“ How can we achieve a balance between the generation and consumption of electricity in the future? This is the question that motivates my work, which is why I am searching for smart solutions for energy storage. I investigate all possibilities, from car batteries through to natural gas grids. ”
Dr Jens Kanacher is our expert for Systems Analysis and Storage
Energy systems and storage
The sun, wind and other renewables are playing an increasingly important role as sources of energy. Our energy systems need to become more flexible as renewables generate an increasing share of our electricity. This means that powerful storage systems are becoming increasingly crucial.
Renewable energy sources not only protect the environment, they also call for completely new, smart solutions. While solar power systems and wind turbines can already meet all of Germany’s energy needs on sunny and stormy days, these systems only produce a fraction of the required power if the sky is cloudy and the weather is calm.
This is why innogy is examining the exact changes that are needed to facilitate the energy transition and determining the specific requirements that energy storage systems need to meet. These storage systems need to precisely adapt to specific requirements and play very different roles on a case-by-case basis.
innogy is conducting research to find out what the ideal combination of features is for storage systems, as part of the ‘Energy systems and storage’ project. We investigate a large range of systems, from single-family houses through to the nationwide energy system in Germany. We run computer simulations to determine, for example, where it would be useful to deploy energy storage systems and what features these systems should have. innogy frequently implements such projects to investigate specific questions relating to energy storage.
We need to consider the bigger picture relating to energy systems in order to create smart solutions for the energy transition. We need to determine how we can effectively network different application areas that require energy, such as lighting, heating, transport and industry. This approach is called ‘sector coupling’, and involves, for example, using electric cars for power storage or reusing waste heat to supply heat.
Sometimes too much, sometimes too little.
Solar power systems and wind turbines sometimes produce more electricity than is required at the time, and sometimes less, depending on the weather conditions. We will need many smart storage systems in the future in order to align generation with consumption.
“Imagine it were possible to not only use solar power generated in your local region, but to store this power temporarily. This energy could then be used later, for example, to charge electric vehicles. Wouldn’t that be great ?”
Dr Stefan Nykamp works for Westnetz, a subsidiary of innogy, on grid storage systems and grid innovations
greenfuel. The energy transition is going very well in some fields. For example, there has been great progress with energy-efficient LEDs, electric vehicles and renewable electricity. However, we still depend on conventional fuels in other areas, for example, when transporting goods by either sea or air. We need high-density storage systems for green electricity in order to significantly reduce CO2 emissions that are detrimental to the environment.
We developed our greenfuel concept in order to solve this problem. We used green electricity, water and CO2 to create methanol, a ‘green’ liquid energy source with a high energy density. The best part of this solution is that methanol can be produced anywhere in the world where there is a lot of space and a lot of sun or wind. The methanol can then be transported to wherever it is needed.
Our ‘green’ methanol was essentially a mobile storage system for green electricity. The process of converting methanol into electricity only emits as much CO2 as is taken from the air when producing the methanol.
Our vision is for this energy source to complement the direct use of green electricity and make a crucial contribution to phasing out fossil fuels such as coal, oil and natural gas.
We wanted to demonstrate that greenfuel works as part of a project in Essen, the 2017 European Green Capital. This is where we produced methanol at a pilot plant, using water, CO2 from the ambient air and electricity from our hydropower plant at Lake Baldeney. Also to be experienced in 2017 in the City of Essen: The use of sustainably produced methanol in the excursion boat MS innogy as well as in two cars with a hybrid electric and fuel-cell drive.
The cars were also integrated into the energy supply system of a house. The photovoltaic system on the roof charged the car battery or the battery in the basement on very sunny days. If the solar power was not enough to meet the energy needs of the house, the fuel cells of the car supplied energy to the house.
Battery systems. Westnetz, an innogy subsidiary, is testing a special kind of battery system in Wettringen, near Münster, Germany. The system can store an amount of energy that is equivalent to what is stored in around 2,000 car batteries. The battery storage system helps compensate for the fluctuating volume of green electricity that is fed into the grid. There are many photovoltaic systems in the region that produce a large volume of electricity, particularly at midday on sunny days. This energy can now be transferred to the batteries, which means it is no longer necessary to expand the local grid to store surplus power. The energy stored in the batteries can then be fed back into the grid on cloudy days or at times of high demand. Westnetz is drawing on its experiences with the test facility to further improve the economic viability of such storage solutions.
Energy storage in a district. Locally producing, storing and using electricity and heat – Süwag, an innogy subsidiary, has implemented a project in Kelsterbach, Hessen, that demonstrates how an entire residential area can independently meet most of its own energy needs. A co-generation plant, a natural gas boiler and a photovoltaic plant supply electricity and heat to the 180 terraced houses in the area. Any surplus energy generated by the systems is temporarily stored for later use. Two storage systems are on standby, ready to supply heat when necessary, and a battery system can store enough electricity to cover the energy needs of ten four-person households for an entire day. The success of the project demonstrates that a decentralised supply concept can work. On average, the district generates 90 per cent of the electricity and 100 per cent of the heat it requires.