Hybrid and gravity renewable energy centers, energy storage in compressed gases in idle mines, and innovative technologies for batteries and charging systems for mining vehicles – these are some of the most interesting projects presented during the annual scientific and technical conference KOMTECH in Szczyrk (11-13 October 2021).
Experiments conducted at the KOMAG Institute have shown that an example prosumers using solar energy can consume from 23 per cent of the energy produced on a sunny weekday, to 97 per cent on a cloudy day off, when the household uses more electrical appliances. This means that practically all the time the solar panels are in operation, surplus energy is obtained, but if there is no possibility of storing it, the prosumer has to draw and buy electricity from the power grid during the night hours.
For such users, scientists from KOMAG developed a concept of hybrid energy storage, consisting of three modules: short-term storage in the form of supercapacitors, lithium batteries storing energy in the medium term, and long-term storage, using hydrogen technology.
“Such a solution, with proper optimization, can provide prosumers with complete energy independence, and also contribute to the stabilization of the national power grid,” said Piotr Hylla of the KOMAG Research Institute.
The results of research work on energy storage in compressed gases using post-mining infrastructure were presented by Łukasz Bartela of the Silesian University of Technology. “We hypothesized that some of the post-mining underground workings can be successfully adapted for the storage of gases acting as energy carriers – in particular, compressed air and compressed carbon dioxide,” said Łukasz Bartela.
According to him, such energy storage systems in mine shafts could be competitive with other large-scale energy storage technologies in the future.
“We are talking about energy capacities even above 100 MWh while maintaining the power at the level of 10 MW,” said the scientist from the Silesian University of Technology. Scientists from the Silesian University of Technology have been focusing for several years on the possibility of using not entire excavations, but mine shafts themselves, which “are hollowed out in the protective pillar and are inherently tight”.
During the KOMTECH conference, an innovative battery power supply system for self-propelled shooting trucks was also presented, which has already been implemented in copper ore mines belonging to KGHM. The system developed by KOMAG researchers is currently produced and installed in mining trucks by KGHM ZANAM plants in Polkowice.
The new solution has already been used in the Sieroszowice, Lubin, and Rudna mines. It is designed to power a pumping device for explosive material in various size coalfaces. The new system avoids the need for haulers to travel to the charging station, as it is now sufficient to connect the battery system, based on lithium cells, directly to any switchgear of the mine’s 500V power grid.
“As a result of the implementation, not only has greater comfort and safety been ensured for the vehicle operator and blasting miners, but also the time previously wasted on uncoiling and coiling the supply cable has been saved,” Przemysław Deja of KOMAG said during the system presentation.
He pointed out that a full charge of the batteries allows the truck to operate for up to four work shifts, which makes it possible to arm about 16 faces.
During the KOMTECH conference in Szczyrk, the concept of creating gravitational energy storage facilities on post-mining areas in Silesia was also discussed. using technology from the British company GRAVITRICITY. Kamil Talar from the NRG Project presented operation modes of energy storage supporting green energy transition in Poland.
The results of many detailed studies were also presented, including the influence of balancing systems on voltage and temperature changes of lithium cells in a battery controlled by BMS (Wojciech Kurpiel, KOMAG) and the effectiveness of detection methods of voltage decay in the mains (LoM) for power generation devices (Andrzej Niedworok, KOMAG).
During the KOMTECH conference, in addition to 9 papers related to green energy, two discussion panels on the energy transformation of Silesia were held and a workshop on renewable energy sources for representatives of local governments was conducted.