Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) Safe operation of Natural Gas Appliances Fueled with Hydrogen/Natural Gas Mixtures (Progress Obtained in the Naturalhy-Project) Dr. H. de Vries, Ir. O. Florisson and Ir. G.C. Tiekstra N.V. Nederlandse Gasunie 2nd ICHS, San Sebastian,

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD)  Preparing for the Hydrogen Economy by using the existing natural gas system as a catalyst Socio-economic and LCA aspects Safety Durability of pipeline material Integrity of pipeline system End-use and separation Naturalhy project  Physical and Chemical properties of Hydrogen differ from Natural Gas, with impact on:

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) Preliminary Conclusion * = Based upon current testresults, more tests are planned First indications: Max allowable Hydrogen for End-use might be the most limiting Integrity & Durability* Safety & Risk* End-use 0100

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) Thank you for your attention Gjalt Tiekstra Coordinator Naturalhy project

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 5 Safe operation: NG appliances: NG/H 2  Focus on domestic appliances  [H 2 ] max limit by Wobbe index conditions in NG distribution  [H 2 ] max limit by combustion safety aspects (light back) Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 6 Common safety practice in NG appl n  Gas Appliances Directive (GAD): Council Directive  About 70 harmonised standards on appliances and fittings  EN437: Test gases – Test pressures – Appliance categories:  Gas classification: Wobbe index: W = H s /, (T 1,T 2 ) (MJ/m 3 )  Type testing: short term tests of new appliances Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 7 Distributed gases and Test gases Gasunie, 2nd ICHS ’07 (overheating limit gas) reference gas light back limit gas flame lift limit gas W EN 437 group test range distribution range: “normal use” incompl. combustion / sooting limit gas

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 8 [H 2 ] max limit by distribution condition Gasunie, 2nd ICHS ’07 W W max EN437 group W max distr W min EN437 group W min distr W NG W NG/H2 [H 2 ] max Distribution condition: W NG/H2 ≥ W min distr > W min EN437 group

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 9 Premixed appliance operation Gasunie, 2nd ICHS ’07 FUEL GAS C x H y,N 2,H 2, …AIRN 2,O 2, … flow rate F flow rate A constant flow rate F + A Burner in appliance vuvu cold mixture:  prim : fuel-rich or fuel-lean primary flame front SLSL

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 10 Premixed appliance operation (2)   prim = (F/A) / (F/A) stoich  Behaviour upon changing fuel gas composition  Constant fuel gas pressure, constant air flow rate  Stable flame front: appliance safety (S L = v u ) FA Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 11 Risk of light back with H 2  Light back: when everywhere in the flame front S L > v u holds, the flame will propagate upstream into the burner  Well-known: S L (H 2 ) > S L (hydrocarbons)  CH 4 /H 2 mixtures are sufficiently representative for NG/H 2 mixtures for the present purposes Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 12 S L,  and H 2 admixture Gasunie, 2nd ICHS ’07 CH4 CH4/H2 = 70/30 CH4/H2 = 20/80 H2 fuel-leanfuel-rich  -shift:  ( NG/H2 ) <  ( NG )

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 13  S L for appliances (fuel-lean/fuel-rich) Gasunie, 2nd ICHS ’07 CH4 CH4/H2 = 90/10 CH4/H2 = 70/30

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 14 [H 2 ] max limit by light back (fuel-rich)  Practically useful [H 2 ] max values needed: experimentally comparing the light back behaviour of NG/H2 mixtures with that of a light back reference gas  “incipient light back” experiments on simple Bunsen tubes for most critical situations:  prim ~ 1.2 – 1.3  Gasunie (Prof. Dr. H.B. Levinsky et al) ; EET Program of the Dutch Ministry of Economic Affairs Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 15 Bunsen tube experiments Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 16 [H 2 ] max from incipient light back expts.  These Bunsen tube experiments set – for the first time – light back limited [H 2 ] max values for appliances that are light back critical upon H 2 addition (cooking burners) in general, as acceptable from common safety practice  At the same time, one should realize that existing NG appliances were not designed for long-term use with H 2 containing mixtures (corrosion, leakage)  large amount of testing effort needed Gasunie, 2nd ICHS ’07 * * *

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 17 Viewpoint: W-band  EN437 testgas Wobbe bands and Wobbe distribution bands apply on a national or regional scale  The appliances of different type all are connected to one and the same national or regional NG distribution grid  It is practical to consider detailed results from the viewpoint of a W-band  Safety aspect limited [H 2 ] max per appliance type  W NG/H2 = W min distr. determined [H 2 ] max limit  The lowest [H 2 ] max value counts Gasunie, 2nd ICHS ’07

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 18 H-band situation Gasunie, 2nd ICHS ’07 W max H W min H [H 2 ] max

Preparing for the Hydrogen Economy by Using the Existing Natural Gas System as a Catalyst // Project Contract No.: SES6/CT/2004/ NATURALHY is an Integrated Project funded by the European Commission’s Sixth Framework Programme ( ) for research, technological development and demonstration (RTD) 19 NG/H 2 : where are we now ?  It is not yet justified to present statements on what level of hydrogen concentration could be safely allowed in which specific natural gas distribution region  More clarity obtained on some essential H 2 admixing issues:  Combustion safety aspects of existing domestic appliances  The connection with the Wobbe distribution condition  More work needed on domestic appliances:  Fundamental calculations (straightforward)  Carefully designed experiments (straightforward)  Long-term corrosion tests Gasunie, 2nd ICHS ’07