Can we avoid rolling blackouts in extreme weather?

Cold snaps. They’re bound to happen in Tennessee, and the last two winters saw unusual deep freezes. After the most recent cold snap here in Nashville, The Tennessean published an article about rolling blackouts and what TVA is doing to prevent them from happening. This article highlights what E3 is doing to help reduce the risk of blackouts, and when they do happen, how homeowners can stay safe and warm in their homes.  

Think back to December 2022. Many Tennesseans lost power just days before Christmas as TVA struggled to generate enough electricity. The cold temperature demanded an increase for heat in homes and buildings, but power plants couldn’t keep up. TVA had to reduce the strain on its grid as the demand rose nearly 35% higher than a typical winter day. As a result, many local utilities were forced to cut power to residence. This intentional power outage is known as a rolling blackout. Since then, TVA has invested over $200 million in upgrades to its coal, gas, and hydro facilities and has focused on building system reliability and resiliency. 

The investments must have helped, as Tennessee avoided the blackouts during the most recent cold snap this past January. But with the increase in population and new construction on the rise in the area, could Tennessee once again reach a critical limit? 

 

How can homeowners and builders help prevent widespread outages in the future? 

Invest in energy efficiency. 

Improving the energy efficiency of homes has the potential to significantly benefit the grid during extreme weather events. Residential homes alone account for about 225 Billion square feet of living space, roughly 70% of all buildings in the country. Imagine what just a 10% efficiency improvement to homes could do!

 

What efficiency improvements make the most difference? 

Heating and Cooling Systems: Heating and cooling systems consume the most energy in homes, roughly 53% of home energy use in America. If an HVAC system is at the end of its life and needs to be replaced, E3 recommends a dual-fuel heat pump. 

A heat pump works like your refrigerator to absorb heat and “pump” it to the desired place. If it’s cold outside, heat pumps can extract heat from the outside air (yes, even in cold temperatures) and pump it indoors. The system can then reverse directions in the summer and pump the heat that accumulates indoors to the outside. 

Heat pumps operate with electricity. However, a dual-fuel heat pump has a natural gas back-up heat source that provides emergency heat when temperatures outside get too cold for the unit to efficiently extract heat. Depending on the performance of the system, the back-up heat source kicks on between 15 degrees F and 5 degrees F. A dual-fuel heat pump also helps take the strain off of the electrical grid at cold temperatures because it shifts the heating fuel from electricity to natural gas. Diversifying fuel sources is important for resiliency. If homeowners have both electricity and natural gas available at their home, a dual-fuel heat pump is a great option!

Insulation and Air Sealing: Insulating and air sealing a home not only makes a home more efficient, but it also allows the house to stay comfortable longer when heating and cooling systems go offline during power outages. A well-insulated house is said to have more thermal mass. The more thermal mass a home has, the slower the heat transfer process through the shell of the house. Additionally, a well-insulated and air sealed home requires a smaller heating and cooling system. 

Air sealing is often neglected when homeowners add insulation, as many insulation installers overlook the tedious work of air sealing. However, air sealing is just as important as the insulation! Without air sealing, hot air can move right on through cellulose or fiberglass. Read more about this topic here.

The North American Insulation Manufacture’s Association (NAIMA) estimates that 90% of homes are under-insulated. Many of the existing homes that E3 inspects have little to no insulation in the attic. Even newly constructed homes can be under-insulated. 

Most new homes In many areas of TN, homes were being built to 2009 energy code standards, which requires only R-38 in the attic and R-13 in walls, while other areas had adopted stricter energy codes, which call for R-49 in the attic and R-20 in the walls. 

Adopt Updated Code Standards: Recently, the state of Tennessee passed a mandate that made the state-level code mandatory across all jurisdictions. That means that areas such as Metro Nashville, which had adopted the 2018 energy code, are required to revert backwards to the less-efficient 2009 code. Not only does this outdated code allow for less insulation, but it also allows for draftier homes (i.e. the air leakage allowance has increased).

When homeowners purchase new homes, they think they are getting a house with the latest and greatest features, the highest efficiency “model” on the market, if you will. Similarly, when consumers buy a new car, they would never assume the new model had a lower MPGs, less safety features, and even missing parts like air bags!  

Unfortunately, new homes in TN are not as efficient as most buyers assume. 

 

How does E3's work support sustainability and resiliency?

Recently, E3 completed major renovation projects in the Green Hills and Forrest Hills neighborhoods. All of the HVAC systems in both homes were re-designed for higher efficiency and improved air quality. Insulation was added to the attic and to unfinished areas of the home, which have now become usable bonus rooms. The crawlspaces were also sealed to provide durable, dry, and clean footprints for the homes. All of these measures will help the homeowners stay warm when there is a power outage or extreme weather event, and the homeowners have done their part to make Nashville more resilient. 

To E3, the residential market is a severely underserved sector and a huge contributor to energy use, carbon emissions, and resources. Improving the efficiency of homes can significantly reduce the load on the grid during extreme weather events, thus lessoning the chance of a rolling black out. A high-performance home is insurance in comfort and durability for homeowners as well; in the face of a power outage, a high-performance home will stay livable longer than the average home when it must coast without power. 

As severe weather events become more and more common and increasingly extreme, E3 is leading the way in high-performance homes. All of the components (the insulation, ventilation, heating and cooling systems, etc.) must work together to create an integrated system. That is why all of our projects start with a Whole Home Diagnostic Assessment.

 

Are you ready to create an energy-efficient, healthy, resilient home? 

Whether you live in an existing home or are planning to build a custom home, E3 can help!

Call us today to get started.  
615-876-5479

 

 

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