Final answer:
Shale gas contributes significantly to the U.S. natural gas supply, with shale resources accounting for 827 Tcf of the potential resources. The extraction of shale gas has become more economical, highlighting its role in electricity production, heating, and industrial uses. The associated environmental impacts, such as methane emissions, are also a concern.
Step-by-step explanation:
The percentage of natural gas currently recovered from shale wells is significant given the advances in extraction technologies, such as hydraulic fracturing (fracking). Shale resources account for 827 trillion cubic feet (Tcf) out of a total of 2,552 Tcf of potential natural gas resources in the United States. While the exact current percentage of natural gas from shale wells is not directly stated in the information provided, it can be understood that it's a large portion of the U.S. natural gas supply, especially since the advent of fracking has made it more economical to extract this gas. Moreover, the U.S. consumption rate of about 22.8 Tcf per year suggests that shale could be a significant contributor to meeting this demand.
Natural gas constitutes 31% of energy consumption in the U.S., out of which a considerable amount is used for electricity production (35%), industrial purposes, and residential and commercial heating. The importance of finding effective and environmentally sensitive methods to capture and transport these resources is underscored by the fact that methane emissions from the production and transportation processes contribute notably to greenhouse gas emissions.