Konstantinos Kanellakis, Schneider Electric gave a presentation on ‘’Smart panels and energy audits: Optimize the electrical consumption of a vessel’’ during the 2016 GREEN4SEA Conference Awards, in which he covered the energy savings potential for a vessel’s electrical consumption. He referred to the technological tools available today to monitor, analyse data and create reports to help with decision-making on energy efficiency actions. He highlighted how important is to monitor in real time the vessel’s operation to avoid issues which may be critical for the electrical installation and key applications and conclude his presentation by stating the most usual applications on board the vessels, which offer high potential for energy efficiency with a fast return on investment.
Without data you are just another person with an opinion. At the end of the day we have to make decisions, so we talk about energy saving, green shipping but how are we going to decide which the actions that we have to take are and how can we measure in the end that what we did was correct and actually we have the savings that we expected? Firstly, I will give you an example with real application where we were discussing with a shipping company about selling one of our energy efficiency solutions, which is about using variable frequency drives to control the speed of the motor so that I have significant energy savings. The bad news for us was that the motors were of two speeds: high and low, they already had very good energy savings. However the ship owner wanted to check whether this is the optimal solution and accept it to install power metering and see what happens.
We made the installation for two vessels and after about three months when we checked the feedback it appeared that one of the vessels, on an annual basis, would have about 20,000€ savings more than the second vessel. The reason for this was that the crew of this vessel followed a better procedure in deciding when to run the motors at low speed. So 20,000 € may not sound much but if I multiply by 15 sister vessels, then I go to 300,000€ which is a significant number. Regarding the following graph we see that when we start at 100%, the normal consumption at this point the first step is just to fix the basics where I can monitor, and I can get the data analyze the data and see what I can do in order to have savings. If I just copy and paste the procedure of the first vessel then I can have the savings in the second one:
The second step is about using automation to make sure that we have the maximum savings. For example, in this same application when we analyze the data what we found out is that the maximum could be about 35,000€ per year. To do this we will not need to install the system with the variable figures or drives, which is the expensive solution. We are talking about installation of about 5,000 € per vessel for product, programming and commissioning in order to make sure that we will have the maximum of the 35,000 €. Therefore, when we go to automation we get more than that; our experience shows that 32% to 35% for any kind of electrical installation is possible and it is something that you usually do but the most important part is that I should keep monitoring and be very cautious about maintenance. If we let things on the road, after a period of time we will be back to the consumption where we previously was. At that point the pressure goes off, they go to manual mode and full speed, the sensor is strange but they do not go to the automated mode. This is a critical part.
The methodology that we follow is actually this cycle (see image below), because we have to go back and back again. The first step is to measure and analyze; we have to go usually on the ship to make a walk through audit, discuss with the chief engineer about the specificities of this vessel and may have sister vessels in different routes which may have completely different energy profiles and then we can understand which are the most important points to focus on. The next thing is passive energy efficiency to fix the basics: when you get out of the room, turn off the lights. The second point is active energy efficiency: install present sensors so that we know when nobody is in the room automatically the system will turn off the light and then we will have to monitor, go back again and when the situation changes, check again if we can have more savings.
And how can we do this on a vessel? The technology we have today is Smart Panels and Power Monitoring Systems. To explain this further we will use the equivalent of a car. In previous years the car would give me the fuel level, the speed, the general malfunction issue about the engine and an alarm. Today all this data goes to a processor with data from more sensors so we know how many km we can run until we need more fuel; if one of our doors is open, we can have a speed limitation or a cruise control or if we have a logistics company we can know where the track is, what the speed of track is and if this violates the speed limits and so on. When we try to implement that on a vessel, the first thing to do is to measure. We have power monitoring and circuit breakers where we can install extra modules to connect them to Ethernet; this applies even to miniature circuit breakers we have in our houses. This also gives us data about harmonics, the power factor, consumption, whether I have a thermal alarm, a trip, we can even reset remotely a circuit breaker. Then we connect this together in Ethernet and this applies not only to Schneider Electric products but for whatever sensor we may have pressure, flow, temperature. Then the crucial part is how to monitor and analyze the data to turn them to something that makes sense; just to get excel files with data is useless. Here, we have software where we can change the parameters according to what you want to monitor so that you have precise data about your applications. For example, you wake up in the morning whether in the last 24 hours you had some alarms on the vessels, you click on the alarm icon and you see which vessels these are, you can see if the fault has been recovered, how long it took the crew to solve the issue, if it is a repetitive issue so that you may have to take further corrective actions. You can check where your vessels are and check what the energy consumption of each vessel is and of course any other data that have been put inside the system or I can benchmark. Also, on equipment: whatever you want to analyze can be done through this software.
The next question that comes to mind is which are the applications that usually offer the best potential for energy efficiency. The easy one is power quality. If we improve power factor from 0.8 to 1 we can have about 2% improvement of the efficiency of the Diesel generator. We have a success story on this on a ferry where we improved power factor and the savings of the fuel were equal to 8 kw/h. But in the thousands of hours a ferry annually operates-this is about 700,000kw hours per year which 2-3 years ago translated in 80,000€ of savings per year.
Another recent example is the condenser. We use steam to discharge the cargo of a tanker; we have pumps for the condenser to return the water if we regulate the speed of the pump the water will get back at a higher temperature which is okay, but look at the savings: for a 75 kw pump our consumption is 9.3 kw. Another solution for which it was designed and implemented in more than 60 vessels in Greece, it is the engine room funds and sea water pumps. If we use variable speed drives for 80% of the flow we can have about 50% energy efficiency. For the systems we have installed, the average is more than 65% for the sea water pumps and 50% for engine room funds even if the current oil price with a return of investment from 1.5 to 2 years. Other applications which are quick wins such as lighting, or heating, ventilation, air conditioning for specific types of vessels, like cruises or ferries and of course reefers for containerships. However, one thing that we have seen with all those applications and audits we have done is why not go back and rethink the design of our vessels. This is a very recent case study for a containership of 13,000 TEU with 1,000 reefers. The standard solution to give power to the reefers is to have middle voltage power generation, go down to low voltage and then distribute to the reefers in low voltage. Our people had a different idea: they thought about distributing power in medium voltage. The study showed that in the middle voltage in the following cases we have about 60% to 70% the cost of the standard system, so it is about 30% cheaper and you also have savings on the losses of the cables; cheaper to install, cheaper to operate.
The analysis showed about 50 tons of fuel per year while availability was improved by 25%. Energy is not free, but to learn how to save it is free!
Above text is an edited article of Konstantinos Kanellakis presentation during the 2016 GREEN4SEA Conference & Awards.
You may view his video presentation by clicking here
The views presented hereabove are only those of the author and not necessarily those of GREEN4SEA and are for information sharing and discussion purposes only.
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About Konstantinos Kanellakis, Marine & Shore Connection Business Development, Schneider Electric
Konstantinos Kanellakis has been working for Schneider Electric for the past 9 years and is responsible for the marine and shore connection business development of Schneider Electric in Greece. In the past he has also worked as Group Product Manager and product application engineer for a wide range of industrial products. He has extensive experience on energy efficiency solutions for marine applications, with installation of automation systems and variable speed drives on many vessels. He holds a degree on Electrical and Computer Engineering from Aristotle University of Thessaloniki and a Master in Business Administration from Athens University of Economics and Business
