Issue 29 - System Operator Newsletter

Temporary management changes at the System Operator

Next Monday the 18th of August, we are making some management changes at System Operator that we expect will last 3 -4 months.  They are:

• John Clarke will begin a secondment to Transpower’s Grid Development Division, on work related to advancing grid upgrade plans.
• Kevin Small will be Acting Investigations and Planning Manager: 021 312 796
• Dan Twigg will be Acting System Operations Manager: 021 380 123
• John Campbell will be Acting Risk and Performance Manager: 021 390428.

Special Winter Schedule and National Winter Group

Publication of the System Operator’s Special Winter Schedule (SWS) began in May.  It was only ever intended the schedule would remain for winter 2008 and would cease publication in September. 

We will be seeking feedback from the National Winter Group on the future need for this schedule as part of a winter 2008 close out and look ahead to winter 2009.  We will hold that close out session in September.

Dry year planning and reporting

Although the dry year public campaign has now ended and virtually all planning work has been completed, we are still continuing to publish the daily updates to the Low Hydro Lakes Planning Weekly Report.  We will continue to do so while the South Island hydro lakes remain at their current ‘below minzone’ levels.

Frequency keeping costs

Selection methodology
The System Operator implemented a new selection methodology for frequency keepers in June, to increase visibility of frequency keeping costs to the System Operator in order to help ensure optimal dispatch.

We have commenced an analysis to establish the cost-benefit of the new selection process.  That analysis will continue over the next several months.  We expect a report will be provided to the Electricity Commission and the industry in September.

North Island frequency keeping band
In conjunction with several frequency keeping providers the System Operator conducted tests of several different frequency bands.  The test results are still to be fully analysed. 

Our initial findings for the South Island, a 10 MW band test found:

• no significant operational impact
• an increase in system inertial response noted
• that SPD modelling for the duration of this test initially indicated a reduced band may not result in water savings.

From the North Island, a 36 MW band test, we can make the following observations:

• a 36 MW band was difficult to manage operationally, given there are irregular half-hourly 50 MW load swings from industrial users
• the Frequency Keeper was contacted by the system operator to take action and come back into band on one occasion
• frequency management for the test period remained with in acceptable limits.

More in due course.

Market systems project (MSP)

This major project remains on its current schedule.  Site acceptance testing is targeted to commence on 18th August.  The current schedule calls for testing to conclude in mid-December with a hand-over to System Operator shortly thereafter for us to commence transition to go-live in March 2009.  Staff training recommences in earnest during September.  We are currently intending to run for a participant workshop in October where the major topics covered will relate to the new systems.  We will announce the workshop date when site acceptance testing is well underway.

MSP: frequency keeping selection and variable reserves

You will be aware that we recently introduced changes to the methodology for frequency keeper selection (live as at June 7th) and a new capability for dispatch of variable reserves (July 11th).

We remind participants that to provide both capabilities we have had to make changes to our existing software application tools.  The design of our new market systems does not incorporate the new capabilities.  This means that when the new systems are introduced into service (currently still expected in March next year) the frequency keeper selection methodology will revert to the previous form.  We will also loose the variable reserves capability.

For cost and timetable reasons it is not prudent to include both changes in the new market systems ahead of go live. We have put in train the development of changes to the new systems to be introduced as quickly as possible after the initial implementation. 

As is usual when introducing complex new systems, there will be a period immediately after implementation when the only changes made to those systems are changes identified during the initial period of operations and which require immediate fix.  The release of other changes to the applications will follow at scheduled intervals, in a planned manner.  We expect the variable reserves and frequency keeper changes to be in the first planned release of application changes.

We will ensure participants are aware of progress towards restoring the frequency keeper and variable reserves capabilities after the new systems go live.  Details from our operational procedure for variable reserves are at the end of this newsletter.

Planned Outage Coordination Process - review

The planned review of POCP for this year will not now proceed. System Operator resources have been affected by the demands of the dry year planning as well as the market systems project.  Consequently, and in the absence of any strong indications from participants that there are major problems with POCP, the next review will now take place in 2009.  We will call together a cross-industry group to participate in that review.

Procurement Plan review for 2008

We have recently posted our responses to public consultation on the draft Procurement Plan. 

The major issues discussed concern the following:

• pricing structure for procurement of fixed price/quantity frequency keeping (clause 105B)
• determining Interruptible Load pre-event (clause 126)
• clause 142.2  (measuring and recording resolutions at or below one second for FIR)
• improved performance and technical criteria for frequency keeping service providers
• publication of frequency keeping information.

Our full response is at: http://www.electricitycommission.govt.nz/submissions/commqualsubs/2008draftprcplan

Contact John Campbell  with any comments at:
john.campbell@transpower.co.nz, or 021 390 428

Automatic disconnection event on the UK national Grid

We thought participants might be interested in a 27th May event on the United Kingdom National Grid.  Although the scale of the UK National Grid and loss of generation compared to New Zealand is large, the report provides a useful insight and timely reminder of the importance of under frequency management.  It highlights how arresting a collapsing grid frequency through automatic demand disconnection (AUFLS) plays an essential role in maintaining security of supply to consumers. 

The report can be accessed at: http://www.nationalgrid.com/NR/rdonlyres/D680C70A-F73D-4484-BA54-95656534B52D/26917/PublicReportIssue1.pdf

Variable reserves: operational procedures

With regard to the variable reserves changes now in effect we thought it would be helpful for participants to understand the operational procedure our coordinators will employ when dispatching reserves at the appropriate time.  What follows is an extract from our internal procedure on which our coordinators have been trained.

Update to SO website

We have taken on board some of the feedback received over the last year on changes you would like made to our website.  While we can not implement all changes, we will be introducing some new functionality to the site later this month.

These changes include:

• friendlier urls
• customisable home page
• more graphical data
• ability to download data we show in the graphs as a csv file.

Note:  The change to more friendly urls will make it easier to remember your favourite pages.  The downside is that any bookmarks you have saved to pages on our site will need to be updated. We apologise for this but hopefully it will make it easier to remember urls!

Over the next few months we will continue to seek your comments on further improvements we can make to the website.  We value any feedback, so please give us your thoughts and ideas on how to make the site even more useful.