Tintable Window Control for Glare and Daylight Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrochromic windows, despite advances in technology, have not realized their full commercial potential due to various issues such as inefficient control of tint levels for occupant comfort and energy conservation, particularly in managing direct glare and radiant energy.
Innovation Solution
The development of control logic and systems that determine appropriate tint levels for electrochromic windows based on occupant comfort and energy considerations, using modules that account for sunlight penetration, calculated irradiance, and actual radiation levels, with a pulse width modulator to adjust the tint levels dynamically.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the window is darkened to reduce direct glare and radiant energy, then occupant comfort is improved, but natural lighting is reduced
Solution Approach 1:
The window system dynamically adjusts its tint level in real-time based on sensor inputs (sunlight detection, occupancy sensors) and environmental conditions. The control system modulates the electrochromic material's optical properties continuously rather than using fixed states, allowing optimization of both glare reduction and natural lighting transmission.
Solution Approach 2:
The system implements zone-based control where different portions of the window can have different tint levels. Sensors detect glare conditions in specific areas and apply localized tinting only where needed, preserving natural lighting in areas without glare issues while still providing comfort where required.
2Loss of energy
If the window is darkened to reduce radiant energy, then energy consumption is reduced, but natural lighting is reduced
Solution Approach 1:
The system incorporates sensors that continuously monitor radiant energy levels, occupancy, and natural lighting conditions. This feedback loop allows the control system to make real-time adjustments to the window tint, optimizing the balance between energy reduction and maintaining adequate natural lighting based on actual environmental conditions rather than predetermined schedules.
Solution Approach 2:
The electrochromic material's optical parameters (transmittance, reflectance) are dynamically changed in response to environmental conditions. The system adjusts the degree of darkening as a continuous variable rather than discrete steps, allowing precise control over the trade-off between radiant energy reduction and natural lighting transmission based on real-time sensor data.
3Illumination intensity
If the window is lightened to provide natural lighting, then illumination intensity is improved, but direct glare increases
Solution Approach 1:
The window system dynamically adjusts its tint level in real-time based on sensor inputs (sunlight detection, occupancy sensors) and environmental conditions. The control system modulates the electrochromic material's optical properties continuously rather than using fixed states, allowing optimization of both glare reduction and natural lighting transmission.
Solution Approach 2:
The system implements zone-based control where different portions of the window can have different tint levels. Sensors detect glare conditions in specific areas and apply localized tinting only where needed, preserving natural lighting in areas without glare issues while still providing comfort where required.
4Illumination intensity
If the window is lightened to allow sunlight penetration, then natural lighting is improved, but energy consumption increases
Solution Approach 1:
The system incorporates sensors that continuously monitor radiant energy levels, occupancy, and natural lighting conditions. This feedback loop allows the control system to make real-time adjustments to the window tint, optimizing the balance between energy reduction and maintaining adequate natural lighting based on actual environmental conditions rather than predetermined schedules.
Solution Approach 2:
The electrochromic material's optical parameters (transmittance, reflectance) are dynamically changed in response to environmental conditions. The system adjusts the degree of darkening as a continuous variable rather than discrete steps, allowing precise control over the trade-off between radiant energy reduction and natural lighting transmission based on real-time sensor data.
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 solution effectively balances occupant comfort by reducing direct glare and energy consumption by optimizing tint levels in electrochromic windows, ensuring they meet energy-saving standards while providing sufficient natural lighting.
Implementation Method 1
Electrochromism is a phenomenon in which a material exhibits a reversible electrochemically-mediated change in an optical property when placed in a different electronic state, typically by being subjected to a voltage change.
Implementation Method 2
Tungsten oxide is a cathodic electrochromic material in which a coloration transition, transparent to blue, occurs by electrochemical reduction.
Data Source
AI summary
Methods of controlling tint of a tintable window to account for occupant comfort in a room of a building. Some methods include receiving weather feed data from one or more weather services (or other data sources) over a communication network, determining a weather condition based on the weather feed data, and determining a tint level for the tintable window based on the weather condition and based on whether a current time is within a time delay period at sunrise or sunset.