Parallel role played by tight gas resource in fulfilling United States’ Energy requirement and reducing emission profile from hydrocarbon exploration and production industry (Life cycle analysis lens)

Abstract

Tight gas has revolutionized the energy picture in North America. The US energy information agency states that the tight gas and oil in the USA has boosted the production of natural gas by around 35% in recent years. This has reduced the need for gas imports. Thousands of meters underground, tight gas trapped in microscopic pores of very dense rocks requires hydraulic fracturing to fracture the rock and releases the gas into the well, known as tight gas. Environmental impact of producing tight gas has caused concerns related to air emissions, water contamination and disposal of waste generated by the tight gas production. There are also concerns related to the possibility of methane escaping into the air during tight gas production and development of this resource class causing minor earth tremors. The advancements in the drilling technologies have recently enabled greater volume of gas to be produce from a single drilling site. This reduces the operational footprint, which is directly proportional to emission profile of tight gas resource. There is a knowledge gap in understanding of Green House Gas (GHG- CO2 equivalent) footprint of tight gas’ resource development because of lack of operational constraints in previous environmental impact assessment of this resource. The objective of this study is to add value and reduce the scientific gap with respect to understanding of tight gas’ resource development techniques, related environmental, and land impact. There remain concerns about development of tight gas related to chemical and methane release into the local water and air, seismic events because of hydraulic fracturing and waste disposal. In order to understand this phenomenon better the work establishes the tight gas production foundation by in depth understanding of 1) Features of Tight gas reservoirs; 2) Geological environment, deposition and generation of tight gas resource; 3) Field development techniques of tight gas resource including construction, production and processing. The work then uses methodology of accounting input and out parameters of cradle to grave tight gas system boundary throughout its life cycle and understands previous GHG (CO2 equivalent) number of tight gas resource development. The work does systematic analysis and summarizes the previously published life cycle analysis to understand further the potential environmental impacts of resource development of tight gas. This will help hydrocarbon exploration and production operators to optimize the operations of tight gas production by better understanding of each sub block of tight gas field development in terms of C02 numbers by using low carbon technologies thus reducing the potential impacts.