month extra at the moment for the Veg fuel from Kent as it is about 3p more than Derv this week and I do about 15,000 miles a year.



I think the 5 a month is worth paying for the principle though, I am that annoyed, mad, fed up about the whole thing. Everytime I fill up in a petrol station I feel like I am being mugged. We are going to be slaughtered for tax in the next few years to reduce our carbon output from cars when we don't have to produce the carbon in the first place and therefore not pay any environmental tax! I'd much rather pay a Kent farmer the money than some company that keeps its money anywhere but the UK, which includes avoiding tax which we can't.



Next year Veg will drop 15p/L when a tax break kicks in. The payback is three years with a 15p difference to Derv, Derv is likely to go up over the next year or so anyway.



In Brighton, 5 is 1.5 pints only these days anyway. I don't know how much the drugs or gay men cost, I'll ask around if you want http://hovercraft.org.uk/images/icons/smiley_icons/icon_biggrin.gif .



Keith

Keith Oakley - n/a
26-Feb-07, 10:48 AM
Growing our own fuel - sounds like the Top Gear team have got there first to judge by last night. I doubt we need the 250k tractors though.

Jamie Lewendon - n/a
26-Feb-07, 11:46 AM
I think John speedthing has the seed spreading sorted out. He made an attachment for granvilles craft that spread grass seed, for use on a scottish peat bog. Not sure how succesful it was though. All we need now are a hover plough, and a hover cultivator. If TG is anything to go by. Oh and some explosives.



Jamie

chrismdaly - n/a
27-Feb-07, 06:39 AM
Utilising hovercraft in Agriculture was in its experimental stage in the 70's. The main draw back in using them for spraying or seed distribution was the air turbulence close to the machine. The bonus that everyone wanted was to apply sprays or seed when the ground conditions would not carry a wheeled vehicule. In other words the hovercraft was the best low ground pressure vehicule. The major problem with wheeled vehicules in wet conditions was the long term damage to the soil structure which gave a corresponding long term drop in crop yield.

keith_b - n/a
2-Aug-07, 10:47 AM
A follow up on veg oil in cars, I got the dates wrong on cheaper fuel - this briefing from HMRC mean tax free veg oil for personal use (<2501 litres oil per year)- I have checked with HMRC - no VAT and no fuel duty.



http://www.hmrc.gov.uk/briefs/excise-duty/brief4307.htm (www.hmrc.gov.uk/briefs/excise-duty/brief4307.htm)



65p/Litre in tescos to run my car... probably cheaper elsewhere



56p/Litre in Asda.

jon_curtis - n/a
2-Aug-07, 05:01 PM
it does not say you can use veg oil, in your car with no duty! it classes this as a blend or substitute and is subject to duty!



verg oil is a hydrocarbon.

keith rhodes - n/a
2-Aug-07, 05:02 PM
how about composting and capture the methane. a mini airship full on top of the hover craft will remove the need for a lift engine http://hovercraft.org.uk/images/icons/smiley_icons/icon_lol.gif

keith_b - n/a
3-Aug-07, 08:34 AM
Dangerman,



Fresh Veg Oil is classed as a Bio Fuel by the treasury but not the DoT (!) but you are not wrong in what you read in the HMRC doc about veg oil - so I phoned HMRC yesterday and asked directly about buying fresh cooking oil from Tesco/Asda to use in my car (ie no Fuel duty and no VAT) - they said it was now OK and I have a call ref to prove it if I have to.



My understanding is when you buy oil before fuel duty is paid (ie you have to arrange to pay it to HMRC), you are classed as a producer - this HMRC doc states if you produce less than 2501 Litres/Year you now do not need to pay fuel duty. The VAT team said that if you buy oil from tescos, they are not concerned as to what you do with it (whereas the fuel duty team are, but only above 2500 litres/year).



Keith

keith_b - n/a
3-Aug-07, 08:35 AM
Keith,



Methane - I think some of the tents at a meeting on a Sunday morning would produce a decent supply of the gas.



Keith

Jim Lyne - n/a
3-Aug-07, 09:10 AM
The only trouble about Farmers growing crops for Bio-fuels----------------------------------



We will have no bloddy land to camp and race on.



Jim Lyne

jon_curtis - n/a
3-Aug-07, 01:38 PM
hi keith b



I just spoke to customs, and i can't believe it! you are correct, the law changed on the 30th june and you can run your car on veg oil, use up to 2500ltrs a year, and you dont have to regester. just keep reciepts!



I really can't believe this, they are going on faith that you keep below this value! and no further duty except that all ready paid, from shops applies!



I'm off to lidas to fill up http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif finally the government does something right http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif

keith_b - n/a
3-Aug-07, 07:58 PM
Dangerman,



Good isn't it.



Credit is due to people like Matt Bulba and his colleagues at Blooming futures and many others in his trade who have been quietly lobbying for this for a few years now.



http://bloomingfutures.com/



Keith

Mart366 - n/a
3-Aug-07, 08:11 PM
Sorry ive got to say it.





Petrol WHEEEEEEEEE give me bangs per buck.



let the tree huggers go play.



we only get to race 7-8 times a year, so lets enjoy it while we can:D:D







sorry http://hovercraft.org.uk/images/icons/smiley_icons/icon_smile.gif





seriously though.



unless we go over to diesel or gas, then we don't have much option for the petrol units. Given that diesels run in different ways, will certainly have an effect on racing





BTW how long before people moan about dirty injectors as clouds of smoke / unburnt diesel are dumped around the grounds of some of our more "environmentally" aware courses?





Mart

FanBoyz
12-Apr-10, 10:33 PM
Ok, lets think outside the box - offset, maybe using some familiar technology.

Rather than mess with the craft itself, build a wind turbine, either use it to charge the battery or flog the power to the grid, that's a "carbon offset".

Inverters seem to be available, any decent engineering firm could surely fabricate a mast.. not sure about braking systems or rotors.

Looking at multiwing, the Ws all look the wrong sort of shape, 6Zs look promising but they don't seem to go all that big - any ideas?

broad5186
13-Apr-10, 09:26 AM
another green concern is the composites we use, not just the disposal of, but the carbon footprint of producing the raw material

we've been using basalt fibre with bio resin for prototype race car bodywork but basalt is produced from volcanic rock so the carbon used to melt that must be high

we've also looked at natural fibres like hemp based fibre with bio resins but not tried them in anger yet

lets face it we can make many efforts for craft to become carbon neutral but the travelling and transportation of us and the craft will outweigh any efforts we make to make the sport 'green' just like the F1 KERS systems' a token drop in the ocean compared to the freight, shipping costs, totally floodlit race tracks etc etc

tony

Bob Rennick
13-Apr-10, 01:41 PM
E10 (10% ethanol) is commonly available over here at several petroleum suppliers. However, it has also led to a food crisis in the 3rd world! Corn that was usually meant as feed & food supplies is now being re-routed to the more lucrative ethanol market place!

As one of the earlier posts mentioned, I believe we should be thinking about using the hi-efficiency automotive diesel engines as motive power sources. Modified to run on used cooking oil to keep costs down. Of course, one of the problems is that the smell of the whole race course will cause everyone to be famished and off looking for a fill of fish & chips! However, the small diesels now used in Europe (not over here as our diesel fuel is of lower quality) work extremely well, are relatively light and quite clean running. I know of several people here who have modified their diesel cars to run on used cooking oil. Is it common to see this in Europe as well? Does it only work here because of our lower efficiency diesel automotive engines?

Bob

Ian Brooks
13-Apr-10, 06:53 PM
Your personal carbon footprint can be taken in the round... as an example, I do around 15000 miles a year, around 90% of which is with one 0r two persons in the car. In my big (tow) car, the 90% "one-up" mileage is about 550 gallons a year.

I bought a two-seat eco-car to have alongside the big car. That now does my 90% mileage on about 200 gallons a year - So thats a huge 350 gallons for my hovercraft !!!! Playtime!

So if you want to play with a clear conscience, just compensate elsewhere!

Oh - and I save a bit under 2k per year in petrol costs - more than funds the extra fixed costs of two vehicles. Can't think why I didn't do this years ago.

Ian

John2
22-Apr-10, 04:57 PM
Hello all,

There is no such thing as carbon free energy. The least of all is nuclear fission...but solar is closing the gap.

Sooo anyone up for developing a small powerplant capable of going unrefueled for 20 years or so? :) Gonna need a huge platform.

Trigger has been pushed...


Thanks
J

curtis5420
22-Apr-10, 05:48 PM
its warm enough now, for me to run my camper van on veg oil again, 75% of the fuel i put in my van, is off the shelf at morrisons for 84p a ltr :)

penfold
25-Apr-10, 11:53 PM
I think they add some kind of emulsifying agent which effectively holds the water in 'solution', water droplets of any size tend to cause injector damage(the water boils causing localised pressure fluctuations and breaks lumps off the injector tip and nozzles).

curtis5420
26-Apr-10, 06:15 PM
7 years of running veg oil, in my 1.9diesel golf, with no problems, have exactly the same engine in my van.