Energy-efficient buildings use and generate cleaner energy. They are comfortable to live in, affordable, healthy, and more environmentally friendly. Having an energy-efficient home is becoming more and more important, as the high demand for energy is unsustainable.

Energy-efficient homes produce less greenhouse gas emissions and will reduce pollution and the negative health side effects of this pollution. However, energy-efficient buildings require an initial investment, as they can be more expensive to build, but expenses are usually recouped in the first few years of living there due to reduced energy expenses. This practice is effective in its environmental impact if the people who live in the homes also develop sustainable, energy-efficient daily routines.

For instance, 600 Mosques in Morocco, Africa are currently being converted into green, energy-efficient buildings as a part of their sustainability goals.

Over the years, changes to technology have given rise to many alternative sources of energy that can be harvested through modern techniques.

Renewable resources include renewable energy sources like wind, solar, geothermal, hydropower, wave, and tidal power. Renewable resources have a positive environmental impact. They are clean energy sources and are widely available and naturally replenished. However, renewable resources, such as energy, can be quite expensive. They also sometimes have a negative impact — for example, wind energy can result in the death or serious injury of birds.

Cities around the world are using different renewable resources. More advanced technologies, such as geothermal energy, are being used in Iceland, El Salvador, New Zealand, Kenya and the Philippines. Wind turbines are used worldwide, but predominantly in China, the United States, and Germany.

In Canada, the First Nations community, the Haida Nation, is converting their traditional land’s energy source to wind turbines as a cleaner source of energy. The Navajo Nation in the United States is also making this conversion on Indigenous lands. As the world continues to turn to these sources of energy, the positive environmental impact will continue to grow.

Cleaner transportation practices can help reduce the carbon emissions in the atmosphere. Public transportation is a fast, affordable, and reliable sustainability project. It provides an alternative option to driving the car, which reduces congestion, alleviates stress, improves health, and reduces air pollution.

However, some people have difficulty accessing public transportation based on their location, and it does not always work with everyone’s schedules. The majority of cities around the world uses public transportation. In Bristol, United Kingdom, buses are powered by food waste, called bio-methane gas, which also reduces greenhouse gas emissions.

Another consideration is using transportation that relies on human or animal power, like bicycles, rickshaws, canoes, kayaks, scooters, skateboards, dogsleds, reindeer sleds, horses, donkeys, camels, etc. They are environmentally friendly, and result in a positive health benefit. One setback is the restrictions of speed and distance.

Roof gardens are rooftops that are covered with earth so that plants can grow on them. They are built in layers to allow drainage and prevent harm to the building’s roof.

Roof gardens have several advantages; they regulate temperatures keeping houses cool in the summer and warm in the winter, they can serve as urban vegetable gardens, they improve air quality in cities, and they absorb 80% of the rain and therefore avoid potential floods. They also efficiently reduce carbon dioxide emissions and improve air quality.

However, green roofs can be expensive to design, they are an additional weight load on the building, and they require regular maintenance. More countries around the world are adopting green roofs in urban areas, including Canada, Egypt, Brazil, Germany, Japan, Singapore, and Hong Kong.

Creative waste and recycling initiatives play a critical role in helping cities improve their energy efficiency and become more sustainable.

When items are reused, it saves the amount of energy and natural resources that would be required to create new items. Waste can also be converted into energy. This is called biomass food waste.

As a renewable energy source, food waste will always be abundant. There has also been research conducted into ways to convert food waste into energy cleanly with plants.

These initiatives can be found around the world, but most notably in Singapore and Songdo, South Korea, which use advanced facilities to break down more waste into energy. Areas of the United Kingdom, the United States, and China are also leaders in this initiative.