According to the estimate of the International Energy Agency (IEA), global CO2 emissions in 2020 will drop by 8%, or almost 2.6 gigatons, to the level of about 10 years ago. This is because the coronavirus crisis has directly impacted energy consumption and led to lower emissions. However, as previous crises have shown, when emissions start to rise again, the increase could exceed the decrease, unless the investments being made to revitalize the economy are geared towards making our energy infrastructures friendlier to the environment. So how can we generate electrical power in the future in a way that is reliable and ecologically sound? And what must our drive and propulsion systems run on if they are to deliver power with climate-neutral results? And how can we achieve all of these things with maximum cost-efficiency? There is no single and absolute answer to these questions. What is certain, however, is that a variety of solutions are needed to produce a cumulative effect. Among the most promising are high-capacity batteries, synthetic fuels and the fuel cell.
The moment has come for batteries and fuel cells
Between January and March 2020, more than half of the electrical power generated in Germany came, for the first time, from renewable energies. But electricity generated from wind and solar is naturally dependent on the weather. Achieving a constant and reliable power supply from renewable sources is therefore possible only if they are combined with reliable modules that come onstream immediately whenever they are needed – e.g. when the wind is still, or when it is raining, or if renewable energy cannot be harnessed for a different reason. That is why the hour might now have come for widespread use of batteries and fuel cells as the key to making our energy future clean and secure. “These technologies have long featured on our development road map,” explained Dr Peter Riegger, head of the Rolls-Royce Power Lab, the new division in which all the threads of the company's technological development run together. “We're testing a wide variety of scenarios and application fields,” he said. Batteries and fuel cells present such interesting possibilities because they are capable of interlinking the electrical power, heat and mobility sectors more strongly. Together, these sectors account for almost half of climate-damaging emissions. This 'sector coupling', as it is known in the trade, is a very important aspect of decarbonization.
Wide-ranging portfolio for energy storage
On the Power Systems technology road map, the greatest headway has been made in the field of battery containers. Following the company's acquisition of a majority stake in the start-up enterprise Qinous, several batteries were added to the mtu product portfolio. The company's proprietary microgrid on site in Friedrichshafen, for example, has a battery container with the capacity to store 1 MWh of surplus energy. That provides the flexibility needed to use the different energy sources that the microgrid integrates. The batteries also facilitate a reduction in the amount of time the plant is powered using fossil fuels. Battery technology offers yet another advantage in that it supports frequency and voltage regulation in the power grid.
Demand for flexible technologies
The more renewable energy sources are used however, the more important it is to have flexibility. Besides flexible power systems, load management, network expansion and energy storage, flexible sector coupling with Power-to-X technologies is another major building block. Power-to-X refers to the transformation of surplus electrical power into a different energy carrier. The manufacture of synthetic fuels is a particularly important aspect of sector coupling. “Synthetic fuels from Power-to-X processes offer a climate-neutral alternative to fossil fuels. They have the same calorific value, are simple to store and transport, and make it possible to use existing infrastructures based on diesel engines with climate-neutral results,” explained Dr Daniel Chatterjee, head of the Green and High-Tech program at Rolls-Royce Power Systems.
Rolls-Royce, in cooperation with policymakers, researchers and industry, is supporting research into green fuels in a variety of projects. One such joint enterprise is the settingup of a Power-to-X Center of Excellence in Lusatia in cooperation with the Federal State of Brandenburg, the Brandenburg University of Technology Cottbus-Senftenberg and other companies. Furthermore, Rolls-Royce is currently playing a leading role in the MethQuest project which is being subsidized by the german Federal Ministry for Economic Affairs and Energy (BMWi). The aim is to research into and develop technologies that allow methane to be produced as cost-efficiently as possible using electricity generated with renewable energy. 'Green' methane produced in this way could then be used to fuel power generation systems as well as trains and ships, thereby achieving climate neutrality.
“We’re taking an undogmatic approach to addressing the challenges of the energy turnaround and climate change, and that means we’re open to all technologies”
Fuel cells and the future
In cooperation, amongst others with Daimler, the PowerLab is currently examining the potential of the fuel cell as a climate-neutral source of driving power and energy. Fuel cells could initially be used as a source of energy for data centers, but also as a reliable component in microgrids. A fuel cell prototype is to be integrated into the mtu site in Friedrichshafen in 2020. Implemented in isolation, none of the technologies outlined above will be able to satisfy the world's energy and mobility demands or slow down global warming. The real answer lies in integrated solutions that deploy different technologies in changing combinations. “We’re taking an undogmatic approach to addressing the challenges of the energy turnaround and climate change, and that means we’re open to all technologies,” said Andreas Schell, CEO of Rolls-Royce Power Systems. “And because we're highly committed, we've considerably revved up our activities.”