Lignite, often referred to as brown coal, is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat at shallow depths and temperatures lower than 100 °C. Lignite is mined all around the world and is used almost exclusively as a fuel for steam-electric power generation.[1] Most lignites are geologically young, generally having formed during the Mesozoic and Cenozoic eras (approximately 251 million years ago to the present). Many lignite beds lie close to the surface and are of great thickness, sometimes greater than 30 m (about 100 feet); they are easily worked, and the cost of production is low. It is considered the lowest rank of coal due to its very high amount of moisture and relatively low heat content.[3] Upon exposure and weathering, some of its water is given up, and disintegration, or crumbling, of the material occurs, which reduces the value of lignite as a fuel. Lignite also tends to disintegrate during combustion, and hence the losses through a grate may be relatively high. It requires special care in storing, is uneconomical to transport over long distances, and is subject to spontaneous combustion. The fuel is used primarily by local utilities and industries and by domestic consumers close to the mine sites. It has been estimated that nearly half of the world’s total proven coal reserves are made up of lignite and subbituminous coal, but lignite has not been exploited to any great extent, because it is inferior to higher-rank coals in calorific value, ease of handling, and storage stability. In areas where other fuels are scarce, the production of brown coal far exceeds that of bituminous coal.[4]

The lignite deposits of Evia, especially those in the wider area that today forms the municipality of Kymi-Aliveri, but also of Karystos, were already known since ancient times. The historian Pausanias mentions the “coal” of Evia, but his contemporaries did not have the know-how or the ability to exploit it. Thus those specific deposits remained essentially unexploited beyond any occasional use by the inhabitants of the surrounding areas.[5]

The Beginnings

The first scientific research regarding lignite began in the area of Kymi in 1830. The first exploitation of a lignite mine began there in 1833 when it was attempted to use lignite in the furnaces of the naval base of Kymi and in the boilers of early steamships. However, organized exploitation began almost forty years later, when in 1873 some private individuals obtained the concession from the state of the right to mine lignite in Aliveri.

The lignite-bearing basin of Aliveri is located 3 kilometers north of the homonymous city, in the area of Prinias next to the village of Agios Loukas. The location of the deposit is peculiar because it is not parallel to the surface of the earth as in other mines, but with a slope, its thickness fluctuates, while its depth below earth surface reaches 200 to 300 meters.

Initially through wells and later through tunnels, the lignite was mined and transported to the port of Karavos by railways and wagons pulled by mules. The first underground operation stopped in 1897 when, due to a great flood, the galleries were filled with sea water and surface facilities were destroyed. With the advent of the First World War in 1914, new energy needs arise leading to a new attempt at exploiting the lignite deposit. But this was a sloppy and predatory effort that caused the deposit a lot of damage.

In 1918, the Aliveri Coal Mining Company was established. The company, which got to be known as the Aliveri Company, purchased ownership of the rights to exploit the lignite deposit. Production started that same year with 12.849 metric tons being mined. In 1927 the financial collapse of the Aliveri Company began, leading to its dissolution and liquidation by 1934. Nevertheless, from 1934 to 1950 production continued without interruption, under the management of the company’s liquidators. During the Second World War years and the period of German occupation, a decrease in production is observed and only in 1949, with the simultaneous improvement of mining methods, an increase in production is achieved for the first time, reaching 25,000 tons per year.

The Era of Electrification

The year 1950 marks a new beginning for the Aliveri lignite mine when it is expropriated in favor of the Greek state and then, from November 1, 1951, in favor of the newly founded Public Power Company – PPC (Greek: Δημόσια Επιχείρηση Ηλεκτρισμού – ΔΕΗ), becoming the supplier of the company’s first steam power plant. On November 9, 1950, a contract was signed between the Greek State and the American company PIERCE MANAGEMENT INC. which would act as the main contractor for the PPC, which in the meantime had undertaken the titanic task of electrifying the entire war-torn country.

The contract provided for the completion of all mechanical installations, the winch and the elevator, the execution of mining works on the surface, the mining of new wells, the construction of new inclined tunnels, as well as all the safety mechanisms that such an underground mining operation requires. On May 19, 1951, another contract was signed between the PPC and the German company PH.HOLZMANN A.G., a subcontractor of PIERCE MANAGEMENT INC. regarding the construction of surface facilities at the Aliveri lignite mine as well as the drilling and mining of 115 meter deep shafts, 1,750 meter long tunnels and an underground pumping station.

The PPC officially took over management of the mine on May 21, 1954. This date marks the beginning of the intensive and systematic exploitation of the lignite deposits of Aliveri, with both underground and surface mining, on an area of approximately 420 acres. Alongside the installation of equipment and machinery and the application of innovative methods and relative technology, unique in Greece at the time, the first electric energy production system of the country was created.

The Operation

The various phases of the lignite production process included excavating and supporting galleries, mining, loading and transporting the mined lignite to its final destination which was the steam generation hearths of the Aliveri Steam Power Plant boilers.

The underground mining method chosen was the sub-level caving method. Storeys were 5 meters high and every 30 meters there was a floor which included 6 storeys. Lignite was mined from the bottom up. The galleries, totaling 880 meters in length, were lined with concrete and were used to move underground railway trains and personnel to the deposit which was 220 meters away.

There were master galleries, whose cross-section was horseshoe-shaped with a diameter of 3.5 meters, from which smaller main galleries branched off towards the deposit. These were the passages for transporting the mined material as well as the necessary air and had a total length of 2,500 meters. Finally, smaller galleries with an inclination of 55 degrees branched off the main galleries, connecting the complex of master and main galleries to the mining levels and extraction fronts.

The lignite mining process involved digging holes with rotating electric drills, charging them with explosives and blasting sewers. This was followed by the transport of lignite from the mining fronts to the inclined levels, first by chain conveyors and then by electric carriages. These carried wagons full of lignite to the lifting cages where an electric winch lifted the mined material to the metal tower and unloaded it.

This was followed by breaking down the mined material and removal of any large foreign matter from the lignite, which was then transported by conveyor belt to the storage areas, before being transported to the surface and the cleaner, which belonged to the mine facilities and consisted of a tipping tower for the loaded wagons and a four-story enrichment complex. There the cleaning was carried out by successive processing of the material through vibrating screens, hand sorting, crushers and air separators. Finally, the lignite separated from the sterile material was sent to the braker and from there, either to the open-air warehouse or directly for burning at the Aliveri Steam Power Plant.

Also part of the mine facilities were two high steel towers above the two shafts of the mine, with winches for lifting and descending cages to a depth of 192 meters, industrial sheds housing electromechanical equipment that supported the mining activities, specialized buildings and constructions for the servicing the workers, changing rooms with individual storage for the technical clothes of the miners and, finally, a warehouse of materials and tools for the loggers working in the underground galleries. Of the steel towers, one was for ventilation and staff ascent and descent and the other was for lifting lignite from the galleries.

Ventilation of the underground galleries was ensured by two very powerful industrial fans installed on the surface. These drew air from even the smallest and most remote gallery and created a circuit of fresh air supply down to the mining fronts where the miners worked. Special technical clothing, insulating and protective helmets and powerful lights accompanied them in their work deep under the earth surface. The lights were mounted on their helmets and had batteries that lasted eight hours, the duration of their shift. In 1955, when the mine was in full operation, it employed approximately 1,300 workers. Of these, 900 worked in the underground operation and the rest on the surface.

Underground operations and mining of lignite stopped in 1981, and a little later, in 1988, the surface exploitation that had started in 1975 also ended. During its years of operation, it is estimated that a total of 14.7 million tons of lignite were mined from the underground works of the mine, while 3.9 million tons were gathered from the surface operation.

During the years the mine was operational the town of Aliveri showed great economic growth and prospered as, apart from PPC, side industries or crafts were established in the area, as well as AGET Iraklis which established its own cement factory next to the PPC power plant. For 35 whole years – until 1988 – the Aliveri Lignite Mine was a center of economic development and progress for the residents of the wider area.

The Present

Today the site of the old lignite mine houses the PPC’s Metal Constructions Unit as well as a small museum which, however, does not operate. On their own initiative, employees of the Metal Construction Unit have reconstructed one of the JUNG locomotives from 1957, which is currently on display in Ptolemaida, a lignite transport wagon, a tank and the chamber that raised and lowered the lignite miners to the galleries. The second JUNG locomotive has been donated by the PPC to the municipality of Aliveri, but this remains on site and rusts. The small settlement next to the lignite mine has been practically abandoned as few families still remain in it today.

The Jung locomotives were the first to be delivered by the German company PH.HOLZMANN A.G., as part of the 1951 agreement was the construction of a 22 km long railway line connecting Prinias to the power plant in Karavos in Aliveri. The railway was used to transport lignite from the mine to the plant and ash back to the special deposit site in the mine. In 1968 those locomotives were replaced by Japanese and German diesel locomotives. Some of them are still at the mine site while one is still operating on the railway network of Thessaly. Today the only remaining part of the railway line lies in the “Steno” area of Aliveri as the ring road constructed after the mine ceased its operation was designed to pass through the segment of the railway where there was a double track.

The two lignite units of the Aliveri Steam Power Plant, as well as two newer units operating on fuel oil, have been decommissioned since 2007 and remain in cold reserve today. Despite this, Aliveri remains an important energy hub for Greece and the Aliveri Steam Power Plant continues its operation. In 2012 the natural gas powered Unit 5, with a total capacity of 420MW, went into production. At the same time the whole region of ​​Central and Southern Evia is morphologically and climatically favorable to the development of wind farms which channel the generated energy into the national grid through the Aliveri hub. Finally, Aliveri is a main hub for the project interconnecting the Cyclades and other Aegean islands with the continental electrical supply grid that is currently being implemented.