Resource Efficiency and the Built Environment. Could Green Building be the answer?

Transcription

1 11 Resource Efficiency and the Built Environment. Could Green Building be the answer? Dr. Eng. Maritza VARGAS Ph.D. Environmental Economics Applied Look around for a moment, note all the objects that surround you: the screen staring at you, your desk, lamps, electronic devices, furniture, walls, ceiling, flooring, décor. If you look further, outside the room you are in, you may see buildings, streets, highways, parks: a city. You are actually looking at the built environment. Now, if we think about the materials composing that man made environment, we realize that everything comes from nature, and indisputably, everything returns to nature, therefore, to sustain our lifestyles and to keep aiming for economic growth, it is inexorable to modify our current patterns of production and start managing the natural resources wisely and efficiently. Energy, Water, Land, Natural Resources, Materials Built Environment Natural Environment Solid waste, Land contamination, Pollution, Air emissions, Water effluents and discharges Focusing on buildings, the land where they are built on and all construction materials come from non-renewables resources, with the exception of wood. Concrete, steel, aluminium, metal allies, cupper cables, stones, minerals, ceramics, glass, polymers, plastic, chemical paintings & coatings, artificial fibres, rocks like granite and marble, etc. are all derived from natural resources that need high energy processes for extraction and production, generally leaving behind a series of environmental impacts and pollution. More importantly, they come from finite, non-renewable resources, so one day they will finish. However, since most of these materials are abundant - like rocks, stones, cement, metals and silica - we have the tendency to think that their supply will never end and consequently, we misuse them and only the market value constrains their consumption.

2 12 We know the price of everything and the value of nothing Taking granite as example, one of the most popular rocks in buildings and showrooms. It is a beautiful igneous rock, commonly used because of its attractive appearance, durability, resistance and a hardness that is larger than steel s. Igneous granite is made of solidified lava that took millions of years to form; the S-type granite comes from melted sedimentary rocks that accumulated and underwent great pressure and temperature for larger periods of time. The use of resources is interlinked Undoubtedly, the three most frequently used, and most important resources for the human being are land, water, and energy. Land is our heritage; it is our responsibility to care of it for the next generations, so development must aim to enhance the surrounding environment instead of degrading it. Land is used to build our cities, to extract, mine and harvest all natural resources, and is also affected by the emissions and waste produced by most economic activities. The use of resources is strongly interlinked. Energy and water consumption is entwined with every life cycle stage of goods and services as shown in the following evidently, these interdependencies must be well understood when setting targets for resource use. A single target for a resource type might influence the use of other resources since all are related. However, we keep refurbishing and building new constructions with a short lifespan in mind, and with no hesitation at the moment to choose the new kitchen countertop or the contemporary bathroom; very few people think about the real value of this precious rock. While selecting the colour of the granite, not many people think about the time taken for nature to create it, the energy used for the extraction of the rock, the impact of the quarries on the environment, and the air pollution during fabrication. After some years of use, the beautiful countertop will be replaced and, in most cases, will go to a landfill as Construction and Demolition Waste (CDW). As Oscar Wilde once said, We know the price of everything and the value of nothing. Envirocities emagazine

3 13 The metal industry requires large amounts of energy and water for production Waste And Soil Degradation Water Pollution Discharges Air Pollution Ghg Emissions The majority of GHG emissions and from energy and transport Waste are misplaced natural resources Water and air emissions effect human health directly MATERIALS Fossil Fuels Minerals Metals Biomass Most fossils fuels are used for energy generation, but 5-9% are used for plastic, chemicals and fertilisers ENERGY Fossil Fuels Nuclear Renewables BUILDINGS Land use and land use change has an important role in climate change WATER Agriculture Electricity production Industury Maintenance of the built infrastructure requires 60-90% of construction minerals LAND Agriculture Wood Supply Natural Areas Built-Up Land Over 30% of water is used for cooling purposes in electricity generation Energy is needed to pump groundwater, desalination and tret wastewater

4 14 Energy and Water Energy and water consumption are indeed important, the lack of any these resources would lead to crisis and catastrophes in any part of the planet. It is widely know that the world is suffering an immense dependency on energy, and unequivocally, all projections show that the same trend will continue in the future. Development is accompanied by energy consumption to feed economic growth, mass industry, technology, and services. Energy is a fuel for life; it is indispensable to meet our most basic needs of living healthily, working and enjoying life. Additionally, the world population is growing at an incredible pace, adding more pressure to energy security. We were 1 billion habitants in 1800, approximately 2 billions in 1924, we reached 7 billions in 2011 and we are expected to be 9 billion habitants in Today, half of the population lives in urban centres being accountable for almost 60% of the global electricity consumption. The rate of urbanization during the next years will keep growing particularly in Asian developing countries. The hydrosphere, the Earth s outer liquid envelope (our water world), is concentrated almost entirely in the oceans; 97,5% of the planet s water is saline. The volume of freshwater resources is about 2.5% of the total volume. Of these, 68.9% is in the form of ice and permanent snow cover in mountainous regions, glaciers and in the Antarctic and Arctic regions. 30.8% is stored underground in the form of groundwater which constitutes to about 97% of all the freshwater potentially available for human use. Freshwater lakes and rivers hold an estimated 0.3% of the world s freshwater. Thus, the total usable freshwater supply for ecosystems and humans is less than 1% of all freshwater resources, and only 0.01% of all the water on earth (Gleick, 1993; Shiklomanov, 1999). In addition, the lack of freshwater in some areas increments the demand of energy use, this is especially the case of the Gulf region, where freshwater supply is not widely available and water needs to be desalinised to supply the population demand. Source: Igor A. Shiklomanov, State Hydrological Institute (SHI, St.Petersburg) and United Nations Educational, Scientific and Cultural Organisation (UNESCO, Paris), Envirocities emagazine

5 15 Green Buildings Considering the importance of the efficient use of resources, keeping in mind that most of them are finite and non-renewable; understanding that population growth represents higher demand of energy, water and natural resources, and acknowledging that cities and its buildings are among the major consumers of energy and resources, it is essential that we look for ways to reduce urban centres consumption without diminishing the quality of the services provided. In other words, we need to focus on Resource Efficiency to be able to deliver the required supply of energy, water and resources to our increasing population. Green Building is exactly about that. Taking a holistic approach through the whole life cycle of the buildings, from planning, designing, construction, operating and decommissioning. Green Building aims to connect the needs of the population - resource, energy and water efficiency - with issues such as site, climate, orientation of the building, waste management, thermal and lighting comfort, while enhancing the environment and the quality of life of its habitants, optimizing all these aspects in harmony. The multiple benefits of this integrated approach make Green Building a better option for the future, compared to conventional construction and operation. For example, improving the insulation using better windows and sealed doors reduces energy consumption, and consequently requires smaller HVAC equipment. Water efficiency saves energy, so by installing efficient water fittings we are also contributing to overall energy efficiency and security, while simultaneously helping to reduce green house gases and harmful air emissions that worsen the air quality and jeopardize the public health. Most designers and energy codes prioritize in strategies to save energy during the building operation, because it is the life cycle segment that consumes more energy. But a truly Green Building should also include the environmental impacts associated with the entire process from extraction, manufacture, transportation, assembly, and end of life disposal of building materials. Certainly, Green Building is one answer to aim for Resource Efficiency in the Built Environment. Evidently, it is not the only one, but it is a starting point to ensure that future generations will have the same opportunities of development we are having now. Green Building answers the call of Resource Efficiency towards sustainability. References: 1. Assessment of resource efficiency indicators and targets, Annex Report European Commission, DG Environment, UNEP, UNESCO and State of Hydrological Institute, February 2008