Saturday, August 2, 2008

TNB-ACEM Dialogue 30 July 2008

On 30th July 2008, ACEM and TNB held a dialogue at TNB HQ, Petaling Jaya. The following persons attended


From ACEM: Ir. Dr. Abdul Majid Abu Kassim, Ir. Wong Shu Leong, Ir. Looi Hip Peu, Ir Wong See Fong, Ir Toh Ai Ching

From TNB: Yg Bhg Ir Hj Dato' Amir Nordin, Hj. Zaharudding Tajul Arus, Hj Roslan Ab Rahman, En Mohd Niza Wan Zin, Hj. Megat Said Megat Ramli, Dr Leong Yow Peng, Hj Abu Bakar Ismail, Hj. Mokhtar Ishak, Ir Nirinder Singh, Dr Abu Hanifah Azer, Hj. Mohd Hadi Sobod

TNB delivery system

Though there are still some complaints regarding TNB delivery system (connection of supply, late in reply, inconsistent requirement etc), the author is of the opinion that since the publication of the handbook, TNB delivery system has improved somewhat compared to a decade ago and tremendously compared to 2 decades ago!

Specifics issues touched on during the dialogue relates to a complaint by a member on 33kV supply;

  1. Onerous charges for hydraulic pipe jacking. TNB reply that this is beyond their control as it is imposed by DBKL. HPLooi remarked that he had a recent case involving 6km telekom cables in the center of KL city where DBKL DID NOT impose any pipe jacking charges;
  2. Inconsistent requirement e.g. 10m clearance for transformer room. TNB inform that they will look into including standardised conditions in the handbook for 33kV PPU. The author is of the opinion that whilst you can standardised single/double chamber substation, we should not promote a highly standardised version for 33kV PPU (whether outdoor type, standalone or incorporated into complex). The undersigned has a lot of experience in designing 33kV/11kV, 132/33/11kV PMU, PPU etc. and especially where space is a constraint and a premium (city centre, central business district etc), leeway should be given to the experienced design consultant. With regards to unreasonable demand by TNB personal during building handing over, the undersigned advice that if sufficient documetary evidence of approval is obtained during planning stage, you can successfully rebuff unreasonable demand AFTER construction (the author's experience).

Fire Fighting System

TNB is currently reviewing standard requirement for inert gas agent for TNB substation. Due to market force, pyrogen (being the cheapes) is currently the most popular. ACEM stand is that the old standard of CO2 is sufficient and the specification of inert gas agent is over specification and a drain on the country's resources.

TNB inform of cases of Pyrogen discharge wherein the residue from discharge is a problem for electrical switch gears. Ir Wong See Fong also caution TNB on gas agents which are not properly certified. Ir. HP Looi inform that Pyrogen is not an inert gas agent but an aerosal discharge. TNB inform that they cannot reject pyrogen as it is approved by Jabatan Bomba. Ir Wong (being member or is it chairman of IFE) should pursue this issue with Jabatan Bomba.

Standard Voltage 400V/230V


HPLooi enquire current measures taken by TNB to convert system voltage to 400V/230V nationwide. TNB answered in the affirmative and will make a public annoucement soon. All ACEM members should be informed that our national voltage is now 400V, 3 phase/ 230V single phase NOT 415V 3p/230V 1p.

Background to voltage normalisation

Back in 2002/03, Suruhanjaya Tenaga convene an industry-wide committee to look into initiative to bring our national voltage to 400V/230V from 415V/240V of which the author was a member (Ir. Melanie Cheng was my alternate in this committee). Reasons for this normalisation of voltage:

Countries who are members of the IEC (international electrotechnical commission) are standardising to 400V/230V. UK started in late 1990s and is already fully 400V/230V complaint, S'pore (I believe) started this in early 2000s and (I believe) is currently fully 400/230V compliant. Countries of IEC still NOT within the normalised voltage band are; China (380V/200V); India (415V/240V), Germany (380V/200V). Note also that IEC voltage standards are different, system-wise, from US voltage standards which have 200V/110V 2p/1p centre-tap.

Moving towards normalised 400V/230V will bring us in-line with international standards. Currently Malaysian exporters who serve the local market and export market have to test their product to 2 standards (the higher 415V/240V for local and 400V/230V for export).

Most electrical products (motors, lighting appliances etc.) can operate within a voltage band of (usually from 200V to 240V for single phase and from 380V to 420V for 3 phase). Most appliances are designed to operate at optimum characteristics (i.e. efficiency and life span) on 400V/200V. Therefore at 400/230V the life span of electrical equipment will (theoretically) be slightly longer.

Voltage Normalising Committee time-line (based on experience of UK & S'pore) of at least 8 years from 2003 to fully convert to 400V/230V):

  1. TNB was also in the committee. TNB commissioned a study in 2002/3 and concluded that the conversion is technically feasible and will not incurr substantial cost.
  2. Time-line; 1st stage declared voltage at 400V +15%, -6%; 2nd stage declared voltage at 400V +10`%, -6%, final stage declared voltage at 400V+6%, -6%. We are currently at Stage 2.

Steps for consulting engineer to design to 400V/230V:

  1. Change all specifications to 400V 3-phase; 230V 1-phase;
  2. Specify transformer at 11kV/420V instead of 11kV/433V
  3. Please check current carrying capacities again as 400V will incurr about 4% higher current compared to 415V. Coupled with voltage drop requirement of 6%, some design may be borderline.

SAIDI, Electrical System Reliability & Power Quality (PQ)

TNB table SAIDI figures for peninsular malaysia. SAIDI/SARFI statistics for Malaysia compares quite favourably with USA, Canada. Lowest SAIDI figure is S'pore, Japan.
ACEM enquired whether SAIDI/SARFI figures which are localised are available, as the figures published by TNB are national average only. These figures are important for consulting engineers as they are frequently requested to provide such figures and in the experience of the author, many (TNB) district engineers are usually not conversant on this issue. TNB will look into providing said figures at district level.
TNB present an information request form on harmonics for filling by consumers. Though the form is not mandatory (ref: MAPA form is mandatory) Consultant engineer is duty-bound to request consumers who may have non-linear loads to submit such forms.
TNB inform that standards on harmonics (IEC61000), voltage flicker, dips & sags (documents G5/4 and P28) will be baseline for approval of installation. ACEM need to monitor this issue. Ir. HPLooi highlighted during the meeting that ensuring compliance by consumer during CF may be easy. However ensuring that the public network comply may be a problem, as consumers may not comply (after CFO) period. Anecdotal evidence (in the authors experience) of "dirty" public network in Klang/shah alam south in mid 1990s contributed to repeated failure of a large precision DC motor in a facility in Shah Alam.
TNB is aware of the problem raised by HPLooi and has since resolved the issue.
Background SARFI & SAIDI are measures of system reliability. SARFI = System Average Rms Frequency Index measures voltage dips & sags and would be of interest to consulting engineer designing for a voltage sensitive facility e.g. state of the art steel mill; data centre; facilities for high precision manufacturing etc.
SAIDI = System Average Interuption Duration Index measures the statistics of voltage interuption. This figures will decide whether standby generators are required and for up to what extent. SAIDI figures may differ from locality to locality e.g. SAIDI for Jalan Meru Klang is NOT the same as SAIDI in Kulim hi-tech.
Electricity Tariff

Tariff increase was announce to come into effect on 1st July 2008. The new tariff structure is on a graded scale for domestic consumer. Those using less than 400W will not be affected. Those using above 400W and depending on your usage (escalating scale) you will be slap with an increase from 15% to 40% (including the undersigned due to heavy aircond usage). TNB spent some time trying to convince ACEM on the rationale to increase tariff. Go to TNB website http://www.tnb.com.my/

Note: However there is some hint that the govt may look at reducing tariff or provide some relieving measures for businesses (caution this is not confirmed).

Industry Statistics
As usual TNB roll out their statistics on the electricity markets:

  1. Generation level current 2008 at 20GW
  2. TNB reserve margin is 42% (this is at unhealthy level, an efficient market should have reserve margin of about 15%). In layman terms we generate much more electricity than we can use and electricity cannot stored or sold at a future.
  3. SAIDI index in 2000 was around 350 minutes (ie around 15 days outage per year), in 2004 was around 160minutes and currently in below 160minutes.

    USA /Canada currently has SAIDI of slightly above 200, Spore SAIDI is single digit, Japan is in the low 20s.

  4. Registered customers of TNB:

    Domestic - 85% (over 6 million consumers)

    Commercial – 15% (just over 1 million consumers)

    Industrial – less than 1%. (less than 40,000)

    Others (mining, street lights etc) 1%

  5. However compare with revenue earned:

    Domestic – 14%

    Commercial – 25%

    Industrial – less than 55%.

Energy Efficiency/ Demand Side Management (DSM)

DSM has been a topic since the last decade. FMM frequently request TNB to provide data on efficiency of generation and of IPP at national forum (at least the fora I was active in from 2002 to 2005). Example HP Looi inquire whether there are any statistics on max/min ratio for generation as this is ONE indication of generation/utilistaion. TNB was not prepared with answer to this issue during dialogue.

HP Looi raised the issue of peak/off peak tariff structure (C2 & E2) being not friendly to consumers, i.e. it do not encourage usage of peak/off peak tariff due to the higher MD charge for C2/E2 tariff. Due to this many marginal consumers e.g. large commercial complex or industry using above 2MW will not find it worthwhile to opt for C2/E2 tariff, example thermal storage system for large commercial user.

TNB noted this and inform that if ACEM has any proposal they will be happy to look on an individual basis. Some measures to encourage usage of C2/E2 tariff suggested by TNB may be:

  1. Extend peak/off peak hours from (current) 10pm to 800am to (proposed) 9pm to 9am, i.e. 2 hours extension.
  2. Some form of discount or tariff rebate for 7 years may be looked at for certain application e.g. ice storage for large complex (4000RT and above).

However, the proposals above are NOT currently published and if ACEM members have any proposal, they are welcome to discuss with Dr. Leong.

ACEM should inform all their members of this issue as energy will be an important market for ACEM members.

TNB request ACEM to provide a list of ACEM members who have expertise in Energy Efficiency as they have been frequently requested to provide such list by consumers (industry & commercial). ACEM should issue a general notice to members to register themselves as EE expert.

1 comment:

hplooi said...

Tuesday, 5 August 2008; 8.20pm

Dear Ir Looi,

Thank you for the important annoucement that will help us to blend in with the gobal objective. Suruhanjaya Tenaga had issued their circular on the matter.

Regards
Chris S F Chew

note: Ir. Chris Chew is the past president of TEEAM (go http://www.teeam.com