ADVANCING THE COURSE OF CIRCULAR ECONOMY
THROUGH GREEN BUILDINGS
LEARNING OBJECTIVES
 Understanding the concept of Circular Economy
 Discovering how water efficiency & Net zero water in green buildings
aligns with circular economy’s objective of water use reduction that can be
used in the BD+C, O+M, ID+C, and HOMES LEED Rating Systems
 Getting to know how renewable energy use and net zero energy in green
buildings drives the course of circular economy regarding use of renewable
energy which can apply to all LEED Rating systems.
 Understanding how to minimize and achieve net zero waste in BD+C,
ID+C and O+M building projects.
INTRODUCTION
Circular Economy and green buildings are both connected with sustainable
development. They both operate in a system of resources utilization where
reduction, reuse and recycling of materials prevails.
The Circular Economy model can be used in architecture, focusing on three
key resources of the sector that can work on a closed-loop: energy,
construction materials, and water [1].
Looking closely at green buildings shows the same objective targeted by
applying circular economy to building projects is achieved when green
building principles and practices are applied as well.
The end result of all these is, natural resources are preserved, cost is
drastically reduced, a larger percentage of waste instead of being sent to
landfills are reused and recycled, pollution and embodied energy are also
reduced, amongst several other benefits.
THE CIRCULAR ECONOMY MODEL
According to Ellen MacArthur Foundation, a circular economy is a systemic approach to
economic development designed to benefit businesses, society, and the environment. In
contrast to the ‘take-make-waste’ linear model, a circular economy is regenerative by
design and aims to gradually decouple growth from the consumption of finite resources.
The restorative and regenerative approach of circular economy is based on three key
principles which are;
Design out waste and pollution
Keep products and materials in use
Regenerate natural systems
The concept of Circular Economy has been gaining relevance and momentum since the
late 1970s, when researchers Walter Stahel and Genevieve Reday developed the vision
of an economy in loops and its impact on job creation, economic competitiveness, resource
savings, and waste prevention.
It is primarily focused on product, component and material reuse, remanufacturing,
refurbishment, repair, cascading and upgrading. It also emphasizes reducing energy
needs by driving and advocating alternative energy sources, like solar, wind, biomass
and waste-derived energy utilization throughout the product value chain.
Culled -concepts & practice of the circular economy by Anthanasios Valavanidis
Global environmental issues and the unsustainable use of natural resources has put high
pressure on earth’s life-support systems which in turn has led to the urgent need to apply
circular economy concepts to various facets of life, in a bid to ensure sustainability and
preservation of the eco system. Biodiversity loss, waste of freshwater resources, soil
desertification from excessive land use for food production, increasing air pollution in
urban areas, plastic pollution in the oceans, and dramatic climate changes are some of
the most serious environmental problems encountered and investigated to great length in
the last decades.
The model aids and promotes the resiliency of natural resources. It aims to replace the
traditional linear economy model of fast and cheap production and disposal with the
production of long-lasting goods that can stand the test of time, be repaired, or easily
dismantled and recycled. The current economic system is linear in nature, and its
approach is that resources are taken out of the ground, made into something, and later
discarded as waste. Only with a circular economy is sustainability possible. A model of
production based on a circular economy tends to extend the useful life of the product, but
also creates the opportunity for repair, refurbishment, and reuse of products before the
actual end of the useful life is reached.
The Circular Economy has already been put in place by many organizations and
businesses around the world. The sectors that have adopted the Circular Economy
approach are ones related to scarce or special materials or/and fragile supply chains,
according to Cerantola. "All the materials that are valuable for being recovered have
started to be circularized even decades ago; let's think about plastics, steel, gold or
aluminum.
There are lots of advantages to adopting the Circular Economy. First, the Circular Economy
commits to reducing water and energy consumption and using energy from renewable
sources. By reducing waste, it also diminishes the negative impacts associated with
overflowed landfills that contaminate water and soil. Not only does it have a positive
environmental impact, it is also good for enterprises and the economy.
WATER EFFICIENCY & NET ZERO WATER IN GREEN BUILDINGS
Seventy percent of the Earth’s surface is covered by water, but less than 3% of that water
is fresh water. Only 1% of that 3% is accessible and available for human use. According
to the United Nations Environment Program, if this trend persists, two out of every three
persons will live in water-stressed conditions by the year 2025. Also, recent U.S.
government survey showed at least 36 states expect to have local, regional, or statewide
water shortages by 2013. Each day roughly 340 billion gallons of fresh water are drawn
from rivers, streams, and reservoirs. Sixty-five percent of the water used up, is discharged
back into the water supplies after use. With the U.S. population doubling between 1950
and 2000, and its water demand tripling during the period, has created a huge gap that
needs to be resolved and effectively managed.
Circular Economy model can be used in architecture, focusing on three key resources, in
which water happens to be one of them. It aims to conserve water resources and ensuring
sustainability by reducing water consumption, minimizing water wastages, recycling
water, and maintaining a closed loop system approach. LEED also contributes to this
objective through its drive towards achieving water efficiency & net zero water in green
buildings.
Water Efficiency
Water efficiency helps to preserve and protect our aquifers and the supply of renewable
fresh water. The goal of the water efficiency is to reduce the quantity of water needed for
both internal and external water use by buildings which in turn brings about a reduction
in municipal water use, as well as the need for treatment of waste water. LEED actually
aims to conserve portable water usage through the water efficiency. Potable water comes
from wells or municipal water systems. Non-potable water is not suitable for human
consumption. Water conservation strategies are actually not more expensive than
traditional building methods. Buildings that use water efficiently can reduce operating
costs through lower water use and sewage fees. For those strategies where the cost may
be higher, the payback is usually very quick and fast.
Under water efficiency, LEED V4 considers outdoor and indoor water use reduction.
Outdoor water use reduction; LEED has the intent to reduce outdoor water consumption
for landscaping needs. It considers two approaches which includes the option of no
irrigation required, as well as the option of reduced irrigation.
No Irrigation Option;
This approach involves designing your landscape not to require a permanent irrigation
system. A temporary system is put in place for two years to enable the plants get fully
established. The end result of this, is that the water demand is reduced by a 100%.
To design a landscape that doesn’t require irrigation, you must utilize the practices of
Xeriscaping to design efficiency into the site from the very beginning. Xeriscaping is the
type of landscaping and gardening that reduces or eliminates the need for supplemental
irrigation. Eliminating irrigation is incredibly efficient and usually means land is taken
back to a historic context. Xeriscaping is based on seven common sense principles which
includes proper planning and design, soil analysis and improvement, appropriate plant
selection, practical turf areas, efficient irrigation, use of mulches, and appropriate
maintenance.
The primary driver for efficiency is choosing appropriate plant species for the climate the
building is in because those are the types of plants that will thrive under the local soil
conditions and weather patterns, and in doing that there is no better choice than using
native or adaptive plants
Native plants are those that grow naturally in an area or that have been in an area for
many years. Native plants require less water, fertilizer, and pest control. These plants can
be trees, shrubs, flowers, or grasses. Adaptive plants are non-native plants that perform
well in the local climate. Native and adaptive plants require less water and are more
disease resistant because they are suited to the region’s usual rainfall, soil, and
temperature. Project teams will need to choose plants that will perform best in the given
soil conditions and with the given amount of sun and shade in the area where the plants
will be located. Similar plants should be grouped together to maximize water efficiency.
Invasive plants should be avoided because they grow quickly and aggressively, spreading
and displacing other plants. Perennial flowers are preferred to annuals, because
perennials will come back year after year and will require less watering.
Other outdoor water reduction measures which play a major role in water conservation
efforts includes;
Drip Irrigation;
Drip irrigation minimizes water and fertilizer use because they allow water drip slowly to
the roots of plants, either onto the soil surface or directly onto the root zone, through a
network of valves, pipes, or tubing. Also, it is a type of micro-irrigation system i.e., lowpressure irrigation systems that spray, mist, sprinkle or drip water. The way it was
designed enables it to increase crop yields by delivering water more slowly to root
systems, and in so doing, achieve water conservation by reducing evaporation since water
can be applied directly to the plant roots. This system has an irrigation efficiency of 90%
as opposed to other conventional irrigation systems with about 65%.
Culled- https://www.landscapingnetwork.com/sprinklers-systems/drip-irrigation.html
Scheduling;
This is primarily centered on planning on when to water the landscape, maintain the
landscape and controlling outdoor pest from attacking the landscape. Deep watering for
an extended period of time is more favored than watering intermittently. Deep watering
forces the plant’s roots to push further down into the soil where more moisture can be
found over time. It is best to water the landscape during the coolest part of the day
especially in the morning, and avoid watering on windy days.
Weather Based Irrigation Controllers;
Weather- or sensor-based irrigation control technology uses local weather and landscape
conditions to align irrigation schedules to actual conditions on the site or historical weather
data. Instead of irrigating according to a preset schedule, advanced irrigation controllers
allow irrigation to match the water requirements and needs of plants. These new control
technologies offer significant potential to improve irrigation practices in homes. Weather-
based irrigation controllers can save nearly 24 billion gallons per year across the United
States—more than 7,000 hoses constantly running for a full year.
Water Audits;
This entails Performing at least an annual review of how much water is being provided to
different areas of the landscape in order to evaluate the needs of the area and to reduce
water use. This is because a landscape installed today will not have the same water
requirements that it will have three years from now, or even one year from now. Newly
installed plants need more water to become established. The fact is over time plants will
grow deeper roots and require less water.
Landscape Maintenance;
When talking about the health of a lawn, what comes to mind is mowing. The cutting of
grass week after week during the growing season is stressful to the grass. The best
approach is the hotter the weather, the higher the lawn should be cut. If turf grass is
included in the landscape design, raising the height of the mower blades will reduce the
amount of clippings and the need for watering. Longer grass protects the soil from being
scorched by the sun and prevents the germination of weeds. Leave the Clippings You
rarely see a commercial property bagging grass clippings because of the sheer quantity of
grass involved. However, many homeowners bag the clippings and then set them out for
garbage collection. Not only does this practice add waste to landfills, it is actually
detrimental to the grass. Forty percent of the nutrients that grass needs are lost when
clippings are taken away and not left to compost naturally.
Maintaining the Watering System can be carried out by checking sprinkler heads
periodically to prevent watering of streets and parking lots. Poorly installed sprinkler
heads and damage caused by landscaping maintenance can undermine the best of
intentions. Too many sprinklers shoot water into paved areas in the middle of a hot day.
Verify that sprinkler heads are pointed in the right direction to prevent valuable water
from being sprayed onto hardscapes and then evaporating.
Use Rainwater and/or Graywater;
Municipal water use for landscaping can be reduced if not eliminated by making the most
of alternative water sources. Both rainwater and graywater, though considered nonpotable, are excellent alternatives. Non-potable water is water that does not meet EPA’s
drinking water standards but can be used for onsite water reuse strategies.
Rainwater is normally collected in cisterns, barrels, or storage tanks. This approach is
called rainwater harvesting. For commercial applications a rooftop collection system can
be added. Rooftop rainwater collection systems have the added benefit of using gravity,
not a mechanical pump, to distribute the water. For residential applications a, simple
barrel can be installed next to a downspout.
Gray water on the other hand is water that can be used twice. Graywater is untreated
household waste water which has not come into contact with toilet waste. Graywater is
different from blackwater - untreated wastewater from toilets and urinals. Graywater
comprises 50-80% of residential wastewater. Like rainwater, graywater can be piped to
storage tanks for later use. Graywater can come from: bathtubs, showers, bathroom
sinks, washing machines and laundry tubs. Graywater does not include: potable water
(already treated water from municipal supplies or wells), waste water from kitchen sinks,
water from dishwashers, waste water from toilets and urinals (blackwater). If gray water
is filtered properly, reusing it for irrigation and further conveyance is safe from a health
perspective. But local codes must be checked before reusing graywater or rainwater.
Indoor Water Use Reduction;
For indoor water use reduction, LEED V4 has set a mandatory 20% reduction from
baseline water consumption as a prerequisite with further reduction required to earn a
credit up to a maximum of 50%.
This whole approach looks at restroom fixtures inside the building, water heating
appliances, as well as cooling towers and condensers. All newly installed toilets, urinals,
private lavatory faucets, and showerheads that are eligible for labeling must be WaterSense labeled or a local equivalent for projects outside the US. Water-Sense is a
partnership program sponsored by the U.S. Environmental Protection Agency that helps
consumers identify and choose water efficient products. Water-Sense labeled products
are verified to be high-performing, water-efficient fixtures and exceed the IPC standards.
For projects outside of the US, look for acceptable substitutes that have equivalent
performance.
The prescriptive path and usage-based calculations are normally used to ensure
compliance to reduction levels. The prescriptive path of using water sense labeled
products can only meet the requirements for prerequisite of 20% reduction, but a usagebased calculation method would have to be carried out to ensure further reduction to 50%.
Typical fixtures used include ultra-low flow shower heads, ultra-low flow faucet aerators,
dual flush toilets and flushometer, waterless urinals. Also, alternative water sources like
rain, grey water can be used to achieve further reduction beyond 20%.
Other indoor water reduction strategies aside use of efficient fixtures includes;
Rainwater harvesting system;
Culled- https://www.researchgate.net/figure/Schematic-of-a-rainwater-harvestingsystem_fig8_259923841
Rainwater harvesting helps to conserve potable water sources and also a suitable solution
for decreasing the high sewage level, mitigating floods, and soil erosions.
It is actually designed to aid potable water reduction by collecting and accumulating the
rainwater via tubes in tanks and other suitable medium, which can then be used for
different purpose that require low-quality water as irrigation, toilet flushing etc. After
proper treatment and disinfection, it can also be used as potable water. A rainwater
harvesting system generally is composed of a collection (catchment) area, a conveyance
system consisting of pipes and gutters, a storage facility, a delivery system consisting of
a tap or pump, and a disinfection system which is actually optional.
Greywater recycling;
Greywater is wastewater generated from wash hand basins, showers, and baths, which
can be recycled on-site and then used for WC flushing, landscape irrigation, and other
non-potable uses. Greywater does not include wastewater discharge from laundry,
dishwashers and kitchen sink due to the high nutrient levels. Bathroom’s discharges are
classified as wastewater with fecal contamination. The amount and quality of greywater
will in part determine how it can be reused. Irrigation and toilet flushing are two common
uses. Greywater is suitable for irrigating lawns, trees, ornamentals, and food crops. Care
must be taken to ensure grey water usage complies with local code and standards.
Net Zero Water
Culled - https://www.energy.gov/eere/femp/net-zero-water-building-strategies
A net zero water approach in buildings is designed to minimize total water consumption,
maximize alternative water sources, minimize wastewater discharge from the building
and return water to the original water source
This actually creates a water-neutral building where the amount of alternative water used
and water returned to the original water source is equal to the building's total water
consumption.
The goal of net zero water is to preserve the quantity and quality of natural water
resources with minimal deterioration, depletion by utilizing potential alternative water
sources and water efficiency measures to minimize the use of supplied freshwater.
Ultimately, a net zero water building (or campus) completely offsets water use with
alternative water plus water returned to the original water source.
However, if the building is not located within the watershed or aquifer of the original water
source, then returning water to the original water source will be unlikely. In those cases,
a net zero water strategy would depend on alternative water use.
To obtain LEED Zero Water certification, a project must achieve a potable water use
balance of zero for the past year.
Water Balance = Total Potable Water Consumed – (Total Alternative Water Used + Water
Returned to Original Source)
Water returned to its original source includes rainwater stored and infiltrated through
green infrastructure, and wastewater treated and returned to the local watershed or
aquifer through decentralized wastewater treatment systems. Calculations for the amount
of rainwater retained and infiltrated on-site must be based on the calculation methodology
outlined under LEED v4 Sustainable Sites credit Rainwater Management.
RENEWABLE ENERGY USE & NET ZERO ENERGY IN GREEN
BUILDINGS
Renewable Energy Use;
Circular Economy commits to reducing energy consumption and using energy from
renewable sources. It does this by advocating alternative energy sources, such as solar,
wind, biomass and waste-derived energy utilization throughout the product value chain.
LEED V4 on the other hand, encourages the use of renewable energy in buildings by
awarding credit points to projects that have a certain percentage of their energy from
renewable sources. Its sole intent is to reduce the environmental and economic harms
associated with fossil fuel energy by increasing self-supply of renewable energy. Onsite
renewable energy systems offset building energy costs and reduce GHG emissions.
The renewable energy produced is expressed as a percent of the annual energy cost. For
projects that failed to carry out an energy model, the Commercial Building Energy
Consumption Survey (CBECS) database can be used to estimate the annual energy use
and cost.
When considering eligible systems, it is important to note that some biofuels which have
high GHG potential or toxicity potential cannot be included, and they include burning
trash, forest biomass other than mill residue, wood covered with paints and coatings,
preserved wood, such as pressure-treated lumber.
Eligible on-site systems used for LEED projects include Photovoltaic systems, wind energy
systems, solar thermal systems, biofuel-based electrical systems, geothermal heating
systems, geothermal electric systems, low-impact hydroelectric systems, wave and tidal
power systems. It is usually best and most advisable for the system to be oversized, so
as to create a safety net that can allow for becoming a potential power supplier to your
local energy provider. This is called net metering, and creates a situation that allows the
system to become a small profit center.
Photovoltaic Systems;
Culled- https://www.canstockphoto.com/images-photos/photovoltaic-system.html
A photovoltaic system, also called a PV system or solar power system, is a power system
designed to supply usable solar power by means of photovoltaic panels. It consists of an
arrangement of several components, including solar panels to absorb and convert sunlight
into electricity, a solar inverter to convert the output from direct to alternating current, as
well as mounting, cabling, and other electrical accessories to set up a working system.
Wind Energy Systems; Wind energy systems involves the use of wind to provide
mechanical power through wind turbines which turns electric generators for electrical
power. Wind power is a popular sustainable, renewable source of power that has a much
smaller impact on the environment compared to burning fossil fuels.
Culled - https://www.shutterstock.com/image-photo/wind-turbines-on-beautiful-sunnysummer-1189160377
Solar Thermal Systems; Solar thermal energy is a system that harnesses solar energy to
generate thermal energy for use in industry, residential and commercial sectors.
Biofuel Based Electrical Systems;
Culled- https://www.mpoweruk.com/biofuels.htm
Biofuels are classified broadly into first- and second-generation biofuels.
First-generation biofuels are made from food sources grown on arable land, such as
sugarcane and corn. Sugars present in this biomass are fermented to produce bioethanol,
an alcohol fuel which serve as an additive to gasoline, or in a fuel cell to produce electricity.
Second-generation biofuels utilize non-food-based biomass sources such as perennial
energy crops and agricultural residues/waste. The feedstock used to make the fuels either
grow on arable land but are byproducts of the main crop, or they are grown on marginal
land. Waste from industry, agriculture, forestry and households can also be used for
second-generation biofuels.
Culled from - https://en.wikipedia.org/wiki/Bioenergy
Geothermal Heating Systems; A geothermal heat pump (GHP) or ground source heat pump
(GSHP) is a central heating and/or cooling system that transfers heat to or from the
ground, often through a vapor-compression refrigeration cycle. It uses the earth all the
time, without any intermittency, as a heat source (in the winter) or a heat sink (in the
summer). This design makes the most of the moderate temperatures in the ground to boost
efficiency and reduce the operational costs of heating and cooling systems, and may be
combined with solar heating to form a geo-solar system with even greater efficiency. They
are also called geo-exchange, earth-coupled, earth energy systems.
Low Impact Hydro Electric Systems; Hydroelectric power uses the force of flowing water
to create renewable energy. The flow through rivers turns turbines that produce electricity.
Culled - http://www.greenpoweremc.com/content/low-impact-hydroenergy#:~:text=Hydroelectric%20power%20is%20attractive%20because,Few%20viable%20sit
es%20remain.
Wave & Tidal Power Systems; Tidal power or tidal energy is harnessed by converting
energy from tides into useful forms of power, mainly electricity using various methods.
Although not commonly used, tidal energy has the potential for future electricity
generation. It is far easier to predict tides than the wind and sun.
Net Zero Energy;
LEED is actually promoting net zero energy through its LEED Zero Energy certification.
According to the US Department of Energy (DoE), a zero-energy building is defined as the
building that produces enough renewable energy to meet its own annual energy
consumption needs and requirements.
There are several metrics that define the performance of buildings such as the net-zero
site energy building, net-zero source energy buildings, net-zero energy cost building, and
net-zero energy emission building.
The net-zero site energy building is defined as the building that produces as much energy
that is equal to what is consumed when measured at the site. The net-zero source energy
building is the building that produces as much energy on an annual basis as it uses as
compared to the energy content at the source. On the other hand, the net-zero energy cost
building is the building that uses energy efficiency and renewable energy strategies as
part of the business model.
For a project to obtain LEED Zero Energy certification, it must achieve a source energy use
balance of zero for the past year as a way of meeting the certification requirements. The
net zero energy balance is based on the quantity of source energy delivered and the
quantity of renewable energy that displaces non-renewable energy on the grid.
Renewable energy generated and used on site reduces the amount of energy delivered.
Source Energy Balance = (Total Source Energy Delivered) – (Total Non-Renewable Source
Energy Displaced).
Culled - https://www.buildinggreen.com/newsbrief/world-s-first-leed-zero-building
The building was converted to a two-story warehouse, roughly 4,700 ft2, originally built in the 1980s. A 15kW
rooftop solar array provides 25% more energy than is needed to operate the 25-person office space.
MINIMIZING & ACHIEVEING NET ZERO WASTE IN GREEN
BUILDINGS
Circular Economy, is a system of resources utilization where reduction, reuse and
recycling of materials prevails, and in the end results in drastic waste reduction.
Minimizing Construction Waste
LEED V4 as part of managing construction waste makes it mandatory for projects to have
a specified location for storage and collection of recyclables. The intent is to reduce the
waste that is generated and hauled to and disposed of in landfills. In addition, there is
also a requirement for the safe collection, storage, and disposal of two out of the following
hazardous waste sources: batteries, mercury-containing lamps, and electronic waste, and
also, finally the development of a construction and demolition waste management plan.
LEED V4 rewards projects with credit points for diverting 50% of waste generated from
three waste streams, 75% of waste generated from four waste streams, or the option of
not generating more than 2.5 pounds of construction waste per square foot of the floor
area.
Other waste reduction strategies include;
Source Reduction;
Eliminating waste at the source, also known as source reduction, saves cost and valuable
landfill space. It entails considering waste generation during the design phase, employing
conservative purchasing practices, and by reusing excess materials at the jobsite. Before
construction begins, a construction waste management plan should be developed that
identifies potential waste streams and where waste diversion can be put in place—
salvage this waste, reuse it, and recycle it. If the waste can be taken out of the building
and reused elsewhere, it avoids waste disposal in landfills and incinerators. Be sure the
plan is actually put into practice and that the team tracks the waste through reports from
the waste haulers to check that the waste management plan is actually working. Typical
approaches include
Working with suppliers to streamline purchasing, requesting materials come with minimal
or no packaging, purchasing previously used or salvaged item, determine where existing
policies and procedures might represent a barrier to purchasing used or recycled
materials, keeping a binder of information on product specifications and prices and check
back with manufacturers regularly for updates, asking suppliers to take back or buy back
damaged or unused materials and packaging, streamlining supply estimations by making
sure orders do not exceed your requirements etc.
Material Reuse;
Reuse includes salvaged, refurbished, or reused products. LEED V4 favors reuse of
existing building materials found onsite or salvage building materials from off-site. Typical
reused materials on LEED projects include structural elements like floors and roof decking,
enclosure materials, and permanently installed interior elements like walls, doors, floor
coverings, ceiling systems. Windows and other hazardous materials are mandatory
excluded from the list of items that can be reused. The minimum percent of reused
materials in terms of surface area is 25%, with increasing increments of 50% and 75%.
Points vary between BD&C projects and Core and Shell projects. Also, for LEED V4,
Products meeting materials reuse criteria are valued at 100% of their cost for the purposes
of credit achievement calculation. Projects can reuse both fixed and finish materials for
this credit. Reusing materials reduces waste generated & the amount of materials
deposited in landfills.
Recycling Waste Materials;
Recyclable materials, components and assemblies particularly post-consumer recycled
content plays a significant role in ensuring limited and depleting resources are conserved,
while also ensuring that waste is diverted from landfill. Extended producer responsibility,
closed-loop recycling, and ‘take back’ programs are gaining wide acceptance in the
industry. Most carpet manufacturing companies in the US practice the take back program.
Also, Steel, glass, and metals are highly durable and they can be recycled again and
again. LEED V4 encourages recycling of materials by ensuring products meeting recycled
content criteria are valued at 100% of their cost for the purposes of credit achievement
calculation, while extended producer responsibility is as well valued at 50% of the cost.
For LEED V4 Recycled content must meet the definition set by ISO 14021-1999 for
environmental labels and declarations. Recycled content is the sum of postconsumer
recycled content plus one-half the pre-consumer recycled content, based on cost.
Every ton of C&D recycled result in a corresponding reduction of waste sent to landfills.
In addition to less land areas needed for landfilling; environmental issues associated with
C&D disposal is drastically reduced. For example, one problem frequently encountered
with C&D debris landfills is the generation and release of hydrogen sulfide, a foulsmelling gas which poses a risk to human health. Recycling scrap, agricultural products
and other waste helps to prevent the formation of this noxious gas. Also, along with less
land area needed and environmental benefits, the long-term costs associated with
owning, operating and maintaining these landfills in the future becomes reduced.
Culled- https://tr.pinterest.com/pin/539235755362788176/
Waste-to-Energy;
Waste-to-energy might be an option if reuse or recycling is not feasible. Waste-to-energy
focuses on the potential to improve the sustainable management of waste, by using waste
as a medium to produce energy.
Culled - https://theaseanpost.com/article/turning-waste-energy-philippines
Net Zero Waste
Zero waste management means the holistic concept of waste management which
recognizes waste as a resource produced during the conceptual phase of the process of
resource consumption. The management of zero waste is therefore a sustainable approach
of avoiding and management of waste and resources. Zero waste is therefore concerned
with waste prevention through sustainable design and consumption practices, optimal
waste recovery and not waste management by landfill or incineration. It supports waste
prevention and avoidance rather than waste treatment and disposal strongly.
To obtain LEED Zero Waste certification, a project must achieve GBCI’s TRUE Zero Waste
certification at the Platinum level. The TRUE Zero Waste program requires projects to have
a zero-waste policy in place, achieve an average of 90% or greater overall diversion from
landfill, incineration (waste-to-energy) and the environment for solid, non-hazardous
wastes for the most recent 12 months, and fulfill five other minimum program
requirements. A project team submits their TRUE Zero Waste Platinum certification for
GBCI review in order to earn LEED Waste Certification.
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s
13. https://www.ellenmacarthurfoundation.org/explore/the-circular-economy-in-detail
14. https://www.theguardian.com/sustainable-business/2015/mar/05/water-circulareconomy-revolution
15. LEED V4 Rating System
16. LEED BD+C study guide by GBES