Methane emissions from US landfills equal 14% of US residential natural gas consumption, and represent a significant waste of energy. This work presents and analyzes three concepts for landfill gas (LFG) utilization, which impact the water, electricity and food sectors. The first novel concept uses LFG to power refrigeration cycles to enable atmospheric water harvesting (AWH). Freshwater produced by LFG-based AWH can be used for water intensive operations (drilling, hydraulic fracturing) in oilfields located near landfills. The second concept is about routing LFG to nearby natural gas-fired power plants, instead of using it for onsite electricity generation. This approach is attractive, since both landfills and power plants are concentrated around population centers. The third novel concept uses LFG as the feedstock and energy source for ammonia production, which is the starting point for fertilizers. A framework and methodology for quantifying the benefits of these concepts is established. Emissions from landfills in Texas are analyzed to map the current LFG management, and quantify the benefits of the proposed concepts. Firstly, LFG-based AWH can meet 14% of the water requirement of the Barnett Shale, which can be served by 20 landfills. Secondly, routing the LFG to gas-fired power plants will enable a 3% increase in statewide installed capacity. Importantly, five power plants can increase their capacity by more than 10%. Thirdly, LFG can be used to produce 3,200 tons of ammonia daily, which yields enough fertilizer to cultivate nine times the current area under corn cultivation. Overall, these concepts offer alternatives to LFG-based onsite electricity generation, which enables utilization of only 22% of the generated LFG. The proposed waste-to-value concepts can be extended to other regions and offer options to augment water, electricity and food production globally.

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