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During the last years of the 18th century a need to use electrical energy for lighting as it was practised in metropolitan areas also arose in Tallinn. In particular, the safe and efficient lighting method attracted the attention of the business owners operating in the heart of the city. In the beginning of 1909 the Tallinn City Administration decided to build a new power plant on the expense of the city. The plant was to be built on the land located by the gas plant close to the Great Coastal Gate. Closeness of the port and sea favoured supply of coal from England to be used as fuel. However the power plant project, which had started so spectacularly, was stopped because of lack of funding, until 1911 when a contract was signed with the joint stock company Volta. The construction work of the new power plant and grid began in May 1912 and ended in December of that year.
The building of the plant was built according to the design by an architect H. Schmidt. According to the initial design 26 transformer substations with 3 kV high-voltage and 220 V low-voltage cable networks were built. As propelling units three Laval-type 250 horsepower (184 kW) steam turbines made by a local company Volta were chosen. These were connected to 166 kW AC alternators. Two Steinmüller’s coal-fired steam boilers with steam parameters of 12.5 atm and steam superheating up to 325 degrees were installed in the boiler house. The speed of the turbine-generators was 3000 rpm producing three-phase current with a voltage of 3.150 V. At the same time cable lines and transformer substations were built in the city to transmit electrical current to the consumers. Now, when a new miracle solution was found, candles, gas and oil lamps were discarded forever.
The first electricity consumer was connected to the grid on 24 March 1913. This date can be considered as the start date of operation of Tallinn’s electricity grid. The plant was completed for summer 1913 and with the cable infrastructure for electricity it cost 385,000 roubles. The operation of the plant was subject to the control of the lighting and water supply commission of the Tallinn City Council and it was named as the Central Power Plant of Tallinn City. The council invited engineer Evald Maltenek, who had a polytechnic diploma from Riga and whose diploma work was precisely the design of the power plant, to be the manager of the plant. Many former sailors were hired as employees.
The electricity network was built up till the city centre and from there towards the main streets. On Paldiski Road it reached the railway, on Pärnu Road the present Liivalaia Street, on Tartu Road the Central Market and on Narva Road the former narrow-track railway. High-voltage current was directed to the city via three underground trunk lines and in the city it was transformed into 220 V current. This low-voltage current was directed in the buildings. The length of the high-voltage cable (3 kV) was 8.985 m and of the low-voltage cable 9.775 m. In total 24 kiosk-type transformers with a total capacity of 525 kV * A were built. Initially there was a lack of subscribers and their electricity consumption was so small that in the first half of 1913 the equipment of the plant was operating almost without load. By the end of the year the length of high-voltage cables reached 17,009 m and low-voltage cables reached 18,512 m. The number of subscribers had risen up to 754 but as salaries were high and the plant output was only 414,431 kWh, the year ended with a loss of 31 roubles and 45 kopeks.
In 1914 the plant’s director engineer Maltenek proposed to expand the plant. The project received the approval of the council on 16 September, 1915, but expansion of the power station was prevented by the outbreak of the First World War and constant lack of money the city authorities were facing. Nevertheless, more and more consumers were switched in the network and by 1917 the capacity was exhausted. Consumption had to be limited in the whole city. Each subscriber was allowed to burn a maximum of two lamps at a time and sometimes automatic current limiters were used. Difficulties with fuel arose. Anthracite from Donetsk used so far was replaced with wood and turf. The capacity deficiency was eliminated in 1921 by installing a new turbo generator in the power plant of the city. This in turn opened new opportunities for expanding the grid.
On 24 February 1918, when the Russian army left, a major collision between the 1st division of the Defence Forces and the employees of the power plant on one side and soldiers of the Red Army plundering the city on another side. The soldiers of the Red Army, whose aim was to demolish the power plant, were beaten back but during this Johann Muischnek, a member of the Defence Forces, was killed. To honour him a memorial plaque was placed on the tower of the Coastal Gate.
The director of the plant was now of Alexander Markson, who held this position till 1941. By 1918 the load of the Tallinn Power Plant had grown to the extent that the equipment worked overloaded and during evening peak hours help from industrial power stations was used. It was only at the time of the War of Independence in 1919 that the opportunity to increase the capacity of the plant opened up. For this boilers from an English company Babcock & Wilcox were used, a turbo unit with Wumag 2 MW turbine was ordered from Siemens-Schuckert plant and two inclined water tube boilers with the heating surface of 251 m2, steam parameters 15 at 350°C and output of 5 t / h ordered from Steinmüller plant were commissioned in 1921. As fuel, turf was used.
Assembly of the turbo unit was completed in December 1920 and in January next year, the plant supplied alone the city with electricity and thus starting from 1913 the smaller plants, which had been working nonstop so far, could be placed in reserve. The new turbo dynamo used less steam and saved almost 50% of fuel.
By 1922 the load of the power plant had increased by almost double and the output of the plant tended not to be sufficient again. The same year electricity was first used to power also the street lighting in Tallinn. Street lighting points were built and maintained by the power plant. The power plant and gas plant had constant problems with fuel, due to which the lighting and water supply commission turned to the suppliers to obtain more wood.
By 1 January, 1923 the power plant had over 7000 subscribers. The length of the power grid had increased and was now almost 90 kilometres. Around 75% of the production of the plant was used for lighting and 25% for industrial needs. In 1923 maximum load of 1.850 kW was registered.
On 2 May, 1924, a plan of the lighting and water supply committee was approved, according to which oil shale was implemented as fuel in the plant. It was assessed that the general cost for implementation was 54 million marks. The same year grade I and II oil shale was implemented. New 2000 and 1240 kv A turbo units and two Babcock & Wilcox boilers with steam parameters of 15 at 360°C and fuelled by oil shale were set up. Implementation of oil shale was a breakthrough movement at that time. This solved the fuel supply of the power plant for a long time and secondly gave impetus to the development of oil shale combustion technology in Estonia. In 1925 the plant was renamed as Tallinn City Power Plant. By this time the maximum load was 2700 kW.
In connection with implementation of oil shale a number of problems emerged. The plans looked great on paper but the stark reality was something totally different. While burning oil shale, black smoke started emitting from the chimney, wind carried it to the city and this upset people a lot. The smoke war began, which like any other military action, was willingly and thoroughly reflected by the press. It came out that the new metal chimney installed on oil shale boilers was too low, just 20 meters high. At the time the boiler was ordered, the length of the chimney was determined incorrectly, and there was also no experience in burning oil shale in large boilers and it was not possible to find a suitable type of furnace.
Another concern was related to storing ash. Compared to previous fuels, combustion of oil shale generated much more ash but there was not sufficiently space to store it next to the power plant. This provoked the outrage of inhabitants of the surrounding as well as industrial companies. The situation was solved so that ash was carried to the nearby beach, which in its turn increased the area of wetlands. To that end, on 4 February, 1926 a new 250 m long cableway was implemented, along which the workers could push ash carriages back and forth between the plant and the beach. The task of the cableway was to supply steam boilers with fuel and to carry ash and slag from the furnaces to the single-track cable railway located on the beach.
In the 1920s and 1930s, the capacity of the power plants exceeded significantly the load. There was a need to expand the number of consumers. On 15 December Tallinn Power Plant opened a sales point of electrical equipment and a consultancy bureau in the old weighing point at the Town Hall, the main aim of which was to promote domestic consumption of electricity in households. In order to increase electricity consumption, power tools were borrowed to the residents, as the purchase price of the tools was quite high for people not so prosperous. Much attention was paid to making cheap power steam locks, which takes only some minutes, as they say. In the beginning of the 1930s the use of electricity in households expanded even more. In 1936 the first building with 15 electrical kitchens was built in Tallinn. On 1 April, 1939 there were already 29 houses with in total 384 electric cookers with a general output of 1993 kW. An advice centre of the power plant was also opened.
The growing number of consumers led to continuous expansion plans of the plant. In February 1927 director A. Markson proposed to expand the power plant. The council approved the proposal, and thereafter an expansion plan had to be elaborated. For this 300,000 marks were allocated. The reason the plant was expanded in stages was mostly lack of money affecting the city but also lack of experience in this field.
In 1929 the company started assembling a Wumag 5 MW turbine. In 1934 a new boiler house was built and two Babcock & Wilcock boilers with a steam output of 15 t / h with steam parameters 26.25 at 400°C were assembled. At the same time they started using grade III oil shale and for this the furnaces were equipped with AS Ilmarine bar grates. In connection with expansion plans, secondary relays were introduced in the Tallinn Power Plant in 1930. The generators, as well as 3 kV feeders were equipped with current-related delayed overcurrent protection. As a source of operative voltage, a battery (200 V, 240 A * h) was used. Power switches were remote controlled. New boilers were implemented on 11 January, 1935. The boiler house had cost 1,486,476 euros. Now it was possible to implement 5 MW turbine at atmospheric pressure.
By the end of 1937, the total length of the grid had already reached 330 km, of which 82 km were high-voltage grids. By that time there were 44,173 consumers and the general maximum operative load was 7250 kW. Electricity tariffs were thoroughly restructured. 13 different types of general tariffs were elaborated in order to ensure better adaption to specific circumstances. The new tariffs consisted of a kilowatt-hour price and basic fee corresponding to the capacity fee, allowing customers to benefit from the nature and time of power consumption. As to the main fee, the price of electricity used for household and lighting apartments was 6 cents/kWh.
Until 1940 the plant was expanded on four occasions, the author of the three expansion designs was A. Markson, a long-time (1917-1941) manager of the power plant and a qualified electrical engineer. In 1938 the plant became 25 years old. At that time the biggest turbo unit (10 MW) made by Wumag was installed. It required 45 t of steam per hour to work in full capacity. For this they needed a new boiler, which was ordered in cooperation of two companies. By 1938 the electrical capacity of the power plant increased to 19,200 kW being the largest in Estonia at that time. In 1939 a big boiler from the company Babcock & Wilcox arrived. The steam capacity of it was 30 t/h. In addition to the original brick chimney two metal chimneys were built. By the end of the expansion activities in the end of 1939, the capacity of the power plant was 19 MW, which was the biggest at that time. In 1940 a record amount of electricity (38.1 GW/h) was produced.
As a result of the abovementioned expansions, the Tallinn Power Plant became the most advanced and powerful (19 MW) energy company from a technical point. On 20 March, 1940 the plant had achieved such a capacity that anyone interested could be provided with electricity. The power plant was able to keep the rated frequency of 50 Hz so accurately that power meters with a synchronous motor were taken into extensive use. The power of the plant reached 19 MW but the management found it necessary to prepare a development plan for a longer period. This plan consisted of three stages, upon completion of which by 1951 the total capacity had to reach 70 MW. However due to the war conditions, the expansion plans were left aside.
In 1940-1941 the power plant fell into the hands of new power. Jaan Kilter was appointed plant director. He joined the people’s commissariat of the power plants in Moscow. The power plant had to demonstrate its boundless loyalty to the new power. To this end, meetings were convened, which were organized during red holidays and events.
Starting from 1 November, 1940, the power plant was subjected to the power of the power and heat management section of the community amenity of the executive committee of the council of the workers deputies of the Tallinn City. On 18 March, 1941 a power, gas and water supply trust of Tallinn City was formed within the power and heat management department. Everything started to be organised by the primary organisation of the Communist Party. During the parade of the October Revolution Day slogans such as “We increase power energy production at the Bolshevik pace”. The development plan of expanding the power plant was interrupted by the outbreak of the war.