Venetian blinds can help reduce heating, cooling and lighting costs.
Getting the energy balance of a building right requires a holistic approach to building design to ensure products and systems work in harmony to maximise the benefits. Venetian blinds can help to reduce heating and cooling loads and maximise daylight.
The problem |
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Most buildings have already been built. Old energy efficient buildings need high energy inputs to keep the temperature at an optimum. New highly insulated buildings are prone to overheating. |
The solution |
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Using Venetian blinds in buildings can help to reduce heat gain in the summer, heat loss during winter and control light levels and harvest natural light. |
The evidence |
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Building modelling conducted by the National Energy Foundation (UK) using Energy Plus on a model office has highlighted that internal shading by a venetian blind could save 10% of HVAC energy and a roller screen up to 23%. If fitted externally, the savings in HVAC energy were 43% and 47% respectively. |
During summer, Venetian blinds is particularly effective at preventing the solar radiation from reaching the glazed surfaces; internal blinds can also contribute to reducing solar energy especially if a reflective finish is applied on the window-facing side. Blinds also decreases the fraction of solar radiation in the short-wave infrared range (780-2500nm) that is absorbed and re-irradiated as thermal (long-wave infrared) radiation into the building and can significantly reduce the need for mechanical space cooling if coupled with cross-ventilation strategies.
During the colder months, blinds can provide night time insulation if fully closed overnight and maximise solar gains if left opened during daylight hours. A control strategy should be put in place rather than delegate its adjustment to the occupants.
Winter or summer, automation plays a key role, with a range of sensors and control systems that continuously monitor the environment and adjust, as may be required, the position of awning.