Look out for an old large lawn mower and adapt the motor. If you want to
buy a new motor, Honda is selling "raw" motors ready to run with a tank,
ignition and so on,
https://www.kart-schuette.de/motoren/honda-motor-gx25-nt-stsc.html

Cheers,

Shure

PS: I'd like to see an electric conversion of the hydraulic power cube!

On 19 April 2012 21:25, Angel Imaz <an...@hiruki.eu> wrote:

Great news:) Are you considering the horse power depending on the
application you want to use the PC for. 17hp, 28hp?

Best,
Will

On 20/04/2012, Alex Shure <etemu....@googlemail.com> wrote:

On 23/04/2012, root <alve...@gmail.com> wrote:

I guess 12 kWh of energy is just not enough. That is less than one hour of
field work, just to carry another 300kg of batteries around and swap the
package? I encourage FeF to use Batteries and renewable energies as much as
they can, they have a pretty high budget now. But I guess it's just to
expensive for the John Doe over here. Petrol is still too cheap?

Cheers,

Shure

On 23 April 2012 10:12, Will Cleaver <willclea...@gmail.com> wrote:

Hydrogen technology could also be something that if open sourced..could
help solve the oil dependency. I have been  wondering if that could be
possible.

Like the idea of powering with electric batteries,more than oil. Anyways we
could have other resources like bioetanol form algae, that it's something
that could be achieved.

best

ezequiel

2012/4/23 Will Cleaver <willclea...@gmail.com>

Sorry guys I just noticed that in my last email I claimed bio-mass was a
fossil fuel. I think my typing hands got carried away in front of my
thoughts. Anyhow excuse me.

Best,
Will

On 23 April 2012 09:23, Ezequiel <vha...@gmail.com> wrote:

Just to give an idea of magnitudes,

The BOM <http://opensourceecology.org/wiki/Power_Cube/Bill_of_Materials>for
the current power cube recommends a 28Hp engine.
That's equivalent to a 20kW engine.  Wikipedia gives a 50 Wh/kg upper bound
on Ni-Fe battery energy density.
So to operate during 1h, we would have to carry Energy-Used /
Energy-Density = 20,000kWh / (50 Wh/kg) = 400kg.

Of course that's pretty coarse, add in inefficiencies, fast discharge, ...
and you're talking about half a ton battery for 1h of work! 8-/
I guess there are various things that can be changed and improved.  Lighter
vehicle, perhaps a mix of biofuels + electric for different things (arms,
wheels, etc)?
but there's no denying that gasoline is pretty amazing:  13,000 Wh/kg  vs.
40 - 70 Wh/kg of batteries!

On 23 April 2012 10:33, Will Cleaver <willclea...@gmail.com> wrote:

- Mark

On 4/23/2012 4:12 AM, Will Cleaver wrote:

For Extremadura I'd look at olive oil slurry (what's left over from
producing the oil) as an energy source. Apparently it makes pretty good
biodiesel, amongst other things, and there's an absolute shedload of oil
production in the region. Doesn't actually seem to be much else...

I'd be very happy to collaborate with the development of a diesel
engined powercube.

Choose the right engine (very important) and it would not be a big
problem to make modifications to make it multifuel.  That is, run on a
wide range of oils, including olive oil!!  (without having to chemically
modify the oil into biodiesel)

see http://vegburner.co.uk/oils.htm for some info on non-fossil fuel oils

I've spent far too much time during the last 12 years doing r&d work on
the modification of diesel engines to run vegetable oils.  It would be
nice to make some good use of that knowledge.

The most up-to-date info I posted on the web is now at
http://www.appropedia.org/Pure_plant_oils

Diesel engines are bigger than petrol(gasoline) engines of the same
power output.

If there is interest in going down this path I guess the first thing to
do would be to identify a suitable engine as this is likely to effect
the dimensions of the power-cube frame and the sizing of the hydraulic
pump.  Unfortunately most small diesel engines are not particularly
suited to such modifications (although there are some that are).  The
main consideration, that would make multi-fuelling easy, is that the
engine uses indirect fuel injection - most small diesel engines do not.

It would be worth looking at small Kubota engines as most (if not all)
use indirect injection.  I'm on a very very slow connection so cant look
at the pdfs linked from here -
http://www.kubota.co.uk/prdct.asp?PageRef=81 .
Most of the Kubotas are however liquid cooled engines.  Which further
complicates the build (need to fit radiator etc.) although it also would
make the possibility of using waste engine heat much easier to achieve.  
It would be quite straightforward to have hot liquid output connections.

Kubota engines are very good engines - so unfortunately they are not cheap.

On 23/04/12 12:41, Daniel Connell wrote:

As for an electric power cube, the idea of combining a motor and
battery bank in the same module is quite absurd given that you will
have to physically change out batteries so frequently. It makes sense
for a liquid-fuel combustion engine, where you can simply open up a
fuel cap on the cube and pour more in without changing anything else
on the machine, but the design needs to be appropriate when using
battery energy so that you do not waste material on excessive
redundant electric motors and energy on changing them.
It is better to use a few motors with different windings for various
applications that have different torque and rotational speed
requirements, so when designing for modular electric powerplants, we
ought to have separate motor and battery blocks that can be hooked up,
especially in such a way that several small 25-50kg battery blocks
could be installed in parallel to provide for the different energy-
consumption requirements of larger machines (such a weight would
enable a strong operator to load a few of them onto a tractor safely,
but once you're talking about 100kg+ blocks, you will need specialised
machines to load them for safety; think http://youtu.be/jk3Z-MVoUg4?t=1m
only with battery blocks going a shorter distance into a tractor).
Such battery blocks could each have a cheap photo-voltaic solar panel
on top to keep them trickle charged both in operation and while being
moved between machine and charging station.

Whatever power source we use, in the near future as it looks like
we're in for a struggle to replace fossil fuels with renewable energy,
we may no longer be able to afford the luxury of running tractor-
driven ploughs over fields and then spreading artificial fertiliser on
them, so we will probably have to use chiefly no-till agricultural
methods, such as using perennial staple crops (http://
permaculture.org.au/2012/02/25/perennial-staple-crops-of-the-world/)
and aquaponics (where some spare fertiliser is available). Off-grid
heavy energy uses to have in mind ought to be things like one-off
landscaping with front-loaders, to create foundations for buildings
and waterways for food production, but not so much driving a tractor
in stripes over a monoculture field if the designs are meant to be
forward-thinking.

On Apr 23, 9:23 am, Ezequiel <vha...@gmail.com> wrote:

This is the future I see.

Sent from my iPhone

On 24 Apr 2012, at 23:51, 4ndy <andrew.james.drumm...@gmail.com> wrote:

Following discussion here about power cubes I looked through the OSE
wiki and read a fair bit about the power cube and developments,
particularly Tom Griffing s log which details his ongoing work on the
power cube design.
http://opensourceecology.org/wiki/Tom:_Dallas_Log

I've also taken on board discussion here about the possibility of
electric power cubes.

I'm following Toms path and working on a concept for a modular power
cube system.

Combustion engine or electric motor couldh provide power.
This would drive hydraulic pump, electric generator, water pump or have
a direct mechanical coupling to the machinery to be powered.

I've also been considering the idea to combine modules to make a
electric/combustion engine hybrid power unit.

I've put together a concept sheet to illustrate ideas.

http://opensourceecology.org/wiki/File:Modular_Power_Cubes-small.jpg

This hybrid power unit would also require the addition of a clutch
module between the engine and the motor/generator which I have not shown
on the concept sheet.   Alternatively it could be achieved with separate
generator (attached to engine), electric motor attached to whatever is
being driven and battery bank.

I've shown a system that uses combustion engines with horizontal drive,
rather than having the drive coming straight out the bottom of the
engine as the existing OSE power cube does.  This, I think, offers more
options for coupling and more power unit options as engines in this
configuration are more common.  It should also make it easier to couple
cube modules as they can be wheeled side by side and coupled together,
it would not be necessary to lift cubes on top of each other.

IMO, the powercube concept is seen overly positive in the OSE
community. It has some merits, but also very severe weak points. I
don't think it will andshould become the universal drive unit for OSE
machinery.

Just to mention some weak points:

1 Scalability
The powercube concept depends on the ability to quick-attach it to
different machines. This limits size and at most the weight of the
powercube. To handle it, its weight must be clearly below 50kg - else
You need a crane for installing and deinstalling, clearly no quick-
attach and not practical.
Therefore power of the powercube wit a gasoline engine will remain in
the magnitude we have today - 25 hp more or less. No chance to carry a
100hp engine around...

Also some planned designs of FeF with the use of several powercube to
get the needed power are impractical. In the wiki they are talking
about a truck design with up to 10 power cube. I wonder if anyone
wants to buy such a truck?
Its no cheap concept, and it will cause high maintenance and repair
cost. Repair costs with powercubes will be high anyway. You can expect
a large diesel in a tractor to do 5000 or 6000 hours of operation
before major repairs/overhauls are needed. For the small fast-running
gas engines in the cube today I expect at best 1500 or 2000 hours.
So if Your commercially built truck needs an expensive engine repair
after 5000 hours, with the OSE 270hp-truck You will already have
wrecked 25 -30 "Hondas".
I would consider any design with more than 2 powerubes impractical.

2. Alternate Fuels
Alvaro has already calculated the battery weight of an electric power
cube. If You want to keep the weight below 50 kg, battery capacity
can't do any work.
There's another point to consider. Whatsoever is the sense of an
electric power cube?
Much cheaper and more efficient to replace the hydraulic motors in the
machine with electric motors and attach a battery pack. Electric
motors have better efficiency and You don't need a hydraulic pump.
Electric motors are cheaper too and standard motors can be found at
every scrapyard.

3. Steam power cubes
As long as we want to have a lightweight quick-attach powercube You
can carry around, steam won't work. Steam engines are heavy compared
to their horsepower, they need a larger fuel storage (if You don't use
oil) and water storage. How much power do You expect You can get from
a 40kg steam pwer cube ???

Final conclusion is, for mobile machinery energy has to come from oil.
Or ethanol or biodiesel, maybe hydrogen in the future.
Just to take up Alvaro's calculation for a farm tractor. It should be
at least capable of 4 hours heavy work without recharging/exchanging
batteries. A 100hp-tractor develops 74kW, for 4 hours thats 296,000
Wh. With 60 Wh/kg, the batteries account for 4950kg and thats more
than the complete weight of a 100hp diesel tractor.
My conclusion, forget batteries! They might maybe work in a
lightweight passenger car with low range, but not for machines doing
heavy work like tractos, trucks, locomotives and construction
machnery.

Mike

On 23 abr, 12:00, "Alvaro F. Boirac" <alphy...@gmail.com> wrote:

Hi Root,

No matter what the assumptions are, gasoline is incredibly more energy
dense than batteries. [here's a chart to illustrate
that<http://www.cenit-del-petroleo.com/saber-mas/#alternativas>
]
An internal combustion engine extracting 5% of the energy in gasoline would
still get  650 Wh/kg. (And no battery can beat that).

I'm not advocating it.  It's just a remark.  Chemical energy is F*%$S
dense! How I did the calculation is very transparent:

"20kW engine working at full power for 1 h"

Is this how a tractor works in real life?  No.  But that's not the point.
The point is that Batteries are heavy.  So sucking 28Hp out of a battery is
not a good idea.

Are you assuming the combustion engine is working all the time at 100%

Oil will eventually become very scarce and expensive.  So perhaps we need
to rethink the problem.
Can we work the land with 10Hp? Do we need a vehicle? How else can we use
electricity? etc ...

Could we have a small grid where solar and wind are hooked to a plow that
moves over the fields?
Hydroponics?  Some other way of cultivating?
Maybe vehicles should be very light and electric.  And agriculture and
machinery should not be on them.

On 2 May 2012 13:03, root <alve...@gmail.com> wrote:

always good to read your words mike and alvaro too!!

i wonder what is needed to start a new GVCS development, we could be
starting to move forward OSE.

we face enormous problems..as the main..energy, and that's something OSE
seems not be focused or worried. I think that food production can be more
effcient than it is right now..so heavy machines for current agricultural
systems would not be so requiered, as one thing that must change is global
trasnportation of water in form of food..for locally food production.

Bio-ethanol from algaes, biodiesel  from Jatropha, one day hydrogen
together with complete a re-engineered of system production that avoids
planned obsolescence..can help to transition the current energy
requierements for our current way of life.

Best regards

Ezequiel

2012/5/2 Bastelmike <mischa...@yahoo.de>

AGRICULTURE

Our current agriculture has a large focus upon large scale energy (and
often water) hungry industrialised mono crop systems.  The development
of these methods and the information and debates around the suitability
and alternatives to this system are highly influenced by very powerful
actors that profit highly from, and have vested interest in, maintaining
this system.

We use a very small number of plants, considering the number of edible
plants in the world, to provide the bulk of our food.  Almost all our
food comes from annual plants, which requires regular working of the
soil and is often destructive of soil structure. Many of us also eat a
lot of meat, which is generally produced using highly questionable
methods - ie most beef in England, and I suspect elsewhere in Europe, is
fed (at least during the winter), largely on milled soy beans, which are
mainly produced in Latin America using highly destructive methods of
agriculture.

Industrial systems of agriculture are often damaging to-

The land - through irresponsible farming techniques (aiming for top
financial returns) soil is degraded (soil only fed with chemicals,
gradually loses structure and the countless living organisms that give
the soil vitality) or lost (through erosion).  Countless acres of good
land have been and continue to be lost due to short term interest.  This
land degradation sees a constant pressure for opening up new lands for
agriculture and is a significant driver to the massive illegal forest
clearances that are occurring across the globe

The environment - As well as damage to the soil much damage is done to
waterways (ecosystems ruined by agricultural chemicals, particularly
nitrates, washed from the land, much higher risks of flooding due to
lack of water retention on land farmed using industrialised methods ),
wildlife (habitat destruction), air pollution (from the fuel burnt to
farm and, often, needlessly transport the products.)

Communities - industrialised monoculture agriculture methods favour
large scale operations often with few, low paid jobs (often seasonal).  
Many rural villages have been left deserted or the houses have become
the weekend retreats for rich city dwellers.  Big businesses make large
profits from our current food production (agro industrial companies) and
distribution (supermarkets) systems.  These gains are made with huge
costs to other small economic actors based within our communities (where
have all the small grocery shops gone??).

Economies - looking at the real economy (beyond the marker that
supposedly represents it, money) and the interlinked nature of all parts
of it, our 'free' market led system of industrialised agriculture
favours large operations, by companies  (often with 'absentee' owners -
eg. pension funds, financial investors) who have little understanding
(or care?) of the land, the people who work the land or of food quality,
just for quick financial returns.  The resilience of this model is
highly questionable.  The current system sees significant, largely
invisible, subsidies and workers who receive extremely low wages.

Seed/plant and livestockdiversity - A relatively small number of plant
varieties and animal breeds are considered suitable for our industrial
agriculture and food distribution systems.    Due to the concentration
of use of these plants, and at times legislative pressure, numerous
plant varieties have been lost or become difficult to obtain.  The
destruction of ecosystems, often due to clearance from industrialised
agriculture has also seen loss of genetic diversity.

I just got these on the first page of a web search for information that
offered an alternative perspective to the one most often presented  -

http://ipsnews.net/news.asp?idnews=55924
http://www.guardian.co.uk/environment/2011/jan/13/world-hunger-small-...
http://www.pan-uk.org/pestnews/Issue/pn33/pn33p23.htm
http://www.population-growth-migration.info/essays/woodwardorganic.html

Even within our current distorted economic system and with the high UK
land prices small scale sustainable farming can be 'economically viable' -
http://ecologicalland.coop/projects-small-successful

Just yesterday I was reading a book called 'Tree Crops' written in 1950
which detailed the massive soil destruction in the USA due to
industrialised agricultural methods (huge amounts of soil being washed
away leaving highly fertile land barren, within years) and proposed
development of tree crops to help counter this destruction.  The author
had worked on this for some time, travelled the world to see
agricultural systems that used trees and seen (surprisingly quick)
interesting developments from small actors (often private individuals).  
He despaired at the lack of interest from government in supporting or
working upon the development of such ideas and the difficulty in
persuading others to try out new methods of agriculture.  Sadly it
appears that not much has changed since this book was written.

Regarding Mikes comment "And without energy for farm machinery
agriculture will need all the workforce of the population, leaving no
time to produce something besides needed food."  I dont think this is
true.  It wasnt true before the adoption of the tractor and we now have
a far greater understanding of plants and soil. I've visited a community
where the people had access to land without the necessity to pay rent or
service the loans necessary to purchase land.  With very very simple
tools, and at times not best practice for soil, water and weed
management, or much thought to alternative crop choice and combinations,
the people managed to produce more than enough food for their families
working less than 4 hours a day.  This left plenty of time for other
activities -  other production for market, leisure, and cultural
activities etc. etc.

ENERGY

Our societies have largely developed with an assumption of continuous
'cheap' energy.  Its hard to understand, and picture, exactly how much
we use and what is necessary to obtain this energy.  I think much of
this energy is expended unnecessarily and that we can still live
comfortably using far less energy than we do today.

The term 'modern comforts' will mean different things to different
people.  I guess I live in an unusual 'modern' way, that many would not
consider comfortable, but I do.  Likewise I would not be comfortable
living in a way that many people would consider 'comfortable'.  I guess
that studies of world happiness bear some relevance to the question of
comfort (can you be comfortable but not happy?).   The energy hungry
consumerist lifestyle of 'developed' nations clearly does not lead to
happiness.

MY CONCLUSIONS

Bearing all this in mind what systems and tools should we be exploring
and developing.  How much energy do we really need to use?  For what?  
Can we do things differently and use less, yet receive a satisfactory
outcome??  I think we can but that it will take huge shifts in the way
we organise ourselves (eg. replacing our housing and agricultural system
with less energy intensive and more resilient alternatives) and for many
it will require time for them to adapt to the differences.

I think that a more sustainable and resilient agriculture system would
not depend so heavily on the large machines that are used today - the
larger machines are a product and promoter of the logic of industrial
monoculture agriculture.  Smaller machines are likely to be more
appropriate in many situations.  In Colemans classic book 'New Organic
Grower' her details the methods he uses for effective food growing.  He
clearly thoroughly enjoys his work and experimenting with different
methods.  He shows how it is possible for an individual to grow using
novel methods and tools.  The only powered tool he advocates using is a
walk behind tractor - these use small engines.  This tractor is used
reasonably infrequently.  Just looking for a link and found this - which
states he now uses a compact loader tractor - I've got an old edition of
the book)
http://www.tractorbynet.com/forums/1442944-post181.html

" Coleman found the optimum to be about 2.5 acres per grower - enough to
produce quality vegetables for 100 people."
http://s.coop/kn3o

I quite like the concept of power cubes.  The fact that a number of
machines can share one engine (or possibly a store of energy -
batteries) that can be easily transferred or replaced by an alternative
offers a number of benefits.  It is not necessary to have an engine
fixed to each machine - machines that may often sit unused.

I think that it is possible to design a power cube system that uses
larger power cubes that can be wheeled, or carried (by LifeTRAC), from
one machine to another.

http://opensourceecology.org/wiki/File:Modular_Power_Cubes-small.jpg

It would involve some thought to facilitate mounting the power cubes to
vehicles - the lifetrac could have a cradle that lifts a larger power
cube up from the ground.

While developing the idea for power cubes with wheels with powered drive
I began to think that with big chunky wheels, what you would have, would
be approaching a walk behind tractor.  Some walk behind tractors have a
range of tools that can be fitted - some have PTOs (power take offs) for
powering other machinery.

That's a long post and its nearly impossible to answer all aspects.
Not all arguments are wrong but some are based on prejudice or missing
information.

In fact we are using at most annual plants for our food, but it looks
like not many trees and perennials offer food for humans, thats
edible, tasty and suitable as basic staple for humans. Even in areas
with chronical food scarcity, people prefer food from annuals, and
only in emergencies start consuming fruits from trees, roots, leaves.
So there seems not to be much possibility to use more perennials. Most
plants offer not much nutritional value for humans even if they are
not poisonous to us, basically we only eat seeds, roots and tubers,
combined with animal products.

Industrial systems as You call it, I would call them large mechanized
farming, are doubtless sometimes damaging to the soil and environment.
But You have, purposely or by neglect forgotten to mention the large
soil and environmental degradation caused by non-mechanized small-
scale peasants farming, Darren.

One area of large-scale soil and environment degradation and
desertification is the sahel on the southern fringes of the sahara in
Africa. Claiming this degradation to "industrial" is clearly not
telling the truth. There are only a handful of large operations in the
area, mostly mismanaged state farms, leaving nearly every acre to
smallholders and pastoralists. And the numbers of tractors in working
conditions in these countries can be assumed to be less than one per
100 km², therefore You can't call it mechanized farming.
Nevertheless the rate of soli degradation, deforestation and
desertification is prob the largest of any regions of the world.
Obviously there is something wrong with Your thesis, that it is
industrialized farming, that does the largest damage to the
environment. It is the small-scale farmers and the herders who are
devastating the Sahel !

Deforestation is another example. There are examples of large-scale
palmoil plantations in Asia, that are responsible for heavy rainforest
clearance. But there are enough different examples in the tropics.
In Brazil most rainforest clearance is done manually by peasants, with
timber industry being another reason for deforestation.

And the picture is even more different from Your view if You would
have looked at the sustainability of land use. In brazil, poor
peasants clear plots with burning vegetation to crop that plot for not
more than three years, until natural fertility of the soil is
exhausted. After that period they abandon these plots to clear new
land...
The large soyfarms in Brazil don't abandon their land after a few
years, many of them are now operating for more than 20 years and
there's no proof that yields are declining because of land
degradation.
So, what type of agriculture is more damaging ???

Mike

Yes sorry, I got into mega-rant mode.... it was never meant to be a full
analysis of the situation, just presenting some facts that I thought
were important.  With out doubt any one commentator will have some kind
of bias.  Also nobody has all information.

Funnily enough I watched a film last night that a friend had lent me -
'Dirt- the movie' this examines soil and the way we abuse it. No doubt
once again the information presented has a bias - but some interesting
facts are presented.  Someone said that we have lost 1/3rd of our top
soil in the last 100 years - not sure if they were talking about the USA
or the world but that is a worrying statistic (I'm guessing its
true??).  I also suspect that the widespread use of what I've referred
to as industrial agriculture has played a significant role in the
development of this statistic.

There are perennials staple crops and work on improvements - although
they dont often get the attention that they probably should.

eg.

http://en.wikipedia.org/wiki/The_Land_Institute
http://permaculture.org.au/2012/02/25/perennial-staple-crops-of-the-w...

No doubt once again there may be some bias, things may be over hyped -
but that doesnt mean that these crops dont merit further investigation,
research, improvements.

I'm not saying we should discard the use of annuals just that there is
an over reliance on annuals and especially a small number of annuals .

The book I mentioned in the last post 'Tree Crops' was written in 1950
by someone who could not be classed as a hippy or a back-to-the-land
type.  He uses a very scientific method to asses the situation and
examine alternatives.  Much of the book examines tree crops that are
suitable (or could be suitable, as with selection many would see
dramatic improvements) as animal fodder crops.  He talks about replacing
the endless acres of corn monocrops with 2 layer agriculture growing
trees and other stuff between rows.  Also using tree crops in areas that
are not suitable for mechanical cultivation - hills (where, with
cultivation you get terrible erosion), rocky areas etc.  As fodder crops
there is no need for harvesting as the animals would be let loose
amongst the trees as the fruits / nuts / seeds fell.  He examined
working examples of this.

His vision is of a mixture of trees and what I would call industrialised
agriculture where suitable.  Personally, I'm reasonably convinced that
relying on high energy input agriculture is not good - for the various
reasons I stated in my last mail.

I suspect that the reliance on annuals and the necessary tillage while
not looking after the soil has a large part to play where small scale
farming leads to soil degradation.  In warmer regions, turning excessive
animals onto land that is poor for agriculture (possibly because it has
been degraded through soil mismanagement) is a good way of making desserts.

Over farming (lack of access to enough suitable land) often plays a
significant role in land degradation.

There are examples of people claiming back the desert, land that had
been written off as forever dead, by using clever plant combinations and
methods to gradually rebuild the soil.

It is of course possible to get good yields over a long period using
industrialised methods given the right conditions.  I must confess I've
never really looked into this.  Is this likely to continue indefinitely
or are there significant depletions that will eventually cause
unavoidable yield decreases?  I guess that analysis of the soil
composition and volume would answer this question.  Having said that, as
I stated before, I think there are plenty of other reasons to turn away
from industrialised monocrop farming other than soil health.

Created a page on the OSE wiki about modular power cubes concept - which
pulls a few different peoples work together.

Also noticed that Marcin posted this video about plumbing smaller power
cubes together..
www.youtube.com/watch?v=kvpaywBfHQo&feature=plcp

Alex,

I've not looked much at couplings.  Tom Dallas suggested using tractor
quick release PTO couplings
http://www.drillspot.com/products/58359/Dayton_3YB45_Pto_Quick_Coupling

Jamie,

I would be up for having a meeting.  I would really want to be looking
at collaborating with a number of people and not doing the majority of
the organising work before I would want to commit to getting involved in
such a collaboration.

I guess that this would mean that for the project to happen, with a
reasonable rate of progress, at my space others would have to be living
reasonably locally to Brighton (its some distance outside of Brighton
and their is no public transport that gets very close to the location).

Christopher said,

Do have any rough thoughts of (diesel) engine cost and weight?

-------------------------------------------------

Its going to be noticeably heavier than a petrol engine.  If this is
going to be an issue or not I suppose depends on why this is a concern.  
As I understand it the existing powercube design is not very easy to
move using man power (I have noticed complaints about the difficulty of
having to man handle powercubes)  issues of moving can be designed around.

Its also going to be noticeably more expensive to buy and engine. It
would of course be possible to source a used engine.

For some more info/ideas  see my old post copied below

I'm not sure about the vertical drive, my guess would be that it was
what was readily/widely available at the right price in the power range
that was thought to be right.

I appreciate what you are saying about time spent developing the engine
vs. doing CEB work.  I dont see this as being much more work than
setting up for a different (horizontal drive?) petrol engine. Could just
run diesel fuel to start and the veg modifications happen later (with
the right engine these modifications can be easily done).

I see the development of a small stream engine as being a major bit of
development that would take a long time to get a stable product -
something that I'm not sure I would want to get involved with at this stage.

I would however also be interested in a collaboration on a UK petrol
engined powercube project - but my enthusiasm is not as great and my
participation levels would reflect this.