Voronezh Nuclear Heating Plant (NHP)
The Voronezhskaya AST is a nuclear power plant comprising two power units of 500 MW each. It is intended for year-round work in the basic mode in the centralized heat supply system of the city of Voronezh in order to cover the existing heat deficit in the city (VAST was supposed to provide 23% of the annual heat and hot water needs of the city). The VAST site is located on the right bank of the Voronezh River, in the Shilovo microdistrict. Distance from urban development is 6.5 km. The construction of the station was carried out from 1983 to 1990. Currently discontinued. By the decision of the Voronezh City Council of People's Deputies dated June 5, 1990, the construction of the facility was stopped taking into account the results of the city referendum on the heat supply of the city of Voronezh.
Low temperatures during the greater part of the year is characteristic for a majority of regions in Russia. Heating period for town dwellings lasts usually from 7 to 10 months a year. Contemporary dwellings are also provided with centrally-supplied hot potable water for sanitary and hygienic purposes. Moreover, hot water is supplied to public buildings for air conditioning. Average per capita heat consumption in households amounts to about 24 GJ a year and has been increasing over the years.
Fast growth of towns and gradual improvements in the quality of dwellings in the Sixties and Seventies resulted in a dominant share for fossil fuel in the production of heat. By the end of the Eighties it attained 42%, i.e. 1.72 times higher than that for electricity production. The town-building concept adopted in the country has been based traditionally upon the utilization of centralized heating, i.e. large systems for transport and distribution of heat from cogeneration plants and boiler stations to blocks of buildings and to separate multiflat houses. When NPPs supply heat to large CHSs conventional co-generation power plant plays the role of a load-following source of heat, as well as the town's peak load boilers which come on-line at the lowest ambient temperatures. A co-generation power plant also serves as a back-up source of heat in case the NPP is under a shut-down.
For heating of large towns with significant heat demands and expensive fossil fuel, a heat only low-temperature reactor AST-500 was developed in the late 1970s. From the very beginning, the reactor had been developed as a heat source of enhanced safety to exclude practically any risk to the population from a nuclear heating station (NHS) situated near the center of heat loads. Minimal alienated area and small needs in raw water facilitate NHS siting in the vicinity of towns and in densely populated regions. This simplifies heat transport, while reduced parameters of a reactor coolant and elimination of energy-conversion system give possibility to simplify the structure of a heating reactor and to reduce capital cost of NHS and costs to the CHS.
In the late 1970s, all the necessary conditions for nuclear heating plants (NHPs) were met in two Sites in Russia: (Gorky and Voronezh), where construction of the two pilot nuclear district heating plants (AST-500) started in early 1980s. The reactor unit includes the water cooled and moderated integral type reactor. The reactor core consists of 121 fuel assemblies. Fuel elements are made of the Zr-base alloy tube with dimensions of 13.6x0.9 mm which are filled with fuel pellets of sintered UO2. For the first reactor fueling the fuel with the enrichment of 1.0, 1.6, 2.0% is used. The fuel burnup under steady-state conditions constitutes 14 MWxday/kg. The pressure in the primary coolant circuit is 2.0 MPa, the temperature at the core inlet is 131 deg C, the temperature at the core outlet is 208 deg C. The temperature of the water supplied for distript heating is 150 deg C It is concluded that the structure of the reactor safety and external impact protection systems provides the safety level, permitting the AST-500 NPP siting near cities.
In the USSR all NPPs were invested from the State budget and plenty of machine-building plants were involved by the governmental decrees in the production of equipment necessary for the nuclear power generating and heating only plants. Unfortunately, the established nuclear equipment production cooperation collapsed with the USSR. In 1990 decisions were adopted by regional administrations to cease the NHP construction in Gorky and Voronezh. Until that time two sets of AST-500 RP components were delivered to the Gorky Site and one set to Voronezh. By that time construction and erection works of the first unit of the Gorky NHP was 83% complete (in cost term) and more than 30% on the Voronezh Site.
The referendum in Voronezh in May 1990 stopped the construction of a nuclear heating plant in the city. The referendum in microcosm showed that the late Gorbachev period was, in many ways, the high point of democracy in Russia. The authorities not only acquiesced in allowing the referendum to go ahead, they also tended, whenever an issue arose, to rule in favour of the most liberal interpretation of the law. It was only after the fall of Gorbachev that the democratic will of the people came under challenge. First, the authorities dismissed the result of the referendum on legal grounds; and second, they argued that the public as a whole was not interested or knowledgeable enough to make such an important and complex decision.
In 1995 a level of centralized district heating loads was about 1,200 x 10exp6 Gcal (in 1990 it was 1,550 x 10exp6 Gcal) in the European regions of Russia. This declining trend in the district heating loads is explained by macro-economical difficulties and the significant reduction in the industrial heating loads. However, the district heating loads in the region are now starting to buildup and are expected to rise further in future. The European regions are remote from the fossil fuel production areas and the cost of fossil fuel tends to rise so that it is expected to reach the level of West-European market cost. Furthermore, impact of conventional power industries on the environment is most hazardous in large cities. On the other hand, there are many suitable places for the NHP siting in these regions.
In 1994, under pressure of the acute district heating problem in the city, the regional administration initiated the NHP environmental impact review by the team of a public commission composed of qualified local scientists and engineers. After a comprehensive study and consideration of the design materials, and visiting the NHP Site, a conclusion was drawn up that confirmed the assured safety of the plant for both the local inhabitants and the environment. As a result the construction work on the plant Site was resumed in 1996.
As of November 2011, the project AST-500 is officially closed. The question of reprofiling the site in the interests of the Voronezh region and the concern Rosenergoatom is being considered. As of August 1, 2012, 70% of the objects of the Voronezh AST were sold. In July 2019, information appeared on the plans for dismantling buildings of VAST, and demolition work was scheduled to begin in October 2019.
|Join the GlobalSecurity.org mailing list|