Swap Option

Description

This option allows equivalent supply points, one firm, one interruptible, to swap their supply status on a permanent basis, enabling the interruptible customer to gain a firm gas supply despite the constraints on the network. The firm site would correspondingly benefit from the lower transportation charges.

Sites suitable for this service

The following conditions would need to be satisfied to enable the site swapping from firm to be accepted as an interruptible supply point:

  • The meter or meters making up the interruptible supply points must use more than 5,860,000 kWh (200,000 therms) per annum.
  • The site must have equipment for daily metering or be upgraded with such equipment.
  • The proposed interruptible site must be able to cope during periods of interruption at which time the interruptible gas load will not be allowed to flow.

National Grid would need to test whether the loss of interruption at the one or more sites is physically compensated for by the one or more firm sites changing to interruptible. This test would need to be undertaken across the whole network from a local to national level.

Rule of thumb guidelines to help select compatible sites are as follows:

  • Firm site Supply Point Capacity (also known as SOQ) maximum daily consumption must be at least 90% of the interruptible sites SOQ.
  • Firm site Supply Point Offtake Rate (also known as SHQ) maximum hourly consumption must be at least 90% of the interruptible sites SHQ.
  • The Firm site must be in an exit zone which incurs a higher transportation charge.
  • Once accepted by National Grid neither site can re-apply for a SWAP within 12 months of effective change.

Disconnected sites can also be included, if they stopped taking gas within 12 months of the proposed swap.

Benefits

  • Allows a site to swap from interruptible supply point to a firm supply point even when there is no National Transmission System (NTS) capacity available.
  • The site swapping to firm does not incur NTS reinforcement cost, local reinforcement may be required, if so this would be chargeable.
  • Any number of sites can swap, these sites do not have to be owned by the same gas consumer or supplied by the same shipper.
  • Can eliminate capacity charges for sites which have been isolated.
  • Compatible with IFA, which would allow capacity management and flexibility for both gas consumer and shipper. Thus enabling a proportion of the site load to burn during an interruption period, without incurring a failure to interrupt charge.

This swap can occur at any time of the year subject to current nomination and confirmation timescales. The firm site would need to be nominated and confirmed as interruptible prior to the interruptible site being nominated and confirmed as firm.

Service Request Details

For gas consumers to progress a Swap Option request further, please provide the following information to your gas shipper/supplier who will instigate the process with xoserve. (xoserve will operate on behalf of all transporters).

Shippers should apply for this service by contacting their xoserve Shipper Services Customer Advocate Officer.