The Siemens plant in Amberg, Germany – a technologically state-of-the-art production facility – will become climate-neutral by 2030. Simulation algorithms that model a location’s complex interrelationships are calculating the most efficient and economical path to decarbonization.
Tomorrow’s world must be carbon-neutral, without fossil fuels or nuclear energy but with renewable energies. Admittedly, the process of making a factory, city, or country carbon-neutral is costly and time-consuming. “Sufficient energy must be available at all times, including during the conversion phase when the infrastructure is being adapted. At the same time, competitiveness has to be maintained or – even better – boosted,” says Franz Mende, Plant Manager at the Siemens plant in Amberg, Germany. “We’ve been gradually improving our energy efficiency over a period of many years, but carbon-neutrality poses a much greater challenge. It’s a matter of taking the right steps in the right order. That’s more complicated than it sounds at first, which is why we’ve worked with colleagues from Siemens Smart Infrastructure, Real Estate, and Technology Business Units as well as with OTH Amberg-Weiden to calculate our path to decarbonization.”
Ambitious goal in Amberg
The Amberg location is one of Siemens’ most advanced sites. Two separate factories – the Electronics Works and the Equipment Manufacturing Plant – develop and manufacture products for the global market that range from the SIMATIC controller to industrial controls like SIRIUS. Customers and partners are offered an inside view at the “The Impulse” Visitor Center opened in 2021, where digital technologies, concepts, and automation solutions for the autonomous factory are developed and presented.
The goal of the Amberg location is to become carbon-neutral within a period of 9 years, starting from 2021. This means converting from fossil fuels to sustainable energy. Because the plant already exists, it’s what experts call a brownfield plant. This makes it especially challenging because the energy transition can’t be allowed to interfere with ongoing operation and productivity.
Amberg is no novice when it comes to saving energy. Energy-efficiency measures were implemented here as early as 2004 with the introduction of Energy Analytics for acquiring energy data, the introduction of energy management according to DIN ISO 50001, the commissioning of two combined heat and power plants, the procurement of green electricity from hydropower, and the introduction of eChillers. The successes are clearly measurable and Amberg is thus making a significant contribution to Siemens' decarbonization success. By 2020, the CO2 emissions of the global factory locations could already be reduced by around 50%. By 2020, carbon emissions had already been reduced by about 50 percent.
Looking a few years into the future – risk-free
“Factors like geographical features, energy prices, a plant’s special characteristics, and much more determine the best path in each individual case,” explains Martin Kautz from Siemens Technology. “Wrong decisions can be expensive or can endanger the project’s success. We’ve developed a software solution for simulating the dimensioning and optimal operation of these multimodal energy systems, meaning environments in which multiple types of energy interact. It allows us years in advance to estimate what will happen under specific conditions if we change something in this energy system. We use this as a basis for calculating the optimal decarbonization path from both a technological and an economic perspective. The method can be applied to entire regions such as a city or, as in this case, to individual plants.”
The green digital twin
In the first step, Kautz and his colleagues analyze the actual state of the electrical, heating, and cooling system and replicate it as a mathematical model known as a digital twin. “The quality of the digital twin determines how realistic the results of the simulation will subsequently be. It’s particularly important that we have precise knowledge of the relevant details of the plant and the products manufactured there,” explains Kautz. “For example, if specific furnaces in a plant have to be operated with gas, this has to be included in the decarbonization path and also defined in the digital twin. That’s why we work very closely with experts on site when doing the modeling – in this case, with Siemens colleagues in Amberg.”
“It’s very often the case that we can already save energy by using the digital twin to analyze and improve the actual state of process sequences. For example, we’re able to find situations where heating and cooling systems are counteracting one another,” says Kautz. “Although this example may sound trivial, these types of process deficit are easily overlooked without a detailed analysis like that required for the simulation.”
Capturing all energy transition scenarios
Process optimization is the first step. Afterwards, the simulation calculates the feasible and affordable technological changes that will make the plant carbon-neutral. “We supplement our digital twin with all the renewable energy sources that are possible for us,” says Kautz. “For example, one such measure would be to equip the entire roof with a photovoltaic system. In the model, we then record how much this type of system costs, how quickly it can be implemented, and how much power we expect. The sequence of measures representing the most economical way to make the plant carbon-neutral is then calculated in the simulation.” For the Amberg location, for example, the greatest carbon reduction potential can be achieved by building a PV system with a heat pump.
Often, the key figures relating to the measures – such as energy prices several years from now or the development of the carbon levy – can only be estimated. “We design various scenarios that represent how energy prices, for example, will evolve and simulate them separately. It goes very quickly, we just need to adapt a few of the digital twin’s parameters,” says Kautz. “This gives us multiple paths to decarbonization that are each optimal under certain conditions. Location management can then decide which scenario they think is the most probable and which path they want to follow.”
But this process doesn’t end with the digital twin. After the first implementation measures have been taken and during the initial years of operation, it’s easy to update the digital twin again and again and constantly recheck the path’s validity.
Amberg’s path to decarbonization
The plant in Amberg, which released about 6.8 tons of CO2 during the 2018/2019 reference fiscal year, is now on a gradual path to decarbonization. “In the first step, we concentrated on individual measures, examining the cost-effectiveness of each one, in order to improve our carbon footprint. We energetically optimized our sequences and now purchase green – meaning carbon-neutral – energy from our electricity provider,” explains Mende. “For our next step towards carbon neutrality, we’ve chosen a comprehensive and agile approach. It’s important that we constantly adapt to changing framework conditions. Among other things, we’re planning on equipping large sections of the roofs with photovoltaic systems. Although that doesn’t further improve our carbon footprint – less than zero is still zero – the power supply system will be cheaper and we’ll be less dependent. That’s why we’d rather prefer a PPA (Power Purchasing Agreement), ideally with a local operator.”
In addition, a heat pump will replace the gas heating in the next few years and will be made as efficient as possible through its clever combination with the cooling system. However, Amberg can’t do without gas altogether because it needs annealing furnaces for the treatment of metal parts. These ovens which will continue to operate for some years to come. “We’re planning on switching from natural gas to biomethane while also investigating the extent to which we can replace natural gas with hydrogen. We’re expecting our operations to be totally carbon-neutral by 2030 without having to buy flexibility by purchasing emissions certificates,” says Mende.
The Siemens Carbon Neutral Program
Amberg isn’t an isolated case. Some 50 Siemens factories are currently working on becoming carbon-neutral within the next few years, including production facilities in the U.S., Canada, Europe, India, and China. These future “green factories” will do more than just implement efficiency measures. Besides the possibility of a standardized procedure, the Siemens carbon neutral program also offers new financing models, the electrification of production, the purchase of green energy, and the introduction of new business models. The influence of political framework conditions is also taken into account, including carbon certificates and their pricing, subsidy legislation, and the taxation of renewable energy sources.