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Urban Agriculture And Sustainability Goals

November 12, 2019 By EarthWise Leave a Comment

In 2016, the City Council of Phoenix, Arizona adopted eight Environmental Sustainability goals for 2050 that lay out the desired long term requirements in order to become a Sustainable Desert City. Recently, a group of researchers from Arizona State University assessed how urban agriculture can help Phoenix, a desert city of 1.6 million people, meet those sustainability goals.

Using public records and high-resolution satellite imagery, researchers analyzed the potential benefits of growing crops in three types of urban areas in Phoenix: vacant lots, rooftops, and building facades. The study, which was supported by the National Science Foundation and the USDA, estimated that there are 28 square miles (or 5.4% of city space) available for urban agriculture. The data-driven analysis found that 71% of the available areas for urban agriculture would come from existing buildings as opposed to vacant lots.

All this available space for urban agriculture in Phoenix could supply the city with nearly 183,000 tons of fresh produce annually, which would allow for the delivery of fresh fruits and vegetables to all of the city’s existing food deserts. In fact, the city’s own urban-agriculture output could meet 90% of the fresh produce demand that currently exists in Phoenix.

In addition to producing food, rooftop agriculture could also reduce the energy use in buildings by 3% per building per year, and displace more than 55,000 tons of CO2 annually. The use of vacant lots could increase the total Phoenix green space by 17%, and reduce the number of areas lacking green space by 60%.

This study demonstrates the many different ways that urban agriculture can benefit a city.

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Urban agriculture can push the sustainability

Photo, posted May 10, 2011, courtesy of Stephen Zank via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Two Million Solar Installations

July 1, 2019 By EarthWise Leave a Comment

Three years ago, we reported that the United States had installed its one millionth solar energy system, a feat that took 40 years to accomplish. Recently, the Solar Energy Industries Association announced that there are now more than 2 million U.S. installations.

Analysts forecast that there will be 3 million installation in 2021 and 4 million in 2023.

California continues to lead the nation in installing solar power. More than 50% of the first million installations were in that state and California accounted for 43% of the second million. Its share is nevertheless slowly dropping with the growth of the residential solar sector that is rapidly diversifying across state markets. Some places have seen extremely rapid growth. In South Carolina, there were barely more than 1,000 cumulative installations in 2016; today, the state is home to more than 18,000 solar systems and expects to add 22,000 more over the next five years.

The five leading states in terms of number of solar installations are California, Arizona, New York, New Jersey, and Massachusetts. Other states recently seeing rapid growth in solar installations are Texas, Utah, Florida, Rhode Island and Maryland. Looking ahead, Illinois is forecast to grow from only 4,000 installations today to nearly 100,000 by 2024. The top ten state markets apart from California expect to add nearly 750,000 installation over the next five years.

The United States is at least the third nation that is home to more than 2 million solar installations. (Australia hit the milestone late least year and Japan actually topped 2 million in September 2014).

According to forecasts from analyst first Wood Mackenzie, by the year 2024, there will be on average one new solar installation every minute.

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The United States surpasses 2 million solar installations

Photo, posted January 11, 2012, courtesy of the Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Trouble On The Colorado

April 4, 2019 By EarthWise Leave a Comment

The 1450-mile-long Colorado River begins in the Rocky Mountains and wends its way to the Gulf of California, creating the Grand Canyon along the way, and providing water to some 40 million people. The amount of Colorado River water promised to users is far more than actually flows between its banks, and that amount is dropping.

An unrelenting drought since 2000 has resulted in the water levels of the two largest reservoirs of Colorado River water – Lake Mead and Lake Powell – being at all-time lows.

Lake Mead, just outside of Las Vegas, is the reservoir of Hoover Dam, which provides power for millions of people in Southern California, Nevada, and Arizona. The last time Lake Mead was full was in 1983. It has slowly declined and now is 40% full.

If the lake level drops another 7 feet to 1075 feet above sea level, it will trigger a Tier 1 declaration, mandating cuts to water allocations to Arizona and other states. If the level drops to 1050 feet, it would reach Tier 2 at which point Hoover Dam would have to stop generating electricity because water levels would be too low to flow through it. If the lake level drops all the way to 895 feet, it would be below the level at which water can be piped out of it. This is known as the “dead pool”.

These scenarios are no longer doomsday fantasies. Water managers in the Southwest see the writing on the wall and are busy making contingency plans and developing ways to use less water from the Colorado River. The booming city of Phoenix in particular is hard at work finding alternative ways to provide water for its millions of citizens. On the Colorado, drought in the new normal.

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