green building magazine - hydrogen supplement - spring 08
TRANSCRIPT
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In this special feature, regular contributor to Green
Building magazine, Gavin Harper has assembled this
special supplement for us looking at hydrogen fuel and
fuel cells ...
The recent flurry of activity by the scientific and engineering
community has brought the fuel cell into the public eye, with
the subject being mentioned on the Green Building forum,
prompting a flurry of activity on the subject. We decided to
cover the topic with a round-up of some current projects,
interviews with people at the centre of the action, and an
exposition of the technology, with the aim of attempting to
answer some of the questions posed, and investigating
the real capabilities of this technology.
Many would believe that the fuel cell was a recent
innovation, however, its roots can be traced back to as
early as 1838. Sir William Robert Grove is widely heralded
as the father of the fuel cell. He was born in 1811, in
Swansea, Wales, a Welsh lawyer who later applied himself
to the mastery of science. He discovered what is known
as the Grove gas battery. In 1843 he published a diagram
and made a primitive model. However, it was not really
until much later (in 1959), that a fuel cell with a sizable
power output (5kW) was developed by British engineer,
Francis Thomas Bacon.
Green Building magazine :
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What is a fuel cell?A fuel cell is an electrochemical energy conversion device. Why
electrochemical? Because it harnesses the energy made in
chemical reactions to produce electrical energy. You might like
to think of a fuel cell as being very similar to a battery, however,
there are some key differences. A battery is a sealed unit, where
in the case of disposable batteries, once all of the reactants are
used up, their energy is depleted. Fuel cells differ in this respect,
in that the reactants are continuously replenished allowing the
cell to operate for much longer periods.
There is also another key difference. In a battery, because of
the chemical reactions that are occurring, the electrodes change
over the life of the battery. In the case of rechargeable batteries,
this change is reversible adding energy to the battery allows
the electrodes to change back into their original state. Fuel cells
differ significantly in this respect. A fuel cells electrodes are
catalytic and do not change considerably over the life of the fuel
cell. The fuel in a fuel cell is not burned, like in an engine, as such.
Fuel cells are quiet, even silent in operation, and are free from
polluting emissions. The key fuel in a fuel cell is hydrogen. Inmany fuel cells this is supplied as a gas, however, with some fuel
cells, for example direct methanol fuel cells, another fuel is used
which is a hydrogen carrier. This is to say, the methanol acts
as a transport mechanism for getting hydrogen to the fuel cell.
In Woking, natural gas is being used as a carrier for hydrogen,
being reformed on-site before it enters the fuel cell.
Why not just use hydrogen? Well, sometimes by using a
hydrogen carrier we make the fuel easier to transport and store.
These hydrogen carriers could have an important part to play
in a transition to a hydrogen economy, as they would allow us
to use existing infrastructure that is currently used to transport
petrol and other liquid fuels. However, it must also be noted
that there are carbon dioxide emissions as a result of using ahydrogen carrier.
The idea was broached on the Green Building Forum, of
a hydrogen infrastructure being a useless duplication of
infrastructure that is already present for distributing energy
namely our gas and electricity networks. However, if the idea
of hydrogen flowing through pipes in the street seems an alien
one, think back to before the discovery of North Sea gas, when
town gas contained up to 50% hydrogen. Allan Jones remains
confident that gas will continue to flow into the UK for many
years yet, citing that LPG is easily transportable and can be
imported easily. However, the UK has already changed from one
piped gas to another variety with different characteristics its
not inconceivable could happen again.
How do fuel cells work?Lets take a look at what happens inside a fuel cell. In this
example we are going to look at a proton exchange membrane
or polymer electrolyte membrane fuel cell. As we will see later,
there are different types of fuel cells, all of which follow similar
principles.
There are two sides to the fuel cell (see Figure 1), the anode
and the cathode. The anode is what we would call our positive
terminal or +V and the cathode, we would call our negative
terminal or -V. Our anode is perpetually exposed to hydrogen
which is constantly replenished from a supply such as a tank. The
cathode is perpetually exposed to oxygen, which is constantly
replenished. The two are separated by a plastic membrane made
from nafion, but more about that later.
Looking at the anode, the hydrogen must first diffuse through
a gas diffusion electrode (GDE). This is a material which allowsthe gas to pass through to the catalyst, whilst also conducting
electricity. Carbon cloths and papers are commonly used as they
have the property of being porous to the hydrogen, whilst also
conducting electricity.
Once it has passed through the GDE it comes into contact
with the catalyst, which generally contains platinum. The catalyst
facilitates the chemical reaction which comes next, allowing the
hydrogen to break into protons and electrons. The nafion plastic
membrane is porous to protons and allows them to pass through.
However, the electrons cannot pass through the membrane.
Instead, they take the next easiest route to reach the other side
this is the electric circuit that allows us to extract useful power
from the fuel cell. As the electrons travel round the circuit,
they do some work; this could be powering a motor in a car or
scooter, powering a portable electronic device or illuminating a
lamp in your home. When they reach the other side, the oxygen
(which can either be pure oxygen or the oxygen present in air)
reacts with the electrons which have travelled through the circuit,
and the protons which have travelled through the membrane, to
form water.
How much power does a fuel cell produce?Typically, each cell produces a potential difference of around 0.8
volts. In a similar way to in a car battery where multiple cells
Figure 1. Simplified diagram of how a fuel cell works.
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are used to create 12v, or in many electrical appliances where
we use a number of batteries to create a higher voltage, so
fuel cells can be built up in stacks. A fuel cell stack produces a
higher voltage than an individual fuel cell. The amount of current
that a fuel cell produces is largely dependent upon the size of
the active area where the chemical reaction is taking place.
Fuel cell effi cienc yOne of the great advantages of fuel cells is that unlike
conventional heat engines, such as the internal combustion
engine (the sort you find in your car or generator), or external
combustion engines (such as steam and Stirling engines), the
fuel cell is not constrained by the Carnot cycle effi ciency (that
is to say the rule of thermodynamics which govern the effi ciency
of conventional engines) because the fuel cells do not operate
using a thermal cycle. As a result, fuel cells are theoretically far
more effi cient than heat engines which results in extracting
more energy from our fuel. However, work is still in progress to
reach those theoretically attainable effi ciencies. From practical
experience effi ciencies of 30% are being attained which
correlates with those figures obtained by Paul in Montreal fromWikipedia on the Green Building Forum. Indeed, further to Pauls
comments about energy storage in batteries, projects like HARI
(see page 64), show how both technologies can be successfully
integrated providing effi cient short term storage, with the
capacity for longer-term storage of energy in hydrogen and
the ability to transport this energy easily or use it as a transport
fuel.
The hydrogen economyWith peak oil, and the possibility of peak coal, peak gas and peak
uranium, people are looking for new solutions to meet our energy
needs. The hydrogen economy is one proposed way of meeting
our energy needs more sustainably.
It is important to note, that hydrogen is not used as a
fuel but as a carrier for energy that is produced using other
means. Hydrogen is a near ideal energy carrier and permits a
decentralised energy infrastructure supporting the argument
for small scale, local energy production. It can also fit within
the framework of our present large scale energy generation
infrastructure and the ability to store it eliminates many of
the intermittency problems that are often discussed about
renewables.
Hydrogen is the first element on the periodic table for a very
special reason. It is the simplest of all chemicals, and also the
lightest. We do not need to fear running out of hydrogen, as
it is the most abundant element in the universe. Hydrogen is
a fantastic energy carrier and to understand what makes it so
good, you need to look at why carbon based energy carriers are
so bad. When a carbon based fuel burns, it produces carbon
dioxide, a greenhouse gas. In addition, when carbon is burned
in an internal combustion engine, impurities in the fuel lead
to sulphurous emissions that lead to acid rain, and the large
nitrogen content of the air, coupled with the high temperatures
reached inside the engine, promote the production of NOX.
Furthermore, engines also emit large amounts of unburnt
hydrocarbons, VOCs and masses of particulates. The damage
caused by burning carbon based fuels can clearly be seen in
places like Los Angeles, which is permanently shrouded in a
photochemical smog.
We have seen the evil of carbon based fuels, which are
responsible for the UKs transition to fuels with a lower carbon
content typified by the dash for gas, where coal was usurped
by natural gas as the energy of choice. However, the hydrogen
economy promises a future without carbon.
Hydrogen is colourless, odourless and tasteless, non toxic, an
produces water as its only by-product. However, it is dangerous
if mixed with air or oxygen because of the fire and explosion
risk. In principle, it can asphyxiate through denying the body
access to oxygen. Contrast this to carbon based fuels which
are also explosive, cause damage to the ecosystem, personal
health problems, and potential future fuel insecurity. Our global
prosperity in the past couple of centuries has been built on
carbon. Unfortunately carbon fuels have been burnt with little
consideration for future supply, and the damage done to the
environment. After much development, our carbon based
engines still only reach around 20% effi ciency. Furthermore,
our energy is currently generated centrally, which, due to lossesin transmission and conversion, can be horribly ineffi cient. By
transitioning to a hydrogen economy, the future is open for
distributed generation.
Types of fuel cellThere are a large number of fuel cell types in research and
development by a large number of companies. At the moment,
the state of fuel cell technology can be broken down into a
distinct number of types, all with their own distinct characteris-
tics, which make them ideal for certain applications.
So how is hydrogen made?There are a number of ways that we can get our hydrogen. It is
bit of a myth that hydrogen is a fuel. It isnt really, as there is nosuch thing as a hydrogen mine.
ElectrolysisAt school, you might have used a Hoffman apparatus in science
class. A Hoffman apparatus has a reservoir of water through
which is passed an electric current. The electric current
disassociates the hydrogen from the oxygen in the water. The
gas bubbles off from the electrodes and is collected in separate
storage containers. It is observed that twice as much hydrogen
is produced as oxygen. Taking a little bit of time to think about
this, we see that the chemical formula for water is H2O. This
makes sense as we can see that there is twice as much hydroge
in water as oxygen. The hydrogen produced by the electrolysis
process is very pure. Some fuel cells require a very pure form o
hydrogen so this is ideal.
The one disadvantage of electrolysis is that significant
amounts of electrical energy are needed for the process. Whilst
this electricity can be generated using clean, green renewable
energy, there are also many champions of a nuclear-hydrogen
economy using supposedly cheap nuclear energy to produce
hydrogen this would leave us with a toxic legacy of waste and
would negate many of the benefits of a clean hydrogen econom
Steam reformationBy combining high temperature steam, and methane, it is
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possible to extract hydrogen from this fossil fuel. The process
is fairly cheap and inexpensive, and the heat produced can also
be harnessed (known as co-generation which is covered later).
Co-generation provides us with lots of low-level heat which could
prove useful in local combined heat and power schemes. This
method does show a lot of promise as it is currently an effi cient
cheap technology that will work with existing gas-distribution
infrastructure. However the carbon emissions are impossible to
ignore.
Biomass gasification and reformationBiomass has proven itself as a relatively clean, near carbon
neutral source of energy. Agricultural waste, organic matter,
wood and other sources of biomass can be heated in a controlled
atmosphere without the presence of oxygen. This yields a gas
synthesis gas, which is hydrogen rich as well as containing
carbon monoxide and dioxide.
The carbon emissions from this source of energy are
effectively neutral as the carbon dioxide was taken out of the
atmosphere in the first place by the growing plants. However,carbon emissions in the production and distribution of Biomass
cannot be ignored. There is also the possibility of sequestering
the carbon produced in the gasification process. This could
effectively make biomass with hydrogen extraction a carbon
negative fuel.
PhotoelectrolysisPhotoelectrolysis is a relatively new unproven technology. It
involves using solar energy to stimulate a silicon junction similar
to a photovoltaic cell, with the distinction that instead of the
energy being converted to electricity, the silicon junction acts
directly on the water where electrolysis occurs. This technology
shows promise, although much development must be done.
Biologically produced hydrogenThere are a number of types of algae that use
photosynthesis to convert solar energy into hydrogen.
At the moment these processes have only been
demonstrated on a small scale, but research in this area
is intense. It is expected that great strides forward in
this area could be made.
Clean coal?There are vast tracts of coal throughout the world.
However, coal is carbon rich burning it doesnt
help global warming, and mining leaves scars on the
landscape which can last for generations. There are,
however, schemes afoot to look at gasifying coal,
extracting the carbon, and sequestering it.
Co, tri and quad generationWhilst fuel cells are some way off achieving their
theoretical maximum effi ciency, the waste heat that
is produced can be utilised in heating and cooling
applications. Whilst some heat is still lost this is
inevitable the model of producing electricity using
decentralised fuel cells is far more attractive than the
present model of centralised generation. Allan Jones
explores how fuel cells have the potential to reduce
the amount of energy wasted as dumped heat, and
electrical losses designed into a centralised generation scheme
(see page 66).
Taking the example of fuel cell combined heat and power from
natural gas, it is seen in Figure 2 what supporting equipment is
necessary to interface the fundamental unit of the fuel cell to
the rest of the building services. Heat generated from the fuel
cell is sequestered in a thermal store until it is required. This
helps to balance supply and demand. For backup purposes, and
for when additional heat is required, a gas burner is provided to
supplement the heat from the fuel cell.
Because many solid-oxide fuel cells are sensitive to sulphur,
the sulphur must first be scrubbed from the gas to avoid
contaminating the fuel cell. There are plans afoot to develop
fuel cells which tolerate of sulphur. Companies such as TMI in
Cleveland, Ohio are developing fuel cells that may not require
this intermediate step and can also run from gases with high
sulphur content such as that produced by agricultural biogas
digesters. The gas must then be humidified waste heat from
the fuel cell is used to heat up water to provide humidification.This humidification helps with the next step, which is the steam-
reformation of natural gas into hydrogen and carbon dioxide. The
gas then passes through a heat exchanger where it is pre-heated
before going to the fuel cell, along with air, which is also pre-
heated. The hot exhaust from the fuel cell is used to provide heat
for the heat exchanger which produces the hot water, preheats
the gases being supplied to the fuel cell and heats the reformer.
The output from the fuel cell is direct current (DC) which
must then be rectified into alternating current (AC) and
synchronised with the phase and frequency of the grid into which
it is being fed. In Woking (see page 66) it can be seen how fuel
cells have been selected with power electronics that can work
in island mode and maintain the grid frequency in the event
Figure 2. A tri-generation fuel cell.
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of a main grid failure. This capability enables the private wire
network to operate independently in the event that the grid fails.
Additionally, controls will interface with the building management
system, to match the fuel cells operation to the buildings need
for heat and power.
This is accomplished by using the heat for useful applications
heating a building, or coupled with absorptive cooling to
meet a buildings cooling loads in the summer. In Woking,quadgeneration is being employed, which builds upon co-
generation and tri-generation, by providing electricity, steam, hot
water, and chilled water for cooling, all from a single fuel source
natural gas. A variable fraction of the heat-generated can be
diverted into absorptive cooling, enabling the fuel cell quad-gen
system to match closely the demand for heating and cooling.
Additionally, because the electricity is generated close to source,
electrical losses are reduced.
Things are beginning to happen apace. For instance, the
PURE Energy Centre has announced its collaboration with Fuel
Cells Scotland (see page 62), to produce the first unplugged
hydrogen houses. The technology is in place, so it is only a
matter of time before the first commercially available domestic
fuel cell systems are being sold for early adopters. At last years
Grove Fuel Cell Symposium, the boiler manufacturer BAXI was
exhibiting a combined heat and power unit, so its only a matter
of time before smaller units become available.
Gavin Harper
Useful links:
WWW.GROVEFUELCELL.COM
WWW.LSHC.CO.UK
HTTP:// EC.EUROPA.EU/NEWS/SCIENCE/071011 _ 1 _ EN.HTM
Figure 3. Where the energy from tri-generation goes.
HYDROGENFUELTECHNOLOGY
For many years, hydrogen fuel cell technology has
been just over the horizon, just a couple of years
away, a little out of grasp. Its a technology that
doesnt ever seem to be covered in much depth in
the mainstream, as it is always seen as intangible
- something which is more science-fiction than science
fact, and something that we wont need to worry
about for a good couple of years yet...
The signs are this perception is rapidly changing.
A number of announcements and events in the past
couple of months have been the catalyst for hydrogen
technologies gaining increased prominence in the
media, and a number of announcements have shown
that hydrogen is beginning to permeate the publics
imagination. It is a technology which we can no longer
afford to ignore, as the signs are it is coming of age.
Whilst the buildings and installations that presently
feature fuel cells are few and far between, there
are signs in the air that the technology is gaining
momentum, and likely to become an increasingly
common sight in the next couple of years.
The bi-annual Grove Fuel Cell Symposium was held
in London recently, widely regarded as the worlds
premier fuel cell event, occupying the Queen Elizabeth
II conference centre for three days. The event acted
as a magnet for hydrogen experts, companies and
organisations to descend on London for a few
days and with any major event like this, there is
bound to be an intensification of press releases,announcements and interest in the field. BAXI, the
mainstream boiler manufacturer, were exhibiting a
fuel cell combined heat and power (CHP) system, that
could eventually scale down for smaller buildings, even
domestic use.
Support for hydrogen has just been bolstered by
the European Union, who believe that hydrogen is
part of the package in a sustainable energy future,
and so on the 11th of October 2007, they launched a
joint technology initiative, with over 1 billion funding
including 470m from the EU coffers. This is bound
to stimulate new research, innovative early-adopter
buildings which integrate fuel cell technology and
further development of the field.
All the signs point to exciting times ahead, and we
are seeing the first batch of designers integrating
hydrogen into their homes.
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PURE hydrogenOn the northernmost inhabited island of the
British Isles is an unlikely combination of cuttingedge energy technology, and an unrivalled pool of
expertise in hydrogen and fuel cells. Gavin Harper
visits the PURE Energy Centre and talks to Ross Gazey.
The Shetlands is too distant to be part of the national
grid, so the bulk of its power is produced by an ageing
oil-fired power station on the island. There are moves to
increase the amount of energy supplied to the island by
wind turbines and with the best wind resource in Europe,
there is certainly potential to meet the needs of its 20,000
inhabitants.
Unfortunately, the island is also one of contrasts.
Despite being the location of the North Sea oil industrys
massive transhipment terminal at Sullum Voe, the island
has the highest fuel prices in the United Kingdom because
the oil must be shipped back to the UK for refining, before
being shipped back for resale. This means that over 50%
of islanders spend over 20% of their income on fuel.
The lack of opportunities for graduates on the island
prompted the community development organisation
The Unst Partnership to look at investing in fuel cell
technology as a way of putting Unst on the energy map,
retaining skills on the island and diversifying revenue
streams. It is clear that in a small community such as onUnst, no man is an island and the close links between
PURE, and the community in which it operates, have
benefits for everyone.
Gazey likens the problems facing qualified young
people in Unst to the brain drain facing Britain in the
past couple of decades, where highly qualified graduates
left the shores of blighty to the US. However, resourceful
Gazey was determined for the same fate not to befall his
home island. Looking for opportunities to develop clean
energy opportunities for the future, he was instrumental in
the founding days of what is known as the PURE Energy
Centre.
In addition to creating six full-time equivalent jobs
on the island, the centre has also created wealth for its
community, as a result of the visitors to the centre, who
stay, spend money on the island and use the services
and accommodation. Forget Live Earth, Unst was the
first place in the world to hold a rock concert fuelled on
renewable hydrogen!
In a technology marketplace which is changing rapidly,
and the state of the art develops day-by-day, PURE has
built itself a formidable reputation in the European fuel
cell industry in a relatively short time. As well as the
technology improving, PURE believes that the economics
of the technology are starting to make sense predicting
that fuel cells will decrease in price by up to 50% in the
next three years bringing the technology to a much
wider marketplace.
Energy centreThe PURE system is based on the premise that hydrogen
should be produced from renewable sources. Presently
this comes courtesy of a pair of 6kW Proven wind
turbines, with plans to upgrade to two 15kW turbines
when some design issues are rectified.
Being a remote island in the middle of the North
Sea, Unst receives more than its fair share of wind, so
the availability from the turbines is very good indeed
-averaging around 45-50%. Power from the turbines is
used to heat the building by modified electric heaters,
designed to utilise the supply from the wind turbines more
effi ciently, and spare excess power is diverted into the
electrolyser unit to produce hydrogen.
The electrolyser and associated elec-trickery are
housed inside the Hy-Pod. PURE has designed the
system to be modular, housing all of the technology inside
an easily transportable unit (see inset right). This opensup many opportunities for shipping the device and rolling
out this solution around the world. Policy makers are
beginning to sit up and notice, with many from the great
and the good of UK and EU parliaments visiting PURE
since its establishment.
The hydrogen produced by the electrolyser is then
stored for later use in standard K type cylinders. This
is a cost-effective solution, and avoids the problems of
ineffi ciency and energy-loss associated with having to
compress the gas. PURE is able to do this because of its
novel electrolyser arrangement, which operates at system
pressure. The organisation then has a number of options.
It can use the hydrogen in a 5kW Plug Power fuel cellwhich provides electricity on-site, mounted next to the
HyPod. It has also been developing hydrogen cooking
appliances, the first iteration being the PURE hydrogen
barbecue, which often comes out for course attendees
if the weather is fine. In addition, PURE is developing an
internal combustion engine which will run on hydrogen
allowing cheap, legacy technology to reap the benefits of
clean hydrogen gas. The HyPod has also been equipped
to recharge the hydride cylinders inside the PURE
hydrogen vehicle, which Dr Daniel Aklil HAlluin commutes
to work in!
Hydrogen vehicleGazey told me that this is the first road-legal type-
approved hydrogen vehicle in the UK. There is a hint of
irony in its location, Gazey intimates, as on Unst, vehicles
do not require an MOT!
Whilst on many of the cars on the island, the tell-tale
signs of bubbling paint betray the secrets of the tin-
worm beneath, the ravages of the Shetland weather, and
high salt content of the atmosphere do not show on the
bodywork of Gazeys car, which he tells me, is ABS plastic
covered with a green film - proudly alluding to the cars
eco-credentials.
Gazey is clear to differentiate the PURE vehicle from
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the crowd -the PURE hydrogen car is refueled with 100%
green hydrogen. Many hydrogen vehicles are fuelled from
hydrogen produced from fossil fuel. His vehicle employs PEM
(proton exchange membrane) fuel cell technology to convert
hydrogen into electrical energy, which can power the cars
4.6kW DC electric motor. In the PURE car the hydrogen acts
in symphony with the lead-acid batteries originally fitted to
the G-Wiz car on which the PURE car was based, providing a
hydrogen hybrid solution and giving the car extra range and
acceleration.
I am told that one of the challenges with hydrogen vehicle
technology is designing a method for refueling, Gazey notes
that the PURE system works at a relatively low pressure.
However, he is quick to add that it does take six hours to fill
the cars metal hydride cylinder (a kind of can filled with a
hydrogen sponge which soaks up the gas). This is because
the vehicle is refueled at low-pressure, which helps to
circumvent some of the safety legislation that the mainstream
car manufacturers are having to grapple with. It is clear from
Gazeys description of the vehicle and refueling station that
he has a passion for flair and innovation.
So why Unst as the location for this novel enterprise?
In addition to creating a novel and innovative vehicle,very much in keeping with the current zeitgeist for green
technology sweeping the motoring industry, PURE has also
created the sustainable infrastructure to allow refuelling of
the hydrogen vehicle. All of this is surprising from one of
Britains remotest islands.
Road testI took the hydrogen car out for a spin and driving it was a
surreal experience. It became apparent that once inside,
anyone expecting more than a modicum of knee-room, was
likely to be severely distressed. As my large frame climbed
into the drivers seat, and flicked the red-switch retro-fitted
by PURE, the Ballard fuel cell whirred into action behind me.
The quiet hum of the cooling fans was a far cry from the roarof an internal combustion engine, and more akin to an engine
fan fitted to many cars.
Gazey reminded me that as the vehicle is gearless, there
are only two pedals, loud and soft, with no clutch to worry
about. To the right hand side of the steering wheel is a
chunky rotary knob. R, N, E and F denote reverse, neutral,
economy and fast. Ever the daredevil, I was urged to
plump for fast. Gingerly pushing on the accelerator, the car
surges forward. In all frankness, this was unexpected. Initial
acceleration is quite brisk. Turning out of the car park the
vehicles limitations become apparent as we disconcertingly
lurch to the left but Gazey reassured me that with several
hundred kilo of lead acid batteries and steel frame beneath
us were not going to roll over. On the straight the pedal
touches the floor, and the vehicle begins to get up to speed...
surprisingly nippy!
I was left with the feeling that it is amazing how such a
bold technical achievement has been accomplished by such a
small organisation and doubtless with pressure from declining
oil reserves, vehicles like the PURE are likely to become a
common sight on our streets in years to come.
Gavin Harper
For further info: PURE Energy Centre, Hagdale Industrial Estate,Unst, Shetland, ZE2 9DS
TECHSPECOFTHEPUREHYDROGENPROPELLEDCA
Vehicle body: 2 Door
Dimensions: L 2.6m, W 1.3m, H 1.6m
Rolling weight: 665kg
Turning circle: 3.5 metres
Top speed: 45mph/72kph
Tyres: 13 low rolling resistance
Drive: Rear-wheel drive
Power: 8x6v lead acid batteries and a
Ballard Nexa 1.2kW fuel cell
Motor: 4.6kW, 48V DC motor
Torque 50 lb ft @ 2000rpm
Fuel cell: Proton exchange membrane
Hydrogen storage: Metal hydride tanks
Braking: Hydraulic regenerative
Insurance group: 1
The PURE hydrogen car being refuelled and (inset) one of the hydrogen fuestations that are dotted across the island.
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Gavin Harper talks to Rupert Gammon,
system architect of the Hydrogen
and Renewables Integration Project
(HARI) at West Beacon Farm in
Leicestershire, the home of Tony
Marmont.
Tony Marmont is a name that has become
synonymous with renewable energy in
the UK. His West Beacon Farm has
become one of the great examples of
how renewable energies can integratewith the rural home.The hydrogen and
renewables integration project at his farm,
takes Tony Marmonts existing renewable
energy infrastructure and examines how
renewables could potentially integrate with
hydrogen infrastructure in the future.
The existing system consisted of a
mixed basket of renewables, including two
25kW Carter wind turbines a total installed
capacity of 13kWp of photovoltaics and
two micro-hydroelectric turbines with a
combined output in the region of 3kW.
The houses central heating needs aremet by a 10kW thermal heat pump,
circulating water from a coil at the bottom
of an artificial lake and a 15kW electrical,
38kW thermal Totem combined heat and
power unit that currently runs on liquified
petroleum gas, as well as an array of
evacuated tube solar thermal collectors
for hot water.
However, there is still work to be done.
Speaking to Dr Gammon of Bryte Energy
who has been responsible for much of
the design and implementation of the
project, there are still un-resolved issues
with the architecture of the systems
power electronics and it is constantly
evolving. For instance, the system has now
transitioned from a high voltage (600V)
bus concept shown in the system diagram
(right), to a lower voltage of 120V for the
main distribution system.
Batteries are used to provide short-
term energy storage. The team did
some experimentation with advanced
batteries, however, these have now been
disconnected in favour of traditional
lead-acid batteries which have proven to
be a more robust solution and a simpler
technology.
The most recent refinement to the
system takes the renewable electricity
produced by the solar arrays, micro hydro
turbines and wind turbines, and converts
any overcapacity that the batteries
cannot store into hydrogen. It does this
by electrolysis feeding spare power
into a 36kW electrolyser, which, in turn,
produces hydrogen at 25 bar which is
then compressed and stored in cylinders,
providing a measure of long-term energy
storage, which complements the shorter
term storage capability of the lead acidbatteries.
So now when additional power is
required on dull and windless days, a Plug
Power 5kW fuel cell takes the hydrogen
and turns it into electricity to augment
any power being produced from the
renewables. Interestingly, the stored
hydrogen can also be used to meet some
of the on-site transport energy needs.
More on that later.
Much has been learnt about the
practical implementation of hydrogentechnologies, and incremental
improvements have been made during the
life of the installation. Pipework has been
insulated over time to reduce thermal
losses, with plans to further insulate
the electrolyser. Furthermore, a water-
conservation strategy has been adopted,
whereby water, generated as a waste
product from the fuel cell, is recirculated
back to the electrolyser for production of
fresh hydrogen ensuring it is not wasted.
There has also been extensive research
and work needed to enable the integration
of the 5kW Plug Power fuel cell with
the other renewable power system.
Regardless of the hurdles Gammon
remains confident that the technology
underpinning the fuel cell concept is
fundamentally reliable and sound. Most
of the problems have been more as
a result of system integration. For
example, after experiencing problems with
controlling the fuel cell, it was decided to
move the fuel cell closer to the control
electronics, as the line was experiencing
some attenuation. There have also been
a few teething troubles and modifications
needed to the software controlling thefuel cell. Dr Gammon is clear, that whilst
the basic technology is sound, the jury is
still out on the full capabilities of the fuel
cell.
A significant amount of energy is
produced by the installation at Beacon
Farm. According to Tony Marmont, the
energy generated on-site since the mid-
eighties averages 50MWh per annum.
Before the HARI project, 30MWh, on
average, was used on site each year and
the surplus 20MWh was exported to the
grid. Now the spare capacity is divertedinto hydrogen production, however,
whenever energy is converted from one
form to another, some is invariably lost
as heat. Tony Marmont estimates that
the round-trip effi ciency of converting
Hydrogen integrationat West Beacon Farm
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electricity to hydrogen, then back toelectricity, is around 30% - with 70% being
lost as a result of ineffi ciency.
Since the system has been operational,
3.6MWh equivalent of hydrogen has
been generated and stored onsite, whilst
around 6MWh was lost as leaks during the
bedding in process, but this issue is now
resolved. This resulted in West Beacon
Farm temporarily being a net importer of
green energy. However, in the future, the
plan is for the farm to be able to operate
independently, with no need to buy from
or sell to the grid.
From storage to transportOriginally, there were plans to develop a
fuel cell range extender for an electric car.
However, these plans have been shelved
in favour of developing a dual-fuel (petrol
and hydrogen) car.
Whilst internal combustion engines are
not the most effi cient technology, they
are very well understood, and this feature
has made them appealing for the first
wave of hydrogen vehicle development.
Indeed, BMW has decided to stick with
internal combustion engine technology
for its Hydrogen 7. The plans are to
employ compressed hydrogen stored in
a pressurised tank the simplest option
for storing the hydrogen. There are other
methods under exploration
Plans are afoot at the farm to modify
a Toyota Prius to work as a dual fuel
vehicle. Asking why it was decided to keep
the legacy option of petrol, Gammonreplies dual fuel never gets stranded
anywhere. If anything, this highlights
how the infrastructure needed to support
hydrogen transportation will need to be
developed significantly for the technology
to become a practical option for the
average motorist.
Lessons learntThe work conducted to date is showing
that whilst there is a need for continued
investment and development, practical
hydrogen-based solutions are not too far
away. Asking about the lessons learnedfrom the project, Gammon replies: The
project has certainly shown us lots of
small problems, but the big picture is that
it has helped us to understand how the
concept of a hydrogen economy really
will work and it strongly underlines the
fact that it is not about electricity storage,
there are other ways of doing that but
its about hydrogen as a grid balancing
mechanism which also produces transport
fuel. Its not about storage, its about
transferring surplus electricity to use as a
transport fuel.
Gavin HarperFurther Information:
WWW.BEACONENERGY.CO.UK/PDFS/WESTBEACON-
FARM _ 050208.PDF
Gammon, R., Roy, A., Barton, J. & Little, M.,(2006) Hydrogen and Renewables Integration,CREST, Loughborough UniversityWWW.BRYTE-ENERGY.COM
All images and table courtesy of Dr RupertGammon
Table 1. Summary of all renewable energy systems at West Beacon Farm.
System Manufacturer/Supplier/ Model Designation Rated Performance Cost (in )(indicative)
Electrolyser Hydrogenics (formerly Vandenborre) 8 Nm 3/hour of H2, 34kW, 2.5 MPa (25 bar) rated 143,000
Fuel cell (1) Intelligent Energy, CHP Unit 2 kW (el), 2kW (th), 24 VDC 25,000
Fuel cell (2) Plug Power GenCore, supplied by SiGen Ltd 5 kW (el), 48 V DC 20,000
H2 Compressor Hydro-Pac supplied by BOC 11 Nm3
/hour, 3.75 kW, 8:1 compression ratio 59,000H
2Storage Supplied by BOC 48 cylinders, each 0.475 m3, 13.7MPa (137 bar) max pressure,
2856 Nm3 total H2
capacity122,000
Sub total cost o f fuel ce ll system 369,000
Wind turbines Carter wind turbines 2 x 25kW two bladed stall-regulated, pitch over-speed 50,000
Solar PV BP 13kW total, mixed polycrystalline and monocrystalline 60,000
Hydro-electric Two systems installed by Dulas 850W cross-flow turbine with 2m head2.2kW Turgo turbine with 25m head
67,000
Integrationsystem
Control techniques and bespoke convertersfrom Loughborough University
Various 49,000
All systems total cost 595,000
West Beacon Farm hydrogen project:above: the house behind the hydrogen shedbelow left : the electrolyser that makes hydrogeexcess renewable energybelow right: the Plug Power fuel cell
bottom: the hydrogen storage tanks.
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an interview with Allan Jones
Allan Jones, MBE was the mastermind behind the UKs first
fuel cell CHP venture in Woking, and is now Chief Executive
Offi cer of the London Climate Change Agency. Gavin Harper
talked to Jones about fuel cells and private wire networks,
and about their future role in our built environment...
Ibegan by asking Jones why he had embarked on the idea of
combining fuel cell technology with private wire (local supply)
networks. Was it more for technical or regulatory reasons,
and what advantages did such networks have over the national
grid? The fuel cell CHP was embedded into an existing private
wire network at Woking Park and the fuel cell CHP was used
as a black start generator (as well as a CHP) to enable the
decentralised energy system at Woking Park to operate in island
generation mode in the event of a failure of the national grid.
This enabled the three swimming pools and the leisure centre to
continue in operation whilst everywhere else around them could
be in darkness. Island generation is a key attribute of fuel cell
CHP since they can switch from grid connect to island operation
in 0.5 milli seconds. Although Woking has other island generation
systems, this is very fast. For example, computers crash without
power supply at 8 milli seconds so would not even see a power
cut with a fuel cell driven island generation system. This is why
big banks and credit card companies use fuel cells in the USA.
The Woking Park system actually operated in island generation
mode due to power cuts in the national grid several times whilst
I was at Woking. The Woking Park decentralised energy system
comprises other larger CHP trigeneration systems and solar
photovoltaics. The heat from the fuel cell CHP was used for
supplying into both the district heating and cooling (via heat fired
absorption chillers) systems.
Electricity, heat and cooling was required for the Woking
Park site and supplying electricity on private wire networks atretail (though competitive) prices dramatically increased the
economics of the project by 400% over supplying electricity into
the national grid at very low wholesale prices. The decentralised
energy system at Woking Park met all of the electricity, heat and
cooling requirements of the site as well as being a net exporter
of surplus power which was supplied to other Woking sites at
competitive retail prices under the exempt licensing regime in
the UK, paying only a distribution charge to the local public wires
distribution network operator, ie., no grid transmission charges,
losses or government levies.
There were financial benefits because of the economics of
operating private wire networks under the exempt licensing
regime. I implemented 80 (yes eighty) decentralised energysystems on private wire networks at Woking, which not only
supplied these individual sites but also traded their electricity
together (imports/exports) between sites over the local public
wires distribution network without the need to sell or buy
electricity from the national grid.
I then asked whether he was disappointed with the current
regulatory framework for UK energy supplies, and what he
would change? The current regulatory framework does not
really inhibit supply on private wire networks to non domestic
customers since up to 100MW can be generated, distributed
and supplied on each private wire network. However, this is
limited to only 1MW for domestic customers on each private wire
What are ...?
Private wire networks are a network of supply wires within anorganisations buildings for distributing electricity aroundthe organisation.
Public wire networks are a network of wires linking differentbuildings and organisations. This includes the national grid.
Working towards a hydrogen future
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network with the export over public wires limited to 2.5MW in
aggregate. This is unfair on domestic customers, since cheaper
electricity can be supplied to domestic customers on private wire
networks than from the grid, and inhibits the ability to provide
decentralised energy to mixed development, which in London is
very large scale, whereas in Woking they never came up against
this barrier. In its Energy White Paper the government promised
to look into the regulatory barriers to decentralised energy.
So based on that, how do you believe our energy markets
might adapt to a future hydrogen economy and how might the
current regulatory framework change or adapt? The current
regulatory framework only really applies to electricity and gas.
It does not concern itself with heat, heat to cool, renewable
gases and liquid fuels (both rich in hydrogen) or hydrogen.
However, if the regulatory barriers to decentralised energy are
removed, this would have the effect of not only stimulating low
and zero carbon technologies and infrastructure, it would also
provide an accelerated pathway to renewable hydrogen. For
example, renewable gases and liquid fuels derived from waste
and biomass (largest renewable energy resource in London) can
provide todays renewable energy for buildings (via CHP) and
transport, and tomorrows renewable hydrogen for buildings (via
CHP) and transport, since biogas (derived from organic waste
and biomass, via anaerobic digestion) and syngas (town gas) and
synthetic liquid fuels (derived from non organic or mixed waste
via gasification or pyrolysis) are all hydrogen rich fuels.
But to what extent do you believe that fuel cells can act as
an enabling technology for decentralised energy? Fuel cells
will not act as an enabling technology for decentralised energy
but decentralised energy will act as enabling technology for
fuel cells since the value of electricity would be increased which
would significantly improve the economics of fuel cells and bring
forward the utilisation of fuel cells.
So what give you the most hope for the future? Londontaking the lead in tackling climate change on a world city-wide
stage and the London Climate Change Agencys role in that.
Which leads us on to the gargantuan challenge Jones current
faces as Chief Executive Offi cer of the London Climate Change
Agency (LCCA), a post which he has now held since 2004. The
LCCA is the Mayors direct-delivery agency which has already se
in motion projects, including carbon accounting, Better Buildings
Partnership a project to enable and accelerate the uptake of
energy effi ciency retrofits in Londons commercial offi ces under
the Green Organisations Programme, study on the implications
for CO2
emissions of housing growth in London and prototyping
a deep service model for domestic energy effi ciency and micro
generation, which is now being rolled out under the Green HomeProgramme, renewable energy projects at the London Transpor
Museum, Palestra and City Hall, fuel cell CHP trigeneration study
at Palestra (which is currently being procured), renewable gases
and liquid fuels from waste and biomass project currently under
way with London Remade and the London ESCO a joint ventur
Energy Services Company with EDF Energy established to desig
finance, build and operate decentralised energy systems.
This is no small task, with urban centres such as London
possessing an extremely high energy density. London uses the
same amount of energy in a year as Greece or Portugal, so how
does Jones see us meeting this demand sustainably, and will
hydrogen help us in meeting this aim? The answer to this is
in the Mayors Climate Change Action Plan. 75% of Londons
CO2
emissions is due to centralised energy supply. This is not
normally shown in this way since emissions are normally smeare
across end use (ie., housing, commercial, industrial, etc). Howeve
it is important to identify the real cause of climate change since
this is how emissions can be reduced at large scale and quickly.
The Action Plan sets a target of taking 25% of Londons energy
supply of reliance on centralised energy by 2025 and by more
than 50% by 2050. This, taken together with energy effi ciency
and the greening up of the remnants of centralised energy
The now famous Woking combined heat and power plant with (inset) the fuelcell building set alongside the public swimmimg baths.
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with large scale renewables will achieve a 60% reduction in CO2
emissions, not by 2050, but by 2025. Hydrogen will play a role in
this.
During the dash for gas Britain transitioned a significant
chunk of its centralised energy generating capacity to natural
gas. The fuel cells being used in Woking and other projects,
reform hydrogen from natural gas. Some people hold concerns
that, in the future, this will make Britain dependent on other
countries for its energy. Jones was quick to allay fears about
natural gas supply. With the UKs natural gas supplies rapidly
dwindling, how does Jones see us moving beyond reformation
of natural gas for hydrogen, and if so how does he foresee us
producing hydrogen on the scale required? The UKs natural gas
supplies may be dwindling but the UK has taken action on this by
connecting Norwegian gas to the UK by pipeline and establishing
a liquefied natural gas (LNG) infrastructure in the UK. LNG has
a very high energy density so very large amounts of gas can be
transported in a very small space. The UK has established LNG
terminals in the UK (I used LNG in Woking), enabling LNG to be
transported by tanker from such places as Indonesia, Trinidad
and elsewhere. The UK does not actually use any Siberian gasand probably has no need to. Therefore, natural gas will be
around for some time yet and probably longer if it is used for
CHP and notCCGT (combined cycle gas turbine)power stations.
Therefore, hydrogen can continue to be reformed from natural
gas for sometime yet but London is working on a renewable
hydrogen energy infrastructure to replace the natural gas
infrastructure.
Jones clearly has a record of practical implementation of
fuel cell projects and could well be the most qualified person
in the UK to crystal ball gaze and see the road ahead for
hydrogen in the UK. I asked him to put his neck on the line and
give us some sort of timescale. Hydrogen is 75% of the known
universe so is in pretty much everything, including us. Hydrogenwill be transported by natural gas (initially), biogas, syngas or
synthetic liquid fuels (longer term). This will be supplemented
by electrolysing renewable electricity locally but I do not see
this as a major source. Other sources of hydrogen also have
potential, such as growing hydrogen from microbes or a direct
photosynthesis process. Therefore, hydrogen will be transported
as part of a fuel by pipeline (gases) or by tanker (liquids).
There is no need to transport pure hydrogen (which would be
expensive, if not impractical) since hydrogen is only needed at
the point of supply at the stationary or transport fuel cell where
it can be reformed in situ at the fuel cell CHP or filling station for
fuel cell transportation. This could be technically feasible by 2025
and politically feasible by the same date, if the regulatory barriers
to decentralised energy were removed.
The incumbent government appears to have a resurgent
interest in nuclear power after several decades and seems
poised to guide us into a nuclear future, whilst other voices,
such as Centre for Alternative Technologys ZeroCarbonBritain1
report, dissent from this view and see the UK becoming a
nuclear free nation. The hydrogen economy has voices on both
sides of the fence. Some see a hydrogen future enabled by
nuclear installations electrolysing water to produce hydrogen,
whilst others believe that hydrogen is the key to enabling
decentralised technologies. But how does Jones feel about the
view put forward by some promoters of a nuclear/hydrogen
future, and whether nuclear power has a role to play in his
vision of the hydrogen economy. No. Nuclear power stations
are very ineffi cient, quite apart from the very significant cost,
environmental, disposal, long term storage and political issues.
According to the Digest of UK Energy Statistics (DUKES)
published by BERR (formerly the DTI), nuclear power stations
are only 38% effi cient across the year as a whole. Two thirds of
its energy is wasted into the atmosphere through cooling towers
and losses in the grid and a further 9% of electricity is lost in the
grid transmission and distribution systems (Ofgem figures). This
wasted thermal and electrical energy has to be replaced by fossil
fuel energy to heat buildings, steam for industry and losses in
the grid. UK power stations use 50% of the UKs water resources
and in a declining water resource world, with climate change, this
is just not sustainable and not conducive to what we are looking
for in a renewable hydrogen energy economy.
Nuclear power stations and so called carbon capture and
sequestered coal fired power stations are bear traps. Generating
hydrogen from power stations using electrolysis is technically
feasible but not sustainable for the reasons as above, quiteapart from consuming even more water, as well as the expense
and impracticability of transporting hydrogen long distances
from power stations. In other words hydrogen goes with low and
zero carbon decentralised energy and not with unsustainable
centralised energy.
Ken Livingstone is quoted as saying, What Allan Jones has
achieved in Woking is nothing short of revolutionary and I
am delighted that he has agreed to take up the challenge of
replicating what he achieved in one borough on Londons world-
city sized stage.
I asked Jones how he planned to make London the green
capital of Europe and he commented that the plan, as set outin the Mayors Climate Change Action Plan, concerns tackling
emissions in 7 sectors:
l existing homes
l existing commercial and municipal activity
l new build and development
l energy supply
l ground transport
l aviation
l Mayoral Group showing by doing.
Of these, energy supply is by far the largest emitter, causing
emissions of 35 million tonnes pa, 75% of Londons emissions.
This is set to increase by 15% by 2025 if no action is taken.
In closing our interview, Jones says, The Mayors ambition is
not just for London to become the green capital of Europe but
for London to lead the fight against climate change on a world
stage. That is why the C40, bringing together 40 of the worlds
largest cities, and the partnership with the Clinton Foundation
has been established. 75% of the worlds CO2
emissions comes
from cities. Cities are most at risk from climate change and cities
are best placed to tackle climate change. Cities can do this and
do not need permission from federal governments to do so.
Gavin Harper
1. WWW.ZEROCARBONBRITAIN.COM
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THEATREISHYDROGENFUELCELLPOWERED
The Arcola Theatre is a good example of why Londons culturalsector is so dynamic and successful. Arcola is leading the theatreindustry in developing this premiere sustainable production and Iknow that many other theatres are now keen to follow. The Living
Unknown Soldier is unique in that it is the worlds first productionto be powered by a fuel cell, supplied and sponsored by the LondonHydrogen Partnership. Every individual, every business, every shop,and every theatre has a part to play in tackling climate changeand this lead by Arcola Theatre is just what we need said KenLivingstone, Mayor of London
Londons Arcola Theatre, one of the UKs leading independentvenues, has installed a hydrogen fuel cell to power its caf/bar andselected main house shows. The fuel cell operates almost silently,producing nothing but electricity and clean water. The 5kW fuel cellsystem takes pride of place in the foyer of the theatre, accompaniedby displays describing the benefits and challenges posed by thistechnology. The prominent location of the fuel cell, and the challengeof relying entirely upon it, provides both a powerful educational tooland a source of motivation for reducing energy use.
The first show to be powered by the fuel cell, The Living UnknownSoldier, produced by Strawberry Vale, may well be Londonspremier ecologically sustainable show. The environmental impactof all aspects of the production has been minimised, including setconstruction, marketing, company travel and show lighting. Theproductions environmental footprint will be evaluated by GlobalAction Plan and the lessons learned published for the benefit of otherpractitioners.
The lighting for the show has a peak power consumption of 4.5kW,up to 60% less than comparable lighting installations. This is madepossible through extensive use of LED lighting and the careful use ofhigh effi ciency tungsten lamps.
In addition Arcolas bar/caf has been upgraded to an eco-bar,serving organic and fair-trade refreshments, illuminated by a low
energy LED lighting system. The lighting for the entire caf/bar nowconsumes under 500 watts, a saving of 60%, with the added benefitof providing near infinite flexibility in light level and colour forperfect daytime operation as well as for caf/bar performances.
This project is part of Arcola Theatres extensive sustainability-relatedactivities - under the banner of Arcola Energy. It is spearheaded byDr Ben Todd, the theatres executive director, who also works as aconsultant in the fuel cell industry. He said: The arts have a crucialrole to play in elucidating and motivating the changes in lifestylenecessary to deliver an equitable future for all humankind. ThroughArcola Energy, Arcola Theatre is demonstrating that bold changes canbe made and that making them offers exciting opportunities for newcreative partnerships.
Todd also noted that When we launched Arcola Energy in July 2007we planned to install renewable technologies within 12 months, thisis unlikely to be possible due to restrictions on what we can do asa leaseholder and the protracted business of securing the freeholdfor our premises a problem faced by many organisations. Theinstallation of the fuel cell and our present emphasis on greeningour operations are examples of what can be done now, whilstinfrastructure projects are under development.
WWW.ARCOLAENERGY.COM
HYDROGENHOMESFOR SCOTLAND
Hjaltland Housing Association, along with the PURE Energy Centreand Fuel Cells Scotland, is to build the UKs first hydrogen homes,unplugged from the grid, and storing power generated onsite in theform of hydrogen, which can then be converted to heat and energy b
a solid-oxide fuel cell, with combined electrical and thermal effi cienof 90%.
The houses are going to be powered by micro CHP fuel cell systemsdeveloped by Fuel Cells Scotland. Gavin Harper caught up with FuelCells Scotland at the H207 conference earlier this year in Aberdeenwhere they were exhibiting their novel solid-oxide fuel cell. By thetime it reached the conference, the demonstration model had beenoperating for 1500 hours. It was a first in that the cell is a uniqueseal-less design. By eliminating the seals from the fuel cells, thephysical dimensions can be shrunk, making a higher energy-densitycell, suitable for small applications like domestic micro-CHP. The fuecell solution will also offer some advantages over the Stirling enginebased micro-CHP units currently being installed in some homes, inthat they have no moving parts.
The fuel cells have been developed by Dr TG Lindsay of Fuel CellsScotland whose work on solid oxide fuel cell stacks is the culminatioof 12 years of research and development. The installation is beingsupported by the Scottish Executive Renewable Hydrogen and FuelCell Scheme, and the applications side will be managed by PUREEnergy Centre.
Once the fuel cell has been installed, the second phase of the scheminvolves developing a renewable-sourced hydrogen production andstorage infrastructure around the houses. Initially, the hydrogen wilbe used to meet the homes heat and power needs, but the projecthopes to eventually develop to the point of producing hydrogen forfuelling a pair of hydrogen cars for the houses.
These houses have the potential to be a blueprint for future zero-carbon housing, as with renewably-sourced hydrogen, the only outpfrom the fuel cells will be pure water. Whilst at the moment, thetechnology is expensive, and the project is made possible by grant-funding, as the technology develops its economic-competitiveness, icould provide a clean energy-lifeline for isolated communities.
Dr Daniel Aklil DHalluin of the PURE Energy Centre said, 40% ofthe worldwide population live with no access to electricity and heatThe CHP scheme will provide these populations with such access. Itwill also provide communities around the world with access to cleanhydrogen fuel to power clean vehicles.
Links:
WWW.PURE.SHETLAND.CO.UK/HTML/INDEX.HTML
WWW.HJALTLAND.ORG.UK
WWW.FUELCELLS-SCOTLAND.COM