JPS59155578A - Ocean temperature difference electric power generating system - Google Patents

Abstract

PURPOSE:To increase the amount of retrieving electric power remarkably in accordance with the seasonal fluctuation of seawater temperature by a method wherein a signal to control a water introducing amount is outputted from a control indicator, indicating the opening degree of an adjusting valve based on the temperature difference. CONSTITUTION:When the seawater temperature exceeds a design temperature, the opening degree of the adjusting valve 4 is controlled by a signal from the control indicator 11 to increase steam pressure. At the same time, the movable blades of a hot-water pump 1 and a cool water pump 8 are controlled by the water introducing amount control signal from the control indicator 11 to keep the generating output of a turbine 5 near a rating output. On the other hand, when the seawater temperature is lower than the design temperature, the adjusting valve 4 is controlled and, at the same time, the movable blades of the hot- water pump 1 and the cool water pump 8 are controlled by the water introducing amount control signal from the control indicator 11 to increase the seawater introducing amount.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an ocean temperature difference power generation system, and particularly to a power generation system used when the surface temperature of the ocean changes seasonally.

[Technical background of the invention]

FIG. 1 shows a schematic configuration diagram of a conventional ocean temperature difference power generation system. A hot water pump 1 takes hot water from the ocean surface layer and sends it to an evaporator 2. The working fluid flowing through the evaporator 2 is converted into steam by obtaining energy from hot water, and is supplied to the turbine 5 via the steam stop valve 3 and the control valve 4. A generator 6 is operated by the turbine 5 to generate electricity. The steam that has lost its energy by operating the turbine 5 is introduced into the condenser 7, where it is cooled by cold water drawn from deep in the ocean by the cold water pump 8 and becomes a liquid.

The working fluid thus returned to liquid form is configured to be sent to the evaporator 2 again by the working fluid pump 9. Note that the vapor pressure of the working fluid flowing out from the evaporator 2 is regulated by the regulating valve 4, and the signal instructing the opening degree of the regulating valve 40 is given based on the temperature difference between hot water and cold water. ing. That is, a temperature sensor 10 is installed in the ocean surface layer, and the control indicator 11 inputs the hot water temperature of this temperature sensor 10, calculates the temperature difference with the deep ocean layer, and sets the valve opening degree to the control valve 4. Outputs a signal that instructs. In this case, the temperature detector 1° is installed only in the ocean surface layer, because the temperature in the ocean surface layer changes seasonally throughout the year, but the temperature in the deep ocean layer is almost constant throughout the year.

In addition, in the conventional ocean temperature difference power generation system, the hot water pump 1
Since the seawater intake amount of the cold water pump 8 was always constant, the steam pressure was increased when the hot water temperature rose above or below a certain planned temperature, and conversely, when the temperature fell below the planned temperature, the steam pressure was lowered and the evaporator 2 The opening degree of adjustment 9P4 was adjusted so as to maintain the heat input at 9' near the rated value.

[Problems with background technology]

In such a conventional ocean temperature difference power generation system, the period during which the sending end output of the generator 6 is positive with respect to the expected change curve of seawater temperature is only a little over 5 months, and the annual total output based on the rated output is The ratio of the amount of electricity at the transmission end, that is, the utilization rate of the plant, was only about 35%, which had the disadvantage of impairing economic efficiency.

[Purpose of the invention]

The purpose of this invention is to dramatically increase the amount of recovered electricity and increase the utilization rate of the plant in response to seasonal fluctuations in hot water temperature, thereby improving the economic efficiency of the plant. The system is to provide.

[Summary of the invention]

In order to achieve the above object, the present invention includes a hot water pump that takes hot water from the ocean surface layer, a cold water pump that takes cold water from the deep ocean layer, and a high-energy working fluid that gains energy from the hot water and loses energy from the cold water. a control valve that adjusts the pressure on the side; and a control indicator that detects a temperature difference between the hot water and the cold water and outputs a signal instructing the opening degree of the control valve based on this temperature difference. In the ocean temperature difference power generation system, the control indicator further outputs a signal to control the amount of water intake according to the temperature difference, and in response to this water intake amount control signal, the hot water pump and the cold water pump It is characterized by operating to increase or decrease the amount of water intake.

[Embodiments of the invention]

The present invention will be described in detail below based on examples.

FIG. 2 is a schematic diagram showing an embodiment of the present invention. Note that the same parts as shown in FIG. 1 are given the same reference numerals and their explanations will be omitted. The difference from the conventional system shown in FIG. 1 is that in addition to outputting a signal instructing the opening of the control valve 4, the control indicator 11 also controls the amount of water taken into the hot water pump 1 and the cold water pump 8. It has the function of outputting a signal.

[Control indicator] In order to automatically increase or decrease the amount of water intake in response to signals from the hot water pump 1 and the cold water bonder 2,
A variable vane type seawater pump may be used.

Next, the operation of the system shown in FIG. 2 will be explained.

When the hot water temperature exceeds the planned temperature, the opening degree of the regulating valve 4 is controlled by a signal from the control indicator 11 and the steam pressure is increased, as in the conventional case. However, with this kind of control, the heat drop that can be used by the turbine 5 becomes too large and the generated power becomes excessive.
It is necessary to reduce the flow of hot and cold water to about 5%.

The movable blades of the hot water pump 1 and the cold water pump 8 are controlled by a water intake amount control signal from the control indicator 11. Since the movable blade type seawater pump requires less power when the flow rate is reduced, the output generated by the turbine 50 can be maintained near the rated value while reducing the in-house power.9. As a result, the output at the sending end is increased. On the other hand, when the hot water temperature is just below the planned temperature, the regulating valve 4 is controlled and the steam pressure is lowered in accordance with the decreasing tendency of the hot water temperature, which is the same as in the prior art. However, if this is done alone, the heat drop that can be used by the turbine 5 becomes too small, resulting in an extremely low power generation. In order to prevent this output reduction, it is necessary to increase the flow rate of the working fluid, and for this purpose, it is necessary to increase the amount of water taken by the hot water pump 1 and the cold water pump 8.

The water intake amount control signal from the control indicator 11 controls the rotor blades of the hot water pump 1 and the cold water pump 80, thereby increasing the amount of seawater intake. For movable vane type seawater pumps, the required power tends to increase as the flow rate increases, but since there are many periods in which the generating end output increases more than the increment of the in-house power, the generating end output eventually becomes less than the in-house operating power. The operable period during which the sending end output is positive is longer than that of conventional power generation systems. In addition, the plant utilization rate will increase to about 30%.

FIG. 3 is a diagram comparing the output around 1 between the conventional power generation system and the power generation system according to the present invention. Figure 3 shows monthly changes in seawater temperature.As is clear from this figure, surface layer warm water temperature fluctuates seasonally, and when the surface layer standard temperature is set at 5℃, The period in which the temperature is exceeded is only three months. On the other hand, it can be seen that the deep cold water temperature is almost constant throughout the year.

Figure 3 (the group shows the change in the power generation end output), where the dashed-dotted line shows the case using the conventional power generation system, and the solid line shows the case using the power generation system according to the present invention.From the figure As is clear, in the case of the present invention, fluctuations in the output output due to seasonal fluctuations are extremely small.

Figure 3 fc) is a diagram showing seasonal fluctuations in the total labor force at the station. If the surface layer standard temperature is set to 25C and the standard power is 1600 KW, the surface layer hot water temperature is 25C.
If C or less, the total in-house labor is the standard power of 1600 KW.
Figure 3 (1)) is a diagram showing seasonal fluctuations in the direct output. A conventional power generation system is shown by a dashed line, and a power generation system according to the present invention is shown by a solid line. In the conventional system, the period during which the direct output end is positive, that is, the operable period was only 5 months at most, but by adopting the system of this invention, the period can be increased to 9 months. Recognize.

Table 1 summarizes the above results.

Table 1 Table 1 shows the results of a trial calculation corresponding to the seasonal fluctuations in output trends shown in Figure 3.

In the embodiment described above, a movable blade type seawater pump was used as the hot water pump 1 and the cold water pump 8, but instead of a fixed type seawater pump, a variable speed type seawater pump using a motor I Hayabusa variable speed control etc. It may be a pump 3. In addition to controlling the hot water pump and 4-water pump 111, the fluid pump 9 that circulates the working fluid is of variable speed type.
It is also possible to control the rotation speed in accordance with the temperature of the product water.

〔Effect of the invention〕

As described in detail based on the embodiments, in this invention, in addition to controlling the vapor pressure of the working fluid according to the temperature difference between singing water and cold water, the intake amount of hot water and cold water is also controlled. Compared to conventional power generation systems, this system has the advantage of increasing the annual sound transmission end's stress slippage and improving the plant utilization rate. Therefore, it is an excellent method that can improve the unit price of electricity by 1 from the economical point of view.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a schematic configuration of a conventional system, and FIG. 2 is a diagram showing a schematic configuration of a power generation system according to an embodiment of the present invention.
FIG. 3 is a diagram comparing the conventional power generation system and the power generation system according to the present invention and showing their expected output by month. 1... Hot water pump, 2... Evaporator, 3... Steam 1
F, valve, 4... control valve, 5... turbine, 6...
・Generator, 7... Condenser, 8... Cold water pump, 9.
... Working fluid pump, 10... Temperature sensor, 11...
・Control indicator. Applicant's agent Kiyoshi Inomata

Claims (1)

[Claims] (1) A hot water pump that takes hot water from the ocean surface layer, a cold water pump that takes cold water from the deep ocean layer, and adjustment of the pressure on the high-energy side of the working fluid that gains energy from the hot water and loses energy from the cold water. In an ocean temperature difference power generation system comprising a valve and a control indicator that detects a temperature difference between the hot water and the cold water and outputs a signal instructing the opening degree of the adjustment valve based on this temperature difference, the control The indicator further outputs a signal for controlling the amount of water intake according to the temperature difference, and the hot water pump and the cold water pump operate to increase or decrease the amount of water taken in response to this water intake amount control signal. An ocean temperature difference power generation system.