The Relationship between Household Energy Consumption and Greenhouse Gases

Monterey Coast
The effects of Climate Change on quality of life can start small but quickly evolve into something that demands significant alteration to one’s life. It can be anything from air quality, drinking water quality, or living conditions. The beautiful tourist city by the bay of Monterey houses a diverse community and acres of farms that play a large role in providing fruit nationwide. Despite being such a beautiful place compared with somewhere heavily built up like Los Angeles, Monterey faces its own climate change challenges. 

Monterey’s iconic coastline and coastal ecosystem draw in millions of visitors each year. This beautiful coastline is being destroyed because of ocean acidification, warming seawater temperature, sea level rise, changes in currents, upwelling and weather patterns. All of which have had a profound effect on the beautiful marine life that makes Monterey special. As a tourist economy, Monterey County will suffer greatly as the local environment degrades. From there economic damages play out their effects in social, political, geographical, and health spheres. As part of the global effort to curb greenhouse gas emissions, Monterey can also take part in reducing its own greenhouse gas emission and specifically something easier to adapt/improve than transportation; household energy consumption and GHG emissions.  

Household carbon emissions have been popularly broadcasted and advertised in incentivizing reduced usage and promoting greener technology. However, there really isn’t any information about what household activities produce which types of greenhouse gases, how long it stays in the atmosphere, what type of greenhouse gas have what kind of effect. And what it means to understand the true cost of household energy consumption and how more awareness of this indirect topic could lead to further changes. I believe a household energy consumption and greenhouse gas emissions should include an individual’s choice of transportation, diet, material consumption, and household activity (e.g. Energy efficient appliances, habits, etc). I guess to describe it more broadly it’s an inspection of the cradle to grave process of all-natural resource and its byproduct from our lifestyle that I’d like to call household energy consumption.  By tracing our energy production to the source, we can gain awareness of our energy consumption and begin to adjust our lifestyles and action in a way that positively impacts the environment.  

One of the largest contributors to climate change is greenhouses gas emissions, which greatly alters the atmospheric processes and can affect the physical land and the health of many. Greenhouse gas emissions trap heat and make the entire earth warmer. The major greenhouse gases are carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), and Fluorinated gases (F-group gases). The figure below demonstrates the total U.S. greenhouse gas emissions broken down by economic sector from highest emission to lowest and the categories are transportation, electricity, industry, commercial & residential, and agriculture (Fig. 1). Keep in mind that in 2017, U.S. greenhouse gas emission decreased by 0.5 percent from the previous year. A piece of very good news is that 2017 greenhouse gas emission was 13 percent below 2005 levels. The influencing factor mainly came from the increased use of renewables in the electric power sector, warm weather which reduced the use of air conditioning, and a shift from coal to natural gas (EPA, 2019).  

Figure 1. Pie chart provided by Environmental Protection Agency 2018

U.S. households use energy to power many home devices and equipment, but more than half of a household’s energy consumption are for space heating and air conditioning. Electricity and natural gas are the most used energy sources in homes. Electricity accounted for 44% of household energy consumption in 2017 while natural gas accounted for 43% of residential sector energy. The next most consumed energy source is petroleum – in the form of fuel oil, kerosene, and propane (EIA, 2018). 

Household energy consumption is the third largest use of energy in the US. However, 65% of that energy is used and about 35% of that energy is wasted. The figure below demonstrates the ten energy users and the proportion of their energy usage in homes (Fig. 2). The top ten energy users are: cooling & heating (47%), computer (1%), dishwasher (2%), TV/DVD/cable box (3%), electric oven (3-4%), refrigerator (4%), washer & dryer (13%), lighting 12%), and water heater (14%) (Campbell, 2018). 


 Figure 2. Pie chart created by Uma Campbell
While the number of GHG emissions from residential sectors has decreased despite the number of households increasing, household energy consumption does still contribute to global greenhouse gasses. And if we compare carbon dioxide per capita between different countries, the United States ranked the highest even though having less population in comparison to China and India.  

According to the EPA, approximately 62.9% of electricity generated in the U.S. comes from burning fossil fuels, mostly coal and natural gas. The 11.6% of 2017’s GHG for the commercial and residential sector mostly accounted for burning fossil fuel and handling waste (EPA, 2018). Below is an overview of U.S. 2017 greenhouse gas emissions. Household energy consumption has an indirect connection to the production of nitrous oxide, methane, and fluorinated gases through transportation of fossil fuel and natural gas, waste management, energy distribution, and personal lifestyle.  
Pie chart that shows different types of gases. 82% from carbon dioxide fossil fuel use, deforestation, decay of biomass, etc., 10% from methane, 6% from nitrous oxide and 3% from fluorinated gases.


Indirectly, households also contribute to methane in the atmosphere through the production and transport of coal, natural gas, and oil, on its way to being burned for electricity and the byproduct of carbon dioxide. The indirect relationship to nitrous oxide is the combustion of fossil fuel and solid waste, and treatment of wastewater. Whereas fluorinated gases are not from natural sources and only comes from manmade processes such as fluorinated gas production, nitrous oxide supply, aluminum production, electronics manufacturing, magnesium production, electrical equipment manufacturing and refurbishment, electrical transmission and distribution equipment use, and importers and exporters of such gases. Both gases of which all households have an influence on by material consumption and lifestyle choices. There is a link between the household energy consumption and greenhouse gas emission, most commonly highlighted as carbon dioxide, however the other GHG are also indirectly produced. There is insufficient research compilation into that connection so it’s hard to say to what extent do household energy consumption produces different types of greenhouse gases. 

The effect each gas has on climate change depends on three factors: concentration/abundance, duration in the atmosphere, and impact. A categorical label has been calculated for each gas in reflection of its duration, impact, and concentration, the label of Global Warming Potential (GWP). The higher GWP the more energy absorption per pound and the higher contribution to warming the earth versus gases with lower GWP (EPA, 2018). 

To get an idea of the interactive dynamic of duration, impact, and concentration of these greenhouse gases, we will be looking at global warming potential of greenhouse gases over 100-year timescale (Fig. 3). Global warming potential scale is measured in relative to the warming impact of one-unit mass of a greenhouse gas relative to carbon dioxide. A GWP100 of 5 therefore means that one ton of HFC has five times the warming impact of one ton of carbon dioxide over a 100-year timescale (OurWorldInData, 2018). 




As shown above, the F-group gases have 23,500 times more warming potential than carbon dioxide. The average life span for these gases are: Methane: 12.4 years, Nitrous oxide 121 years, F-group gases: few weeks to thousands of years, and Carbon dioxide: varies as the gas is redistributed rather than destroyed over time (EPA, 2019).

Over the recent decade, carbon dioxide has been under such heavy investigative light on its contribution to climate change, I feel that it’s important that people also understand that every aspect of their lives and their household contributes directly or indirectly to the greenhouse gas emission – and by proxy climate change. These lesser emitted gases, F-group, nitrous oxide, and methane may not show as much of a significant effect on climate change as carbon dioxide does but over the long-term scale it poses a significant threat. It is important, however to take note of these gases effect on the environment. Methane has the same effect as carbon dioxide where it thickens up the atmosphere, creating a greenhouse effect, however with a GWP 28, it means that methane has 28 times the effect of carbon dioxide. Nitrous oxide with a similar effect as carbon oxide but has an additional effect, it damages the ozone layer that is protecting us from UV. And F-group gases also damages the ozone layer but have 23,000 times more potential than carbon dioxide. The figure below is a concept map that I have created to visualize the emissions from household energy consumption. 



Coming back to household energy consumption and greenhouse gas emission, there are different ways to look at it; either through life cycle assessment or annual consumption. U.S. households contribute greenhouse gas primarily through carbon and human behavior also have a major influence on that emission. With a small activity in new housing development, the older homes have lesser energy and heat efficiency, thus requiring more energy consumption and greenhouse gas emission. Throughout the country and even locally here in Monterey and its neighbor, Santa Cruz, there are inititative programs that strive to make a difference by updating home appliances for free while collecting valuable data on home energy efficiency and percentage of efficient energy users across counties. 

I believe that there are connections there to associate one's household activity and lifestyle to the increase of greenhouse gas emissions. Besides that point, there is benefit to raise awareness of the lifespan of these greenhouse gases and the global warming potential. All of this was relatively new information for me, even as an environmental studies major, and this information should public knowledge to educate more people. By providing more awareness and education, people will be more equipped to make the right decision within their economic and financial situation with respect to the environment.

Below I will attach links to more information.
Greenhouse gas emissions:


F-group Gases:

How to reduce household energy consumption:



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