Are green walls the next big thing in environmental tech? - By E - The Environmental Magazine |
|
Green walls (also known as biowalls, vertical gardens or vertical vegetated complex walls) are wall structures partly composed of or filled in with growing plant matter. More than just easy on the eyes, green walls work like green roofs by filtering air and water, soaking up carbon dioxide and helping lessen the heat island effect of urban areas while reducing air conditioning costs in their host buildings.
The self-proclaimed creator of the vertical garden concept, French botanist Patrick Blanc, pioneered the use of hydroponic cultivation techniquesplants grow in an irrigated mineral nutrient solution without the need for a soil substrateto create large green wall installations in both residential settings and within larger public structures and even office buildings from Singapore to San Francisco and points in between.
Blancs installations start by placing a metal frame on a load-bearing wall or structure. The frame supports a 10-millimeter-thick PVC plate, upon which are stapled two 3-millimeter-thick layers of polyamide felt. These layers mimic cliff-growing mosses and support the roots of many plants, he says, adding that a network of pipes and valves provides a nutrient solution of dissolved minerals needed for plant growth. The felt is soaked by capillary action with this nutrient solution, which flows down the wall by gravity.
The roots of the plants take up the nutrients they need, and excess water is collected at the bottom of the wall by a gutter before being re-injected into the network of pipes: The system works in a closed circuit. Plants are chosen for their ability to grow in this type of environment and depending on available light.
Each vertical garden is a unique wall composition of various types of plants that has to take into account the specific surroundings of the place in which it is created, says landscape architect Michael Hellgren, who founded the firm Vertical Garden Design in 2004. It is not only the colorful interplay between the plants on a green wall that is fascinating, but also the appearance of the wall itself, which changes daily.
Hellgren, who has designed and implemented large green walls in his home country of Sweden as well as in Spain, Portugal and Italy, among other locales, sources plants for his projects from various climate zones around the world. His favorites are so-called lithophytes: plants that can grow on rocks, branches and tree trunks without necessarily being rooted in soil. Among other things these climbing plants have the enormous advantage of their roots acting as excellent natural drainage on the wall, he adds.
While large vertical gardens are surely impressive, critics question the sustainability of such endeavors, given the energy inputs needed to run the pumps and other equipment used to maintain proper nutrient and air flows, and the emissions caused by the manufacture and transport of specialized materials. Also, larger green walls need more water than rain alone can provide, and thus dont necessarily save water. But as the field matures, practitioners are finding wider arrays of plants to choose from that are better at taking care of themselvesand scaling back on inputs and supporting machinery with the hope that one day many of the walls will be self-sustaining gardens that cleanse our dirty air and compromised storm water.
Ref: http://bit.ly/vcy2OB |
|
รายการข่าวอื่นๆ มีดังต่อไปนี้ :
|
Empire State Building Strikes Gold. |
|
LG Electronics Unveils Multi V III, Its Most Advanced VRF Technology HVAC System. |
|
Office workers reap healthy spin-offs from efficient building design. |
|
Toshiba Introduces Voice-Controlled AND Energy-Efficient Air Conditioner |
|
International Green Building Conference 2011 to Explore Innovative, Sustainable, and Actionable Green Building Solutions Especially for the Tropics and Sub-Tropics |
|
Green building experts shop for ideas at Singapores first eco-mall |
|
3rd floor of building L a model of green design |
|
Global Air Conditioning Systems Market to Reach 144.30 Million Units by 2015, According to New Report by Global Industry Analysts, Inc. |
|
2022 World Cup organizers determined to beat the heat. |
|
IN TIME OF DROUGHT, RICE UNIVERSITY SAVING 12 MILLION GALLONS OF WATER A YEAR BY REUSING AIR CONDITIONING CONDENSATION, OTHER INITIATIVES |
|
Taipei 101 is Worlds Tallest Green Building |
|
Effective office spaces |
|
Tips from the repair man, how to keep your AC running smooth |
|
Hospitals, Physicians Hustle to Prepare for Hurricane Irene |
|
Local green building rules a better fit. US standard will be harder to achieve |
|
Gardens are growing on green roofs around town |
|
Dublin Building Wins Award For Being Environmentally Friendly |
|
All govt offices to keep air-cond temperature at 24ºC from now |
|
Broken air conditioning has students, teachers sweating |
|
Agency: 440 sought hospital care for heat illness: Wichita, KS USA |
|