Sustainability | Renewable Energy

Green building best practices

Elements of modern green building

Homeowners and businesses of every size the world over are investing in efficient green building techniques, measures, and strategies; for the sake of the environment, and the comfort, well-being (and wallets) of the building's occupants. 

Elements of modern green building include:

  • LEED technologies and best practices in developing a property,
  • energy-efficient use of construction materials and building resources,
  • use of low-carbon steel and concrete,
  • replacing gas-fired boilers with electric (and renewable) HVAC systems, heat pumps, etc...,
  • energy-efficient appliances and windows, and water-saving appliances (such as Energy Star products), 
  • quality insulation,
  • cool roofs,
  • rainwater collection systems,
  • solar PV on the property,
  • (as well as other green building solutions discussed below).

Global Green Building

In its World Energy Outlook, the International Energy Agency identifies pathways for clean energy technological solutions needed to reach global carbon neutrality (i.e. net zero GHG emissions) by 2050. It also details interim goals that will ensure the world is on the path to carbon neutrality. By 2030, in the developed, industrial world, 1/2 of all buildings need to be retrofitted to create energy-efficient buildings that rely on clean energy and electricity for core functions. In the developing world, that number drops to 1/3 of all buildings need to be retrofitted with energy efficiency upgrades by 2030.

In order to achieve these efficiency goals, the majority of buildings in cities worldwide must be retrofitted with the latest efficiency technologies. The most straightforward path to achieving these building efficiency goals is the electrification of buildings; and additionally, weatherization of buildings is an optimal solution.

Green Building Solutions

Electrification of buildings includes replacing gas furnaces, gas boilers, and conventional HVAC systems fueled by natural gas or heating oil. Conventional HVAC systems should be replaced with electric (or renewable) heat pumps and all-electric (or renewable) HVAC units. Building electrification also involves ensuring all other major building appliances are replaced with electric or renewable versions, such as electric water heaters or solar water heaters (among other efficient building appliances, discussed below).

Renewable solutions for buildings include solar panels, solar water heaters, and geothermal heat pumps. Additionally, there is the promising, still in development, hopeful future technology of hydrogen-fueled boilers, and other hydrogen solutions for buildings.

Optimal building weatherization solutions include adding cutting-edge efficient insulation to buildings (discussed below); as well as double or triple pane windows, and/ or various efficient high-tech smart windows (also discussed below). Weatherization of buildings involves hardening the exterior of buildings to weather, as well.

In order for buildings to meet current sustainability standards, new buildings should ideally implement the energy efficiency technologies listed above, and all existing buildings should be retrofitted to include these green building efficiency solutions. Retrofitting existing buildings to meet current energy efficiency standards is one of the most effective measures that can be taken to act on climate globally.

LEED (Leadership in Energy and Environmental Design)

In order to be LEED-certified, a building must maximize energy efficiency, following these basic guidelines for LEED buildings:LEED

The five critical areas of focus, as laid out by the USGBC, are sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality.

Sustainable site development involves, whenever possible, the reuse of existing buildings and the preservation of the surrounding environment. The incorporation of earth shelters, roof gardens, and extensive planting throughout and around buildings are encouraged.

Water is conserved by a variety of means including the cleaning and recycling of gray (previously used) water and the installation of building-by-building catchments for rainwater. Water usage and supplies are monitored.

Energy efficiency can be increased in a variety of ways, for example, by orienting buildings to take full advantage of seasonal changes in the sun’s position and by the use of diversified and regionally appropriate energy sources, which may—depending on geographic location—include solar, wind, geothermal, biomass, water, or natural gas.”   [click link for more]   FROM-

Sustainable building materials

Builders are increasingly turning to advanced framing techniques to help reduce their overall building costs; and to significantly lower their carbon footprint. Advanced construction has the same overall structural stability and integrity as most standard construction techniques. However, with advanced framing techniques, up to a third less lumber is used, and framings are quicker to assemble. The savings are then put toward the incorporation of greater insulation (and other green building strategies), which can lead to overall energy savings, at no extra cost to the builder or homeowner.

Many warehouses and retail outlets worldwide are now stocking 50-100% reclaimed materials for new-builds and home repairs. Recycled and reclaimed materials are commonly used in advanced green buildings. These materials for green building with advanced green construction include wood, lumber, bamboo, recycled plastic, recycled glass, and composite materials such as epoxy. Not only does the use of reclaimed materials and building supplies prevent the unnecessary use of natural resources; but the products are cheaper across the board (while still maintaining top quality).

Another increasingly common feature used to create today’s green building is low maintenance materials for exteriors and outdoor features. For example, the use of fiber-cement siding immediately rules out the chance of rot, while at the same time greatly reducing the frequency of painting/ touching-up. Likewise, the use of composite materials for decking and other outdoor features reduces the need for occasional resealing and varnishing – excellent for the pocket and the environment.

Below, at the end of this article, are guides and examples of passive building construction- the most cutting-edge energy efficiency techniques in building sustainably.

Energy and water-efficient appliances/ building fixtures

These efficiency appliances are commonly used in sustainable properties:

Flooring using composite materials, cold weather epoxy, and/ or radiant heating, can also significantly contribute to building efficiency, and energy savings. Another super-efficient upgrade in modern green buildings are solar water heaters. Optimal energy-efficient home and building appliances are wi-fi enabled smart appliances linked in with home energy management (HEM) systems. For more on HEM systems, please see: Improving Energy Efficiency - Green Building

In order for any existing building to transition to become a green building, conventional low-efficiency fixtures and appliances should be swapped out for sustainable versions. It might be necessary to begin to retrofit the building in order to incorporate the above-mentioned energy-efficient appliances and fixtures.

New construction in the state of California is required to be entirely net-zero energy homes (currently for most new residential construction in the state, expanding to include all new commercial buildings by 2030); as explained in the following article:  The Cottle Zero Energy Home; CA's Zero Net Energy Mandate

PLEASE ALSO SEE>>> Improving energy efficiency - Green Building

Solar PV and solar water heaters
solar water heater

It is helpful for a green building to have its own self-reliant source of energy. Today, solar photovoltaics (PV) and solar thermal technologies (such as solar water heaters) can do the job excellently. Recently, there have been dramatic breakthroughs in solar energy technologies that will help further the mainstream use of solar technology, bringing the cost of solar down, and the efficiency of solar up. Below in this article are shining examples of solar rooftop PV for buildings; one is Vauban, Germany's solar settlement, and another for the Bullitt Center in Seattle.

Heat pumps

There are two types of heat pumps- air-source electric heat pumps and geothermal heat pumps. Of the two of them, the geothermal type is a renewable energy source. Geothermal heat pumps are piping systems placed below the ground that transfer heat energy from underground outside of a building to augment/ replace HVAC and water heaters inside the building; and acts as a central heating and/ or cooling system.

Geothermal heat pumps use the earth's natural energy, thus a source of renewable energy, the heat energy underground which is piped in for use with a building's HVAC system and water heaters. This significantly reduces energy bills, as well as saving energy. The use of geothermal heat pumps has routinely cut heating bills in half while operating with more than double the efficiency of traditional HVAC systems.

Currently, a more popular option than geothermal heat pumps, a clean energy source of heating and cooling for your property which is also energy and cost efficient, are electric air source heat pumps. Electric heat pumps are super energy efficient; and may or may not be powered by renewable energy; depending on the energy sources for the municipal grid where the building is located (or the property itself may be powered by solar panels or another renewable energy source). Globally, electric heat pumps are projected to be installed in over 20% of new buildings by 2030. Electric heat pump water heaters are also rapidly gaining popularity throughout the world.

Rainwater collection systems

Image result for rainwater collection systemsBecoming the standard of new buildings across the country, rainwater collection systems can be built into properties in order to provide free and reliable irrigation to the owner’s garden and for many uses in the household or building. Rainwater collection systems capture and filter rainwater to store and eventually use in the building which collected the water. Rainwater collection systems can be simple or complex, but either way, they are a great way to save on your water bill and conserve water over the long term.

As rainwater collection systems grow in popularity, the necessary collection tanks, filtration units, and water storage and delivery systems are becoming increasingly available in hardware stores and online. While usually non-drinkable, the collected, filtered, and stored potable water can safely be used for almost any other household purpose. Implementation of a rainwater collection system results in increased water supply for the given property, reduction in water bills, reduction in use from the municipal water supply, and the reduction of stormwater runoff.

Energy-efficient windows

The efficiency of buildings is influenced by the size, quality, and effectiveness of keeping in heating and air conditioning, of windows installed. Dual-pane windows, and triple-pane windows, increase building HVAC efficiency and reduce energy consumption for HVAC systems. In addition, it is possible to reduce lighting and heating demands exponentially by the use of cutting-edge smart glass technology with newly installed or retrofitted high-tech windows.

Using electrochromic smart glass for windows enables you to determine the amount of light you may want to block. Other types of smart window glass include photochromic and thermochromic (responding to light or heat, respectively), which adjust the tint of the glass from opaque to dark in response to varying degrees of sunlight, thus blocking sunlight and cooling interior space. The heat from sunlight is regulated by electrochromic smart glass, reducing dependence on HVAC to heat or cool rooms. Building developers using this glass for use as windows indicate that the glass can reduce HVAC costs by over 25%.

Cool RoofCool roofs

Cool roofs and green roofs lower surface temperatures on roofs in bright sunlight compared to a conventional roof. This is usually done with greenery, white vinyl,  or a solar reflective coating. Finishing with a cool roof is a highly recommended strategy since, for example, during summer, air conditioning requirements will decrease; leading to reduced energy costs. A cool roof reflects and absorbs solar radiation better than standard roofs.

Efficient insulation

Most people can actually attribute their high energy bills to poor insulation. Insulation technology, both with new and recycled material, has improved dramatically recently. Modern insulation has come a very long way since insulation materials used cancer-causing asbestos (which causes mesothelioma). While insulation with new materials, especially state-of-the-art insulation, still represents a higher efficiency, some insulation materials today are recycled products that are cheap, readily available, and still represent the latest in insulation technology. Cellulose (mostly from shredded newspaper), recycled denim, and even some plant and waste materials are now used for insulation, in addition to fiberglass, polyurethane, and other materials. Having a properly insulated building will reduce energy costs.

Please read: - (the following quote is from this article:) "...many buildings would benefit the most from such steps as adding insulation, sealing leaky windows and doors, and replacing older single-pane windows with newer double-pane versions..."

Vauban, Germany's solar settlement; passive building

homes in Vauban, Germany

A community of homes and buildings that represent the most energy-efficient group of properties in the world- Vauban, Germany, an ultra-sustainable city district in Freiburg, represents the cutting-edge of sustainability in terms of green building. New homes and buildings built with maximizing sustainability in mind to create the absolutely greenest, most efficient, most sustainable properties, are plus-energy homes and buildings (like those in Vauban, Germany, that produce more energy than they use).

Most homes in the solar settlement of Vauban, Germany get energy for their own home and for the municipality of Vauban from rooftop solar panels (and from energy generated from biomass in a local combined heat and power plant). Another European city that employs passive home building standards for all commercial building and construction of residential homes in the city is Vaxjo, Sweden. The ideal buildings in terms of energy efficiency and sustainability are passive design, zero net energy buildings. The ideal sustainable home/ building generates its own energy, either via solar panels on the property, community solar, a geothermal heat pump, and/ or works off of a clean energy micro-grid.

Here's an article about the Solar Settlement in Vauban, Germany from Smart Cities Dive-

"Public energy and heat are generated by a highly efficient woodchip-powered combined heat and power generator connected to a district heating grid. 42 building units [in the Solar Settlement] are of the Passivhaus [passive building design] standard...houses adhere to a "plus-energy" standard, producing more energy than they use, with surpluses sold back to the city grid and profits split between each household."     FROM  -

Here's detailed information and a simple diagram on passive building. Passive building design principles include buildings that-

* Employ continuous insulation throughout [the building's] entire envelope without any thermal bridging.

  • The building envelope is extremely airtight, preventing infiltration of outside air and loss of conditioned air.
  • Employ high-performance windows (double or triple-paned windows depending on climate and building type) and doors - solar gain is managed to exploit the sun's energy for heating purposes in the heating season and to minimize overheating during the cooling season.
  • Uses some form of balanced heat- and moisture-recovery ventilation.
  • Uses a minimal space conditioning system.      FROM -

Please see these articles on two of the cities that are featured in this article for employing passive building standards when constructing all commercial buildings and residences in the city:

Vauban, Germany - The Greenest City in Europe


Fossil-free Vaxjo - Passivehouse construction standards

Please see the following articles on the latest green building and related energy efficiency technologies:

LEDs, CFLs: Lighting For a Brighter Future

Energy Star - an international standard

Home Energy Management (HEM)

Demand response: improving energy efficiency

Renewable energy storage

Smart grid overview

Smart meters - a more efficient use of utilities

Please click & read:

The Bullitt Center Seattle: The World’s Greenest Building


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