Bus Roof Solar Air Conditioning Integration

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Solution Overview

Problem

Existing bus air conditioning systems on the roof lack an integrated solution for efficient cooling and ventilation, especially when stationary, relying on insufficient solar energy for prolonged operation and lacking a functional connection between solar power generation and air conditioning components.

Innovation Solution

The air conditioning system's outer cladding is designed with integrated solar cells generating power, which operates an electrically driven ventilation and venting device, providing a self-supporting, compact system for cooling and dehumidification, reducing fuel consumption and enhancing interior comfort.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If solar cells are attached to a vehicle for air conditioning operation, then solar energy is obtained for compressor operation, but the energy obtained is regularly not sufficient for longer operation

Engineering Contradiction:
Improvesolar energy for compressor operationVSAvoidoperation duration
Core Design Contradiction:
Use of energy by moving objectVSDuration of action of moving object

Solution Approach 1:

The patent combines the air conditioning system with the sunroof structure, integrating solar cells, compressor, and ventilation device into a single unified module. This merging allows the solar-powered ventilation to work in conjunction with the air conditioning system, enabling longer effective operation duration by utilizing solar energy for pre-cooling and ventilation functions that support the main AC operation.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sunroof module is designed to perform multiple functions: it serves as both a sunroof structure and a solar-powered air conditioning unit. The ventilation device can operate independently to provide airflow and cooling when solar energy is available, while also supporting the main AC system during periods of sufficient solar generation, thereby extending the effective operation duration beyond what a standalone AC compressor could achieve.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If solar cells are integrated into the sunroof for power generation, then electricity is generated for fan operation, but the system lacks functional connection with the air conditioning system

Engineering Contradiction:
Improvepower generation capabilityVSAvoidsystem integration
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges the solar cell array, ventilation device, and air conditioning system into a single integrated module housed within the sunroof structure. This combination creates direct functional connections between components, allowing solar-generated electricity to power the ventilation device which works in tandem with the AC system's compressor and refrigerant cycle, eliminating the functional disconnection present in separate systems.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The integrated module serves multiple functions within a single structural unit: the solar cells generate electricity, the ventilation device provides airflow, and the AC system delivers cooling. This multi-functional design ensures that the power generation capability is directly coupled with the air conditioning function, creating a cohesive system where components work together rather than operating independently.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Temperature

If air conditioning system is installed on bus roof, then cooling function is provided, but the system lacks integrated ventilation device for stationary operation

Engineering Contradiction:
Improveinterior coolingVSAvoidsystem integration
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent combines the traditional AC cooling system with a solar-powered ventilation device in a single integrated module. The ventilation device is positioned to work with the AC system's air handling components, creating a unified system that provides both active cooling (when AC is running) and passive solar ventilation (when stationary), thereby adding ventilation functionality without requiring a completely separate system installation.

Inventive Principle:
Principle #5Merging (Combining)

4Adaptability or versatility

If separate solar system and air conditioning system are installed, then both functions are provided, but installation effort and costs increase

Engineering Contradiction:
Improvefunctional capabilityVSAvoidinstallation effort
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent integrates the solar cell array, ventilation device, and air conditioning system into a single pre-assembled module that replaces or supplements the traditional sunroof structure. This unified module reduces installation effort by eliminating the need to separately mount solar panels, ventilation equipment, and AC systems, while still providing all necessary functions through their integrated design.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The module serves multiple functions within a single installation: it provides solar power generation, active air conditioning cooling, and passive solar ventilation. This multi-functional integration means that a single installation effort delivers the combined capabilities of what would otherwise require separate systems, thereby reducing both installation complexity and costs while maintaining full functional versatility.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 integrated solution ensures comfortable interior temperatures and reduced fuel consumption by utilizing solar power for ventilation and dehumidification, even when stationary, while minimizing installation effort and costs.

Implementation Method 1

the outer skin (5) of the air conditioning system cladding (4) is designed as a solar cell for generating solar power

Methodology Applied
Scientific EffectSolar energy conversion: Photovoltaic Effect

Data Source

PatentEP2821266B1Air conditioning system for installation in the external area of a motor vehicle, in particular bus air conditioning system on a bus roof
Publication Date: 2021.01.13 MAN TRUCK & BUS SE
  • EP2821266B1 patent drawingFigure 1~2

AI summary

The invention relates to an air conditioning system located in the exterior of a motor vehicle, in particular a bus air conditioning system (3) on a bus roof, comprising an outer skin of an air conditioning system housing (4), wherein the air conditioning system (3) includes a cooling device with a compressor for a refrigerant cycle. According to the invention, the outer skin of the air conditioning system housing (4) is designed as a solar cell (5) for generating solar power or is at least partially covered with solar cells (5). The air conditioning system (3) also includes a ventilation and exhaust device for the vehicle interior (10) with at least one electrically driven fan unit (6, 7), and the at least one fan unit (6, 7) of the ventilation and exhaust device is operated directly or indirectly by the generated solar power.