THE PIACENZA THERMAL POWER PLANT Centrale di Piacenza Via Nino Bixio, 27 – 29100 Piacenza Phone 0523/668111 - Fax 0523/668400 E-mail: centrale.piacenza@edipower.it Emissions: http://www.arpa.emr.it/pubblicazioni/piacenza/generale_1329.asp

YESTERDAY

Aside the present Piacenza  power plant, today we can still find the old "Emilia", the former power plant designed by architect Piero Portaluppi in years 1925-26 and considered a wonderful monument to man work. The works for its construction were carried out by many skilled Italian companies employing more than 1,000 workers.

Two turbogenerators units "Westinghouse" of 70 MW each were operated in the equipment room, and the total efficiency of the plant was above 35%, in line with the best technologies available at that time in thermal power plants installed in Europe.

The tecnology adopted in the power plant was the "single unit" one, that is (based on the steam supply of each turbogenerator by one single boiler) without connections between the two units.

The steam production capability of each boiler of Emilia Power Plant was more than 210 t/h at 103 atm pressure.

Between 1965 and 1967,  two conventional 330 MW units were erected in a building (named the “Levante Power Plant”), in front of the old Emilia Power Plant.

TODAY

TECHNICAL OUTLOOK
As provided for in D.M. 9/2001, Edipower implemented  the revamping of the Levante Power Plant into a modern gas turbine combined cycle, consisting of two gas turbines and one steam turbine having total capacity of approximately 800 MW.

With the post-combustion system installed in the recovery boilers, it is possible to increase the steam production and obtain an increase of 50 MW on the power output of the steam turbine.

The preliminary works for the site began on 30 December 2002 and the combine cycle commissioning occurred in December 2005.

The new plant is equipped with:

• 2 gas turbines
• 2 heat Recovery Steam Generators , equipped with 90 m height stacks for gas exhaust
• 1 steam turbine using the steam produced by the two heat recovery steam generators
• 1 steam condenser
• 3 generators
• 3 main transformers

The condenser cooling water is taken from the Po River and returned to the same using the existing intake and discharge works.

The total efficiency of the plant is equal to 56%.

THE AGREEMENT WITH THE MUNICIPALITY
Based on the agreement signed with Piacenza Municipality in February 2005, the Piacenza power plant – from 2006 to 2010 – shall supply heat for the town district heating system, up to  20 MWt and, after 2010, up to 160 MWt.

With the dismantling of civil boilers, the district heating system shall allow a highly significant pollutant reduction in the air.

The agreement signed between Edipower and the Municipality of Piacenza includes also a contribution for the Emilia Power Plant Integrated Project.

The Integrated Project envisages the partial recovery of Emilia Power Plant to house the Leap Consortium – a laboratory for the efficiency and environmental compatibility of power technologies – and a area for a museum dedicated to the town.

TECHNICAL DESCRIPTION

GAS TURBINES
The two gas turbines (GT) installed in the combined cycle have a power output of approx. 270 MWe each.

Each one includes the axial air compressor that supplies the necessary  air for the combustion and cooling of the hot parts of the equipment.

The burners are of the low NOx type to limit emissions within the limits requested by the regulations in force.

The thermal power supplied by combustion is transformed into mechanical power in the gas turbine and then into electric power through the coupled generator.

Flue gas coming out from the gas turbines is sent to the heat recovery steam generators, where it exchanges heat for steam production and, then,  is discharged at the stack.

HEAR RECOVERY STEAM GENERATORS
Heat Recovery Steam Generators (HRSG) are surface heat exchangers that, using the thermal power of flue gas of the GTs, produce the steam necessary to operate the Steam Turbine.

STEAM TURBINES
The main technical data are:

• Type: 4 cylinder impulse-reaction
• Capacityr: 340 MW
• Steam Pressure: SH 171 Ata
• Steam Pressure: RH 45 Ata
• Steam Temperature: SH 538°C
• Steam Temperature: RH 538°C
• Pressure at discharge: 0.050 Ata

GENERATORS
The two generators coupled to the gas turbines are of the three-phase type, cooled in closed cycle hydrogen atmosphere.

The third generator (the one coupled to the steam turbine) is of the three-phase type with mixed cooling (closed cycle hydrogen atmosphere and closed cycle deionised water cooling for stator windings).

MAIN TRANSFORMERS
Each generator is connected to its main transformer that  increases voltage up to 380 KV to enable electric power to be inlet in the transmission grid.

CONDENSERS
The condenser is of the surface type, with one-way horizontal pipes, crossed by the water of the Po River. The steam discharged by low pressure stages of the turbine, passing in the pipes, condenses and transforms into water, which is collected in the hot well and, taken by extraction pumps, is newly sent to the HRSGs, after physical-chemical filtration treatment.

FUELS
The combined cycle is natural gas fired only. Gas is supplied  through a gas pipeline connected to the national gas grid.

ENVIRONMENTAL PROTECTION

The Piacenza Power Plant is equipped with:

• "low NOx" combustion systems to reduce the emissions of nitrogen oxides (NOx).

The emissions to the atmosphere of nitrogen oxides (NOx), sulphur dioxide (SO₂), particulate and carbon monoxide (CO) are monitored and continuously recorded through an Emission Monitoring System (SME); measured values are transmitted every week to the relevant control authority (ARPA).

The Air Quality Monitoring Network (RRQA) for the measurement of some pollutants in the ground is owned and managed by the Province; the Piacenza Power Plant contributed to the costs for the implementation and management of the network itself.

The waste waters (acid/alkaline, oily, biological) are treated in a purposely designed plant (ITAR, Waste Water Treatment Plant) and continuously tested before the discharge.

All activities that interact or may interact with the environment are managed in accordance with the ruling environmental laws and the available state–of-the-art techniques.

The Environmental Management System implemented in the power plant was certified in May 2003 according to the UNI EN ISO Std. 14001.

To foster the ongoing improvement of the environmental performances and the information to the public, the management of the Piacenza Power Plant has voluntarily adopted the EU Ecomanagement and Audit Scheme (EMAS) and obtained the registration in November 12, 2003 with the number  I-000167.