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The OPEN100 Nuclear Power Plant is based on the standard nuclear pressurized water reactor (PWR) which uses water as both the moderator and the coolant for the reactor core. The nominal rating of 100 MWe is approximately 1/10 the size of a modern PWR plant. The smaller size has the feature of allowing for a proven and established design concept while increasing access to equipment through an expanded vendor supply chain. 

Nominal Rating: 100 MWe

Reactor Type: Pressurized Water Reactor

Fuel Type: Enriched Uranium Dioxide

Power Cycle: Rankine Steam Cycle

Pressurized Water Reactor.jpg

Pressurized Water Reactor

Like larger PWRs in operation today, the OPEN100 operates with a primary loop to generate hot water and a secondary loop to create and transfer steam through a turbine. Thermal energy is transformed to mechanical and then electrical power through a turbine generator set before returning the condensate back to the steam generator as part of a continuous cycle. Unlike large nuclear plants, but otherwise common throughout industry, the OPEN100 will employ an ACC which eliminates the need for high water requirements, that limit siting to large bodies of water.

Primary Loop Pressure: 2100 - 2250 psia

Primary Loop Temperature: 570-620F

Secondary Loop Pressure: 400 psia

Secondary Loop Temperature: 600F

Pressurized Water Reactor
Nuclear Island

Nuclear Island

The main components of any Nuclear Steam Supply System (NSSS) consist of the Reactor and the Reactor Coolant System (RCS). The RCS on the OPEN100, like any PWR, is comprised of several pumps to circulate the coolant, a pressurizer to maintain the constant pressure on the system, a steam generator, and the piping to transport the water back and forth between the reactor and the steam generator.

Heat Generated: 350 MWt

Primary Loop Flow: Pressurized Water Reactor

Primary Loop Pressure: 2250 psia

Hot Leg Temperature: 620F

Cold Leg Temperature: 450F

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Balance of Plant
Balance of Plant.jpg

Balance of Plant

The balance of plant (BOP) for the OPEN100 design consists of a steam generator, piping to transport the steam to the turbine, an air-cooled condenser (ACC) to return the exhaust back into condensate, and pumps and auxiliary components to condition the water prior to returning it to the steam generator. This is simpler than the equivalent system in the modern PWR plant due to the reduction of several stages of steam extraction and reheating.

Turbine Net Generated Power: 100 MWe

Steam Flow: 1,425,000 pph

Steam Type: Superheated

Main Steam Pressure: 400 psia

Main Steam Temperature: 600F

Overall Site

Overall Site

The OPEN100 design includes three main structures. The containment bldg. includes the primary NSSS equipment; and then two additional buildings which support its operation and include the control room, BOP equipment, and auxiliary equipment for operations. External to these three structures are the Air Cooled Condensers, located outdoors, connected to the turbine building via large ductwork. This results in a simple and aesthetically pleasing layout which can be replicated in an identical configuration irrespective of site conditions.

Site Acreage: 8.25

Total Building Square Footage: 106,000

Containment Building Square Footage: 10,000

Turbine Building Square Footage: 48,000

Auxiliary Building Square Footage: 48,000

Overall Site.jpg
Environment Impact Assessmet
Environment Impact Assessment.jpg

Environmental Considerations

Important to infrastructure development of any kind is minimizing its effects on the natural environment. While varying local site conditions often lead to expensive site specific engineering, the OPEN100 base design includes standard site agnostic features to reduce land disturbance and factors in full lifecycle considerations as well. Specifically the OPEN100 plant minimizes demands for water, land area, and external infrastructure additions.

Land Location: Semi-rural, near load center

Soil Type: Type B

Construction Area: 10 acre

Construction Erosion Boundary: Sediment barrier

Water Consumption: <60 gpm

Waste Heat Removal: Air

Environmental Contaminants: None

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