100 % renewable energy through Power-to-Gas
The research network "100% EE durch PtG" analyses the potential and applicability of the Power-to-Gas (PtG) process in the German Energiewende. A research consortium studied the potential and suitability of PtG. The researchers test how a 100 percent supply can actually look like from renewable energies and what requirements arise for a future energy supply system, including the PtG technology study.
|Project status||Demonstration phase|
|Project duration||November 2012 until April 2015|
In order to fit an actual load curve for a supply solely through renewable energies, a next generation technology with a much higher capacity and duration of energy storage than the current availiable is needed. The Power-to-Gas technology produces substitute natural gas (SNG) using electrical energy. This SNG can be retransformed if needed. For the design of a decentralised region with a 100% supply through renewable energy and the demonstration in the field, the focus is put on PtG as an energy storage. This includes concretisation and quantification of technical and economical requirements for PtG as an energy storage, as well as the demonstration of the technical feasibility and the constraints of a 100% renewable energy system using PtG.
Stabilize the grid
In terms of a changing energy supply to a system of 100% renewable energy, the relative share of volatile renewable energies (wind power and photovoltaics) in the power network will increase significantly. This will pose new challenges to the system of power supply and distribution networks. On the one hand the grid stability has to be ensured, on the other hand actions have to be taken to enable high proportions of volatile renewable energies in the energy mix in order to compensate a mismatch of power supply and demand, i.e. balancing chronologically excesses and deficits of consumption and demand. This leads to an increased demand for long term energy storage plants for potential high amounts of energy, which can maintain the energy for weeks or maybe even several weeks or months with relatively small stand-by losses. One possibility to meet these requirements is the PtG technology, which stores the power chemically bound in form of methane.
The main requirement from the systematic point of view is a dynamic operation to balance the volatile energy production and its checkability. At the same time the PtG should be compatible to the peripheral devices especially the substantially connected ones like renewable CO2 sources or the gas distribution system concerning quality and pressure of the gas. Another challenge is the profitable operation in context of few full-load hours because of the balancing mode.
Simulation and optimization
Objectives of the project are concretisation and quantification of the technical and economical specifications of the PtG technology for the intended purpose and practical demonstration of the technical feasibility or rather the constraints of a 100% renewable powered system by PtG as a storage system. In addition to the complete simulation and optimisation of the examined region using PtG, the knowledge of the specifications will be expanded by the experiences through the demonstration stage. This assists to reach an outstanding level in oder to evaluate the technology relating to its potentials and limits, as well as the technological requirements and developments needed.
The project consists of two chronologically seperate steps, currently working on the first step:
First Step: conception stage: definition of the model region, estimation of PtG's potential for this region, simulation and optimisation of a supply solely through renewables as well as analysis and evaluation of its results. These conclusions are used in the demonstration stage to define the specifications for the PtG system. The first step will be finished in February 2014 and is split into the following working packages: 1. estimation of the PtG technology's potential for the model region, 2. evaluation of simulation and database requirements, 3. programming of the simulation model , 4. execution of the simulation , 5. simulation evaluation, 6. capability test.
Second Step: demonstration stage: Verification and optimisation of the simulation's results by conducting a field test. The following working packages are planned for stage 2: 7. design and construction of a PtG plant and its optimisation, 8. embedding into the energy landscape, 9. operation and demonstration, 10. analysis
Technical and economical specifications
This project's overall aim is the systemic design and practical demonstration of the energy supply for a region consisting of 100% renewable energy. The focus is set on Power-to-Gas (PtG) technology as an energy storage system.
Objectives of the project are concretisation and quantification of the technical and economic specifications of the PtG technology for the intended purpose and practical demonstration of the technical feasibility or rather the constraints of a 100% renewable powered system by PtG as a storage system.
Demonstration prove its practical suitability
A specific feature of this project is the demonstration and practical application of the concept designed in the first stage. For this purpose a PtG plant is designed and build according to the hardware- and software specifications determined in the first stage. This PtG plant will have a technology, which is especially designed for a realistic environment with high feed in of renewable energies for the first time. In the demonstration phase a lot of experience is gained, which helps to reach an outstanding level in order to evaluate the technology relating to its potentials and limits, as well as the technological requirements and development needed.
Based on the developed specifications a simulation model is created. For the defined scenarios a simulation and optimisation of a 100% renewable powered supply system is carried out.
Economically efficient operation
The aim is the concretisation and quantification of the PtG technology's technical and economical requirements as an energy storage system. Within the framework of the project, economic parameters are gathered and, assists by the simulation, specifications are gained. These results are verified in the demonstration stage. The economical requirement is a profitable operation of the plant in context of the realisable operation grade.