Homemade Power - A Vegetable Oil Fuelled Generator
Update - April 2006.
This page reports on some of the more recent progress on my veg oil fuelled generator project.
In early April, the shed was tidied out to make room for the engine and inverter cabinet.
An experimental exhaust gas heat exchanger supplied by colleague Mike Wilkinson was installed and
Once Paul and I had tidied out the old shed, and got rid of some junk, there was then room to install the
Lister generator set, slightly more permanently - or at least until I got the new shed built.
The task list was as follows:
Tidy shed to make room for genset.
Bolt the baseplate to the shed floor using concrete anchor bolts
Fit an exhaust system - an old car silercer salvaged from an exhaust centre
Wind an oil pre-heater coil around the first part of the hot exhaust
Install a temporary cooling system
Fit the dc starter motor and connect in via auxiliary belt drive
Wire up the inverter and battery set
Plumb the cooling system into the house heating
The engine is coupled up to a 3kW alternator using a toothed belt drive. This allows the engine to turn
the alternator at 1500 rpm which is the correct speed for 50Hz UK mains electricity.
The diesel engine uses between 1 and 1.5 litres of fuel per hour, when providing 3kW of electrical power.
One quarter of the fuel energy can be converted into electricity, and about half of the remaining energy
can be captured in the form of waste heat and used to heat water.
Running the engine for 5 or 6 hours per day will provide me with all the electricity we need and this is
stored in a battery bank, which provides power throughout the remainder of the day.
Waste vegetable oil is readily available in the UK from pubs and restaurants, and there should be no
difficulty found in obtaining the necessary supplies for the foreseeable future.
This photo shows my Lister engine, a
1950 Lister CS 5/1 6hp diesel engine
coupled to a 3kW Chinese alternator
using just ordinary vegetable oil as fuel.
The engine was purchased from ebay for
about £250 or US$450
The engine is quiet enough to be run in a
basement, garage or shed and the waste
heat can be used to heat your home!
In April 2006, this engine and generator
were installed in my 7' x 9' shed as the
mainstay of my Hombrew Power system.
A temporary water cooling tank has been
arranged to allow the engine to be run
for short periods.
Soon it will be connected into my central
heating system to provide up to half of
my winter heat requirement.
The engine and alternator are bolted
down onto a 48" x 24" fabricated steel
baseplate previously used on a Lister
Following some spare time over Easter,
Paul and I finally got my 6hp engine and
alternator installed into the shed.
Shed is a bit of a misleading description,
because really it's just a nice level 7' x 9'
shed base, with a very tatty 3 sided shack
keeping the water out.
The shed is going to be replaced and a new
purpose built engine shed and workshop,
double skinned and heavily insulated
which will act as acoustic cladding and
also thermal insulation. The outside of the
shed will be clad in shiplap boards to
match the other new shed. The roof will
allow my solar panel tobe mounted and
face south south west.
On the Wednesday after Easter, I finally
got the Startomatic base anchored to the
floor with 10mm expanding bolts. I had
hoped to use 12mm bolts, but drilling the
20mm diameter hole in the concrete
would be almost impossible without a
special drill and diamond core bit. I
settled for the 10mm bolts, which only
needed a 16mm hole - and even that gave
The engine now needs an exhaust silencer,
cooling system, vegetable oil fuel tank
system and heat exchangers.
The blue plastic barrels behind are part of my rainwater
storage system. I collected over 600 litres in just three
wet days in early April.
The belt drive uses an
8mm pitch, 20mm wide
Gates GT3 belt.
The engine pulley is 80
teeth and the alternator
pulley is 32 teeth. The
belt drive will have a
guard fitted as soon as I
have finished the rest of
the mechanical work.
The large cream
houses my batteries and
inverter system. It is
rated at 5kW.
Rear view of the alternator showing the
screw terminals for the mains output
connection! These were used for testing
purposes only and will shortly be replaced
with a UK approved 16A splash-proof
The engine and baseplate are now bolted
down to the concrete floor using
substantial 10mm anchor bolts.
The 1950 6hp Lister CS engine and alternator mounted on
salvaged Startomatic fabricated steel base. Engine purchased
from Ebay for about £250 (US$ 450)
Detailed view of the anchor bolt.
These used 10mm loose bolts and
needed a 16mm diameter x 80mm
deep hole to be drilled in the
concrete. This was quite a challenge
for my humble Bosch 600W drill. In
future I will hire an Kango and a
proper diamond core bit.
The engine shed photographed from the open side. On the right is the 5kW
inverter and 10kWh battery storage cabinet. Woodburning boiler on the left.
Running on Vegetable Oil For the First Time! - April 22nd 2006
The engine was fairly loud with the
primitive exhaust pipe - so I scrounged a
second hand exhaust from the scrap bin at
my local exhaust centre (Kwik-Fit). This
had a silencer and a huge expansion box and
was off a large GM/Opel vehicle.
I hastily fashioned a coupling that would
mate with the exhaust manifold flange on
the cylinder head and hoped that I had a
reasonable seal with not too many holes!
I then wound the vegetable oil pre-heater
coil around the first 120mm of the exhaust
where it connected to the flange. This coil
is made from 16 turns of 6mm OD annealed
copper "microbore" tubing. It coiled very
well without kinking around the 54mm
diameter exhaust pipe. If you use 8mm
tube - you must use a 63mm diameter
exhaust to avoid kinking.
The fuel line was then connected to the tank
and the fuel-filter and added a litre of
vegetable oil to the last few drops of diesel
that were in the tank.
Having bled the air from the fuel lines, I
started up, and was delighted to see that the
engine settled down on its new diet of
I loaded up the alternator using my 2kW
kettle and soon was boiling water. The
exhaust oil pre-heater works really well,
the oil leaves the pipe really quite hot.
Once the engine is up to temperature, the
heat from the cylinder also helps to thin the
oil by heating up the fuel filter housing - a
large lump of cast iron.
The exhaust pipe and silencer were
cobbled together from a scrap car
exhaust. Some exhaust fittings
actually have the same flange fitting
as the Lister with the holes on 92mm
Under load the whole exhaust gets
too hot to touch. There is a lot of
heat energy in the exhaust gases
which must be recuperated using an
exhaust heat exchanger. See below.
However, I was impatient to get the
engine running with the exhaust so
came up with this temporary
It is temporarily resting upon my
Austrian woodstove boiler another
renewable project needing some
Next, I put my carpentry skills to
good use and made up this large
acoustic enclosure to house the
It is approximately 1600 x 1200 x
800 mm,and made from 18mm
exterior grade plywood. It will
then be lined with 75mm thick
As you can see - it is a significant
portion of the size of the shed.
It will not be used until I have
the new shed constructed and the
new isolated concrete engine
Here we are running on vegetable oil
with the kettle steaming merrily on the
left hand side.
The water tank on the left was made
from an old propane gas bottle, and is
sufficient to allow test runs of up to two
hours or so. Later on a 120 litre
heatstore tank was added. See below.
The engine is happiest producing about
2.5kW of power, but will produce 3kW if
The battery bank will allow the engine
to run on full load for 4 or 5 hours per
day, charging the batteries. For the
remainder of the day we run on the
inverters and battery power.
Here is the new starter motor coupled to the alternator by a second belt drive.
The starter motor is rated at 6kW, which is half as much again as the engine. It
will happily start it from cold when run from a 36V battery bank - below.
In late June, Tim Dawson-Stanley
visited me from Tang, central
southern Ireland, and got me set
up with a proper vegetable oil
A 250 mm round hole was cut in
the top of a blue plastic drum
with a jig-saw. A sheet of
plywood big enough to make a
lid, had a similar size hole cut in
The filter bag was fitted in place
using a plastic plant pot that had
the base cut off.
A plastic tap was fitted to the
front of the drum about 200mm
up from the base, and a 10mm
bold threaded in and sealed with
a bit of plastic pipe to make a
water drain plug.
Below are a couple of shots of the
filter bag, how the neck is
mounted, and some of the
detritus that remains in the bag
after oil has been poured through.
Join the Lister CS Owners Group - Hosted by Yahoo Groups
Links to my other Lister Pages
Since starting on this Lister project, several other engines have come to my notice. These links describe a
few of them.
The Only Way Is Out! The new exhaust gas heat exchanger, supplied by Mike
Wilkinson, makes an exit through the shed window.
The output from the inverter was a very pure 50.00Hz sinewave of 237V rms.
The inverter consists of two modules rated at 2.5kW. One module ran my 3kW
immersion heater without drooping in voltage or frequency!
A salvaged 120 litre hot water cylinder was used tomake a local heatstore for the engine. Shown here
uninsulated, insulation was added later. At night, the hot water in the tank reverse thermosyphons
through the engine block and keeps it warm, allowing much easier starting the following morning.
Battery charging direct from the 6kW dc generator - seen here producing
102.9V at 23.8A (2450W)
The heatexchanger was lagged with rockwool and thermometers set up at its
inlet and outlet. Below: water inlet temperature 33.5C, outlet temperature