The Penzhin Tidal Power Plant Project is a set of proposals for construction of tidal power plant in the Penzhin Bay, which is an upper right arm of Shelikhov Bay in the north-east corner of the Sea of Okhotsk. Because Penzhin Bay has one of the strongest tides, several projects of power station was suggested. One of proposed variants presumes installed capacity 87 GW and annual production 200 TWh of electricity.

Geographically, the dam of the power station would extend through the administrative border of Magadan Oblast and Kamchatka Krai of Russia.

The altitude of tides in Penzhin Bay constitutes 9 metres (30 ft) and reaches 12.9 metres (42 ft) in the case of syzygian tides, that is the highest magnitude for Pacific ocean. As the area of the bay basin is 20,530 km² (7,930 mi²), it corresponds to diurnal discharge of 360−530 km³ (86−130 cu mi). This water rate is 20-30 times higher, than it is for the Amazon River, the biggest river of the Earth. Two projects were developed for tidal power stations. First of them is earliest in time and proposes use of entire basin of the bay. The second one suggests smaller scale plant, which must use northern part of basin with higher tides:

Variant Tide altitude,
m \ ft
production, TW·h
of research
South site 11 \ 36 87,1 190-205 1972—1996
North site 13.4 \ 44 21,4 50 1983—1996

Due to the lack of local consumers and power lines, there are suggestions of a discrete work of the station to supply power-consuming productions. One of such regulators, for example, would be the production of liquid hydrogen.

Hydrological potential of the bay

The tides in the Penzhin Bay of the Sea of Okhotsk is highest one for Pacific ocean reaching the height 13.4 metres (44 ft). The tides in Shelikhov Bay is a duirnal type, the area of Penzhin Bay basin is 20 530 km². Hence, the assumption, that the average magnitude of tide is equal to 10 metres (33 ft), gives the diurnal flow of water in the bay equal to 410.6 cubic kilometres (98.5 cu mi) or average discharge 4.75×106 m3•sec-1.

The passing stream has its own potential energy, which in the gravity field of Earth is above zero only in the case of non-zero head of water (HHead) and can be expressed as follows:

 E = [\rho_{sw} \cdot S_{Basin} \cdot (H_{Tide} - H_{Head})] \cdot g \cdot H_{Head}, (1)

where E denotes potential anergy; ρsw — density of sea water, equal to 1,027 kg/m³; SBasin — area of basin; HTide — height of the tide and g — gravitational acceleration, set to 9.81 m/sec². The part of expression in brackets denotes terms defining the mass of water passing through the basin daily.

As it can be seen in formula (1), the potential energy becomes zero in the case of zero head of water and in the case of equal heights of head and tide. Regarding this formula as function of head (HHead), it is a parabolic function, which has the maximum at HTide = 2•HHead or at HHead = 5 m. This value of HHead gives two times lower height of tide in the bay and twice smaller average discharge of water — 5 m and 2.38×106 m3•sec-1 (205.3 km³/day), correspondingly.

The substitution of obtained parameters into (1) and dividing it by the day length in seconds gives the average capacity 120 GW. The latter one allows to obtain 1,054 TW•h or 3.79×1018 Joules of energy annually. Depending on the efficiency of conversion of potential energy into electricity, the total quantity of electricity and electric capacity will have somewhat lower values. The assumption, that the efficiency of conversion is equal to 96%, gives an average electric capacity 115 GW and available amount of electricity 1,012 TW•h or 3.64×1018 J per year.