New study lays out the impact of residential energy use

A new study published recently in the Proceedings of the National Academy of Sciences, “The Carbon Footprint of Household Energy Use in the United States,” took a much-needed, comprehensive look at the greenhouse (GHG) emissions related to residential energy use. Looking at data from 93 million households, the authors of the study determined that residential energy use accounts for approximately 20% of greenhouse gas emissions in the United States. The authors also sought to “clarify the respective influence of climate, affluence, energy infrastructure, urban form, and building attributes (age, housing type, heating fuel) in driving these emissions.”

The study notes that the residential sector will not be able to achieve targets set by the Paris Agreement 2050 through decarbonizing electricity production alone; behavioral changes will need to occur with regard to housing preferences as well. Meaning we need to decarbonize both on the production and consumption side to reach emissions reduction goals.

Here are some key takeaways from the study:
* GHGs are lowest in Western U.S. states and highest in Central states
* Wealthier Americans have per capita footprints of approximately 25% higher than those of lower-income residents (primarily due to having larger homes, with taller ceilings and increased floorspace)
* In especially affluent suburbs, GHGs can be 15 times higher than nearby neighborhoods

The authors assert that, if the electrical grid is decarbonized (meaning switching from coal to natural gas; increasing the use of renewables, such as solar PV, solar hot water and energy storage; and using more cogeneration*), the residential housing sector can meet the 28% emission reduction target for 2025 under the Paris Agreement. However, they note that “grid decarbonization will be insufficient to meet the 80% emissions reduction target for 2050 due to a growing housing stock and continued use of fossil fuels (natural gas, propane, and fuel oil) in homes.”

In short, meeting the 2050 target will require extensive energy retrofits and the transition to distributed low-carbon energy sources, as well as reducing the floorspace of homes and adjusting zoning to allow for denser settlement.

The study was really a wake-up call for us – this is the first time we’ve seen a peer-reviewed study that shifts the focus primarily from the power producers to a more equitable distribution of “blame” – for lack of a better word – to those who write building energy codes, community planners, community and home designers, and us, the homebuyers and end-users of electricity.

The coronavirus pandemic has forced us to take a closer look at our energy consumption, with the spring stay-at-home orders and more people working from and/or simply staying home much of the time. Various studies are showing an increase in residential energy use since mid-March of around 7-8%, depending on location/climate; those numbers came before the full blast of summer heat caused Americans across the country to fully fire up their air conditioning. Locally, our team and our customers are (anecdotally) reporting bills that are 25-50% higher over last year. My own bill – with my spouse working from home and older teen children in the house full time – is around 30% higher than 2019.

If we have any hope of sufficiently addressing the threat of climate change, we’re going to need to examine all facets of how we choose to live. Reducing our carbon consumption will be key. The authors also look at equity considerations: they note that there are those who can afford to pay for energy upgrades and, for those who can’t, subsidies or carbon pricing options for low-income energy retrofits should be explored.

We believe that installing a solar PV energy system – with energy storage, if within your budget – is the most significant single action a home and/or business owner can take in offsetting their carbon footprint. According to SEIA, through the first quarter of 2020, the U.S. has more than 81.4 gigawatts of cumulative installed solar electric capacity, enough to offset more than 91 million tons of carbon dioxide emissions. We can do even better, if we ensure that existing structures are retrofitted with energy upgrades and new construction is designed with emissions considerations at the forefront.

To read the full study, “Proceedings of the National Academy of Sciences,” click here.

If you have any questions or comments, please feel free to reach out to us!

* Cogeneration is the generation of electricity and other energy jointly, especially the utilization of the steam left over from electricity generation to produce heat.