A capacity management and monitoring system for optimising renewable energy and sustainability challenges in the gas distribution grids

The gas distribution sector in the Netherlands is facing several sustainability challenges. The main challenges are reducing methane emissions, connecting a growing number of decentralised, renewable gas producers and changing customer needs from, for example, CNG-filling stations. Together with tight cost reduction targets these changing patterns form a huge challenge for the gas capacity management skills at Liander, a large gas distribution company in the Netherlands. From our perspective, this situation leads to pivotal new functions and innovative solutions in the gas distribution for the energy puzzle of the 21st century. First of all, it will become a necessity to get detailed information on the gas flows. This is done by introducing a gas grid Capacity Management and Monitoring system (CMM-system) that contains near-real time gas balancing information on a 24/7 basis. The CMM-system functions as a day-to-day monitoring tool and provides essential information to optimize the (re)design of the gas distribution grid. Several types of field measurements are needed for the CMM-system to work accurately. The measurement consists of flow, temperature and pressure sensors on all pressure levels of the gas distribution grid. The challenge lies in minimizing the number of measurement points needed to gain the required accuracy in the CMM-system, because the measurement points are costly. To maximize the information obtained by a minimal number of measurements a simulation program called Model Predictive Control (MPC) is being developed. The MPC program simulates the near-real time behaviour of the gas in the distribution grid. Additionally, weather-dependent forecasts up to 3 days ahead can be simulated. The calculated values from the simulation are combined with the field measurements to verify the outcome. Furthermore, the MPC model can be used for the development of consumer profiles by use of data obtained from Smart Metering. All data from the measurements and smart metering will be securely available online for grid operators using the CMM-system via a privately-owned CDMA wireless network. The MPC program combined with the minimized number of measurement points will provide reliable information to enable an effective and efficient CMM-system for the gas distribution grid and enables maximum feed-in of renewable gasses, reducing methane emissions and facilitate more demanding gas consumers.