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ODes aCSESS Project Blog

Project progress report - week 29-30-31-32

So, looking at the crude numbers I haven't updated this blog for a month now. On my defence, I had my rightful dose of vacation, so that boils down to a couple of weeks of absence

Anyway, apart from the vacation, these weeks' work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Application for Finnish Academy PostDoc funding
  • SCC conference
  • Summer course on "Dealing with uncertainty"


ECOS 2015 paper extension

New data to look at, new errors / inconsistencies coming up.

So, the big deal this time is that heat demand and production do not correspond, when aggregated over the full year of operations. This is clearly annoying, as I do not incorporate any model for heat losses in the steam distribution system in the main model, so the two should be exactly the same.

The reason is: sometimes there is too much steam available, more than the demand, from the heat recovery. This might be due to two things:

  • The heat demand calculation is wrong. Or, to be a bit less pessimistic, inaccurate. 
  • There is some "inertia" element that is moving the unbalance around

So, although the first reason is certainly making up to a good part of the explanation, the second one is too, and it is much easier to deal with. So I spent some time trying to find a way to include the correspondent of a model for heat storage (that is, the steam drum) into the main model. 

At the same time, I tried to optimize some parameters around so to minimize the error on the consumption of the boilers. The results are somewhat encouraging, although we are still far from perfection. But at least now negative boiler consumption is no longer allowed...


Application to Academy of Finland

Finally the idea took shape. And I also think it is kind of nice. 

Basically, the whole concept is about how to optimally, and automatically, operate ships with complex energy systems. Sounds hard. Basically, the idea is that to save on carbon dioxide emissions, we will have to make systems more and more complex. If it is rather easy to control the system of a ship today (you basically just regulate the fuel going to the engines), it might not be as easy once we put some more systems on, such as wind propulsion, waste heat recovery and batteries, the whole question becomes more complex. 

How do we control this system? How do we make use of the good information we have from extensive sensor networks? 

These are (more or less) the answers that this project plans to address

The deadline is on the 27th of September, meaning that I have some time to refine it after receiving feedback.


Summer course on "Dealing with uncertainty"

Between the 28th of August and the 1st of September I attended a very, very interesting summer school at the Max Plank Institute of Magdeburg about "dealing with uncertainty". Basically, we had presenters from all over the world talking about their work of...well, doing engineering while dealing with uncertain quantities, parameters, inputs, and so on. 

The question was addressed for the following topics:

  • Control and uncertainty
  • Uncertainty in linear optimization
  • Process design under uncertainty
  • Measuring uncertainty

All in all, a very interesting summer school, with many interesting people. Good to be there!


SCC Conference

I finally attended the conference I had struggled to finish to write the paper for, this "Shipping in Changing Climates" Conference, London, 4th-5th of September 2017. Nice to be there, nice to meet new people and old ones. The atmosphere of this conference, being that most people know each other, is quite relaxed and friendly. 

I presented the first publication issued from my work about process integration in shipping. You can check it out here

Posted by Francesco Baldi at 17:35
Project progress report - week 27-28

These weeks' work has been devoted to the following activities:

  • Preparation of the MOSES-2017 Workshop
  • ECOS 2015 paper extension
  • Application for Finnish Academy PostDoc funding
  • Work for SCC conference
  • Osmose ET library 


Preparation of the MOSES-2017 Workshop

At last it arrived - the letter from the SNF with the results of the application I sent in - uh, when? like in May? - for organizing a workshop about modelling and optimization of ship energy systems.

It seems like I did not lose my touch for applications - it got granted!

So, these two weeks have seen quite a feverish activity related to the organization of the workshop. I had to:

  • Contact the speakers. Make sure they would come
  • Prepare a website for the event
  • Prepare the registration form
  • Prepare the abstract sumbission form
  • Design a conference invitation brochure
  • More...

But all this is for a good cause. Do not miss it: 23rd to 25th of October, in Sion


ECOS 2015 paper extension

We are getting close. Values are becoming more definitive. The analysis is iterating down to a point I might even be satisfied with it. Still, the heat demand part is unnvervingly inaccurate, but at a certain point we might as well simply live with it. 

At the end of last week, I got an interesting trail to follow about the heat demand. I'll keep you posted about it...


Application for postdoc at Academy of Finland

The work is going on on this side - in the last two weeks, many of the sections have taken a better shape and more detail. Still, there's much to be done: write down more section extensively, "clean" the text from inconsistencies (my view of the idea gets clearer and clearer the more I write, so the first parts often do not agree with the last) but at least things are moving forward.


Work for the SCC conference

I had one main reason for sending in an abstract for the Shipping in Changing Climate Conference: it would force me to do something related to that subject. 

It is working. Kind of. So I advanced a bit, but I am still quite far away from having anything of value to present. Let's hope I manage!

As it looks right now, I will try to address a simple case, just to show the potential of the method. In this, I will compare the use of  fuel cells (SOFC) and of Diesel engines, from the point of view of process integration. 


Osmose ET library

When looking for fuel cells to try to put on my ship, I realised that someone else surely had already modelled one, and that there must be a common shared repository with ET (energy technologies, the way the models of different units are called in Osmose) for people to use. 

When I realised that there was not such thing, I decided to gather some people and tried to do something about it.

That's how it all started. We are making plans. Stay tuned.

Posted by Francesco Baldi at 11:35
Project progress report - week 26-27

These weeks' work has been devoted to the following activities:

  • Reading Stefano Moret's thesis
  • ECOS 2015 paper extension
  • Application for Finnish Academy PostDoc funding
  • MSc project for control optimization of hybrid ferry
  • Osmose test function


Reading Stefano Moret's thesis

Stefano Moret is a PhD student at our lab (IPESE) at EPFL. He is going to graduate in September on the subject of dealing with uncertainty in the strategic planning of large energy systems. 

In short, he focused on the energy system of the whole Switzerland, trying to answer the question "How can we make a strategic plan for the development of the Swiss energy system in the future?" 

Methodologically, this turned out to be strongly connected to the question of how to deal with uncertainties when optimizing an energy system. This is true for any energy system, but particularly for the case of ones (like a whole country's energy system) where the uncertainties (on future prices of commodities, interest rates, etc.) are huge. 

So, Stefano focused on the following aspects:

  • Uncertainty analysis: how does each uncertain parameter affect the uncertainty of the final optimal solution?
  • Sensitivity analysis: how sensitive is the final optimal solution to the uncertainty on each individual parameter? This is very useful, as it allows to eliminate from the analysis (and, hence, simplify the otherwise huge task) the parameters that are the least relevant
  • Robust optimization: How can we optimize the system, being aware of the uncertainty, protecting ourselves by the worst outcomes while not compromising the efficiency of the system?

This was a very interesting reading!


ECOS 2015 paper extension

We got to a turning point: the calculations are basically over. 

So we had a Skype meeting, pointing the way through. The manuscript is starting to take shape, and although there is still much work to be done on the definition and verification of the calculations and the assumptions, I can finally see the light at the end of the tunnel.

TV (Tuong-Van Nguyen) took responsibiltiy for the critical part of clustering the resulting energy demand into representative days/hours/trips, while Fredrik and I will help in the practical implementation.

We are almost there!

And finally, thanks to Francesca (Belfiore, also PhD student at EPFL) I managed to have a correct implementation of the calculation of the bypass air in the main engines!!


Application for Finnish Academy PostDoc funding

Finally I have got an idea, and it is taking shape. I will not go much far into the details, but it is about autonomous vessels, wind propulsion, machine learning, gray-box modelling and condition monitoring. All, of course, for energy efficiency. 

Keep posted, it's going to be awesome!


MSc project for control optimization of hybrid ferry

Here there has been an unexpected turn of events: the responsible person at Damen Shipyards quit. 

However, this turned out not to be too bad: he put us in contact with two new people (Erik-Jan and Peter) who seem to be still quite interested in the project, although they asked to shift the interest a bit. 

The idea now is that:

  • We will focus on a ferry, rather than on a tug. Still hybrid, so who cares
  • We will have a particular focus on adaptive control: the controller should be able to adapt automatically to new routes without external inputs (or, with as few external inputs as possible). Challenge!


Osmose test function

The question of the Osmose test function came up again, so I took finally action.

Now the test function also works for Mac, and is implemented in the master version of Osmose on Github. So, anyone who has access to Osmose can simply download it and use the tests, as well as add his/her own ones...yey!

Posted by Francesco Baldi at 14:33
Project progress report - week 24-25

These weeks' work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Funding application for H2020 application on LNG for shipping
  • MSc project for control optimization of hybrid tug
  • Paper on application of machine learning to optimization of maintenance for ships
  • Abstract for SCC conference


ECOS 2015 paper extension

We are almost there! Now, almost all required calculations are performed, a large part of the code is appropriately debugged, and we can start getting some useful data out. 

Hereafter, some more updates

  • Finally, the calculation of the heat demand has been implemented. This time, I DO NOT use the information about the boilers' fuel consumption to calculate the demand, but I rather use that information as validation. The Result shows still potential for improvement but...we finally are getting something
  • Finally, the calculation of electric power demand was also implemented. The "major" effort (since electric power generation is measured onboard, so the determination of the total demand was trivial) was to identify the consumption of the thrusters and the HVAC. Some assumptions had to be made, and we will discuss them internally before publishing
  • I also implemented the analysis/modeling code for the heat recovery water system. This approach, based on the epsNTU method, allows for a much nicer estimation of the contribution of the HT cooling water to the onboard heat demand
  • Finally, the steam systems were also implemented

So, lots of things are moving. The nice thing is: the type of system analysis that I implemented made it MUCH EASIER to implement changes: since I define balance equations and connections, the algorithm is (at least partially) able to automatically adapt to changes in the system structure


Funding application for H2020 application on LNG for shipping

On friday the 2017-07-07 we had the new project meeting. Nothing much interesting to say, but things are moving forward


MSc project for control optimization of hybrid tug ferry

The contact previously representing Damen is leaving the company. But no worries, we have two more! One is Erik-Jan Boonen, someone I knew already and with whom I had been able to collaborate with ease. The other one is Peter Rampen, who I had met once before and who was very keen on keeping the collaboration alive. 

The project idea moved from looking at a tug to a ferry (no problem) and aims at looking a bit into adaptive learning control (maybe a bit tougher). We see how it goes, but they seem motivated! 


Paper on application of machine learning to optimization of maintenance for ships

Some big updates here as well. We contacted Par Brandholm at Laurin for some feedback and more data, and he responded very promptly! We (probably) got access to the Laurin/Marorka database again, and it seems (after some discussion) that we might have made our model work decently. And we can apply it to one more ship. 


We are now working on comparing the white-box models (the real one from Andrea and the "fake" one I wrote according to the instructions provided by the ISO. Let's see what it gives, the process is ongoing!


Absract to Shipping in Changing Climate Conference

I submitted an abstract for participating to the "Shipping in Changing Climates" conference in early September (4-6) 2017. The presentation will deal with a very standard application of process integration to a ship case. 

The main question now is: will I make it in time to prepare something?

Good question!

Posted by Francesco Baldi at 8:28
Project progress report - week 23

This week's work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Funding application for H2020 application on LNG for shipping
  • MSc project for control optimization of hybrid tug
  • Paper on application of machine learning to optimization of maintenance for ships


ECOS 2015 paper extension

The process of data analysis keeps (slowly) moving forward. Bugs are being fixed. In addition, the following was added:

  • Use of NASA polynomials for the calculation of enthalpy and entropy instead of CoolProp. Might be slightly inaccurate, but it is definitely way faster, also because it allows full vectorized computing
  • Added the cooling systems: splitter and merger on the HT cooling side, splitter on the LT cooling side, LT collector, LT distribution, Sea water cooler


Funding application for H2020 application on LNG for shipping

The description of the work package assigned to EPFL was performed


Definition of MSc project for control optimization of hybrid tug

We found a student! Navid, a student at the Politecnico of Milano, has successfully shown us his skills and received the green light for the project. He will be coming to EPFL in September 2017


Paper on application of machine learning to optimization of maintenance for ships

This activity started long ago, but I haven't been active for a while. The idea of the paper is to detect the effects of hull fouling on the ship's performance using machine learning approaches. 

My task into this project so far has been to implement, based on the same data, the ISO standard procedure for this. The idea was: if we can do at least as good as the ISO, this is good!

So the implementation was done - it does not work THAT well as yet, but we are working on it

Posted by Francesco Baldi at 9:36
Project progress report - week 20-22

These weeks' work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Funding application for H2020 application on LNG for shipping
  • Definition of MSc project for control optimization of hybrid tug


ECOS 2015 paper extension

This activity constituted roughly 80% of the workload for weeks 20-22. During week 20 and 21 we received the visit of Fredrik Ahlgren from Kalmar University, who is a partner in this project. 

The intensive work during these 2 weeks together, plus the continuation during week 22, boosted the development in the project:

  • We went through almost every single entry in the database, checking them for consistency and for usability. This resulted in a much-improved knowledge of the database
  • We included a validation for the engines fuel consumption, that in the end results in a very good agreement between measured and predicted consumption

This finally allowed to proceed with the debugging of the data processing (from input data to energy and exergy flows) code, that is currently under way but quickly developing.


Funding application for H2020 application on LNG for shipping

As the first stage of the application went well, we are now continuing towards the second stage of the application. This involved a first meeting with all the partners and is now leading to the preparation of the description of the work package assigned to EPFL


Definition of MSc project for control optimization of hybrid tug

As the second part of the project will deal with control, it is time to start looking further into this question. For this reason, a description for a MSc thesis project was prepared in collaboration with Damen Shipyards (Sandor Ivancsics is the main contact) and with the collaboration of Professor Colin Jones at EPFL. 

Posted by Francesco Baldi at 11:16
Project progress report - week 18-19

Thes weeks' work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Funding application for workshop on Modelling and Optimization of Ship Energy Systems
  • Osmose test function
  • Eurotrip #2


ECOS 2015 paper extension

These weeks have seen a boost in the efforts in this direction:

  • The code for the energy and exergy analysis is written
  • The process of checking the data pre-processing code is ongoing, slightly slowed down by some issues in the definition of the raw database
  • The code for printing out some results is at a good stage. 

Fredrik Ahlgren will be in Sion from the 30th of May until the 8th of June, which will further boost this activity (hopefully)


Funding application for workshop on Modelling and Optimization of Ship Energy Systems

The application was finally completed and sent to SNF


Osmose test function

One of the problems with Osmose is that when someone introduces something new into Osmose, it is not easy to be sure that it is still compatible with everything that used to work before, i.e. all old functionalities.

In order to somehow deal with this issue, some of the people in IPESE (me included) are working on creating a "test'function", that should be able to test as much of the old functionalities as possible. 

Here again, work is ongoing.


Eurotrip #2

I attended the final conference of the Joules project (Wednesday the 17th of May), carried out over the last 4 years by a large consortium of companies and universities working with the maritime business. The project, that involved almost all of the major European shipyards, dealt with the design of low emission ships using computational methods and led to the creation of a modeling framework that allows an easy sharing of models written by different people and actors based on the idea of FMU.

Attending the project conference, in addition to allowing me getting an overview and update about some of the latest developments in the field, was also crucial for networking:

  • I met people I new already, like Erik-Jan Boomen and Sandor Ivancics (Damen Shipyards), Gerasimos Theotokatos (University of Strathclyde), Sebastian Sala (Carnival Maritime), Pierre Marty (Bureau Veritas), Christoph Thiem (TU Hamburg), Penti Kujala (Aalto University). 
  • I made some new contacts, mainly from Fincantieri (shipyard, Italy), Meyer Werft (shipyard, Germany). 

All in all, it was a tiring, but very profitable trip.

Posted by Francesco Baldi at 9:45
Project progress report - week 16-17

This week's work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Funding application for workshop on Modelling and Optimization of Ship Energy Systems
  • Osmose improvement - chapter 3
  • Eurotrip


ECOS 2015 paper extension

As for the team's last Skype meeting, I provided a list of the correct column headers to be selected from the entire dataset (100 out of 2000, roughly). 

Now waiting for Fredrik to provide the updated dataset


Funding application for workshop

The workshop application is almost ready:

  • 8 candidates have accepted and are in the application. All of their CVs have been included
  • The CV and motivation letter by the applicant have been included
  • The application has been reviewed

The only missing thing is now the feedback of EPFL's Research Office


Osmose improvement - Chapter 3

The problem with the exhaust gas proves to be more difficult than originally thought, and cannot be solved with the workaround originally planned. Hence, I decided to add (or better, formally add) to Osmose the "Forbidden matches" concept. This concept allows the user to specify some matches among all possible stream matches that should not be allowed to happen. 

The process is ongoing. For the moment, I managed to write down all the equations. Now, the need for writing down the data input from the user to AMPL code, and testing are required.



The period from 03/05 to 11/05 was devoted to a pleasure/business trip in Europe:

  • In Hamburg (04/05) I met with Christoph Thiem, from TU Hamburg. He is a researcher working with various aspects in relation to energy efficiency and pollution from Diesel engines and has been involved in a significant number of measurement campaigns on operating vessels (Germany, Scotland), focusing also on taking measurements related to the estimation of the heat demand
  • In Hamburg (04/05) I met with Sebastian Sala and Ignatius Jukka, from Carnival Maritime. We presented each other's activities in relation to energy efficiency. I described them my project and following their interest we had an informal agreement on sharing data and technical documentation for one of their cruise ships.
  • In Gothenburg (08/05) I met with Selma Brynolf from TU Chalmers. She's a former colleague from my time as a Ph.D. student at Chalmers and works with LCA analysis and global energy models for fuels. We discussed our possible future plans for collaboration, and in particular about one funding application to FORMAS (Swedish funding agency) where I would have a role for the optimization of ship energy systems using non-conventional fuels
  • In Helsinki (09-10/05) I met with Kari Tammi and with a number of his colleagues from  Aalto University. It was particularly interesting to meet professor Pentti Kujala, responsible for the MSc program in Naval Architecture at Aalto University. He was particularly interested in the idea of a short course about optimal design of ship energy systems, and we drafted a tentative plan for the system. I also met with other future colleagues.
Posted by Francesco Baldi at 9:16
Project progress report - week 15

This week's work has been devoted to the following activities:

  • ECOS 2015 paper extension
  • Course in Model Predictive Control
  • Funding application for workshop on Modelling and Optimization of Ship Energy Systems


ECOS 2015 paper extension

The work of conversion of the code from Matlab to Python is ongoing. The data analysis for the main and auxiliary engines is completed


Course in Model Predictive Control

This week's lecture focused again on Robust MPC. The idea is that our MPC must work also when there are unpredictable external disturbances. We saw how this could be done in an Open-Loop MPC, but also that this is rarely (if never) done in practice. 

We also saw that we can also implement this in a different way, doing "Tube MPC", a form of closed-loop MPC, based on the optimization of a control action for the "nominal" system, plus a control function that depends on the error. 


Funding application for workshop

The original idea of organizing a workshop about Modelling and Optimization of Ship Energy Systems is taking shape:

  • The workshop will be held in October 2017 (23-25)
  • 10 potential participants were contacted. 8 accepted, and have sent (or will send soon) their CVs for the application
  • The rooms are booked
  • The application is written (needs to be checked)


Posted by Francesco Baldi at 18:50
Project progress report - weeks 13-14

This weeks work (halved by Easter holidays) has been devoted to the following activities:

  • Process integration applied to a chemical tanker
  • ECOS 2015 paper extension
  • Course in Model Predictive Control


Process integration applied to a chemical tanker

Finally all "programming" aspects have been fixed and Osmose has been updated in order to include them. To summarize:

  • Fuel input and, more in general, any flow can now be expressed as a function of the load (size) of a component using a relationship of the type y = ax + b (instead of y = ax)
  • A cost linearizator has been implemented for nonlinear cost functions
  • Piece-wise linear interpolation has been implemented

The work then focused on taking care of a number of details that had to be fixed concerning the specific project under study. In particular

  • I updated the specifics of the main engines
  • I included realistic values for heat demands of different types
  • I set a minimum operational load for all prime movers (main engines, auxiliary engines, boilers) equal to 10% of the maximum load
  • I included a model of an electrical heater
  • I included a model of an Organic Rankine Cycle (ORC), with cyclopentane as working fluid, with variable condensation and evaporation pressure, to be optimized in a master-optimization level
  • I included a "chimney" component, where exhaust gases are cooled either with an exhaust gas boiler, or they are simply released to the environment. This allows for full freedom of Osmose to optimize at what temperature the heat recovery can happen


ECOS 2015 paper extension

Work continued on the extension of ECOS 2015 paper. In particular, I prepared the data structure for the generation of the required data for the energy and exergy analysis. 

The work particularly focused on the painstaking process of translating the original Matlab data processing scripts for the energy and exergy analysis to Python. The idea is to create a full structure with all the data for all flows entering and leaving different components, so that it should (hopefully) then be easy to calculate energy and exergy efficiencies in an automatic way.


Model predictive control course 

This week's lecture of the MPC course dealt with the robust implementation of MPC. 

Starting from the contents of the previous lecture, we expanded the idea of robustness, generalizing the problem of having an MPC that works fine even when there are some external disturbances of different types. 


Posted by Francesco Baldi at 15:47
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