Alan Midwinter presentation 29 09 by 2zn5u0

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									        Biomethane Review of UK
                         activity

                              Alan Midwinter
Wardell Armstong LLP   SGN Project Manager
                        29th September 2011
 Who are SGN?

• Scotia Gas Networks –
  Formed in June 2005 following
  the acquisition of two gas
  distribution networks from
  National Grid (Scotland and
  South of England)

• Owns and operates the second
  largest gas distribution network
  in the UK.

• Serving over 5.8 million
  customers

                                     2
Why gas networks here?
 DECC 2050 Pathways Study
 Demonstrated that substantial electrification of heat and transport is
 required in order to meet 2050 Targets (80% GHG emission reduction)


 What is the future for the gas networks ?
 ENA Gas Futures Group commissioned Redpoint to develop future gas
 scenarios to 2050 and beyond :-

  •   Retaining gas infrastructure could be up to £700bn cheaper to UK plc
      than a complete electrification solution
  •   Require low carbon renewable gas (BIOGAS) for Bio-methane
  •   Potential for Bio-methane injection - 50% of UK domestic heating load


 DECC output targets for bio-methane are 7TWh p.a. by 2020
 and could extend to 150-210 TWh per annum of renewable
 gas by 2050                                                                  3
Gas Futures Redpoint
                          Pathways
                           involving
                          significant
                       Biomethane to
                       Grid Injection


                       •Green Gas
                       •Gas Versatility
‘Green Gas’ Incentive
Low Carbon Energy -
Biogas
•   UK produces 16 million tonnes of food waste (8 million tonnes from
    households) and 90 million tonnes of animal waste annually with the majority
    going to landfill.

•   Organic material degrades producing methane gas, 23 times more damaging
    to the environment as a greenhouse gas than carbon dioxide.

•   EU landfill directive obliges local authorities to send less biodegradable
    waste to landfill, generating requirement to recycle or reprocess.

•   Anaerobic Digestion (AD) is a waste treatment process for organic waste,
    recovering energy from waste in the form of biogas (50% to 65% methane)

•   Biogas traditionally has been used for Electricity generation but can be
    cleaned for Biomethane injection or used as CNG for vehicle fuel.


                                                                                   6
Government Incentives
•   UK Government is committed to meet Greenhouse Gas Emission targets
     •   15% reduction by 2020
     •   80% reduction by 2050

•   Landfill taxes – increasing to £80 per tonne.

     •   Energy recovery potential for AD could support 2,100 AD plants (50,000 t) will be required.

•   The Government has incentive schemes for the use of Biogas as a low carbon
    energy

     •   Existing incentives FIT’s & ROC’s for electricity generation
     •   RTFO’s for vehicle fuels

•   Government has now incentivised a scheme that will for the first time provide
    long-term guaranteed financial support for renewable heat installations

     •   Renewable Heat Incentive (RHI)
RHI & Bio-methane Injection

• Introduction of the RHI (July 2011) provides a sound economic
  pathway for gas injection into the grid, financially attractive above
  500 m3/h bio-gas (300 m3/h biomethane).

• Bio-methane RHI tariff is currently 6.8p / kWh

• 20 year tariff to include capital cost for all plant

• Degression of RHI tariff will feature once target volume is reached

• Bio-methane injection is 50% more efficient than electricity only
  applications

• Important contribution to a stable and reliable energy supply           8
Comparative Income




£/m




                                       9
         Biogas Plant Capacity m /hr
                                3
Didcot - The Objectives
Project time-line

• SGN commissioned Feasibility
  study in April 2009
• Project Approval April 2010
• 3 October 2010 SGN, working with
  our partners, Thames Water and
  Centrica, delivered the first Bio-
  methane gas to Grid in the UK




                                       11
 Key Objectives

• SGN used Innovation Funding to deliver a number of
  important objectives:
   •   Understand Legislative and Regulatory issues
   •   Improve understanding in relation into gas quality (Oxygen and
       siloxanes in particular)
   •   Understand the impacts of bio-methane on the operation and
       configuration of the local gas network
   •   Prove biogas clean-up and upgrading technology in the UK
   •   Provide a ‘base-line’ for gas quality monitoring and associated
       equipment from which lower cost options could be developed
   •   Share Project learning and improve efficiency to the benefit of future
       schemes



                                                                                12
Regulatory Requirements
• Safety (HSE)
   •   Transporters may only Transport gas that complies with
       provisions of Gas Safety Management Regulations (GS(M)R)
   •   Gas Transporters are obliged (by the Regulations) to take
       sufficient measures to confirm that gas is compliant or must
       not allow gas to flow
• Commercial (Ofgem and the Uniform Network Code)
   •   The bio-methane must have its energy measured in
       compliance with Gas Thermal Energy Regulations
   •   The processes must comply with appropriate UNC
       arrangements



                                                                      13
Gas Quality Baseline
• Establish Biogas composition and available flow-rate
• Ensure the local SGN Network could accept the
  volume of gas that will be produced on a 24/7 basis
• Establish biomethane gas quality requirement,
  specifically around :
   •   Oxygen
   •   Siloxanes
   •   Calorific value
• Identify appropriate biogas clean-up and upgrading
  technology for Didcot


                                                         14
Key Objective Outputs
• Oxygen content could potentially be up to 2%
   •   HSE derogation would be required for >0.2%
• Siloxanes were likely to be present in the biogas
   •   Additional filtration equipment would be required
• The calorific value from the bio-methane would be lower
  than the existing network values
   •   Enrichment with propane would be required
• Costs were likely to be high – SGN IFI Funding used
• The project could be implemented in 2010 and would
  therefore provide valuable learning ahead of RHI
  introduction in 2011
                                                            15
How can AD Biogas become
Bio-methane
• Bio-gas from an anaerobic digester contains typically
   Methane = 55 – 65%   CO2 = 35 – 40%          O2 = 0.1 – 0.5%
   N2 = 0.5 – 2%        H2S = 200 – 2,000 ppm   Siloxanes (sewage only)

• Natural gas contains around 90% methane, with ethane, propane,
  butane, CO2 and nitrogen making up the rest.

• To inject Biogas into the gas grid it is necessary to clean it and
  upgrade it to biomethane

• Bio- methane is around 98% methane content



                                                                          16
The Didcot Project
Didcot Project – Before
injection (April 2010)

 Digester     Gas Bag     Flare




                                  18
Why Didcot ?
• Existing Sewage Treatment Works with 2 Digesters
  producing sufficient waste biogas
• Thames Water interested in the SGN proposition to
  clean up the biogas, upgrade and inject into
   the local SGN grid

• Practical details:
   •   Resilient local Network within 400m of site
   •   Available space
   •   Unlikely to have issues with planning authorities


                                                           19
Didcot – The ‘GREEN’ Gas
process




   Biomethane




                           Biogas
Biogas Clean-up and
  upgrading Plant
                                    20
Site Location


  Connection
                Residential Area
  to Gas
                that will use new
  Network
                   gas supply



Location of
New Plant




                                    21
Biomethane – The Process
                                                                                           Electricity
             Typical Bio-gas                                                                Output
                                      Gas               Gas Engines
  AD           60-65% CH4           Storage
               34-36% CO2
                1%    O2
                                                                                                         Flare



 CO2       Filters             Bio-gas Clean
                                 Up Plant
                               (Water Wash)

                                                                             Out of Spec
                                                                             Bio-methane
           Bio-methane
                               Propane
          97-98% BioCH4                                                           Network Entry
                               Upgrade
            0.3%    O2
                                                                                  Valve (ESD)


                                                      Bio-methane to Grid
                                                       Entry Equipment
                                                    (Network Entry Assets)



                               Network Connection
  Existing Gas
  Network                                                                                                    22
                                Filters for Siloxanes
                                      and H2S

Site Layout
Water Wash
 Process
  Plant




                                                    Propane Storage
                                                    and Blending Plant




 Gas Analysis
 equipment




                Biomethane
                to Grid Plant




                                                                         23
Didcot Project (Apr – Oct 2010)
First Biomethane to grid plant in UK


                                           DIGESTERS




                                         GAS
UPGRADE                                STORAGE
 PLANT -
PROPANE



                                                                TELEMETRY




                                             CUSTODY TRANSFER
           CLEAN UP                                                     24
                                             STN
           PLANT
Biogas Clean-up and
Upgrading Equipment
• Established Water scrubbing
  technology
    • Removes CO2
    • Removes H2S
    • Removes most siloxanes
    • Dries the biogas


• Additional filtration to ensure
  no siloxanes enter network

• H2S captured when it is
  removed from the water and
  not vented to atmosphere


                                    25
Propane Enrichment




Propane               Mixing            Propane Tanks refilled by Tanker
Storage Tanks         Vessel            every 3 to 4 weeks

Industry Review Group (GDNs, shippers, REA, Ofgem)
Sept-Oct 2010 agreed that adding propane to meet FWACV was necessary to
ensure customers were not being disadvantaged by bio-methane injection
                                                                           26
Biomethane Injection –
Equipment and Regulations
Gas Transporter must ensure :-                   Regulation Requirement

 Gas Quality Measurement                         GS(M)R Reg 8 Schedule 3 pt 1

 Pressure Control of gas delivery into network   GS(M)R & PSSR

 Stenching Agent injection                       GS(M)R Reg 8 Schedule 3 pt 1

 Volume Flow Measurement                         GS(M)R & Gas (Calculation of Thermal
 to enable calculation of gas quality            Energy ) Regs

 Gas Flow weighted average CV to                 OFGEM Direction under the 1996 Gas
 measure/record the energy of the gas            (Calculation of Thermal Energy ) Regs



        COMPLIANCE -Telemetry to monitor & record to Gas Control Centre
                 SHUTDOWN - Emergency Shutdown System (ESD)                              27
Gas Network Considerations

• Key considerations that the project had to recognise -

   •   Charge to Consumers           CV
   •   Consumer Safety               H2S & Wobbe Number
   •   Network Integrity             Water dewpoint & Oxygen
                                     (internal corrosion)

• Existing Constraints

   •   Currently only one OFGEM approved device (Danalyser)
   •   Siemens Microbox (FWACV hardware – supervisory software)
   •   Total sulphur & H2S measurement (MAXUM)
   •   Hydrocarbon dewpoint measurement
   •   High Pressure Metering Information System (HPMIS)
HSE - GAS SAFETY – GS(M)R
Fast Acting and Shut Off ( ESD)




    Fast acting gas quality        Emergency Shut Down System
     sampling equipment
                                                                29
 (H2O, H2S, S, CV, H2, O2 , etc)
GAS SAFETY – Stenching
Agent




            Odorant injection system
GAS SAFETY - Pressure
Control & Metering

  Accurate flow
  measurement




                  Pressure control – entry into 2 bar MP
                                                           31
OFGEM - Thermal Energy

                        SGN as the gas transporter were Directed
                        by OFGEM to use an approved type
                        Danalyser ( Gas chromatograph) that
                        enables highly accurate sampling.
                        Accurate to around 0.14 MJ/M3 (less than
                        0.4% error)
                        Accepted that this is an expensive solution
                        but there was no alternative for Didcot 2010




 700 Series Danalyser
                                                                       32
Completed Project (1)

                                                                      Digesters



     Propane
     Storage
                                                                  Gas bag

Propane mixing
and injection                                                   Thames
                                                                Water control
                                                                room
H2S and
Siloxane
filters
                                 Energy and quality Measurement,
           Biogas clean-up and   odorant addition, telemetry to Gas        33
           upgrading plant       Control Centre
Project at Completion




                        34
Project at Completion (2)




                            35
Project at Completion (3)




                            36
Project Learning
Successes – All in it
together!!
Co-operation of          HSE       -    Positive support for 2% Oxygen
Regulatory Bodies                      exemption
                         OFGEM -       Timely Letter of Direction
                               -        Expedited verification of Danalyser
                                       and other directed equipment

Single Party Delivery    • SGN lead project delivery as principle contractor
of Project               supported by our technical partner CNG Services Ltd

Modular Construction     • Excellent H&S record on congested site
                         • Significantly reduced construction period


Output of the Technology •   Bio-methane quality of clean up plant established
                         •   Propane requirement less than anticipated

                                                                              38
Learning
•   Location of Anaerobic Digestion - near gas grid
•   Capacity of the gas grid must be able to support facility
•   Operating pressure (IP or MP best)
•   Clean up technology and AD must be designed together to meet gas
    and energy quality requirements – retrofit process performance
    difficulties
•   Income balance between CHP (Fit’s) and grid injection (RHI) is
    attractive
•   Network Entry Agreements – Must be appropriate
    •   Measurement
    •   Telemetry
    •   Nominations – link to gas sales
    •   Communication
•   Design and Build Agreements – need industry standard
    •   Maintenance
    •   Ownership and Responsibility for Plant
    •   Plant Redundancy / Availability
                                                                       39
Future Challenges for
Bio-methane Injection
Technical Challenges for
Biomethane Injection
   Technical barriers to Biomethane growth in UK
• Oxygen content / specification - GS(M)R – is it appropriate at 0.2%?
• CV enrichment with propane – not seen as green
• Cost - Gas Quality / Thermal Energy equipment
    •   Regulations and systems are designed for large volumes of gas.
    •   GSMR data duplication - clean-up and network entry plant.
    •   Increase diversity of suppliers for network entry systems
• Network Entry Agreement
    •   Historically designed for large facilities, need to be reflective of smaller
        biomethane sources.
• Network Capacity Constraints
    •   Capacity re-engineering and suitable models to facilitate biomethane
        entry
• Gas Transporters Licence exemption
                                                                                       41
    •   Class Exemption from section 6A of Gas Act for Biomethane
 Future Challenges for
 Biomethane Injection
   Socio-economic barriers to Biomethane growth in UK

 Clarity on ownership and funding for network entry equipment.

 Incentives for GDN’s within next Price Control Period?

 RHI degression from 2012 ?

 Feedstock suitability – varied feedstock contaminants / landfill gas 2012 ?

 Project Funding – (Energy from Waste AD facilities)


                                                                            42
Conclusions

       Bio-methane could supply up to 50 % of domestic gas load here
       in the UK.

       Bio-methane into the Gas Grid is far more efficient than into the
       electricity grid providing a sustainable gas supply

       2020 UK Government target - generate 15% of national energy
       requirement from renewable sources

       The Gas networks currently have the infrastructure to deliver
       this energy supply to the majority of our consumers .

       Bio-methane injection is the best way to supply this low Carbon
       energy into millions of homes and businesses

                                                                       43
The potential is huge…..

         Thank you

          Alan Midwinter
     alan.midwinter@sgn.co.uk


          www.sgn.co.uk
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