I had gone through the internet to find out how glass can help us from achieving the max. energy conservation while giving the max. benefit. following are the points which clearly gives in brief why glass should be adopted in India for external facade treatment.
• Day-lighting - The use of glass brings in lot of light that helps in giving a high amount of natural day lighting instead of depending solely on artificial lighting thus reducing considerably electricity consumption.
• Blending interiors with exteriors (Views) - Glass facades give a spectacular view of the outside world from the cozy interiors.
• Recyclability - Glass being recyclable satisfies the important parameter of being a “Green” building material.
• Achieving energy efficiency - High performance glass helps in controlling the solar and thermal heat in the interiors and helps to maintain the temperature at its minimum best and in turn helps to tone down the air-conditioning expenses.
• Innovative application - Being very flexible building material glass helps to satisfy and capture an architect's utmost imagination in its shape and form.
• Controls noise: Double glazed glass facades help in achieving a high degree of acoustic comfort by keeping away noise penetrating from the exteriors to the interiors thus ensuring a calmer atmosphere inside.
• Self Cleaning: The future belongs to self-cleaning glass which keeps itself clean on its own and brings out an ever sparkling effect.
Role of Glass in Green Architecture
• The lux level from direct sunlight is around 1,13,000 Lux.
• The lux level in shade is around 9,000 Lux.
• Brightly lit interiors which are conducive for working require 500 Lux.
High Performance Glass helps in cutting down excessive glare and brings in abundant natural light thus reducing the dependence on artificial lighting.
Energy Efficiency
In climatic conditions like India, 80% of the total heat gain is due to direct solar radiation and the rest is due to temperature difference between the exteriors and interiors. Thus to reduce the overall Relative Heat Gain (RHG) in tropical climates, it becomes necessary to curtail the incoming solar radiation by the use of glass with high performance solar “control” coating. Contrary to this, in cold climates the emphasis is on glass with low-emissive coatings to reduce the rate of heat loss from interiors to exteriors.
The total heat gain is measured in terms of Solar Factor and U-value and is expressed as a sum of these two components.
Solar Factor :
Heat gain on the inside of the building due to direct solar radiation incident on glass is measured through the solar factor of glass.
Solar Factor: It is the sum of percentage of incident solar energy directly transmitted and incident solar energy absorbed and re-emitted inside.
U-Value
Heat gain due to temperature difference is expressed by U-Value of a glass.
Looking forward for more study and knowledge in this area.
