International. In the coming years, one of the main challenges that cities around the world will face is how to be able to meet the growing increase in energy demand, which is estimated to be 50% higher than the current one in 2030. This, together with the EU's goal of generating energy without fossil fuels in the future and the need to achieve a sustainable energy mix, has led Siemens to develop the most innovative technology to offer solutions to these important challenges.
The increase in the use of renewable sources for electricity generation becomes, therefore, one of the main purposes for countries that intend to achieve these objectives. However, one of its main problems is its unpredictable generation and dependent on weather conditions since, sometimes, it causes thousands of megawatts to be wasted at times of maximum production due to the impossibility of storing it. For this reason, Siemens has focused all its efforts on developing, through a team of experts from its Siemens Corporate Technology division, three new solutions capable of storing surplus energy from wind and solar farms:
Batteries that store large amounts of electricity
One of these innovative storage systems is the one that is carried out through siemens modular batteries called Siestorage. These batteries have the capacity to store large amounts of electricity thanks to the revolutionary Caterva, which allows homes to have solar panel systems and be able to rent them as an electric parking area. In addition, Siestorage is able to act as both an energy producer and a consumer and this combination helps to improve grid stability and allows for greater integration of renewable energy sources into the system.
Transform surplus energy into hydrogen
Another of Siemens' pioneering technologies is capable of producing large amounts of hydrogen from surplus renewable energy from wind and solar farms. This is Silycer 200, a machine that extracts almost pure hydrogen from water and electricity as raw materials, with a very high yield (75%).
This technology works through the PEM electrolysis technique, which uses water, electricity and a proton exchange membrane to store the surplus in the form of hydrogen. In addition, it acts as a regulator of the current so that it remains constant despite sudden changes in water, allowing to improve the performance of the facilities. The proton membrane makes it possible to take advantage of all the energy capacity generated, even at production peaks.
The hydrogen generated from electrolysis can be converted to create heat or it can be electric current by means of a fuel cell. For example, in the near future it will serve to supply hydrogen cell vehicles. Also hydrogen attached to carbon dioxide can give rise to methanol, which could be a clean fuel for use in cars.
Electrolysis also to generate chemicals
Electrolysis also makes it possible to transform surplus renewable energy into heat, fuel and chemicals, such as carbon monoxide. According to Maximilian Fleischer, in charge of chemical storage system developments at Siemens Corporate Technology, "due to their high power density, forms of chemical storage are the best way to achieve the greatest use of surplus electricity." His team works on electrolysis procedures to convert electricity from renewable energy into necessary chemicals, such as carbon monoxide, ethylene or alcohols.
Natural stones to store energy in the form of heat
Finally, Siemens is developing in collaboration with the Hamburg University of Technology and the local energy company Hamburg Energie, a new storage system called future Energy Solution (FES) capable of storing excess energy for several hours or even for an entire day. In this case, the surplus energy is stored in natural stones that store the energy in the form of heat and then transform it back into electricity. The design is simple, cost-effective and can be used as a complement to existing storage systems.
