Written Evidence from Francis John Golden
The above Inquiry is focusing on the cost, cleanliness,
efficiency and sustainability of existing energy sources in Wales.
In addition to consider the merits of newer forms of energy provision.
One source of energy that has not been exploited
at all in Wales and could be considered as a "newer form
of energy provision" is mswmunicipal solid waste.
*The calorific value of coal is 28Gj per
tonne, that of rdf: refuse-derived fuel (dried msw after metals,
minerals and hard plastics extracted for recycling) is about 20
Gj per tonne. By comparison oil is 46Gj per tonne and nearly all
plastic about 39Gj. LNG is about 40Gj per tonne.
*Environment AgencyEnergy content of materials.
The past custom of landfilling msw and plastic
is shewn as a considerable waste of what should be recoverable
energy from a sustainable source.
Recognising that recovery of this energy by
incineration is not welcome due to concern about emissions and
the intrinsic inefficiency of mass burning, several engineering
companies** developed more efficient and environmentally benign
thermal solutions, viz. pyrolysis and gasification.
**Of these only Compact Power and GEM, with UK patented
To encourage development of these the then Energy
Minister Mr Wilson in 2002 brought in the RO (Renewable Obligation)
adding that the UK had lost out on the engineering opportunities
offered by North Sea oil in the 1970s and did not want to make
this mistake again.
Apart from plant and forestry fuel that could
be incinerated, the RO was and is restricted to non-fossil fuel
derived waste converted by the Advanced Conversion Technological
processes of pyrolysis, gasification and anaerobic digestion.
It was therefore announced that processes creating energy from
non-fossil fuel derived waste utilising ACT (Advanced Conversion
Technology) would be entitled to a ROC (Renewable Obligation Certificate)
for every MW generated. Each would have an initial value of £30,
but would escalate each year to guarantee a return on capital
invested and establish a new, British industry.
MSW is a heterogeneous waste. Picking and mechanical
extraction processes can recover the cans, glass, plastic containers
and minerals, but no process can completely extract the remnants
of plastic film: that is still entrained in the residue.
To full entitlement to ROCs the UK Regulations
require that no more than 2% (of plastic) by calorific value can
be entrained. That is virtually impossible to achieve. That is
now being recognised by the DTI in the Renewable Obligation consultation
and consideration is being given to extending this to 10%. Ireland
appears to be going in this direction as well, but is giving thought
to having the entrained plastic be measured by weight rather than
The original initiative by the DTI has, to all
intents and purposes, failed to live up to expectations. The imposition
of the 2% "contamination" limit of MSW has in fact restricted
the RO (in respect of waste) to biomass only and done nothing
to divert waste away from the landfill.
The two companies remaining are:
Graveson Energy Management, ie GEM:
pyrolysis, ie air is excluded and the prepared fuel is "flash"
converted at about 820o. There is no need for a tall stack. Dioxins
and furans are not created.
Compact Power: pyrolysis, gasification
and incineration (to burn off the emissions).
All the other companies have ceased or dormant.
(There are other companies now in play, they
are claimed to be starved air, ie gasification, but are they little
more than incineration,?).
In three years there has been little progress.
Compact Power has recently been granted planning
consent for a 25,000 tonne demonstration plant at Bristol.
GEM has planning consent in a major poultry
firm in Norwich: a plant using chicken litter as fuel to generate
in the first phase 2/3 Mwh of electricity and the same in useable
heat, then in the second phase 10 to 12 Mwh plus the same in useable
heat. Also, enabled with a DEFRA grant, a demonstration plant
to treat 25,000 tonnes of prepared msw is likely at a site near
To date Compact Power received £3,000 in
state aid and spent £20 million and has an operating plant
at Avonmouth treating hospital waste.
Graveson Energy Management, GEM, Romsey has
had no state aid, but spent at least £8 million and a 1/3size
pilot plant operating at Romsey since 1999.
Handicaps to development are:
Procurement procedures for local
authorities not stipulating ACT.
Uncertainty about "new"
Banks require contract in place.
LAs will give this only if funds are in place, ergo, little movement
away from landfill.
Financial incentive of the ROC not
achieveable for the above reasons.
Major waste operators own landfills.
The application of the Waste Incineration
Directive to a pure pyrolysis process like GEM where there is
"incineration" only in the reciprocating engine powering
The 2004 DEFRA scheme to provide support funding
to ten applications involves incredible expense to the applicants
while changing the conditions so that any support funding will
not be for initial construct, when these companies really need
it, but rather to the running once its built. The awards already
given seem to have gone to the tried and tested rather than genuinely
innovative British technology.
GEM is intending to make a planning application
in Wales. The site in question has road and rail links. Prepared
msw, with mechanical pre-sorting and drying preferably at LA facilities
would be converted and 50,000tonnes would deliver eight to 11
Mwhe plus the same in useable heat to the grid. The ash, at about
10% could be incorporated into concrete blocks (similar to well
known thermolite blocks from main power stations) and nothing
going to landfill sites.
Once up and running it will make a significant
impact on the waste diversion and renewable energy scene. At that
stage then consideration could be given to stripping off the hydrogen
from the synthetic gas for research into road or other use.
In the Waste Strategy composting is frequently
the preferred option for green and non-fossil fuel derived waste.
The residue or fibre produced by these MBT, aerobic and anaerobic
patent processes is likely to be spread as cover on landfill.
There it decomposes and produces methane. One tonne of which is
equivalent to 20 tonnes of CO2. It is better to reduce these emissions
rather than increase them. The residue when dried down to about
5% moisture would be an excellent fuel for the GEM pyrolysis process.
So would the hospital plastic that is currently sterilised then
put to landfill.
Pyrolysis is the most efficient of the three
thermal technologies. If all the waste going to landfill in Wales
was prepared as fuel for GEM converters most of the energy problems
would have a solution. Accompanied by recycling, most of the landfill
diversion problems would be solved as well.
If each landfill or civic amenity
site had a waste fuel preparation and GEM power station connected,
that would provide a continuous rather than intermittent (wind)
source of green electricity. This would make the balancing needed
by the grid that much controllable and reliable.
2. More delegation to Wales could
ensure that Wales' Local Authorities be encouraged to direct that
waste be prepared for utilisation as a fuel for ACT.
3. The current portfolio has
no provision for ACT generated electricity. Ensuring that that
was included could make a major addition to the future portfolio.
29 November 2005