Thursday, April 2, 2015

A Solution for Mt. Everest’s Trash Problem: Convert Waste into Renewable Energy

By Amelia Schlusser, Staff Attorney
The village of Gorak Shep, where the Mt. Everest
Biogas Project hopes to construct an anaerobic
digester. Image credit: McKay Savage, 2007
Mount Everest has received a lot of press lately, largely due to the massive amounts of trash and human waste left behind by hundreds of mountain climbers each year. The world’s highest peak has become “the world’s highest garbage dump,” and as of 2014 climbers are now required to pay a $4,000 garbage deposit, which they can only recover if they carry 17.6 pounds of litter off the mountain.

According to a March 3 Reuters article on the Everest trash problem, human waste is more problematic than other mountaineering trash, because melting snow and ice washes the waste down the mountain and presents a health hazard for people who rely on water from the Everest’s glacier-fed rivers. When you consider that climbers leave behind an estimated 26,500 pounds of human waste on the mountain each year, it is clear that this waste presents a significant problem. Getting the waste off the mountain is only a partial solution, because the area’s villages have no systems in place to process and treat the raw waste they receive.

A group of concerned climbers and activists based out of Seattle have come up with a better solution—to turn the waste into a renewable energy source. The Mt. Everest Biogas Project is currently designing an anaerobic digester that will convert human waste into biogas that the Sherpas can use as a source of renewable energy.

ClimateProgress’ Emily Atkin recently interviewed Gary Porter, the project’s founder, who discussed some of the design challenges associated with constructing an anaerobic digester in the Himalayas. First, anaerobic digesters can only operate within a temperature range between 68 and 86 degrees Fahrenheit. Second, the small village that will host the project is extremely remote, and all equipment and materials must be carried up the mountain by yaks or people. To overcome these barriers, Porter’s team designed a system that will use the village’s existing solar power array and a series of batteries to heat the digester and enable it to operate in the extreme conditions of the Himalayas.

Once operational, the Mt. Everest Biogas Project will exemplify the versatility and accessibility of renewable energy on a global scale. Biogas is a particularly appealing source of energy in the developing world, because anaerobic digesters help mitigate waste disposal needs and improve sanitation while providing electricity. Biogas production can also create valuable byproducts, such as liquid fertilizer. In rural areas, micro-biogas systems help reduce deforestation by replacing wood for heating and cooking. According to a 2011 New York Times article, a home biogas system can reduce firewood consumption by 4.5 tons a year. Some developing countries have made substantial efforts to deploy small-scale biogas systems; Nepal, for example, has helped its citizens construct 300,000 biogas systems around the country (and created an estimated 13,000 jobs in doing so).

Biogas systems also provide valuable sources of renewable energy in the United States. Using anaerobic digestion, wastewater treatment plants, landfills, and agricultural facilities can convert organic waste into renewable energy. By enabling these facilities to generate electricity on-site, biogas systems can significantly reduce a site’s electricity costs. For example, the City of Gresham Wastewater Treatment Plant’s 395 kilowatt (kW) biogas-fired combined heat and power system reduces the facility’s electricity bills by around $20,000 a month, according to a report by the Energy Trust of Oregon. After witnessing the cost savings from this initial system, which was installed in 2005, the Plant decided to invest in a 420 kW solar array and a second 395 kW biogas unit. Once these projects are operational, the Plant estimates that it will save $500,000 a year in electricity costs and generate an additional $250,000 in revenue from waste haulers.

As these examples illustrate, biogas systems can provide clean, renewable energy in a number of contexts worldwide. While generating electricity from organic waste may not have the same charm as generating electricity from the sun or wind, biogas systems can run on a variety of fuel sources and thus provide an alternative resource for areas with limited solar or wind energy potential. The United States has significant biogas potential, and states should adopt policies to incentivize biogas production within their borders.

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