First off, a very happy new year to all our customers and welcome back from your holidays!
POM Distribution Transformer - Early Monday morning, Port Moresby city experienced a total power outage on its grid at 5.00am. Our maintenance crews immediately kickstarted the restoration process while also identifying the fault to be at our Waigani Substation. Most parts of the city were eventually restored by 9am.
As we speak, we are currently still working on this Transformer (Equipment) Failure which is probably caused by excessive tap changing cycles. The tap changer is a critical part inside a Transformer of this type – like the gearbox in your car.
To remove, inspect, repair or replace this internal mechanism takes time. While this key transformer is out of action, it weakens the flexibility of the Grid leading to the requirement for load shedding and associated mitigation actions. We are working around the clock on this and expect this to last the rest of the week.
To continue to supply you with energy, we are working around this by re-directing energy under our normal protocol and procedures. Please keep an eye on our Facebook Page and WhatsApp Group updates in the interim. This is the approach we take nationally. A brief explanation on Transformers is outlined below.
Over the Festive season there have also been some disruptions to our fuel supply lines, most notably in Buka. This is not normal and we will correct this as soon as we became aware of issues around this. Permanent fixes to this are being put in place.
In addition, Christmas day saw the Ramu Grid subjected to power supply when the excessive rains led to penstock pressure (inlet) issues at our Pauanda Hydro Power Station combining with grid stability disruptions. The challenge on the Ramu Grid is that there is no redundancy i.e… if a major feeder goes down, there is no backup plan.
Now, our PEP investment project on the RAMU Transmission line on this Grid has been subject to local landowner delays but we are engaging with local and regional government to not only prevent further delays but in fact accelerate this key reliability and availability driven development for the Ramu Grid and it’s customers.
Looking longer term, PNG Power is finalizing the earlier communicated review of its asset management practices in order to better balanced decisions between short, medium and long-term actions. To this end, we will be refocusing our teams, nationally, to focus on planned maintenance and the associated on-site activities this entails.
I must highlight that these Planned outages will still be outages. But at least you will know when they will happen. Over time, these PLANNED outages will reduce the UNPLANNED events you are experiencing. This will take time and also investment as the downtime costs money as well as the parts that go into the work. But it is the only way to improve the performance of the system.
For this, we are working with all national, regional and local partners to support the cashflow needed to deliver this improvement.
What is a Transformer and why do we need them in a Power System?
Transformers are everywhere in our current lifestyles. Apart from the pole mounted steel cased distribution transformers you see in your street, transformers are everywhere in your homes. Your phone charger for example has a type of transformer that converts the 240V supply at your outlet to only 5Vs DC to charge your phone. Your ceiling fan, AC unit and even TV use some form of voltage conversion to be useful to you. If you own an electrical device, you’ve already held a transformer in your hand.
Simplified, a transformer is a stationary piece of equipment on a power system that transfers electric current from one circuit to another at the same frequency. When we say ‘a circuit’ in this instance, it’s a fancy way of saying a different voltage level with different power lines.
In Port Moresby, we transmit power from our Rouna Hydro and our Independent Power Producing partners at 66,000V. We use Step Up Transformers for this. When we want to Distribute the power from a Substation we use Step Down- Transformers in Port Moresby at 11000V and supply to your homes at 240V using a Distribution Transformer which you can see in the street on the poles or in Kiosks on the ground.
Getting technical, a transformer is made up of windings (the electrical parts), a Core (the Magnetic Part) and what’s called a Dielectric (often oil this is what insulates the Electrical and magnetic parts). These are encapsulated in a tank. It uses a 189 year-old principle called ‘electromagnetic induction’ to perform these voltage conversions.
Because of the static nature of transformers, they require little upkeep and can last from 30 years to some over 50 years. The longer they are used, they require more maintenance and have a greater chance of failing. Just like a car, the first years will need little major changes but once you reach a certain mileage, you need to change parts.
If a transformer fails in a system, it is detrimental to the overall supply of electricity. Imagine if the step-up transformer at Rouna fails, it doesn’t transmit power to the transmission lines. Or if the step-down transformer fails at Boroko Substation, the electricity will come from Rouna but the whole of Boroko can’t get distributed electricity.
It goes without saying that transformers for power systems are expensive. With over 750 power Transformers in Port Moresby ranging from K50,000 to K500,000 in cost it’s difficult to Prioritize which piece of equipment gets rehabilitated or replaced.
Transformers are a vital part in the transmission of electricity in a Power System.
Our technical teams are currently working on site to replace the transformer at the Waigani Substation, and therefore we will be rationing power supply from the substation.
PNG Power is working with donor agencies to improve the Port Moresby Transmission and Distribution system this year which will gradually improve our service to you in the next 5 years.
We thank all our partners, stakeholders and our customers for their continued patience on all fronts.
Work and stay Covid19 safe!
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