The Energy Shed.
This website charts a personal journey I am making into renewable technology.
Part blog, part diary and part notebook to remind me of stuff I have done, it presents a record of my transition into a
lower petroleum society.
It details my various projects concerned with providing domestic heat and power by renewable means, using wood
fuels, solar water heating and a small amount of solar photovoltaics.
The initial desire was to produce my own electricity and to heat my home and business using renewable fuels. The
project has evolved over the last 5 years, and has resulted in the building of a renewable energy workshop, as a self
contained addition to my property.
The workshop keeps all of my renewable equipment under one roof, and represents one way in which a renewable
energy could be bolted on to an existing suburban property with minimal disruption to the existing domestic
systems. Whilst I have chosen to build an insulated wooden shed t o contain the system, an insulated redundant 20'
shipping container might be an alternative approach. In effect - a complete RE solution in a box.
As my back garden is only accessible through an 850mm wide gate and narrow passageway, all equipment had to be
carried by hand, and small enough to fit through the gate.
The shed is connected to the house via a buried 100mm pipe, which carries the insulated hot water pipes and the
electricity cables. If there is a problem with any of the system, it can be isolated from the house systems and fixed
independently, with the house returning to normal grid power and natural gas.
So three years ago, I set out to produce a self-built, combined heat and power system made mostly from salvaged and
The basic technology required for my system has been appropriated from earlier times, when petroleum was in
short supply. Should we have to make the transition back to reduced petroleum lifestyles, I will have covered most
of the ground in advance.
Using a combination of 1930's diesel engine technology and a woodchip gasifier based on designs that were common
place in wartime Europe, I run a 1950's generating set using a combination of waste vegetable oil and producer gas
made from woodchips,
The emphasis of this project is that it not located out in the wilds of Wales or Cornwall, it is done in a home built
shed in my back garden in the middle of suburbia - again proving that the RE system can be applied where space is
limited and without major modifications to the property.
I decided that I was really going semi-off-grid and
achieving a high degree of energy independence
from the utilities. At the same time making use of
renewable fuels in an attempt to lower my
household carbon footprint.
The system I have built based around a vegetable
oil powered home heat and power system which can
offset a considerable percentage of my electricity
and natural gas requirements.
Now in January 2009, I am now able to get copious
amounts of hot water, electricity and heating from
nothing more than filtered waste vegetable oil,
obtained from a local pub
In November 2007, I was fortunate enough to
have wood gasifier expert, Johan Linell come to
stay with me for a weekend, from the wilds of
Johan came over to the UK for a week to help
convert a Toyota Hi-Lux pick-up truck run on
Whilst staying with me, Johan, a keen amateur
filmmaker, took some video footage about my
veg oil Lister CHP system.
Johan has now edited the footage and made a
short movie, now released on YouTube: - Here it
I am a forty three year old
electronics design engineer living
in suburban Surrey.
I have a background in broadcast
low cost electronics, mass
production, electric vehicles and
Here I am pictured in April 2005,
with my first 6hp Lister CS engine
and generator which I
demonstrated running on
vegetable oil at the Kew Bridge
The Lister CS 6/1 and generator
are mounted on a small trailer for
This engine is now in Leeds,
adopted by a Lister friend of mine.
This is not new technology, most of the equipment
would have been familiar to my grandfather's
Taking my inspiration from this old photograph of a
Lister dc generating plant from the 1930's, I attempted
to recreate something similar that would meet the needs
of my 21st century home, but running renewable biofuel,
not fossil fuel.
In an attempt to shift my domestic energy consumption
from fossil fuels to renewable sources such as wood and
waste vegetable oil, the Lister CHP system gives me
access to sustainable heat and power.
Installed in my garden shed, it provides up to 3kW of
renewable electricity and plenty of waste heat for
heating water, my house and my garden office and
Here is my 1951 Lister CS slow speed diesel
engine generator which forms the heart of my
DIY domestic combined heat and power
system. This is an early shot from April 2006
before the unit was installed in the new engine
It is powered by renewable waste vegetable oil.
The diesel engine is adapted to run on filtered
waste vegetable oil and drives a 3kW
alternator, producing sufficient electricity for
my household and business activities.
To make greater efficiency of the energy value
of the fuel, the waste heat from the engine
exhaust and coolant system is captured and
used to supplement my domestic central
The complete heat and power system is contained in a shed at the back of the house. It is connected to the
house via an insulated "heat main" which runs in a trench from the shed to the house.
The engine CHP system, the woodburning boiler and the solar water heater and storage tank are all housed in
the shed. If they are not used at any time, the house can run normally from an efficient condensing gas boiler.
Keeping the systems together in the shed means that all the major components are located in one place, and the
connection to the house is kept simple.
The shed has been insulated to a high standard, so that it will be comfortable to work in, both in winter and
The Lister engine generator has now been running in the shed on and off since October 2007.
It seems to run best with about a 2.5kW electrical load, and under these conditions it will produce about 5kW
of heat in the form of hot water at 60 degrees C, which is more than enough to heat my house, and provide hot
water via an indirect hot water cylinder.
Some facts and figures.
Engine type Lister CS 6/1 built in 1951
Type Single cylinder, slow speed diesel engine with indirect injection
Power Output 4.47kW (6 hp)
RPM 638rpm for 50Hz 230V power production
Fuel Filtered waste vegetable oil
Fuel Consumption 3 litres every 2 hours when running with a 2.5kW electrical load
Alternator Chinese manufactured ST 3kW
Belt Drive HTD Belt 8mm pitch 20mm wide
Heat Output 6kW maximum 60 degrees C, about 330 litres per hour
Gasifier Experimenter's Kit (GEK) Supplied by All Power Labs, Berkeley, California.
Thermal Output 10-12kW
Gas Output 14 Nm3 per hour
Reduction throat diameter 80mm
Fuel Hopper Capacity 20 litres internal, 200 litres external
Fuel consumption 20 litres (3.6kg) per hour
Number and Size of Air Nozzles 5 x 8mm
Fuel Source - Chipped wood waste from local tree surgery businesses
|For More Information:
Ken Boak can be contacted by email by anyone wishing further information on this project.
Since starting on this Lister project, several other Lister engine enthusiasts and their CS engines
have come to my notice. These links describe a few of them. We have recently started a Lister CS
Owners Group, contactable via Yahoo Groups
Following my meeting with Johan, and an
introduction to wood gasification, I
decided to focus the project on generating
heat and power using woodchip waste
from tree surgery waste.
During the course of 2008 with rapidly
increasing crude oil prices, waste
vegetable oil had also become increasingly
expensive, as supplies were bought up by
With diesel fuel peaking at £1.33 per litre
in July 2008 and central heating oil,
electricity and gas also seeing 35% price
rises there was considerable pressure to
find an alternative source of heat and
power for my household.
The solution arrived in early January
2009, - a Gasifier Experimenter's Kit or
GEK, produced in Berkeley, California by
Jim Mason's AllPower Labs company.
The picture on the right shows the basic
GEK, before painting and partly assembled.
A new page has been added for my GEK
and gasification activities.
February 2nd 2009.
In the grips of Winter.
The renewable energy workshop
disappears under a blanket of
The interior remained well
above freezing thanks to the
Six inches of snow brought the
south east of England to a
standstill for three days, with
roads and public transport
heavily disrupted, showing just
how fragile an infrastructure we
From the outset I wanted to build a new workshop, as I had overgrown the two 6 x 8 sheds that I inherited
from the previous owner. With the provision of extra space it was then conceivable that the workshop would
be a convenient place to put the rather bulky components of the RE system. A large inverter, battery bank and
thermal store takes a fair bit of space, not to mention twin Lister diesel engines, and all their associated
The shed concept also keeps (almost) all of the scruffy 2nd hand equipment out of the house, which is beneficial
in sustaining a happy marriage.
The project aim was to provide a renewable energy system appropriate to a suburban environment - and to show
how changes can be made to lifestyles to bring about sustainable change in suburbia.
The system was to be experimental, evolving over a period of time, as a learning exercise in energy independence
- but developed in such a way to minimise the disruption to the normal household heating system - hence the
idea of a "bolt on" extra.
I had the idea of a "renewable energy system in a box" which could be retrofitted to a typical suburban house.
The first idea was a redundant insulated shipping container which securely housed all the equipment, but for
access reasons this was not possible at my property, so I came up with the idea of an insulated, self built wooden
shed, ideal because I wanted to build a new workshop at the same time.
With all the bulky equipment housed in a shed in the garden, and not in the house, and in the case of solar heating
panels and pVs, not on the roof making them easily accessible.
Additionally, the shed was to house a multi-fuel generator set running on either waste vegetable oil or woodgas.
The engine, generator and wood gasifier components are bulky and not the sort of thing you would want in the
From the outset the system was to allow fuel diversity. The majority of homes in the UK are reliant on centrally
generated electricity and natural gas for heating. If there is a future energy crisis, then the systems contained in
the Energy Shed will at least be able to provide heat and power, from low grade fuels such as woodchips.
In a nutshell:
A reorganisation of a suburban lifestyle to become less reliant on petroleum fuels and determine the most likely
transition routes to renewables within the suburban environment.
A household combined heat and power system using renewable biofuels - mostly woodchips from tree pruning
A continually evolving project to provide renewable energy (RE) alternatives for a typical suburban home - where
clearly windpower won't work and the cost effectiveness of photovoltaic panels is questionable.
Preparation in advance for the potential shock of the "Great Unravelling".
An experimental kit of parts, salvaged, recycled and resourced from second hand equipment.
A complete "system in a box" connected to the house by a buried, insulated umbilical of heating pipes and power
cables. Self contained and providing secure storage for the bulky components that form a RE system.
Additionally providing storage and workshop space for those wanting to work from home thus avoiding inefficient
commuting and other work related stress.
"The Good Life" without the vegetables, the goats or Felicity Kendal.
The Renewable Energy
Workshop takes shape in late
The temporarily installed solar
panel contributes hot water to
the house. The shed houses the
hot water store, the batteries
and inverter and the veg oil
In January 2009 a wood gasifier
unit was added to the system
with the intention of being able
to provide combined heat and
power through the gasification
of wood chip waste from tree
The heat pipes and power cables
run in insulated pipes back to
the house in a trench underneath
the decking area.
A Bolt On, Renewable Energy System for a Suburban Home - Using renewable woodchips as fuel.
With the coming of Spring and glorious weather in March 2009, I have decided to give this site a spring clean
and try to organise it better. This page is www.powercubes.com/listers.html and subsequent pages follow the
naming convention /listers_1.html through to /listers_14.html. Other pages will be corrected in due course.
The various "chapters" of this continually evolving project are listed below:
The specification of the Energy Shed as of Spring 2010 includes the following:
3kW Lister Startomatic diesel generator CHP system running on veg oil and woodgas.
5kW pure sine inverter with 16kWh battery bank
150W solar pV for battery bank trickle charging
2kW, 20 tube solar water heater
700 litre thermal store
Woodchip gasifier with 12kW thermal output.
Woodchip burner for supplementary heat.
The output of the generator/inverter is routed to 5 circuits - covering the main high wattage loads in the
house. In the event of grid failure the Lister generator would allow most domestic activities to continue and
give a maintained supply to the two main occupied rooms, namely the living room and the office and provide a
supply to the workshop shed itself.
The hot water output from the Lister CHP system and thermal store is conveyed by insulated flow and return
pipes to a manifold system which links with the domestic heating system. The Lister CHP can supply
approximately 5kW of heat, and the gasifier running in thermal mode can supply about 12kW, when using
about 4kg of woodchips per hour. This heat can be used to keep the house at a comfortable temperature or
ensure that there is an adequate supply of domestic hot water.
A Continuing Experiment in Sustainable Suburban Re-Organisation.
This project is a continuing experiment in suburban re-organisation. It reflects some 5 years of developments
punctuated by the pressures of having to work to pay a mortgage.
In 2004, I was working as an electronic design engineer from my home in Surrey. My project was a device to be
used by the American payphone companies, which was to be mass produced in China. Sandwiched between the
manufacturer and the customer, on three separate time zones, I began to ponder how to restructure my suburban
lifestyle to be more energy efficient and to be less reliant on centralised energy generation.
The starting point for my suburban re-organisation was to produce my own energy, to give our household a certain
degree of grid independence. Whilst not entirely off-grid, I coined the phrase "semi-off-grid", meaning that for
most of the time it would be business as usual - purchasing energy from the utilities but in times of energy crisis
there would be the means to become grid independent - in effect a "Plan B".
Wind power was rapidly proven to be a non-starter in suburbia, and the cost of solar pV was prohibitive for the
sort of power requirements for the average suburban home. I therefore chose to find an alternative means of
producing power using an adapted diesel generator set, which could be run on a variety of renewable fuels
including waste vegetable oil and ultimately wood gas, produced from tree-surgery waste.
So, early in 2005, after returning from New Mexico and Minnesota, and parting company with my previous
employers in late March, I set about building my renewable energy system. The project is now into its fifth year
with many developments along the way.
In the south east of England, suburbia was for many years the normal model for housing development, dictated by
the need to cluster population around transport links, workplaces, shops and amenities. My district was developed
100 years ago, before the widespread introduction of the motor car, so I am fairly conveniently located within a
mile of the nearest mainline railway station.
The property is on a 1/10th acre plot, giving it a much larger garden than is normal these days. This at least gave
me the option of space to build the outside workshop and energy shed in the back garden. The house is robustly
built in solid brick, with fireplaces in each of the rooms. This at least gave me the option of returning to wood
Modern suburbia has been designed around the motorcar, and the high price of land has resulted in much smaller
properties, packed in at about 35 to the acre. It is doubtful whether modern suburbia can be re-purposed for low
New Directions - California February 2010
Following another parting of ways with my central London employers, I realised that daily commuting to
London was really the road to self destruction, so I spent February 2010 travelling to Portugal and the USA in
order to decompress from 12 months in the "smoke". It was a time to think about what I wanted to do next -
projects, which had been on hold for at least the last year.
My week out in California had got me fired up again on wood gas. Converting the Lister engine to run directly on
wood gas and see it perform so well has given me the assurance that wood gas can be made to work for small
scale heat and power production. The dual fuelling would no longer be needed, but I could retain the injector so
that the engine could be started on waste veg oil if needed.
In the last 5 years I have slowly established an experimental CHP system based on the Lister 6hp diesel engine.
Until now, this engine has run on waste vegetable oil, but with WVO getting more difficult to obtain, I realised
that a substitute was necessary. The CHP system is located in my garden workshop, known as the "Energy Shed"
and the heat and power is brought back to the house via underground pipes and cables.
Following the success in California, it's now my intention to set up a complete wood fired CHP system to heat
and power my house. Woodchips are generated as a waste product from tree surgery operations and so there is a
glut of this material produced with no real market. Wood chips can be gasified to make a flammable gas to
substitute for the WVO fuel for the Lister engine on my generator set. This will produce more than sufficient
power to run the house, and the waste heat will be used to provide heat for the house.
A quick calculation suggest that 1 tonne of woodchips will be needed each month of the heating season. This is
about 4 cubic metres of chips, which can be stored in a bunker at the front of the house. A converted wheel barrow
will be used to transport up to 300 litres at a time, down the side path to a smaller bunker near the workshop
holding enough for about 3 days operation. This is defined by the limited access to the rear of the house -
everything has to pass through a 3 foot gate and down a narrow path.
A 200 litre drum full of chips will provide sufficient energy to run the Lister engine for about 10 hours. Spare
electricity can be stored in the battery bank to run my inverters, or converted to stored heat in night storage
heaters. Spare heat will be stored in a 700 litre thermal store, located in the workshop. This will hold about
60kW of heat, which is sufficient to warm the house overnight, and can be topped up from spare heat from the
The Lister will be run from about 8am till 6pm, and with adequate silencing and in an acoustic box, should not
cause a distraction. It's a Startomatic generator, which can be remotely started. By retaining the diesel injector,
it can be started on WVO, switching over to woodgas when the gasifier is fully operational and producing clean
Waste heat from the engine will be used to dry the woodchips, and pre-cook them using a process called
torrefication. This pre-chars the chips, driving off water vapour and volatiles, which improves the gasification
process. The intention is that the Lister and the gasifier will work in close harmony, where waste heat is
exploited in order to maximise the system efficiency.
The 200 litres of chips should produce 25kWh of electricity and 60kWh of hot water. As this household uses about
7.5kWh of electricity per day, the surplus can be used for heating the workroom and workshop.
In February 2010, I attended a
Wood Gasification Workshop,
held at All Power Labs (APL),
manufacturers of the GEK
Over the course of the weekend
we learned how to produce
clean, "engine grade" wood gas
using the GEK gasifier, and also
converted an Indian Lister
engine to spark ignition so that
it could be run directly on
woodgas without the need for
At the end of the weekend we
successfully mated the GEK to
the converted Lister and ran it
for the first time on pure
Much of my system is experimental and it is continually evolving. As of March 2010 the emphasis of this project
has shifted to running the Lister engine generator directly on gasified woodchips. A spark ignition conversion,
proven to be successful in February in California will allow it to use woodgas directly, without dual fuelling.
The latest project update is now on my woodchip gasification page.
Feb 21st 2010.
During a recent trip to California to
attend a Gasification Workshop at
All Power Labs, a Lister type diesel
engine undergoes a successful
conversion to spark ignition.
This allows it to run on pure
woodgas, without the need for dual
fuelling with waste vegetable oil.
Thanks to Mike Anthony, Marcus
Hardwick, Jay Hasty, Darrel Licks,
and all the team and attendees at APL
who helped to make this conversion a
Here's a video of us starting it
up for the first time - taken by
Rogelio, from Mexico, a fellow
woodgas course member.
It should be noted that we had
only just finished wiring up the
spark ignition circuit, the Lister
had been re-assembled with
extra head gaskets to give a
lower compression ratio, and
the ignition timing had been
guessed and was far from being
optimum. Woodgas was being
produced by a recently upgraded
GEK gasifier located to the
right of the Lister.
Darrel is cranking the engine
whilst Mike Anthonycontrols
the mixture valve and the
We had spend two days making
gaskets and spark ignition
circuits, and it was now Sunday
evening and the end of the
The events that unfolded in this
video were an unbelievable
surprise to us all.
February 21st 2010, All Power Labs, Berkeley, California.
Spark ignition converted Lister engine runs on woodgas for first time!