The Berlin Plant extension operates through an Organic Ranking Cycle bottoming binary unit, using brine from two separator stations.
Verkís services was detail design, tender documents, procurement, commissioning: mechanical and electrical equipment, control and protection.
The plant utilizes 300 kg/s of 180°C geothermal fluid for electrical generation. The brine is extracted from 4 wells, 2.000 to 2.500 m deep and is led through two mist separators. The two fluids coming from the mist separators are not mixed.
The brine is led through evaporators, consisting of two pre-heaters and a re-boiler, and exchanges heat with the plant’s working fluid. Isopentane is used as the working fluid in the Organic Ranking Cycle. It is circulated in a closed loop and is led through the radial inflow turbine to generate electricity. The fluid is then regenerated at the condenser where cooling water is circulated through a wet cooling tower of the counter flow type.
The 13,8kV generator is of the air cooled turbo type, installed with air-to-water heat exchangers. The exciter system is of the brushless design. The generator is connected to a 13,8kV switchgear, which is metal-clad, compartmented and withdrawable. The switchgear is connected to a power transformer, where the second winding is connected to a 115 kV high voltage line through a disconnecting switch to the existing plant substation. The 480V distribution switchgear consists of compartmented withdrawable feeders. The 120V direct current system is redundant.
The control system comprises of one PLC, installed with hot standby CPU units. The control systems are connected to two servers, one located in the binary plant and the other in another existing plant and a connection to a dispatch centre is installed. The protection relay system is of the double digital type, provided with data communication links.
The Challenge
Reykjavík Energy owns the Hellisheidi geothermal power plant, a combined heat and power plant located about 20 km from Reykjavík in south-west Iceland. The area is one of Iceland’s most active high enthalpy areas. A new area, at Gráuhnúkar, is being investigated for steam and fluid extraction. The purpose of the plants is to meet increased demand for electricity for industrial and domestic use and for hot water for heating. The 303 MWe geothermal power plant in Hellisheiði, Iceland, was commissioned in 5 stages during the years 2006-2011. The first stage was completed in 2006 with two high pressure geothermal turbines of 45 MWe capacity each. The second stage was completed in 2007 with one low pressure geothermal turbine of 33 MWe capacity. The third stage was completed in 2008 with two additional high pressure geothermal turbines, 45 MWe each.
In 2010 a heating plant for hot water generation was added to the plant, intended for district heating. The heat output of the first stage is 133 MWth and two further 133 MWth stages are to follow later. At the same time the Hellisheiði hot water main was put into service. The main is a 19,5 km long pipeline, 0,9-1,0 m in diameter, that carries hot water to Reykjavík. In 2011 the 5th stage of the plant was finished, which includes two new 45 MWe high pressure geothermal turbines, similar to the former turbines, situated in a new power house in Sleggjubeinsdalur.
The plant utilizes 500 kg/s of 180°C geothermal steam for electrical generation. The hot fluid is extracted from 30 wells, 2.000 – 3.000 m deep, and is led through steam and mist separators before entering the turbines. The high pressure steam gathering system operates at 9 bara pressure. The low pressure steam is generated with flashing of brine water from the steam separators at a pressure of 2 bara. The generating units are of single flow, single flash type with axial exhaust. Cooling is achieved through wet cooling towers of the counter flow type.
The main components of the electrical system for each unit consist of a 50 MVA generator, 50 MVA step-up transformer to 220 kV transmission voltage, an 11/11 kV transformer for connection to the 11 kV station service system and two 11/0,4 kV transformers for station service. The generating units, as well as the 11 kV and 0,4 kV distribution boards, are monitored and controlled by the state of the art control- and protection equipment.
Our Solution
Reykjavík Energy owns the Hellisheidi geothermal power plant, a combined heat and power plant located about 20 km from Reykjavík in south-west Iceland. The area is one of Iceland’s most active high enthalpy areas. A new area, at Gráuhnúkar, is being investigated for steam and fluid extraction. The purpose of the plants is to meet increased demand for electricity for industrial and domestic use and for hot water for heating. The 303 MWe geothermal power plant in Hellisheiði, Iceland, was commissioned in 5 stages during the years 2006-2011. The first stage was completed in 2006 with two high pressure geothermal turbines of 45 MWe capacity each. The second stage was completed in 2007 with one low pressure geothermal turbine of 33 MWe capacity. The third stage was completed in 2008 with two additional high pressure geothermal turbines, 45 MWe each.
In 2010 a heating plant for hot water generation was added to the plant, intended for district heating. The heat output of the first stage is 133 MWth and two further 133 MWth stages are to follow later. At the same time the Hellisheiði hot water main was put into service. The main is a 19,5 km long pipeline, 0,9-1,0 m in diameter, that carries hot water to Reykjavík. In 2011 the 5th stage of the plant was finished, which includes two new 45 MWe high pressure geothermal turbines, similar to the former turbines, situated in a new power house in Sleggjubeinsdalur.
The plant utilizes 500 kg/s of 180°C geothermal steam for electrical generation. The hot fluid is extracted from 30 wells, 2.000 – 3.000 m deep, and is led through steam and mist separators before entering the turbines. The high pressure steam gathering system operates at 9 bara pressure. The low pressure steam is generated with flashing of brine water from the steam separators at a pressure of 2 bara. The generating units are of single flow, single flash type with axial exhaust. Cooling is achieved through wet cooling towers of the counter flow type.
The main components of the electrical system for each unit consist of a 50 MVA generator, 50 MVA step-up transformer to 220 kV transmission voltage, an 11/11 kV transformer for connection to the 11 kV station service system and two 11/0,4 kV transformers for station service. The generating units, as well as the 11 kV and 0,4 kV distribution boards, are monitored and controlled by the state of the art control- and protection equipment.
The Result
Reykjavík Energy owns the Hellisheidi geothermal power plant, a combined heat and power plant located about 20 km from Reykjavík in south-west Iceland. The area is one of Iceland’s most active high enthalpy areas. A new area, at Gráuhnúkar, is being investigated for steam and fluid extraction. The purpose of the plants is to meet increased demand for electricity for industrial and domestic use and for hot water for heating. The 303 MWe geothermal power plant in Hellisheiði, Iceland, was commissioned in 5 stages during the years 2006-2011. The first stage was completed in 2006 with two high pressure geothermal turbines of 45 MWe capacity each. The second stage was completed in 2007 with one low pressure geothermal turbine of 33 MWe capacity. The third stage was completed in 2008 with two additional high pressure geothermal turbines, 45 MWe each.
In 2010 a heating plant for hot water generation was added to the plant, intended for district heating. The heat output of the first stage is 133 MWth and two further 133 MWth stages are to follow later. At the same time the Hellisheiði hot water main was put into service. The main is a 19,5 km long pipeline, 0,9-1,0 m in diameter, that carries hot water to Reykjavík. In 2011 the 5th stage of the plant was finished, which includes two new 45 MWe high pressure geothermal turbines, similar to the former turbines, situated in a new power house in Sleggjubeinsdalur.
The plant utilizes 500 kg/s of 180°C geothermal steam for electrical generation. The hot fluid is extracted from 30 wells, 2.000 – 3.000 m deep, and is led through steam and mist separators before entering the turbines. The high pressure steam gathering system operates at 9 bara pressure. The low pressure steam is generated with flashing of brine water from the steam separators at a pressure of 2 bara. The generating units are of single flow, single flash type with axial exhaust. Cooling is achieved through wet cooling towers of the counter flow type.
The main components of the electrical system for each unit consist of a 50 MVA generator, 50 MVA step-up transformer to 220 kV transmission voltage, an 11/11 kV transformer for connection to the 11 kV station service system and two 11/0,4 kV transformers for station service. The generating units, as well as the 11 kV and 0,4 kV distribution boards, are monitored and controlled by the state of the art control- and protection equipment.
Icelandic
