How Siemens Energy Enables the Global Energy Transition
Jens Dietrich, Siemens Energy AG
The transition to carbon-neutral energy production is one of the cornerstones for limiting global warming. Recent discussions about energy transition have focused on the "energy trilemma"—the need to find the right balance between affordability, reliability, and sustainability of energy.
Part of the solution is to strengthen the power grid for highly fluctuating distributed generation and feed-in from renewable energy sources. Siemens Energy is accomplishing this with solutions such as HVDC (high-voltage direct current transmission) and FACTS (flexible AC transmission).
The power grid of the future relies on power electronics and their control software. Therefore, the energy transition is also driven by software development. For this purpose, it is elementary to understand the grid as well as possible and to test the software thoroughly.
Working closely with MathWorks as a technology partner, Siemens Energy's Grid Solutions Control and Protection Department has extended Model-Based Design to study, develop, and verify complex power transmission systems. Simulating the plant on a desktop PC helps to "push left" in the v-model development cycle to test system behavior as early as possible with the same control software that is later deployed on hardware. This enables the development of a digital twin to analyze and understand fault scenarios and incorporate final system validation for the end customer with MathWorks products.
Leveraging this approach as an end-to-end development ecosystem helps in all phases of project execution—be it bidding, engineering, or system studies. Modern cloud-based CI/CD workflows extend this ecosystem to automate test and code generation and make it even more accessible to all engineers.
Using a model-based engineering ecosystem helps Siemens Energy provide answers and solutions to our customers and support them on their journey to clean and available energy for all.
Published: 7 May 2023
[AUDIO LOGO]
Hi, and thank you, MathWorks, for having me here today. My name is Jens Dietrich, and I'm the Head of Transmission Software Platform Development at Siemens Energy Grid Solutions in Erlangen, Germany.
Together with my team, I'm working on an engineering ecosystem to develop power system controls for large-scale energy transmission projects. Over the past eight years, we took the latest state-of-the-art software development techniques and combined them with model-based design to rethink how we develop, test, and integrate power energy systems.
But before I want to talk about technologies and tools, I want to talk to you about the global energy transition and how Siemens Energy enables it, because this is ultimately the purpose why we do what we do at Siemens Energy, and why we think about something like engineering ecosystems.
So when talking about the global energy transition, we are talking about global warming. And where we are talking about global warming, it is always linked to carbon dioxide emissions. So here, you see a graph for the energy-related carbon dioxide emissions from 2000 on until 2023. And you see it's a constant increase from 25 to almost 40 gigatons.
On the right-hand side, you see possible pathways for limiting global warming to certain limits. So let it be 1.5, 1.7, or 2.0 degrees Celsius. And if you look at the very left scenario, the 1.5 scenario, which is currently the one favored by governments and politics, you see that we have to reach zero carbon dioxide emissions by 2040. That state is called net zero.
But what does reaching net zero really means? It means that we limiting the steady growth on the left-hand side is simply not enough. It really means a decrease of carbon dioxide emissions by 100%.
And even if we allow ourselves a little bit more of global warming, let's say 1.7 degrees-- and by the way, this would already be devastating for a few countries-- we only buy ourselves 20 more years to reduce carbon dioxide emissions altogether.
So limiting global warming does not really need an evolution on how we produce and consume energy. It's rather a revolution how we do that. And this is what the energy transition is all about.
But as often in life, one problem is not enough. We actually have to solve three interdependent problems at the same time. And scientists call that the energy trilemma.
And the first problem is about energy security. Basically, the question is, how can we keep the lights on in the future? So the energy system must still be reliable and safe. The second question is about energy equity. So can we still afford energy in the future, or is it only a thing for the privileged few?
And last but not least, the energy sustainability, it's a question I brought up earlier. So is the future system contributing to net zero? And are we really able to produce and consume energy without emitting any more carbon dioxide?
When only looking at, for example, energy security or energy equity, you would most likely not end up with a system that will save any carbon dioxide. So for the energy transition, it's really about solving all those three problems at the same time, really a trilemma.
And let's look at our current status. So this picture is taken from the latest report on energy transition readiness from Siemens Energy and is published this year.
And if you look at the numbers, you see that even the best regions, Europe, North America, are far away from their 100% goal. The transition readiness in this case means the progress towards the goal of being carbon dioxide neutral. And maturity means the importance the endeavor is given.
And you can also see why Middle East, and Africa, and Latin America are behind on the transition itself. They have put a great emphasis on catching up. And especially Latin America, with lots of hydropower, has the potential to be a safe green powerhouse in the future.
So when you look at all those numbers, those graphs, I think it's obvious it's really time to act now. And the issue actually is not with identifying the problems. It's really about implementing solutions as soon as possible. And at Siemens Energy, we see different fields of action to do so.
The first one, and I think that's no surprise, is drastically expand the share of renewables in the energy mix, let it be solar, biomass, hydrogen, or wind energy. Especially wind, and therefore wind offshore energy, has a great potential in Europe in North America.
A great example, or a lighthouse project, if you want, are the latest Siemens Gamesa offshore turbines with up to 15 megawatts of power. They can ride through even the harshest wind conditions and have a giant almost 240-meter diameter of rotor. It's 40% more energy compared to the previous generation. And the prototype was erected in Denmark this year. And we are excited to see serial production next year.
The second field of action is exploiting existing infrastructure. And this may sound a little bit counterintuitive, because I was talking about a revolution not an evolution earlier on. But our resources are not unlimited. So we have to maintain energy security. So throwing away existing infrastructure is not an option.
So we need to close the gap between the old and the new technologies. And we have to think how we can refit existing power plants for higher efficiency. Especially combined gas and steam power plants now can reach to efficiencies of 65%.
But, also, we have to think about how we make the existing plants ready to operate at net zero. And the great example here is hydrogen-ready gas turbines from Siemens Energy and future hydrogen power plants. So when you refit a gas turbine for hydrogen readiness, you can feed up from zero to 100% of hydrogen into an existing gas turbine. So it can still operate as you operated before.
But with renewable energies, in the future, and especially when we have an excess of electricity we can't feed to the grid, we can use electrolysers-- and in this case, the Silyzer from the Siemens Energy portfolio-- to produce green hydrogen we can store in tanks and then feed it to the gas turbine. This gas turbine is then fed with 100% green energy producing green electricity as well as green heat for our cities.
Last but not least, we really have to strengthen the electrical grid. When we have more renewable energies, we have more fluctuation in the power in feed. And that we have to compensate with a more robust energy grid. Also, renewable energies are often not produced in the areas where the energy is needed. So we have large imbalances between regions.
A good example for that actually is Germany itself. We have a lot of wind power in the North and a lot of industrial consumers in the South. And, therefore, we have to strengthen and rebuild the energy grid to reduce those imbalances. Additionally, we have to think about new grid elements to control the energy and power flow. And a great example for that one is the HVDC converter technology.
But before I want to talk about HVDC, I want to explain what I mean with active elements. So, traditionally, we're talking about a linear energy landscape when talking about transmission. So from the last large generation on the left slide to very passive transmission, meaning through a lot of coppers and wires to the consumer on the very right. It's a unidirectional power flow. And the transmission only reacts to the laws of physics and is otherwise not controllable.
But, actually, our future is a complex and interconnected energy landscape. It's a mesh grid with multiple electronic elements to control and stabilize power flow. And this is what we call active elements. It is also more data-driven, as we need more information about the state of the grid at all times to operate it safely and optimally.
So active elements and especially HVDC grid connections play an important role. And this HVDC technology is actually proven one at Siemens Energy.
One of our great customer references is BorWin3. It has the potential to power one million households with 900 megawatt of power, bringing wind energy from the North Sea to the shore. It has a 160-kilometer cable connection operating at 320 kilowatts, a voltage you would usually see at large overhead transmission lines now put into a small undersea cable. Our customer, in this case, is a transmission system operator tenant, and the normal operation began in 2020.
By now, you're probably wondering what is this HVDC I'm constantly talking about? So let's have a closer look at the technology itself. HVDC stands for High Voltage Direct Current. And it plays a crucial role, as I was already mentioning, for offshore and onshore connections in the future.
For an HVDC system, the power is first converted from AC, alternating current, using a converter station located next to the power source, in this case, a wind farm. And the DC power is then transmitted through a transmission line, usually high voltage submarine cable or an overhead line, to a second converter located next to the destination. There the DC current is transformed back to AC. And then it is supplied to the local transmission grid.
HVDC transmission has a lot of advantages over current AC transmission, so the transmission you would see on the right side with a normal transmission grid, including lower transmission losses, better control of the power flow, and the ability to transmit power over long distances, especially when we are using cable connections.
And since HVDC is semiconductor-based, there is active control required to operate the system. So you could say that the controllers are the brains of HVDC. So control, which means software. And software was always a part of the HVDC development.
But, nowadays, due to the requirements and new interconnection landscape, HVDC becomes more and more software-driven. So the digitalization of the power grid requires us as the manufacturer to develop more advanced software function. And, therefore, we have to digitalize our engineering ecosystem as well.
And this journey started eight years ago for us. So we were thinking about qualities for a state of the art engineering environment and set ourselves three important goals. And the first one is that we wanted hardware independence. So we wanted to deploy the original control software unchanged on different hardware or software platforms.
The second one actually is a strong focus on system engineering. So the aim was to engineer and simulate the whole control software, including the electrical part on a local PC instead of any big hardware, [INAUDIBLE] simulators, for example.
And last but not least, we wanted to put a real strong focus on automation. So we wanted to have automated builds and regression tests, to run and evaluate the system probably nightly, weekly, on ever intervals we wanted, and preferably on cloud infrastructure.
So when we started, the first decision we took was to go with model-based design and MathWorks products. And, probably, when you start model-based design, you start with smaller functions, like, for example, a controller.
And soon you realize that you need some kind of modularization for building blocks that are often used. And you end up having a library of building blocks for example, in PI controller, you then can re-use in your controllers very often.
But Simulink can do much more than that. So we created a scalable architecture with model references and reference subsystem that goes from the very small blocks, to the control functions, to whole components, and even the whole HVDC system. Now, the focus switched from pure controller development to system development, system integration, and system testing.
And having this HVDC system at our local PC with MATLAB Simulink allowed us to do one more thing many people are talking about and probably you also heard about it. It's a digital twin. A digital twin is a term that is mostly used for very different things. And in our case, it's not a fancy free D model or has any fancy animation. But it's still a physical model of our electrical plant combined.
And I think that's the most important part about the digital twin combined with our original control software that also runs on the plant. So that Simulink-based twin allows us to test and verify our system early on as well as it allows us to develop additional services around it.
And one great example for that is our SensOTS cloud-based operator training simulator, where we combine the plant simulation with MATLAB Simulink with a real HMI to train our customers how to operate the plant.
So put into a cloud environment and connected via normal web server, this approach is very scalable and it allows remote training and no need to sit in front of the hardware setup where only one trainee can be trained at a time. All the trainees need is a web server to enjoy a real plant-like training experience.
But, actually, our ecosystem is not just about simulating and testing better. It's really about bringing development teams together. You're probably familiar with the situation where different development teams have a set of languages, compilers, environments, and even programming languages to work with.
There could be one team tasked with developing a control function, which is later deployed to an FPGA. And there's another team developing also a control function, which is targeting a DSP. And there could be a third team probably doing system simulation, which to rebuild both the controls, and the electrical part, and the simulation tool that runs on a normal PC.
The integration is usually done at a very late point in hardware-in-the-loop setups. And the hardware-in-the-loop setup and the offline simulation are two different worlds and really hard to compare.
We call that kind of engineering swimlane engineering, because there are strong boundaries between those development lanes that prevent collaboration and the exchange of information. Basically, the organization shapes the development process and also shapes the type of architectures and software used.
So when switching to model-based design and Simulink, we put all our control engineers at the same place. To be very precise, we put that in the same Git repository. So now, all teams develop in the same modeling language, Simulink, and code generation details, compilers, and tool-change are handled centrally. Tests can be already executed while developing as model-in-the-loop setups.
We have now this state of collaborative engineering where the development extends across the borders of the organization. Also, we have the single point of transformation for our target platforms. We can now deploy specific controllers to the respective hardware platforms with embedded coder or combine the entire system model to an executable.
Also, the same controller can be used for different things. It can be deployed on a DSP. Or it can be deployed into the simulation tool which later runs on the normal PC.
I recently heard the sentence that model-driven development is when you do more than one thing with the model. And I think this whole ecosystem is just about that. And we found one more thing we can do with our models. And this is running them in the cloud. We could simulate them in the cloud, and we could do the build process in the cloud just by pushing the models into the Git version control.
This workflow is commonly known as CI/CD, so continuous integration and continuous deployment, and it works not just only for C++ and Java code, it really works perfectly for large Simulink models as well. So we have created a system where all the engineer has to do is to push the changes to Git, the automated pipelines pick up the models, verify the changes, and deliver a freshly compiled binary package to the hardware side.
We work with the latest technologies such as Docker and AWS Elastic Compute to virtualize MATLAB environments so we can dynamically spin them up for many parallel MATLAB machines and tear them down if we don't need them anymore. This creates an ecosystem where complex tasks like automated testing and building become more accessible to the engineers as well as removing the limitations of the PC in front of us.
But let's go back to the energy landscape we came from. While previous activities were focused purely on the ecosystem within a project, we need to consider the new reality on the market.
Right now, we see an acceleration in the energy transition. Governments are pushing for new offshore and onshore connection to reach their carbon dioxide targets. Therefore, we need to expand our capabilities as a manufacturer to execute from a few parallel projects per year to a dozen parallel projects per year.
And this is where we could really harvest what we started eight years ago. Due to the investment in model-based design, we came up with a new way of parallel project execution we now call reference project lines. Think of it is our version of Volkswagen's MQB platform, but this time for the project business, a business where unit volumes are quite low but customer requirements and system complexity are high.
So we use software and hardware building blocks-- let it be Simulink libraries and models on the software side, and hardware blueprints, and hardware typicals on the hardware side, along with processes and tools, to create our reference project that covers most of the requirements and functions.
We put everything in we learned along the way with modularization, automation, and project ecosystems. To stick with the automotive comparison, you can say that we built an engine-- a car with an engine that has tires and a standard navigation system. It can drive and get you from A to B, but it's probably not what you want at the end. You want a different color. You want a larger engine, and probably also a lane-assist to keep you safely on the road.
So compared to our domain, that means that we have an HVDC system that can safely transmit power. But it doesn't provide all the grid services that the transmission system operator needs.
And now comes the phase that we call data engineering. That's where we bring all those customer-specific requirements in and put them on top of the reference project line that we already have to create that final customer solution, still using the same tools and technologies that we used before. So at the end each, customer solution is really a unique and specially tailored solution with all the requirements and national regulations the customer needs.
Reference project lines aim to deliver a highly customized solution by standardizing the essentials of each project, and just that, allowing for more predictable and efficient project delivery. And there are a lot of projects to come.
So especially for the onshore connections in Germany, the so-called corridor projects, which deliver the energy from the North to the industrial centers in the South, Siemens Energy provides free interconnectors. The first one is Ultranet, the first of its kind hybrid AC/DC overhead line connection with also a first-time application of multi-terminal HVDC in the future.
The second one is SuedLink, with a 700-kilometer underground cable to reduce the impact on the environment. And the third one is SuedOstLink, which has a 500-kilometer hybrid cable and overhead line, also a first-time application.
All of these three projects have two gigawatts transmission capacity. So we have six gigawatts capacity at the end. That is roughly the equivalent of five nuclear power plants.
And we see this same potential and even bigger potential on the offshore side too. So when you look at wind turbines and the development where the turbine in the early '90s had roughly half a megawatt of power, you see now prototypes for offshore wind turbines with 13 to 50 megawatts. Equally, the transmission capacity for HVDC offshore connections quadrupled in the last 10 years, now with two gigawatts of transmission capacity for the latest HVDC connections.
And you can do the math, how many of those turbines and HVDC connections we need when we want to reach the official EU targets for offshore power. So this is 60 gigawatts of power in 2030, and 300 gigawatts in 2050.
And therefore, I have to say, honestly, we can't do it alone. We can't do it alone as a single company because it's a joint effort to become net zero and master of the energy transition. It's actually about the whole energy community, and not about the energy, but the whole industry community.
And we can't do it alone as a team. So we need more motivated engineers to join the energy transition and rethink how we produce and consume energy. Because at the end, it boils down to the question, what can your company, and more importantly, you do, to help reach the target of becoming net zero?
And with that question in mind, thank you very much for having me today.
[AUDIO LOGO]