المبنى الأخضر في الأردن – نافذة جديدة على البيئة

في  دول العالم المتقدم , أصبح الحوار الذي ينافس السياسة و القضايا المجتمعية هو البيئة . أصبحت البيئة محط أنظار الجميع الان بعد سنين طوال من السعي وراء التكنولوجيا و التطور و إهمالها بشكل ملحوظ . إن مفهوم البيئة لم يعد مقتصرا على النظافة و توفير المياه فحسب , بل أصبحت الدول و القارات تتنافس في مجال انتاج الطاقة النظيفة ( طاقة الرياح , الشمسية , الطاقة المائية , طاقة الحرارة الأرضية , طاقة المد و الجزر و طاقة الكتل الحرارية ) وذلك بعد الجزم بإمكانيتها في  تأمين طاقة يمكن الإعتماد عليها في شتى الميادين و بشكل رئيسي بدلا من الطاقة النفطية التي تعتبر طاقة قابلة للنفاذ السريع .

في بداية الأمر انحصر تطبيق المشاريع الخاصة في مجال توليد الطاقة النظيفة و اعتماد مبدأ " المباني الخضراء "  في الدول المتقدمة فقط , كأوروبا و أمريكا الشمالية حيث الإمكانيات و المساحة الواسعة و تقبلهم لهذه الفكرة بشكل سريع , نظرا للوعي و الثقافة الجيدة في تلك المنطقة  .

ما هو المبنى الأخضر

المبني الأخضر هو المبنى الذي يراعي الاعتبارات البيئية في كل مرحلة من مراحل البناء، وهي التصميم، التنفيذ، التشغيل والصيانة، والاعتبارات الرئيسية التي تراعي تصميم الفراغات وكفاءة الطاقة والمياه، وكفاءة استخدام الموارد، وجودة البيئة الداخلية للمبنى، وأثر المبنى ككل على البيئة.الفرق الرئيسي بين المباني الخضراء والمباني التقليدية هو مفهوم التكامل، حيث يقوم فريق متعدد التخصصات من المتخصصين في البناء بالعمل معا منذ مرحلة ما قبل التصميم إلى مرحلة ما بعد السكن لتحسين خواص الإستدامة البيئية للمبنى وتحسين الأداء والتوفير في التكاليف.

الأبنية الخضراء في الأردن

بالحديث عن مفهوم المبنى الأخضر  في الأردن , فإن انتشاره لم يكن ذو رواج كبير و لكنه بدأ يلقى اهتماما منذ الاربع سنين الماضية . وفكرة أن تقنع المواطن و المؤسسات الحكومية و الخاصة بفوائد المبنى الأخضر كانت من المستحيلات في بداية الأمر .

مفهوم المبنى الأخضر يحتاج للدعم كي يشعر الجميع بأهميته حيث أنه سيقدم فوائداً مالية و بيئية للأفراد الأردنيين , و منها :

الفوائد الإقتصادية

البناء الأخضر سوف  يحفز صناعة حديثة في الأردن لمواد وتكنولوجيات  جديدة تلزم في عمليات  البناء. مما قد يوفر فرص عمل جديدة و يحسن هذه الصناعة في الأردن لما لها من أهمية في المستقبل . من المرجح ارتفاع أسعار النفط مستقبلا . فبالتالي ستساعد الابنية الخضراء  على الحد من استهلاكه و تقليص التكاليف المتعلقة بالكهرباء و الوقود .

الفوائد البيئية

ترتيب المملكة هو الحادي عشر من حيث أفقر البلدان في مصادر المياه لذلك فإن فائدة وجود مبان  خضراء سيوفر الكثير من ناحية المياه و شحها العام . المورد الشمسي في المملكة ضخم  حيث انها تتمتع ب333 يوما شمسياً أي ما يعادل 8 ساعات مشمسة في اليوم الواحد من السنة, و بالتالي فإن أنظمة التسخين الشمسية التي تستعمل في المباني الخضراء ستكون ناجحة و فعالة  .رفع كفاءة استخدام الطاقة في المباني من خلال اختيار مواد وأساليب العزل الأنسب .

كيف نعزز فكرة البناء الأخضر في الأردن ؟

تعزيز الوعي حول بناء مجتمع أخضر و أهميته للفرد و المجتمع .

فرض قوانين رسمية تعنى بأمور البناء الخاصة للمباني الخضراء .

تطوير القدرات و الإمكانيات التي من شأنها دعم مشاريع المباني الخضراء في الأردن , أي المساعدة في توفير المواد الخام و المساحات و ما إلى ذلك من السبل التي تعزز تمكين فكرة المبنى الأخضر بسهولة في الأردن .

التحديات التي تواجه الأبنية الخضراء في الأردن

هناك العديد من مهندسي البناء و المعماريين في الأردن ليس لديهم خبرة و معلومات كافية حول كيفية بناء و تصميم أبنية خضراء .

المواطنون قد لا يقتنعون بأن البناء الأخضر قد يساهم في توفير المياه و الكهرباء فلن يغامروا ببنائه .

المواطنون قد لا يفضلون التصاميم المحصورة للأبنية الخضراء من ناحية ترتيب الغرف و الاماكن .

في الأردن ليس هناك صناعة قوية لمواد البناء الخاصة بالمباني الخضراء , وفي حال الحاجة لها يتم استيرادها لكن بأسعار باهظة جدا .

وضع الأردن البيئي الان 

الأردن حاله كحال أي دولة تقع في منطقة الشرق الأوسط , ما زال موضوع الإهتمام بقضايا البيئة بالنسبة لمجتمعه أمر رفاهي لا يسمن و لا يغني من جوع , لكن مع تقارب العوالم و اتساع دائرة التواصل , تحركت مجموعات بيئية عدة قاموا بتطوير  انفسهم من هواة و متطوعين غير منظمين إلى منظمات و جمعيات و مجالس بيئية تسعى جادة لتطوير الوضع في الأردن . اصبح هناك جمعيات و منظمات تعنى بالبيئة الاردنية و بشكل جدي , و هناك مشاريع تقام على ارض الواقع كمشروع الخلايا الشمسية و مشاريع توفير المياه في شتى مناطق المملكة و لكن بتفاعل بطيء من المجتمع المحلي .

*في 11/اكتوبر/2009 تم إعلان أول جمعية مهنية غير ربحية غير حكومية تعنى و بشكل متخصص بمفهوم الأبنية الخضراء في الأردن وهي المجلس الأردني للأبنية الخضراء Jordan GBC  , و يضم المجلس مجموعة من المهندسين و الباحثين المهتمين بمجال البيئة المستدامة و الطاقة المتجددة و ترسيخ و تطبيق فكرة المبنى الأخضر بشكل جدي في الأردن , كما  تضم بعضويتها شركات وخبراء من مختلف الأعمال والتخصصات المرتبطة بتصميم المباني وتزويدها وإنشاءها في الأردن .

 و بصدد العمل على مشاريع توسيع هذه الفكرة , كان نشاط الجمعية واضحا فقد  وقع المجلس الاردني للأبنية الخضراء ومشروع الوكالة الأمريكية للإنماء الدولي اتفاقية منحة تنفيذ برنامج يهدف الى رفع كفاءة استخدام الطاقة من خلال تشجيع مالكي ومطوري الأبنية الجديدة على إدخال تطبيقات عملية وأساسية عند التصميم والتنفيذ. أما الخطوة الأقوى في تطوير هذا المفهوم كانت في نهاية عام 2013 حيث انضم المجلس الأعلى للابنية الخضراء إلى التحالف العالمي الجديد للمدارس الخضراء، ليصبح عضوا مؤسسا  في الائتلاف، والتي تعمل على توجيه المدارس والمجتمعات المحلية إلى تغيير جذري في طريقة تربية الطلاب على المفاهيم والمبادئ الخضراء.

كما قام هذا المجلس بالتنسيق مع وزارة التربية و التعليم الاردنية بعقد دورات تثقيفية و توعوية حول مفهوم المدارس الخضراء .ربما تعتبر خطوات الأردن نحو تطوير بيئي ملحوظ  بطيئة و منهكة , و لو تحدثنا بشكل خاص عن مفهوم " المبنى الأخضر " فإن الأمر قد يزداد صعوبة و تحديات , لكن بما ان هناك جمعيات و مؤسسات و أفراد يسعون لتطوير الوضع البيئي فهناك نافذة جديدة سوف تفتح للأجيال القادمة تطل على مستقبل أردني جديد  مخضرّ .

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Airports: Viable Places for Green Initiatives

Bahrain-airportCan airports ever be green? This is an overwhelming concept in a carbon-driven, and carbon-intensive industry. The reality is that air travel is often the only realistic option for the movement of both people and cargo in the current lifestyle and demands encompassed with time constraints. This is especially critical for the island nation of Bahrain that is so heavily dependent on air travel in terms of food security. With over 90% of all goods: perishable and manufactured, imported into the nation, this carbon-intensive industry is not going to disappear.

Airports themselves, may only contribute 5% to the carbon emissions attributed to the aviation industry, never the less, airport infrastructure could ensure a lowering of emissions, especially nitrogen oxide levels [1]. The International Air Transportation Association (IATA) has statistical evidence of improved fuel efficiency and better CO2 performance over the past 15 years[1]. It is viable for airports to reduce the nitrogen oxide levels around airports by developing ground transportation infrastructure for transferring passengers and deploying employees across the airport terminals, ground handling of personal baggage and commercial cargo, as well as the catering services, in a more eco-friendly mode of transportation.

Scope for Green Airports

Airports are viable places for adoption of green initiatives. A significant portion of the emissions are from vehicle transportation onsite at the airport is from moving employees and passengers between terminals and aircraft carriers. Plus all the freight movement, personal baggage and inflight catering and servicing. To secure adequate food products for Bahrain, the greater part of all food produce that is available on the market (93%) is flown in on a daily basis. The dependency on aviation is long-term but the ground handling is an option for energy efficient initiatives.

There is an opportunity to move from fossil fuel vehicles to those running on clean such as hybrid, electric, bioethanol, biogas or hydrogen-fueled vehicles. As road transportation is a major contributor of carbon dioxide and nitrogen oxide emissions, greener, cleaner vehicles are a desirable consideration for protecting a fragile environment.

Role of Environmental Awareness

Greater awareness of renewable energy sources is necessary before developers can even start to appeal to the business sector to adopt viable alternatives of transportation energy. New airport development and expansion projects need to assess the feasibility of alternative mode of transportation which in turn will require electrical charging locations as well as hydrogen filling stations [2]. This can also be marketed to eco-friendly rental companies to avail themselves of green initiatives.

Freight and delivery corporation could also avail themselves of alternative power sources as petrol subsides are reduced over the coming years. Ultimately, sustainable energy sources will become more attractive. Together, a sustainable transportation model along with other sustainable life-cycle models will all help reduce the carbon footprint of the airport industry.

Airports are considered ideal sites for promoting electricity-powered vehicles because one has a captive audience. If the options are already determined for the clients, the clients experience the use of electric cars in a win-win situation.

Rapid Increase in Passenger Flow

During the month of November, 2016, almost 674,000 passengers passed through the Bahrain airport [3]. There was over 8,500 total aircraft movement and almost 20,000 pieces of cargo and mail in the 30 day period. (Data source: Ministry of Transportation and Telecommunications). Based on the November data, the numbers could be extrapolated out for a 12-month period with over 8 million passengers per year, over 100,000 total aircraft movement and 240,000 pieces of cargo and mail.

Similar information based on the official Airport Councils International (ACI) statistics from the World Airport Traffic Reports for the 10-year period from 2005 to 2015 [3]. The reports indicate a yearly average of 7.8 million passengers with over 95,350  total aircraft movements and over 304,000 metric tons of cargo. The steady increase in usage of airport facilities [4] is driving the modernization plans for the Bahrain International Airport to be designed for an annual passenger flow of 14 million persons [5].

Heathrow Airport – An Upcoming Role Model

Heathrow Airport in London handles more than 76 million passengers each year. Heathrow is already conducting trials for electric buses and personal electric cars, as part of a sustainable model, which requires a major input for developing recharging infrastructure. Such a large airport in the heart of a metropolitan centre has the advantage of a well developed public transportation infrastructure.

Electric vehicles at Heathrow Aiport

Electric vehicles at Heathrow Aiport

Both travelers and employees use the public transport systems which allows the advanced planning in other sustainable green technology for other transportation systems. Passenger car parks as well as company car parks have charging points for electric cars. The airport strategic plan is to have all cars and vans electric rather than fossil fuel powered by 2020.

Perspectives for Bahrain

Aviation transportation is vital for Bahrain’s survival and daily operations. Therefore, a eco-friendly infrastructure is a viable option for implementing green technology in the form of onsite transportation. However, the modernization of the Bahrain International Airport has limited its eco-friendly inclusion to ground service equipment such as the transformer substations, pre-conditioned air systems and pop-up units and the 400Hz power supply system all contracted to Cavotec Middle East [5].

This is one step towards achieving the International Civil Aviation Organization (ICAO) decision to implement a global carbon offset for the aviation industry. It would be great to see the Ministry of Transportation and Telecommunications reach out to other green initiatives for the modernization of the national airport.

 

References

1. Can airports be green? http://www.airport-technology.com/features/feature100283/

2. How airports uniquely placed to boost the adoption of electric cars. https://www.theguardian.com/heathrow-sustainable-mobility-zone/2016/nov/21/airports-uniquely-placed-boost-adoption-electric-cars-emissions-reduction?CMP=ema-1706&CMP=

3. Airports Council International, World Airport Traffic Reports, 2005, 2006, 2007, 2008, 2009, 2020, 2011, 2012, 2014 and 2015. Traffic by Calendar Year, Official ACI Statistics. https://en.wikipedia.org/wiki/Bahrain_International_Airport

4. Bahrain International Airport witnesses a 25% increase in passenger movement http://www.mtt.gov.bh//press-centre/press-releases/210914

5. New Passenger Terminal Building, Bahrain International Airport, Manama, Bahrain http://www.airport-technology.com/projects/new-passenger-terminal-building-bahrain-international-airport-manama/

Progress of Green Building Sector in Qatar

There has been rapid progress in green building sector in Qatar with the emergence of many world-class sustainable constructions in recent years. With the fifth-highest number of LEED-registered and certified buildings outside the U.S., Qatar has valuable experience and inputs to offer on the system’s local relevancy and application. Various countries in the Middle East have been accredited with regards to the LEED system. Of these buildings, 65 per cent (802) are located in the UAE. Qatar is ranked second on the list, with 173 green buildings, followed by Saudi Arabia (145), Lebanon (25) and Egypt (22).

 

Qatar’s Green Building Rating System

Qatar has developed established its own assessment called Global Sustainability Assessment System (GSAS), formerly known as the Qatar Sustainability Assessment System (QSAS) system specifically developed for the State of Qatar. GSAS is billed as the world’s most comprehensive green building assessment system developed after rigorous analysis of 40 green building codes from all over the world. The assessment criterion takes into consideration various categories related to sustainable development and its impact on environmental stress mitigation. Each criterion elucidates the requirements of reducing environmental stress and a score is then given to each criterion based on the level of compliance. QSAS is assessed on the following eight categories; urban connectivity, site, energy, water, indoor environment, materials, management and operations and cultural – economic values. Qatar has incorporated QSAS into Qatar Construction Standards 2010 and it is now mandatory for all private and public sector projects to get GSAS certification. 

 

Qatar Green Building Council

The Qatar Green Building Council (QGBC) was established in 2009 to promote sustainable growth and development in Qatar through cost efficient and environment-friendly building practices. The organisation aims to support the overall health and sustainability its environment, people and economic security in Qatar for generations to come. As one of the 30 members of the LEED roundtable, the Qatar Green Building Council endeavour to prioritise factors such as environmental conditions and its influence on green buildings. For instance, in arid regions such as Qatar, improving a building’s water efficiency in order to reduce the burden on local supply is a priority.

 

Benefits for Qatar

Sustainable development has been identified as one of the top priorities in Qatar’s National Development Strategy. The ultimate objective of green buildings is to reduce the overall impact of the built environment on human health and the natural environment. This can be promoted by using water, energy and other resources more efficiently as well as ensuring occupant health and improving employee productivity. Green buildings can bring a variety of social, economic and environmental benefits for Qatari residents. Through rainwater harvesting, greywater recycling and renewable energy systems, green buildings can promote water conservation, energy management as well as climate change mitigation. Moreover, this can also bring along sizable reduction in operation costs and offer long-term savings. Finally, sustainable buildings in Qatar can improve overall health of the occupants by tackling common issues such as insufficient air circulation, poor lighting and temperature variances. Green buildings emphasize natural ventilation which creates healthier and more comfortable living environments.

 

Qatar National Convention Center – A Shining Example

The Qatar National Convention Center, located in Doha, has recently been accredited for its approach to environmental stress mitigation. The 177,000 square meter structure has been commended for its recognition as one of the world’s most iconic energy-efficient convention centers built to date. The building has 3,500 square meters of its roof areas with solar panels, contributing 12.5% of the building total electrical consumption. Other contributors include, LED lighting, air volume systems and carbon dioxide monitors. The building has also gained recognition for being one of Qatar’s first environmentally sustainable structures which has even been given the gold certification standards under the LEED system equivalent to 6 stars on the QSAS.

 

Conclusion

Structures such as the Qatar National Convention Center will be a benchmark for all future green structure in Qatar. With an increase in population along with an ailing environment, it is absolutely necessary that we begin to take an approach that is suitable to the demands of our time. It is heartening to see that Qatar has recognised the importance of green architecture and lucrative benefits associated with it. 

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Effective Energy Management for Businesses

energy-management-middle-east-businessesMiddle East has been witnessing a rapid increase in energy consumption due to high degree of industrialization, high standards of living and exponential increase in population. Infact, the level of primary energy consumption in the Middle East is among the highest worldwide.  These factors have made businesses in Middle East to realize that effective energy management is not only good for the businesses but also an essential requirement.

In recent years, many businesses in the Middle East have come up with dynamic strategies to achieve immediate reduction in energy consumption. This trend towards effective energy management is expected to continue to grow in the region in the coming years on account on changing regulations and growing awareness on energy conservation.

Ingredients of Effective Energy Management Plan

For an energy management plan to succeed, the entire organization including its employees and management team, should be committed to the implementation of energy management strategy whose main elements are:

  • Goal-setting: how much energy reduction do you want to achieve?
  • Number-crunching: how much energy do you consume?
  • Identifying energy-guzzlers: What are major consumption units and what measures can be taken to reduce consumption
  • Technology and automation: Smart metering, schedule-based lighting, occupancy sensors, HVAC control and latest technological innovation provides an active approach to energy management
  • Continuous review and management: Regular performance monitoring is essential to check the progress towards your energy-saving goals. 

Hurdles to Overcome

​Lack of incentives to reduce energy consumption is a major hurdle faced by businesses in the Middle East. In the GCC region, electricity is usually provided at heavily subsidized rates which fail to provide the motivation to the consumer to reduce energy consumption. Most of the commercial buildings in the Middle East consume huge amount of energy in the form of HVAC, lighting, ventilation etc., and there is a real need to make such buildings ‘ energy smart’ in the real sense of the word.

An energy smart building - Siemens headquarters at Masdar

An energy smart building – Siemens headquarters at Masdar

Role of Technology

Technology plays a vital role in reducing energy consumption as energy-savings are not limited to power consumption by HVAC, lighting or ventilations, but also encompass optimization of energy use, building infrastructure, supply chain networks, product design, transportation networks etc. Businesses in the Middle East may strive for energy-smart buildings, smart grid systems and renewable energy sources (like rooptop solar and biogas systems) to improve their long-term sustainability and more effective cost-management.

Green Roofs in MENA – Prospects and Challenges

Green roofs are emerging technologies that can provide a wide range of benefits to communities interested in enhancement and protection of their environment. The major benefits of green roofs are reducing energy use as well as air pollution and greenhouse gas emissions, enhancing stormwater management and water quality, decreasing heat island effect by regulating temperature for the roof and the surrounding areas and providing aesthetic value and habitats for many species.  

According to a 2013 MENA renewable energy status report, the Total Primary Energy Supply (TPES) in Middle East and North Africa has reached about 800 million tons of oil.  This equates to a 15% increase in energy demand since 2007. Increased energy consumption in the region is due largely to population growth, with related increases in demand for liquid fuels and electricity for domestic use and devices, heating, cooling, and desalination of water.  With heating and cooling being a reason for the increasing demand on fossil fuels, there is enormous opportunity for investment in green roofs as a way to stabilize or reduce energy consumption in the MENA region.  

Enhancing Stormwater Management and Water Quality

Stormwater is rainwater and melted snow that hits impervious surfaces and runs off into streets, lawns, sidewalks, and other sites. The main concern with stormwater is it can pick up debris, chemicals, dirt, and other pollutants and flow into a storm sewer system or directly to a lake, stream, river, wetland, or coastal water. In many places around the world, including MENA region, anything that enters a storm sewer system is often later discharged untreated into a nearby waterway polluting the same waters we swim, fish, and drink from.

In addition, stormwater runoff can cause flooding and an overflowing of sewer sanitary systems causing serious water quality impairments. In developing countries like Morocco and Algeria, where countrywide stormwater management and municipal waste management systems are deficient, stormwater runoff is a big problem. Rainwater flows from roofs straight onto streets carrying things like petrol, household garbage, bacteria, fertilizers and pesticides to nearby receiving waters.

According to an EPA study, green roofs are capable of removing 50% of the annual rainfall volume from a roof through retention and evapo-transpiration. By reducing the amount of impervious surfaces within a developed zone, green roofs reduce the amount of stormwater runoff.   Also, because green roofs absorb water, they delay the time at which runoff occurs, resulting in decreased stress on sewer systems at peak flow periods.

For conventional non-living roofs with a slope of 2%, a 96% runoff rate is observed.  On the other hand, intensive green roofs may have as low as a 15% runoff rate.  The benefits green roofs have regarding stormwater runoff could be amplified by more green roofs in a close-knit area and using green roofs with a deeper substrate layer. Nevertheless, if implemented, countries in the MENA region in which stormwater management systems are not in place could greatly benefit from the use of green roofs to help reduce hazardous runoff and subsequent contamination of water supplies. 

Decreasing Urban Heat Island Effect

Since the built environment tends to be constructed from materials that are impermeable and non-reflective they tend to absorb a significant proportion of the sun’s radiation and release it as heat. Because urban areas are densely populated with buildings, they tend to be hotter than the surrounding areas, a phenomenon known as heat island effect.  Urban heat islands have many negative impacts such as an in increase energy demand for cooling, an increase in air pollutants and greenhouse gas emissions, and impaired water quality.

The heat island effect causes internal temperatures of buildings to rise which subsequently increases the demand for air-conditioning to moderate the buildings internal temperatures.  This in turn leads to higher emissions from power plants, as well as increased smog production as a result of warmer temperatures.  Additionally, hot rooftop surfaces transfer their excess heat to stormwater causing the runoff water to be much warmer than the streams, lakes, and other waterways it enters.  In many cases dealing with this rapid change in temperature causes stress to aquatic ecosystems.

Urban heat island effect is especially worrisome for areas like Middle East and North Africa, where out of a population of 300 million, 170 million people reside in urban areas. Furthermore, according to UN projections the MENA population will reach 430 million by 2020, of which 280 million are expected to be urban.  In order to combat the potential for the heat island effect in the MENA region, communities can utilize green roofs. 

The vegetative surfaces of green roofs utilize a relatively large proportion of the absorbed radiation in the evapo-transpiration process and then release water vapor into the air which helps to cool air temperatures.  Additionally, the shade provided by trees and other shrubbery greatly helps to reduce the rooftop temperatures and the overall heat island effect. 

Roof Lifespan

Rooftop vegetation moderates the factors that accelerate a rooftops breakdown such as extreme temperatures, UV radiation, and cold winds, thus dramatically expanding the life of a roof.  According to a study in Germany, a vegetated roof on average can be expected to prolong the service life of a conventional roof by at least 20 years. The result of this is not only cost savings to the building’s owner but also a reduction of landfill wastes. 

Habitats for Species

One of the more altruistic aspects of green roofs is the creation of wildlife habitats. Green roofs can provide habitat (food, shelter, water and breeding grounds) for many different species. Because of their high density, cities severely restrict green space and threaten or destroy habitats so the creation of such green space assumes particular importance in these areas.  Urban habitats are often seen as too degraded and depauperate to support biodiversity. 

Various recent studies in Europe have indicated that green roofs in large cities have high potential as habitat for species negatively impacted by land-use changes. For example, in Basel, Switzerland, surveys of birds, spiders and beetles on green roofs found high diversity levels for all groups, including many species considered rare or threatened.

For modern Middle Eastern citiies like Dubai, Jeddah, Cairo, Beirut and Tehran, creation of habitats for species could be very valuable.  Across the MENA region natural habitats are few and far, and green roofs can provide living space for plants and animals, especially for species such as invertebrates and birds. 

Aesthetic Value

Green roofs have the ability to significantly improve the beauty of buildings, the visual and environmental diversity which can have positive impacts psychological well-being. Studies across several countries have all shown the correlation between daily contact with nature and human well-being. In fact, the results of a large survey in the Netherlands showed that the amount of green space in the residential environment was positively related to the health condition people said they experienced in their daily life.

When people have contact with green space research has indicated a positive effect in levels of stress, health levels due to green space encouraging a higher level of use of the outdoor spaces, and mental well-being due to positive psychological effects plants and nature has on humans.

Current Scenario

While green roofs in Northern Scandinavia have been around for centuries, in North America green roofs are still a relatively new technology. In Europe, these technologies have become very well established mainly due to governments and legislatives financial support.  This support has led to the creation of a vibrant, multi-million dollar market for green roof products and services in Germany, France, Austria and Switzerland among others.

Currently, implementation of green roofs is rare in the MENA region.  However, there is a definite market potential as the benefits of green roofs address many of the major environmental concerns of this area.  Furthermore, the concrete architecture in the Middle East is ideal for a green roof implementation.  The structural soundness of concrete buildings has the potential to support the weight load of both intensive and extensive roofs. The swift progress of green buildings industry in the Middle East  promises a deeper penetration of green roofs in domestic as well as commercial constructions in the years to come.

However, one issue that may surface is that roofs are often fully accessible and are often used to dry laundry or to hold social events like weddings and other celebrations.  This may pose an issue for home owners if their green roof takes up too much of their roof to perform their daily functions.  An intensive roof may be more suitable for homeowners in this region as they lend well to daily visits and offer space to hold social functions.

Conclusion

Due to their extensive range of environmental and economic benefits, particularly their insulation and cooling properties, ability to significantly reduce rainwater runoff and urban heat island effect, as well as improve air quality and their value in promoting biodiversity and habitat in urban areas, green roofs have become important elements of sustainable and green construction in many countries.  While the green roof industry is growing in popularity, the industry is still young with many areas needing advancement.

The major barriers to green roof expansion in the Middle East include a lack of governmental support, high installation costs, lack of awareness and education about green roofs, and limited data quantifying green roof benefits.  However, with proper support these barriers can be easily overcome through research and innovation in design by the green roof industry. 

 

References

  1. After the Storm". (2013). 2013, from http://water.epa.gov/action/weatherchannel/stormwater.cfm#what
  2. Akbari, H. (2005). Energy Saving Potentials and Air Quality Benefits of Urban Heat Island Mitigation. 1-19. http://www.osti.gov/scitech/servlets/purl/860475
  3. Beattie, D., Berghage, R., Jarrett, A., O’Connor, T., Razaei, F., & Thuring, C. (2009). Green Roofs for Stormwater Runoff Control (pp. 81). National Risk Management Research Laboratory Office Of Research And Development: EPA.
  4. Bryden, J., Riahi, L., & Zissler, R. (2013). MENA Renewables Status Report. In L. Mastny (Ed.), (pp. 21). REN21 Secretariat, Paris, France.
  5. Colla, S. R., Packer, L., & Willis, E. (2009). Can green roofs provide habitat for urban bees (Hymenoptera: Apidae)? . Cities and the Environment 2(1), 1-12. http://digitalcommons.lmu.edu/cgi/viewcontent.cgi?article=1017&context=cate
  6. Dinsdale, S., Pearen, B., & Wilson, C. (2006). Feasibility Study for Green Roof Application on Queen’s University Campus: Queens University.
  7. Dunnett, N. (2006). Green Roofs For Biodiversity: Reconciling Aesthetics With Ecology. Paper presented at the Fourth Annual Greening Rooftops for Sustainable Communities Conference, Boston.
  8. Green Roof Benefits. (2013).   Retrieved 12/9/2013, from http://www.greenroofs.org/index.php/about/greenroofbenefits
  9. Hermy, M., Mentens, J., & Raes, D. (2006). Green roofs as a tool for solving the rainwater runoff problem in the urbanized 21st century? Landscape and Urban Planning, 77, 217–226. Retrieved from www.sciencedirect.com website: http://www.floradak.be/downloads/eng.pdf
  10. The Future of Green Roofs.   Retrieved 12/18/2013, from http://www.hrt.msu.edu/greenroof/future/index.html
  11. The social role of green space – health, education and enjoyment of life. (2005).   Retrieved 12/18/2013, from http://www.thesteelvalleyproject.info/green/intro/people-2.htm#well
  12. Urban Challenges in the MENA Region. (2013).   Retrieved 12/14/2013, from http://goo.gl/IT8rWo 
  13. What Is an Urban Heat Island? (2013).   Retrieved 12/14/2013, from http://www.epa.gov/hiri/about/index.htm

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Top Green Building Trends Worldwide

transparent-solar-windowsWith green building movement sweeping across the world, innovative technologies are being developed to keep pace with increasing shift towards sustainability. Integration of biodegradable, recycled, recyclable and renewable materials in the construction of buildings is attracting great attention worldwide. Natural paints, recycled steel, cellular concrete, clay bricks, wood, bamboo etc. are getting huge popularity in construction of green buildings.

Another interesting innovation is zero-energy building which utilizes solar cells/panels, wind micro-turbines, fuel cells and biofuels, among others, to meet electricity and HVAC requirements of the building. Likewise, net-zero-water-use buildings make use of water conservation systems to efficiently manage water consumption, rainwater harvesting, waterless toilets, greywater reuse, smart landscaping and on-site sewage treatment.

Low-emitting windows, coated with metallic oxide, to block sun’s harsh rays during summer and keep the heat inside in the winter are also gaining popularity. Such windows have the potential to significantly reduce heating and cooling costs of buildings.

According to Dubai-based green buildings expert Sunanda Swain, “Transparent solar window panels can also be incorporated into awnings, curtain walls, glass facade or as overhead glazing units.” She explains, “These increase access to direct sunlight while providing additional architectural benefits such as passive shading.”

Net Zero Energy Buildings rely on exceptional energy conservation and on-site renewable generation to meet energy requirements..

Net Zero Energy Buildings rely on exceptional energy conservation and on-site renewable generation to meet energy requirements..

Another promising innovation is in the form of cool roofs which is made of special tiles and reflective paints to reflect sunlight. Cool roofs have high levels of solar reflectance and thermal emittance, and help in reducing the heat island effect in urban habitats, especially in arid areas like the Middle East.

To sum up, green buildings can not only contribute towards environment protection but also bring loads of advantages to building occupants and users. Lower development costs, reduced operating costs, healthier indoor environment quality and less maintenance costs are major benefits associated with green buildings. To sum up, green building technologies can serve as catalysts for smart urbanization and sustainable development of urban centers, besides ensuring energy security, climate change mitigation, and opening new economic and job opportunities. 

Green Buildings Certification in MENA – Issues and Challenges

Green building rating systems are increasingly gaining attention in the building industry in the MENA region. During the last 15 years, there has been a regional trend in developing and applying green building ratings systems. In several countries such systems have been developed in an attempt to follow the international green movement. For example, the Pearl Building Rating System (PBRS) was founded in UAE in 2007, the Green Pyramid (GPRS) and ARZ Building Rating System in Egypt and Lebanon respectively were founded in 2008, the Edama was proposed in Jordan in 2009 and Qatar Sustainability Assessment System (QSAS) was founded in 2010. 

A new study compared four regional rating systems in the Middle East, in addition to LEED and BREEAM. The study found that the problem with most emerging rating systems is that they imitate the LEED or BREEAM rating systems and are not enough adapted to local environmental, cultural, historical, societal and economic context. Thus certification systems must be adapted to meet the needs of the Middle East regional climate, social, environmental and economic conditions.

The study, conducted in 2013, compared four rating systems (GPRS, SI 5281, QSAS and PBRS) and a cross analysis study was used to answer questions about the strength and weakness of the systems. The four systems use score point system for assessment. The four tools provide programs involving the building life cycle process – pre-design, design and post-design (occupation). There are many common criteria and categories between the four examined rating systems; such as limiting the consumption of energy and water in the building, improving the environmental quality in both indoor and outdoor, resources and material conservation, service quality, and site strategies. The four rating systems operate from an ecological foot print minimisation paradigm. At the same time, each rating system focuses on certain aspects more than the other ones according to the country’s local context. Surprisingly, there is no agreement on weighing the different environmental criteria.

Problems of Rating Systems

The study found that the examined rating systems are proposing theoretical models that needs to move to effective market implementation politically (government) and economically (NGOs & private sector). The rating systems require more adaptation to local and regional context. Rating systems should differentiate themselves from well-established rating systems.  For example, the study believes that water scarcity should be the most important category together with human wellbeing. Already LEED and BREEAM programs are considered the most fairly comprehensive in scope – from registration to calculation to building certification. In the case of the four rating systems, the initiation approaches were bottom down and not bottom up approaches.

Therefore, the uptake and market penetration is slow compared to LEED or BREEAM. In the four countries, there is no encouragement/engagement in the form of working out incentives or law enforcement to apply the four rating systems except for PBRS. In fact, each country in the region is looking to achieve those criteria individually. The entry of the LEED and BREEAM rating system into the Middle East property market coincided with increasing demand for regional and local ratings systems. As a result, different systems were developed under serious time pressure in the last ten years. The four compared systems are based on American and British standard. In the same time, there are currently no standardisation efforts working at local level to quantify and assess sustainability.

Towards Harmonised Systems

Green Building Councils in the Middle East will have a long way; they have to manage to position themselves as leaders promoting green buildings in the countries where they operate. By comparing and evaluating the four rating systems lesson could be learned and problem could be avoided. Therefore, the study author believes that a harmonised system within the Middle East would have distinctly better chances if the following issues are addressed:

Institutional Setting

Since the oil embargo of 1973, Western countries developed local codes and standards, which are revised annually, for the built environment. Those codes correspond to their context and are strongly linked to practice and buildings industry. However, in the four examined countries, the (b) local codes and standards are still not mature when compared to American or British ones. So there is a regulation problem on the institutional level. More importantly, (b) energy and water are heavily subsidized in most of the four countries.The comparison revealed that the certification rates are low and the feesstructure is very high (registration, certification, auditing).

Thus the whole political regulation landscape regarding resources efficiency is contradicting with the rating systems scope and objective. Therefore, it is important to address the (a) efficiency regulations and (b) subsidies policies on the institutional level and avoid the dependence on Western standards, codes and rating systems. This should be done through facilitating the adjustment and upgrading for the specification of environmental assessment factors in a dynamic, flexible and simple way.

Scientific Rigour and Priorities

Developing an assessment framework should be based on in-situ building performance research and technical knowledge. Technical rigour is very important in this case, for example setting benchmarks and measuring the performance. Furthermore, the investigated rating systems are located in hot climates, with scarce water resources which require a different approach and credits focus. Issues like solar protection, water conservation, life style, solar cooling and urban planning should be more strongly addressed in future developments. This includes advancing environmental footprint issues, like climate change.

Regionalisation

The assessment framework should suite the local context of each country in the Middle East, depending on its culture, issues, stakeholders, practices and institutions. Surprisingly, SI 5281 is the only rating system that was written in a native language, thus it is essential for each country, to design its own indicators to serve its goals in local language. This includes the development of local criteria to quantify the social part of sustainability that includes tradition and culture.

Providing a Platform

Multi-stakeholders should participate in developing rating systems, since they require participative and collaborative work process. Experts, designers, elected officials, working group, agency players, and others should be introduced as key participants in this process. The building industry should be encouraged to get into sustainable track to achieve a real transformation, regarding water and energy. There is a need to link those rating systems to grass root initiatives rather than developing them within academia or elite practicing companies.

According to the study, the examined certification systems need strong adaptation to meet the needs of the Middle East regional climate, social, cultural, environmental and economic conditions. Also there must be a harmonisation effort between regional rating systems aiming to develop and implement a common, transparent regional building assessment methodology. Otherwise, there will be a proliferation of immature systems without accumulated and unifying experience. 

Conclusion

There is still a long way before those examined systems examined become mature and widely usable.  Despite that the development of the examined rating systems is intended to facilitate the assessment of sustainable design in MENA; they fail to suit the local context culture issues, resources, priorities, practices and economic challenges. The GPRS, QSAS and PBRS systems neglect the interpretation of essential local sustainability measurements in their assessment set and normative standards. The study concludes that the existing rating system needs to increase the technical rigor and to put more weight on the most important categories, mainly water, IEQ, pollution and energy. The study suggests a number of recommendations to develop a harmonised green building assessment system in the MENA region. The usefulness of rating systems in the future depends on their flexibility and ability to measure the merits of buildings.

Note: The original version of the article can be viewed at this link.

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Green Building Trends in the Middle East

Siemens-MasdarThe Middle East region faces a unique set of environmental and socio-economic challenges in the form of water scarcity, harsh climatic conditions, ecological degradation and abundance of fossil fuels. Commercial and residential buildings in the Middle East consume more energy than those in other parts of the world, mainly on account of extremely hot weather, rampant use of glass exteriors and heavy reliance on air-conditioning. The Middle East building industry, in recent years, is actively trying to make widespread use of eco-friendly architecture, traditional building methods and sustainable construction practices.

Some of the other drivers for the progress of green buildings sector in the Middle East are carbon-neutral buildings, self-sustaining urban planning and cultural sensitivity incorporating traditional Islamic architecture. Many countries in the region are increasingly promoting energy efficiency as a means to achieve energy security which has catalyzed the local green buildings industry. As far as social reasons are concerned, improved health and greater productivity are the top reasons for companies going green in their construction.

Trends in the Middle East

In recent years, green building design has emerged as a top priority in the Middle East. The number of LEED-registered buildings has increased rapidly across the region, from 623 in 2010 to more than 1400 in 2015. United Arab Emirates is leading the pack with almost two-third share, followed by Qatar, Saudi Arabia and Egypt. Some of the prominent green buildings are Masdar Institute of Science and Technology (Masdar City), Climate Change Initiative Building (Dubai), Qatar National Convention Centre (Doha), King Abdullah University of Science and Technology (Jeddah) and World Trade Center (Bahrain). Siemen’s headquarters in Masdar City has the distinction of being the first LEED Platinum-rated office building in the entire Middle East. Msheireb Downtown Doha is regarded as the world’s first sustainable community, with more than 100 buildings targeting LEED Gold and Platinum rating.

Infact, the UAE has the fourth-largest stock of LEED-certified buildings outside the US at 3.1 million sq. meters. UAE also has the distinction of having the fourth-largest number of LEED-accredited construction professionals worldwide. Sunanda Swain, a leading Dubai-based green buildings expert says that, “Presently, the UAE has total cumulative gross square meters (GSM) of LEED- certified and registered spaces of 53.44 million and the total number of LEED-certified and registered projects are 910 (in comparison to 710 by June 2014)”. She adds, “In Abu Dhabi, over 700,000 square meters of real estate are certified by the Urban Planning Council under Estidama sustainability standards.”

Regional countries, such as Qatar and UAE, have come up with their own building sustainability standards and building laws to incorporate socio-economic, environmental and cultural aspects in modern architecture. Infact, Qatar's Global Sustainability Assessment System (GSAS) is billed as the world's most comprehensive green building rating system while Abu Dhabi's Pearl Rating System (Estidama) and Dubai’s Green Building Regulations has swiftly carved a niche of its own in global green buildings sector. Green Building Councils in United Arab Emirates, Qatar, Saudi Arabia, Jordan, Egypt etc. are proactively working to popularize the concept of green buildings in their respective countries.

Conclusion

Green buildings can not only contribute towards environment protection in the Middle East but also bring lots of advantages to building occupants and users. Lower development costs, reduced operating costs, healthier indoor environment quality and less maintenance costs are hallmarks of major benefits associated with green buildings. To sum up, Green building technologies can serve as catalysts for smart urbanization in the Middle East, besides ensuring energy security, climate change mitigation, and opening new economic and job opportunities. 

Green Roof Potential in Arab Cities

Urban green roofs have long been promoted as an easy and effective strategy for beautifying the built environment and increasing investment opportunity. The building roof is very important because it has a direct impact on thermal comfort and energy conservation in and around buildings. Urban green roofs can help to address the lack of green space in many urban areas. Urban green roofs provides the city with open spaces that helps reduce urban heat island effect and provides the human population on the site with a connection to the outdoors. However, we must differentiate between two types of urban green roofs and assess their adaptability to Arab cities. This article provides an insight on green roofs and roof farming in Arab cities.

What are Green Roofs

Green roofs are essentially sustainable and passive design features of vegetation surfaces applied to a waterproofing layer of a suitable conventional roof build-up in rainy climates. In rainy countries such as Austria, Germany and Belgium green roofs are recognized as a significant source-control feature,contributing mainly to storm water management and drainage control. Green roofs not only store water at roof level, but also reduce the run-off rate from the roof, which in turn reduces the underground drainage network requirements. It is also possible to use or harvest rainfall from a green roof, although the amount of rainwater that can be used may be reduced depending on the type of green roof implemented.

Generally speaking, there are no green roofs in hot arid climates. In Arabia it is hardly to find any examples of successful green roofs. According to European norms the minimum annual precipitation rate for a green roof should be more than 450-650mm. Therefore, it is impossible to grow a green roof in Cairo (26mm), Amman (276mm), Riyadh (20mm) or Dubai (10mm). Even coastal cities like Alexandria (190mm), Tunis (450mm) or Casablanca (425mm) witness extreme summers and drought periods that almost eliminates the sedum plants from recovery during the winter season. Facing these facts, there are many voices in Arabia that surprisingly continue pushing the idea of green roofs claiming to sustain it through artificial irrigation. An idea that make us lose the whole point of sustainability in an already water scarce region.

Unfortunately, across the Middle East there are large numbers of students, architects, clients and even researchers who have a wrong perception and a defective understanding of semantic of green roofs,which are essentially associated with the presence of renewable rain water. This is due to the unfamiliarity with word Green Roof in our region and the huge influence of the Northern imaged media. Moreover, there are many researchers who talk about the positive side effect of green roofsthat significantly save energy, enhance the thermal performance and comfort of buildings, particularly in terms of summer cooling, based on readings and studies made in countries with latitude higher than 40o with temperate or cold climates. What is missing here is local evidence based experimentation and practices that address green roof in the warm and hot climate not from a theoretical copy-paste approach.

The Real Problem

Arab cities suffer from serious problems that are similar to most other large cities in the developing countries. Among the most visible manifestations of the challenges posed by rapid urbanization are many environmental problems, such as pollution, dense urbanization, urban heat island effect and inversed greenhouse effect during winters. In fact, the dense concentration of automobiles and polluting buildings created a negative impact on the environment. In fact, the rapid urbanization not only created environmental problems but also economic problems. For example, air conditioners are running, over the whole summer period, trying to deliver an endless demand for cooling. This leads to increasing prices of electricity bills. This is due to the lack of energy codes, which means that roofs are without or with very poor insulation. Additionally, cities suffer from constant desert sand depositing together with disappearance of green spaces which lead to deprivation of open space.

During the last decade many Arab cities witnessed several times inefficient food production and distribution, inaccessibly high food prices and above all locally grown food, loaded with toxic contaminants. The fast-growing population and the failing government approaches to housing and spatial planning policies contributed to the growth off informal settlements within and around the center. For example, 8 million Egyptian live in informal settlements in Cairo with problems of unemployment, pollution, transportation, inadequate drainage and sewerage, and lack of usable urban open spaces. In Cairo, the amount of green space per inhabitant is roughly equivalent to 0.33 square meters per person (3.5 square feet), one of the lowest proportions in the world. Among the above listed problems stands out a common denominator. It is the building roof.

Roof Farming as an Alternative

Under the influence of the all those issues emerges the idea of roof farming. Urban roof farming has long been promoted as an easy and effective strategy for beautifying the built environment and increasing investment opportunity. Roof farming can help to address the lack of green space in many urban areas. Urban roof farms provides the city with open spaces that helps reduce urban heat island effect and provides the human population on the site with a connection to the outdoors. Challenged by environmental and pollution, Cities suffer from locally grown food, loaded with toxic contaminants that threat the health.

In the last couple of years, Cairo suffered from an inefficient production and food distribution and inaccessibly high food prices. The population explosion and the tendency to build on agricultural land have acted to limit the resources of city families and their access to healthy edible products. With a little effort and money, roof farming can contribute in improving the families quality of life and provide them with healthy food and raise their income, this is besides the environmental and aesthetical role it plays. For example, Cairo citizens and some governmental authorities acknowledged the problem of food contamination & distribution and are mapping measures and methods that can guarantee safe food.While it is not new, the notion of planting rooftops in Egypt has only recently been implemented. In the early 1990s at Ain Shams University, a group of agriculture professors developed an initiative of growing organic vegetables to suit densely populated cities of Egypt. The initiative was applied on a small scale; until it was officially adopted in 2001, by the Food and Agriculture Organization (FAO).

There are several case studies that represent successful projects implemented by different non-governmental organizations (NGO), public institutions and private civil initiatives. For example Ibn Kassir foundation, in Al-Zawya Al-Hamra, Cairo, created a roof farm from wooden containers (barrels) with plastic sheets filled with peat moss or perlite used as substrates. The drainage is driven through small plastic hoses to buckets. This system is producing leafy crops such as parsley, radish, and carrots. A square meter using this method would cost around 400 Egyptian pounds (LE).

Finally, in many Arab cities, where many environmental social and economic problems exist, a beam of light emerges to contribute in solving many of these interrelated problems. Planting our roof with different kinds of vegetables and fruits or even any kind of green plants will change lots of things. It is certain that roof gardening and farming have measurable qualitative and quantitative benefits. The techniques for implementation are simple and doable and above all cost efficient. However, no roof gardens can be created without the knowledge of the factors affecting the creation and design. The most important factors are the climate, the constructional and economic factors.

Regarding green roofs, we shall only address this issue based on experimental and monitored cases. More importantly, a vision is required to be drawn together with long term strategy, adopting the holistic approach of roof farming and providing support and sustainability. It is this holistic approach that can solve many problems of different background and aspects, and can contribute to improving the quality of life of the dense Arab cities. By exploitation of such roofs, their development and planting; a reasonable ratio of green areas can be reached in the near future. A ratio of 4 square meters per person can be provided once the suitable green framing roofs have been developed and exploited.

Source: Attia, S., Mahmoud, A., (2009) Green Roofs in Cairo: A Holistic Approach for Healthy Productive Cities, Conference Proceeding on Greening Rooftops for Sustainable Communities, June, Atlanta, USA http://orbi.ulg.ac.be/handle/2268/167604

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مقدمة عن زراعه الاسطح الخضراء

تعتبر زراعه الاسطح من التكنولوجيا التي توفر مجموعة كبيرة من الفوائد الملموسه وغير الملموسه للمجتمعات المهتمة بتحسين وتعزيز بيئة جيدة.للأسقف الخضراء فوائد عديدة فهي تعمل على تنظيم حرارة المبنى ,فتقوم بتدفئته خلال الشتاء و تبريده خلال الصيف كما تساهم فى تقليل مياه الامطار المتسربة من الاسطح، ذلك لأنها تعمل كإسفنجة ماصة للمياه و في الوقت نفسه تستفيد النباتات من هذه المياه.

 كما تقوم الأسقف الخضراء على تقليل التلوث حيث تعمل كفلتر لتنقية الهواء. ومن فوائد الأسقف الخضراء قيامها  بدور هام فى تقليل الضوضاء و التى تعتبر من مشاكل العصر الحديث خاصة فى المدن. كما يجب ان لا  ننسى أن للأسقف الخضراء فوائد اقتصادية عديدة فهى تزيد من عمر المباني حيث تعمل كعازل حراري بحجبها أشعة الشمس عن أسطح المبانى كما تقلل من تكاليف تكييف الهواء خلال الصيف و التدفئة خلال الشتاء.

ما هي الاسطح الخضراء

النظم المستخدمة لزراعة أسطح المباني يجب ان تكون نظاماً خفيف الوزن لا يسبب حمولة زائدة علي المبني، كذلك يجب ان لا يحدث تسريب للمياه من النظام لسطح المبنى حتى يتم الحفاظ على المبنى بصورة جيدة ولفترة طويلة. و قد وجد أن الزراعة بدون تربة بأنظمتها المختلفة وأشكالها المتنوعة هي الاسلوب الامثل لزراعة السطح.

الاسطح الخضراء ممكن ان تتكون من اشجار, نباتات او شجيرات. وعمق وكثافه الطبقة المنبته للزراعه تنقسم الي نوعين مختلفين.

فالاسطح الخضراء ممكن ان تكون مكثفة او قليله الكثافة علي نطاق واسع. فالاسقف المكثفة تكون اكثر سمكا (اكثر من 15 سم عمق), وهي سماكة تسمح لنمو مجموعه متنوعه من النباتات والاشجار والشجيرات. ولكنها ثقيله علي السطح ومكلفه اكثر, وتتطلب المزيد من الصيانة والري.

والنوع الاخر يغطي طبقة خفيفة من الغطاء النباتي وذات سماكة اقل من 15 سم. وهي مخصصه للشجيرات والاعشاب التي لا تتطلب عمق كبير داخل التربة للنمو.

يستخدم نظام ترابيزات المراقد لانتاج المحاصيل التي لا تحتاج إلى حيز كبير لنمو جذور النباتات  مثل  المحاصيل  الورقية  كالجرجير،  الفجل،  البقدونس،  الكسبرة  والشبت.  كذلك يمكن باستخدام هذا النظام زراعة العديد من النباتات الطبية والعطرية والتي تستخدم في البيوت بكثرة كالنعناع، الزعتر، الريحان, وغيرهم.  

والاسطح الخضراء علي مساحات واسعه وكثافه بسيطة يتم صيانتها مرتين سنويا عندما تحتاج التربه للترطيب والتسميد, فلها ميزة ان استدامتها ذاتية .

بيئة الزراعة المستخدمة

يجب ان تتوافر في بيئة الزراعة المستخدمة فوق الاسطح عدة مواصفات يمكن ان تلخص بما يلي :

1.      ان توفر البيئة الرطوبة اللازمة لنمو الجذور.

2.      ان توفر البيئة التهوية اللازمة لنمو الجذور.

3.      ان لا  تحتوي البيئة علي مواد ضارة او سامة.

4.      ان تكون البيئة خالية من المسببات المرضية.

5.      ان تكون البيئة خالية من الاملاح .  

6.      ان تكون البيئة خالية من بذور الحشائش.

7.      أن تكون البيئة خفيفة الوزن.

8.      أن تتميز البيئة بسهوله تنظيفها و تعقيمها.

9.      سهوله توفر البيئة, مع سهوله عمليات النقل.

10.  ان تكون تكلفه البيئة معتدلة.

ويوجد العديد من المواد التي يمكن استخدامها كبيئة للزراعه فوق الاسطح. وتنقسم الي قسمين رئيسين هما: بيئات عضوية مثل بيئة سرس الارز. او البيئات غير العضوية مثل بيئة البرليت. ويمكن ان تسنخدم البيئات السابقة بصورة منفردة او تخلط معا للوصول الي افضل توليفه تلائم النباتات المزروعه.

اما بالنسبة للاشكال المختلفة لنظم مزارع البيئات فوق الاسطح, فهناك نظام الترابيزات المراقد وتستخدم للنباتات التي لا تحتاج الي حيز كبير لنمو الجذور. نظام ترابيزات الاصص وتسنخدم للنباتات التي تحتاج الي  حيز كبير نسبيا حتي تنمو الجذور مثل الطماطم. وهناك نظام لانتاج بعض اشجار الفاكهة فوق الاسطح مثل البراميل سعه 60 لتر لانتاج بعض الاشجار مثل الليمون.

بسبب الحمل المنشأ من استخدام الاسطح الخضراء الكثيفه فانها تستخدم بشكل اكبر في المباني التجاريه. حيث ان المباني التجارية اكثر تحمل لكونها اقوي من الناحية الخرسانيه, فانها تستطيع تحميل الاوزان الزائدة عنها في المباني السكنية.

بمجرد تجهيز التربة ووضع النباتات المطلوبة وترطيب تربتها, فان السطح المزروع ممكن ان يزن 150 بوند/القدم المربع. ويراعي لخلق جو اخضر وطبيعي للزائريين. ان ييكون هناك اماكن جلوس, مناضد, كراسي وممرات. الامر الذي يخلق بيئة من الطبيعه والهدوء.

والاسطح الكثيفة ذات الاشجار الاكبر حجما تساعد اكثر من النباتات علي الهدوء والاستراخاء, وخلق بيئة قريبة من المتنزهات والحدائق.

وعلي جانب اخر فان الاسطح الاكثر انتشارا والاقل كثافة تكون افضل للمباني السكنية و المدارس. فهي سهله التركيب والصيانة وممكن ان تضاف الي المبني بعد بدء الاسكان بدون تخوف من الاحمال الزائدة. ايا كان نوع النباتات او الشجيرات المستخدمة فانه يمكن اضافة وزن 10-35 بوند/القدم المربع, لاجمالي أحمال السطح. الحشائش والنباتات غير المستهلكة لكثير من الماء من الانواع التي تجد استحسان للزراعة فوق السطح وذلك نظرا لاستخدامها القليل للماء وجذورها القصيرة.

 ومن أهم فوائد الاسطح الخضراء انها صالحة للمباني القديمة والحديثة.

 والانظمة المستخدمة للزراعه يمكن ان تكون وحدات بطبقة صرف وطبقة فلترة من القماش وطبقة انبات بنوع معين, وشبكة ري وصرف متشابكة. والنباتات المستخدمة والتي تكون مسبقة التجهيز خارجيا, البوتقات المستخدمة التي تكون منفصله عن النظام او مركبة جزء منه. وهذا النظام يسمح بتكوين النظام بشكل منفصل.

تختلق التقارير  التي توضح تكلفة النظام المتسع والاقل كثافه للتربه المستخدمة ليكن في المتوسط لزراعه النظام المتسع ما بين 8-20 دولار/ للقدم المربع. وبالنسبة للنظام الكثيف مابين 15-50 دولار/القدم المربع. وبالمقارنة للاسطح التقليدية المزروعه والتي تكون في المتوسط 16 دولار/القدم المربع وقد يعلو عن ذلك في التكلفة. ولكن بالرغم من ذلك فان ما توفره الاسطح الخضراء من فوائد بيئية وجمالية وصحية هي اكثر بكثير من التكلفه المتوقعه للتنفيذ.

فوائد الاسقف الخضراء

الاسطح الخضراء لديها القدرة علي خفض متطلبات الطاقة بطريقيتين:

امتصاص الحرارة واعتبارها عازل حراري للمبني. فاضافه طبقه من التربة والنباتات الي السطح يزيد طبقة العزل الحراري علي السطح. فالاسطح هي اكثر الامكان التي تفقد الحرارة الداخلية في الشتاء وتزيد سخونة المبني في الصيف. الاسطح الخضراء يمكن ان تقلل من كمية الطاقة اللازمة لتلطيف الحرارة داخل المبني وبالتالي الحد من متطلبات الطاقة والتي لها تاثير ايجابي علي نوعية الهواء وتخفيض نسبة تلوثه. كما ان الاسطح الخضراء ممكن ان تقلل من انبعاثات غازات الاحتباس الحراري وثلوث الهواء المرتبطة بزيادة نسبة ثاني اكسيد الكربون في الجو. وتعتبر محطات الطاقة والمعروف انها مسببة لانبعاثات ثاني اكسيد الكربون تكون الاسطح الخضراء حلا ايجابيا علي تقليل هذه الانبعاثات عن طريق تحويله الي اكسجين مما يساعد علي تحسين نوعية الهواء في البيئة المحيطة.    

 

ترجمه: هبة احمد مسلم- دكتور الهندسة البيئية. باحث في الشئون البيئية. معهد الدراسات والبحوث البيئيةجامعه عين شمس.

مدرس بالاكاديمية العربية للعلوم والتكنولوجيا والنقل البحري-  مصر.

التحكم في البيئة والطاقه داخل المباني.

هندسة الميكانيكة- وكيل محرك دويتس الالماني بمصر. 

للتواصل عبر hebamosalam2000@gmail.com

    

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نصائح لتحسين نوعية الهواء داخل المباني

يعتبر تلوث  الهواء الداخلي  واحد من أهم المخاطر البيئية على الصحة العامة في جميع أنحاء العالم ,نظرا لتزايد  عدد من الأمراض المرتبطة  بنوعية  الهواء  داخل  المبنى . وقد وجدت الدراسات أن تركيز الملوثات في الأماكن المغلقة الداخلية   أعلى بكثير مما هي عليه في البيئة الخارجية ، تتراوح  الزيادة  من  مرتين إلي خمس مرات ، وأحيانا مائة مرة أعلى من مستوي  الملوثات في الهواءالطلق. وبما  ان معظم الناس يقضون  80٪ إلى 90٪ من حياتهم في الأماكن المغلقة ، فان  نوعية الهواء الداخلي له اأثر جوهري على الصحة العامة.

انخفاض جودة الهواء في الأماكن المغلقة يمكن أن يؤثرعلى نوعية الحيا ة  لشاغل المبنى ، وزيادة المخاطر الصحية وزيادة المسؤولية لمالك  البناء ،وانخفاض إنتاجية شاغلي المبني ويقلل من قيمة إعادة البيع له . و سوء نوعية الهواء في الأماكن  المغلقة يمكن أن يسبب "مرض متلازمة البناء "،وهي حالة طبية مرتبطة بسوء الحالة  الصحية والتغيب عن العمل.

وهناك العديد من العوامل المسببة بما هو معروف بمرض متلازمة البناء علي سبيل المثال لا الحصرتصميم المبنى بشكل غيرلائق للغرض منه، وعدم كفاية التهوية ، بعض المكونات المسببة لتواجد المركبات العضوية المتطايرة من الأثاث و السجاد والدهانات ومواد الطلاء و منتجات التنظيف والتنفس مع سوء نوعية الهواء في الأماكن المغلقة .

الجسيمات المحمولة مثل الالياف  الزجاجية اوالغبار ،عث الغبار و العفن والبكتيريا وحبوب اللقاح ووبر الحيوانات يسهم أيضا في سوء نوعية الهواء في الأماكن المغلقة . وهناك مؤشر لتحدد جودة الهواء في الأماكن المغلقة وتشمل مجموع الجسيمات ،مجموع المركبات العضوية المتطايرة ،والفورمالديهايد ،وثاني أكسيد الكربون  (CO2) ، وأول أكسيد الكربون  (CO) ، والأوزون (O3)، درجة حرارة الهواء والرطوبة النسبية  (RH)  .

في منطقة الشرق الأوسط، , معظم الناس يعيشون في بيئات مغلقة ومكيفة الهواء لفترات  طويله. و مع النمو السكاني السريع ،و زيادة عدد المركبات على الطريق ،و ارتفاع  مستوي درجة الحرارة ،وزيادة أنشطة البناء عن  أي وقت مضى ،ووجود عواصف  رملية موسميه  بشكل  دائم , و تركيز ملوثات الهواء في المنطقة هي من بين أعلى المعدلات  في  العالم. ويعكس  جودة  الهواء  في  البيئة الداخلية أيضا نوعية الهواء و التلوث في البيئة الخارجية.

ان نقل الملوثات من الهواء الخارجي  الي  الأماكن المغلقة يمكن أن يؤدي الي تأثيرات صحية خطيرة . وبالإضافة لذلك كالعديد من مصادر الملوثات في الأماكن المغلقة الموجودة في مواد البناء وموا دالتنظيف والعفن الداخلي  للتكيفات  والمعدات ونمو البكتيريا ،والانبعاثات من المفروشات .

نصائح لتحسين جودة الهواء في الأماكن المغلقة

تتأثر نوعية الهواء في الأماكن المغلقة بتركيز ملوثات الهواء في الهواء الخارجي وكذلك مصدر التلوث في الأماكن المغلقة ،كما  ان  سمة البناء وعادات أهل  المكان  له  تاثير علي نسبة الملوثات. ويمكن تصميم بناء مناسب ونظام  تهويه ميكانيكي واستراتيجيات مكافحة وكذلك تغيير السلوك العام  سوف  يؤدي  بدوره  الي تحسين جودة الهواء في الأماكن المغلقة والصحة والراحة والأداء والإنتاجية من شاغلي المبنى. هناك مجموعة من الاستراتيجيات لتحسين جودة الهواء في الأماكن المغلقة  يمكن حصرها  في  التالي :

التصميم المناسب :بناء الغلاف الخارجي ،والتوجه،ومكان لشفط الهواء ،موقع أنظمة التهوية الميكانيكية يمكن أن تسهم في جودة الهواء في الأماكن المغلقة. وبالتالي ،ينبغي النظر في هذه العوامل خلال مرحلة تصميم المشاريع للسيطرة على المصدر الرئيسي للملوثات للمبنى بأكمله.

التهويه  الميكانيكية  لكامل  المبني :تصميم نظام التهوية والذي  يتناسب مع  حجم  المكان  وعدد  الشاغلين  والنشاط القائم  يمكن  ان  يوفر  هواء من الخارج  للداخل  بشكل  مناسب . في معظم أنظمة تصنيف المباني الخضراء ،ويتم اتباع معاييرالصناعة مثل مواصفات ASHRAE 62أو التهوية وجودة الهواء الداخلي المقبولة عموما .

نظام  خلط  الهواء :  استخدام مزيج من أنظمة التهوية الميكانيكية والطبيعية في المباني ،مثل أنظمة التحكم الآلي للنوافذ  والنوافذ قابلة للفتح  و الغلق ، يمكن أن تساعد في الحفاظ على جودة الهواء في الأماكن المغلقة.

إدارة نوعية الهواء خلال مراحل البناء: خلال مرحلة البناء, قد تتولد انواع من العفن بسبب التعرض لمواد البناء مع الرطوبة. الغبار والجسيمات يمكن أن تتراكم بسهولة على مواد البناء إذا لم تكن محمية. نوعية الهواء خلال فترة التشييد يمكن حمايتها من خلال حماية مواد البناء من الغبار والجسيمات والرطوبة بانواع الاغطية المختلفة والتي تناسب كل المركبات باختلاف انواعها.

مرشحات الهواء عالية الكفاءة :فلاتر تمنع انتقال المركبات العضوية المتطايرة في الهواء الخارجي والغبار ،الجسيمات والأوزون الي الداخل.ان استخدام فلتر الجسيمات مثلMERVعالية الترشيح  يمكن  ان  يكون  من المرشحات الأكثر فعالية في تصفية الغبار والجسيمات من الهواء الخارجي الي الداخل.

جدول الصيانة لمعدات التكييف والفلاتر :تراكب الغبار علي فلاتر التنقية يمكن أن يسبب تهيجا  للحساسية . وبالتالي ،جدول الصيانة المناسب والمنتظم يمنع هذ اأن يحدث.

استخدام المواد ذات  الانبعاثات المنخفضة: استخدام المواد التي تحتوي على  مركبات  عضوية  متطايرة بنسب منخفضة مثل السجاد ،مطاط الأرضيات ،مواد الأرضيات والسيراميك والبلاط  و اي مواد مالئة للفراغات الارضية أو مانعات التسرب والمواد اللاصقة الأخرى.  أيضا مواد البناء الداخلية والتي  تحتوي علي مادة الفورمالديهايد  بنسبة منخفضة ,يمكن أن تكون مفيدة  لجودة البيئة الداخلية.

طرد الملوثات من المبني: طرد الملوثات في الأماكن المغلقة اسلوب جيد في المباني قبل الإشغال و يساعد علي استبدال الهواء الداخلي الملوث مع الهواء الخارجي النقي.

برنامج التنظيف الاخضر: اختيار مواد التنظيف والمصنوعة من المواد ذات الانبعاثات المنخفضة وتوظيف برنامج التنظيف الأخضر للحد  من التعرض للانبعاثات.

جهاز مراقبة ثاني أكسيد الكربون: تثبيت اجهزة مراقبة CO2 في نظام التهوية ودمجها لتنظيم إمدادات الهواء النقي وفقا لطلب شاغلي المبنى. وبذلك فانه  بزيادة نسبة ثاني اكسيد الكربون داخل المكان يزيد معدل تدفق الهواء الخارجي .

 

ترجمه:

هبة احمد مسلم- دكتور الهندسة البيئية. باحث في الشئون البيئية. معهد الدراسات والبحوث البيئيةجامعه عين شمس.

مدرس التحكم في البيئة والطاقه داخل المباني.

للتواصل عبر hebamosalam2000@gmail.com

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Introduction to Green Roofs

Green roofs are emerging technologies that can provide a wide range of tangible and intangible benefits to communities interested in enhancement of their environment.  Green roof development involves the construction of a vegetative layer on top of a human-made structure or building adding green space to areas that would otherwise be unused.  The major benefits of green roofs are reducing energy use as well as air pollution and greenhouse gas emissions, enhancing stormwater management and water quality, decreasing heat island effect by regulating temperature for the roof and the surrounding areas and providing aesthetic value and habitats for many species. 

What are Green Roofs

Green roofs mainly consist of a vegetation layer consisting of trees, plants, and other shrubs, a substrate layer where water is retained and in which the vegetation is secured, and a drainage layer which helps to evacuate excess water. The depth of the substrate layer is how the two main types of green roofs are differentiated.

Green roofs can be intensive or extensive. Intensive roofs are thicker, more than 15 cm deep, which allows for the growth of a wider variety of plants including trees and shrubs.  However these roofs are heavier, more expensive and require more maintenance and irrigation.  Extensive roofs, on the other hand, are covered in only a light layer of vegetation, less than 15 cm, and are primarily made up of shrubs, low-growing sedums, and herbs.  Unlike the plants on an intensive green roof, the extensive vegetation is typically self-sustaining apart from the bi-yearly maintenancewhen the beds need to be weeded and fertilized.

Because of their weight and function intensive roofs are usually used on commercial buildings.  Commercial buildings tend to be made out of concrete and can support heavierweight loads than traditional homes.  Once the plants are installed and the soil is moist these rooftop green spaces can weigh as much as 150 pounds per square foot. They also tend to have more room to include benches, tables, greenhouses, fountains and walkways that travel between different features of the green roof and provide space where people can interact with the natural surroundings. Intensive roofs tend to be more attractive than extensive roofs and can offer people a place to relax, eat or work in park-like settings.

Extensive roofs on the other hand because of their low weight tend to be more often suitable for residential type buildings or sheds and barns.  Extensive green roofs are the simplest to install and are very often added to existing roofs. Depending on the source you look at these roofs may add 10 to 35 pounds per square foot to a roof’s load.  Drought-tolerant plants and grass are the most common used vegetation on an extensive green roof due to their low water requirements and the shallowness of their roots.

Unending Benefits

Green roofs can be placed on both old and new buildings.The green roof system can either be modular, with drainage layers, filter cloth, growing media and plants already prepared in movable, often interlocking grids, or loose laid/ built-up where each component of the system may be installed separately.  Reports vary on installation costs but on average extensive green roof range between $8 and $20 per square foot and intensive green roofs range between $15 and $50 per square foot.  This compared to a traditional roof installation which averages about $16 dollars per square foot the green roof installation costs tend to be much higher. Although a higher installation cost is required, the green roof undoubtedly offers more benefits than a traditional roof may offer.

Green roofs have the potential to reduce energy demands two ways: absorbing heat and acting as insulators for buildings.  Adding a layer of soil and plants to a roof adds insulation to the building it covers.  Since roofs are the site of the greatest heat loss in the winter and the hottest temperatures in the summer, the greater insulation offered by green roofs can decrease the amount of energy required to moderate the temperature of a building.

Furthermore, reducing the demand for energy consequently reduces air pollution.   By lowering air conditioning demand, green roofs can decrease the production of associated air pollution and greenhouse gas emissions such as CO2, coming from power plants.  Additionally, because plants through photosynthesis convert atmospheric CO2 into oxygen, the plants on green roofs can help filter harmful noxious gases in the air and reduce CO2 emissions in the atmosphere.  

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