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Potential for floating solar

July 16, 2024 By EarthWise Leave a Comment

As installations of utility-scale solar power continue to expand around the world, there is the issue of where to put them. They do take up considerable amounts of space and, in many places, available land is at a premium.

An alternative to taking up available land with solar panels is to deploy them on the surfaces of lakes and reservoirs. A study by researchers at Bangor and Lancaster Universities in the UK calculated the potential electrical output for floating photovoltaic installation on nearly 68,000 lakes and reservoirs around the world. The lakes and reservoirs selected were no more than 6 miles from a population center, were not in a protected area, and didn’t dry up and didn’t freeze for more than six months each year. The calculations were based on covering just 10% of the surface area of the bodies of water.

The calculations were evaluated country-by-country. Five countries could meet their entire electricity needs by floating installations including Papua New Guinea, Ethiopia, and Rwanda. Many countries, mostly in Africa, South America, and Central Asia, could get between 40% and 70% of their electricity this way. Most European countries could only meet a few percent of their electricity needs from floating solar, but even that could be significant.

There are other benefits to floating solar apart from freeing up land. The panels stay cooler, making them more efficient, and reservoirs lose less water through evaporation and the growth of algal blooms is reduced because there is less light reaching the water.

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Some countries could meet their total electricity needs from floating solar panels, research shows

Photo, posted November 25, 2015, courtesy of Smabs Sputzer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The World’s Largest Tidal Device | Earth Wise

June 18, 2021 By EarthWise Leave a Comment

Most of the world’s activity in renewable energy is focused on solar and wind power. The use of both is expanding rapidly. But there is also marine energy to be exploited. Ocean waves and tidal movements hold huge amounts of energy. Estimates are that the European Union could get 15% of its power from marine sources. But ocean energy is currently expensive and there are significant technical challenges still to be overcome.

The world’s largest tidal power device will soon begin testing off the coast of Scotland. The 680-ton, 240-foot-long, airplane-shaped device will be connected to the European Marine Energy Center for testing.

The device, built by the Scottish company Orbital Marine Power, is designed to produce 2 megawatts of electricity, enough to power 2,000 homes. It has a pair of 52-foot-long turbines attached to two wings.

Compared to wind and solar power, the marine energy sector has been much slower to develop because of the many difficulties of working in harsh marine environments as well as the technical challenges associated with harnessing power from waves and tides. But ocean waves and tidal movements hold enormous amounts of energy and have the advantage that they are available at all times, unlike wind and solar energy, which are variable in nature.

Experts say that the future of tidal energy lies with arrays of floating or sea-bottom-mounted turbines that capture the energy of tidal currents in unobstructed waters. There are various places around the world where this is an attractive opportunity, most notably in Nova Scotia’s Bay of Fundy, where the world’s most extreme tides – rising and falling more than 50 feet – contain vast amounts of power.

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The World’s Largest Tidal Power Device Will Soon Begin Testing Off Scotland

Photo, posted May 18, 2017, courtesy of Chris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Air Pollution With Plants | Earth Wise

January 15, 2020 By EarthWise Leave a Comment

New research by Ohio State University suggests that adding plants and trees to the landscapes near factories and other pollution sources could reduce air pollution by an average of 27%. In addition, the study indicates that, in many cases, plants may be a cheaper option for cleaning the air than more technological approaches.

The study looked at public data on air pollution and vegetation on a county-by-county basis across the lower 48 states. It then calculated what adding additional trees and plants might cost. The calculations included the capacity of current vegetation to mitigate air pollution as well as the effects that restorative planting might have on pollution levels.

In 75% of the counties analyzed, it was cheaper to use plants to mitigate air pollution rather than add technological interventions such as smokestack scrubbers to the sources of pollution. The results varied according to the pollution source. For example, technology is cheaper at cleaning the air near industrial boilers than ecosystem approaches. For the broad manufacturing industry, one approach or the other was favorable, depending on the type of factory.

Adding trees or other plants generally can lower air pollution levels in both urban and rural areas, although success rates depend on a variety of factors including how much land is available to grow new plants and current air quality.

Reducing air pollution is critical to public health. An estimated 4 in 10 people in the U.S. live in areas with poor air quality, leading to health issues including asthma, lung cancer, and heart disease. The study shows that nature should be part of the planning process for industry to deal with air pollution.

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Nature might be better than tech at reducing air pollution

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.