Geothermal energy is considered environmentally friendly than fossil fuel sources, and geothermal power plants are expected to have a low carbon footprint. It is renewable that can last million years. There exist, however, several gases stored under the earth’s surface which are released into the atmosphere during digging (TWI 2020). This research paper aims at monitoring the potential positive and negative effects of geothermal on environmental quality (CO2 emissions) in the USA for the period January 1980 to August 2019. The paper employed wavelet and partial wavelet coherence computations to explore the impacts of geothermal energy usage on the environment. The concluding remarks from the estimations can be classified into short-term (1–3-year cycle) results and long-term (3–8-year cycle) results. It is found in the short term that (i) geothermal usage increased CO2 emissions during 1980–1983 and 1993–1997 and (ii) CO2 emissions caused geothermal usage to increase for the period 2000–2009 and after 2015. The paper reveals also that in the long term, (a) geothermal energy consumption increased CO2 emissions during the periods 1985–1990, 1993–1996, and 2013–2016 and (b) geothermal energy consumption decreased CO2 emissions for the period 1996–2008 in the USA. This research work eventually yields some relevant geothermal energy policy suggestions for US policymakers to make geothermal more environmentally friendly.