Hot Water System Pump Speed Control for Energy-Efficient Tank Charging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing hot water treatment systems are inefficient and uncomfortable due to unnecessary high pump speeds, leading to increased energy consumption and prolonged storage tank charging times.

Innovation Solution

A method that controls the speed of pumps in a hot water treatment system based on actual temperature values and setpoints, using a control strategy to adjust pump speeds and heat generator operation, ensuring only necessary energy is used for heating, and optimizing the stratification of the hot water storage tank.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If pump speeds are increased to heat water faster, then productivity is improved, but energy consumption increases

Engineering Contradiction:
Improvewater heating speedVSAvoidpump energy consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The pump speed is made dynamically adjustable based on real-time temperature measurements. The control unit continuously monitors the actual temperature at the heat exchanger outlet and adjusts the pump speed accordingly, transitioning from static high-speed operation to dynamic adaptive speed control that matches actual heating requirements.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

A feedback control mechanism is implemented where the actual temperature value measured at the heat exchanger outlet is fed back to the control unit. This feedback signal is used to regulate pump speed, creating a closed-loop control system that automatically adjusts pump operation based on temperature deviations from the setpoint.

Inventive Principle:
Principle #23Feedback

2Productivity

If pump speeds are increased to load the storage tank faster, then productivity is improved, but loss of energy increases

Engineering Contradiction:
Improvestorage tank charging speedVSAvoidunnecessary energy consumption
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The system uses its own temperature measurement capability to automatically regulate its operation. The control unit monitors the actual temperature and self-adjusts the pump speed to maintain optimal charging conditions, eliminating the need for external control interventions and preventing unnecessary high-speed operation.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The pump speed parameter is changed dynamically based on temperature conditions. Instead of maintaining constant high speed, the system adjusts the speed parameter according to the actual temperature value, reducing energy loss when the temperature setpoint is already achieved or exceeded.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If the heat generator operates at high output to heat water faster, then productivity is improved, but loss of time increases due to prolonged operation

Engineering Contradiction:
Improvewater heating rateVSAvoidheat generator operation duration
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The heat generator output is dynamically adjusted based on real-time temperature feedback. The control unit modulates the heat generator operation to match actual heating needs, transitioning from static high-output operation to dynamic adaptive control that reduces unnecessary prolonged operation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

Temperature feedback from the heat exchanger outlet is used to regulate heat generator operation. When the actual temperature approaches or reaches the setpoint, the feedback signal automatically reduces heat generator output, preventing prolonged operation and reducing time loss.

Inventive Principle:
Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach reduces energy consumption, maintains comfort by ensuring the hot water tank is loaded efficiently, and extends the use of residual heat, while minimizing unnecessary pump speeds and heat generator operation.

Implementation Method 1

heat generator (14), with which the heat transfer medium is heated

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

heat exchanger (28), with which the heat transfer medium is heated

Methodology Applied
Scientific EffectHeat exchanger: Heat Exchanger

Data Source

PatentEP3139103B1Method for providing warm drinking water
Publication Date: 2019.05.01 ROBERT BOSCH GMBH
  • EP3139103B1 patent drawingFigure 1~2
  • EP3139103B1 patent drawingFigure 3
  • EP3139103B1 patent drawingFigure 4~5

AI summary

The invention relates to a method for providing hot water, in particular hot drinking water, with a hot water treatment system which has at least one heat generator and at least one first pump for circulating a fluid, in particular water, in at least one primary circuit and at least one hot water tank and at least one second Pump for circulating a fluid, in particular water, in particular drinking water, in at least one secondary circuit, wherein at least one heat exchanger is arranged between the heat generator and the hot water tank. With the first pump, the fluid is pumped through a primary side of the heat exchanger (28). With the second pump, the fluid is pumped through the hot water tank and through a secondary side of the heat exchanger. The speed of the at least one pump is also regulated. It is proposed that an actual value of the temperature at the secondary-side outlet of the heat exchanger is determined and that a hot water storage tank setpoint value is specified for a temperature of the hot water storage tank or is calculated taking into account a control strategy. It is also proposed that the speed of the at least one controllable pump is controlled using the control strategy in such a way that the actual value is higher than or equal to the hot water storage tank setpoint, with the at least one pump being operated at a reduced speed if necessary. The invention further relates to a system for providing hot drinking water, in which the above method runs, and a heat generator for this.