| Title | Update (Geo-) Thermal Smart Grid Mijnwater Heerlen |
|---|---|
| Authors | Verhoeven, R; Eijdems, H; Wenmeckers, M; Harcouët-Menou, V |
| Year | 2016 |
| Conference | European Geothermal Congress |
| Keywords | Geothermal, mine water, smart thermal grid, energy storage |
| Abstract | The Mijnwater system was built up in several stages. In the period 2004 - 2008 (under the Interreg demonstration programme) the system (Minewater 1.0) was designed as a traditional unilateral network with a simple change-over system for heat and cold supply, the underground mine water reservoir purely was used as a geothermal source with limited capacity and Mijnwater acting solely as owner and operator of the grid. After expanding, and due to the need to green the concept, the mine water system was transformed in the period 2012 – 2013 into a thermal smart grid (Minewater 2.0). This consisted of a bilateral cloud structure and cluster grids for instant exchange of heat and cold between buildings. The demand driven grid has 3 levels of control (building/cluster/minewater) with all-electric energy stations (heat pumps) located within the buildings. The new 2.0 system is suited for the implementation of multiple green energy sources and the mine water reservoir evolved to be utilised as an energy buffer. Mijnwater has become a (publicly owned) private company optimizing the business case, maintenance and operation and aiming for ownership and operation of the energy stations (heat pumps) in the buildings. Mijnwater developed a blue print for the overall Mijnwater 2.0 system based on an integral approach from mine water wells and grids to the energy stations and the heating and cooling systems in the buildings. The Mijnwater system is moving towards a ‘demand and supply controlled system’ (Mijnwater 3.0). Based on smart storage and an intelligent top level control frame-work for operational management (predictive and adaptive), with multiple control strategies. Currently, 175,000 m2 of building floor area are connected to the grid, expanding to 500,000 m2 in 2017 and 30 million euros have been invested to date. Energy contracts are closed for more than 300 dwellings, a college, a hotel, a sporting centre and several office buildings, one of which hosts a datacentre. New elements are developed or under development: Smart bi-directional mine water wells; Smart hybrid energy stations; Smart storage - Energy Carrousel; Smart local area grids for existing dwellings. In general the Mijnwater 2.0 system works very well as designed. Some parts operate even better than expected. Others initially failed during commissioning and needed improvement and/or mitigation. The following cases and lessons learned are being discussed: Production wells: Tuning productions wells and cluster installations; Failure membranes pressurized buffers; Leakage incident cold production well; Behaviour cluster grid as a buffer; Hidden defects in system; Bio-fouling cluster grid A. In the past 3 years the performance of the system was monitored which led to new insides and (proposals for) improvements. The following cases and lessons learned are being discussed: Performance network; Performance energy stations APG Pension Fund and Central Bureau of Statistics (CBS); Modification of minewater (exchange) installations in the buildings. |