The proposed scope of works comprises development of the novel software decision support tool, development of ten best practice guides and a limited programme of training and awareness raising in National Grid and the wider sector (facilitated via the Energy Networks Association (ENA) and as appropriate other sector bodies such as Marcogaz).

Software Tool: The development of a software tool which will allow comparison of a range of candidate technology options for each study topic area in order to assist in determining which offers the best environmental cost benefit balance for National Grid and its customers. The tool will then be used to develop a series of generic best practice / BAT case studies which will compare the environmental cost benefit of a range of existing technology options and determine which represents BAT. There is no equivalent tool in use to specifically address the challenge of environmental cost benefit analysis for compressor ancillary equipment. The proof of concept for this approach has already been established, in the form of the Compressor Machinery Train BAT Evaluation Toolkit, which has previously been developed for GTAM. That tool, which also employs environmental cost benefit modelling and assessment techniques has received positive feedback from UK environmental regulators and compressor machinery train Original Equipment Manufacturers (OEMs) for its innovative approach to addressing multi-disciplinary environmental, technical and procurement challenges.

Best Practice Guides: The objective in developing the guides is to create a published resource that can be used by National Grid (and the wider sector) to inform designers, support investment decisions, environmental permitting and planning applications and justification on technology choices required by environmental and financial regulators. A wide range of topic areas relating to ancillary equipment and will facilitate better asset specification, plant design, reduced operating costs and potential environmental impacts will be studied, including best practice guides on the following topics:

• Natural vs. VSD enclosure forced ventilation vs. forced compressor cabs ventilation (including reduced ventilation during periods of standby operation)

   

• Gas seal technologies (eg. CobaSeal vs. CSR Barrier vs. Liquid film (wet) separation systems)

   

• Venting vs. flaring vs. storage / recompression and reinjection for fuel gas systems, compressor casings and pipework

   

• Gas vs. electric-hydraulic vs. electrically vs. air actuated valves

   

• Electrical vs. Gas actuated odorant pumps on transmission assets

   

• Use of compressed air for seals and other utilities

   

• Micro Gas Turbine vs. Diesel Fired vs. Gas Engine Standby Generation Equipment

   

• Low energy heating / cooling for compressor cabs and welfare facilities

   

• Fuel gas system optimisation (recovered heat vs. electrically / gas heated fuel gas, fuel gas pressure reduction expanders)

   

• Inlet air preheat (recovered heat vs. electrical heating vs. bleed air) vs. non-icing filters

   

• Micro-renewables for on-site energy consumption

   

• Low energy lighting (security, cab, welfare).

   

Benefits

The following can be identified as potential success criteria:

• Validation that existing technology choices represent the best environmental cost benefit balance

   

• Identification and evaluation of new / innovation technology options not previously considered

   

• Greater auditability and justification associated with investment decisions

   

• Improved development and update process for engineering standards (e.g. T/PM/COMP/20 ‘Management Procedure for Design of a Compressor Installation for the National Transmission System,’ and its subsidiary procedures)

   

• Time and cost savings for projects via access to a published library of case studies

   

• Investment decisions being made on the basis of a consistent evaluation method taking potential environmental impacts into full consideration

   

• Identification of technology options / practices with a high degree of potential viability, suitable for further evaluation under the NIA/NIC mechanisms

   

• Potential whole life cost savings associated with selection of more efficient equipment

   

• Potential carbon dioxide (CO2), or carbon dioxide equivalent (CO2e) savings associated with increased efficiency or reduced process gas losses

   

• Potential reductions in other emissions, resource consumption and environmental risks.