Microgrids Needed to Bolster Grid Resiliency for Transport Electrification

This blog was coauthored by Ryan Citron.

Grid reliability is declining as weather volatility is increasing. The latest example of this trend is Hurricane Ida, which left roughly 600,000 residents in Louisiana without power for more than a week after the storm made landfall. According to Entergy Louisiana, numerous areas were expected to remain without power for at least an additional 3 weeks. As the impacts of climate change accelerate, extreme weather events like Hurricane Ida are likely to increase in quantity. This trend could be damaging to EV adoption in medium and heavy duty truck and bus markets because fleet managers and drivers could become stranded when the electric grid goes down.

Microgrids: An Emerging Solution

Although EVs can serve as assets to the grid or fulfill local power needs during outages, other distributed energy resources (DER) and energy management strategies are needed. First, market developments that would enable EVs to support grid or local power needs are limited as of mid-2021. Second, even if the market were well developed, the extent to which EVs could last as grid resiliency assets is limited. For example, most EVs would not be able to power homes and businesses for the outage lengths seen in Louisiana or in Texas earlier this year.

A solution to the growing grid reliability challenge is microgrids. These are local power systems that manage DER to overcome power outages. For fleet managers, these systems can solidify confidence of operational readiness. However, microgrids can also add capital costs and engineering complexities to an already capital intensive and complicated business decision.

In addition to the increased capital required for EVs and charging equipment, many fleet managers must also reconsider vehicle infrastructure and enter/exit rights to facilities. EV charging takes longer than petroleum refueling. Also, where a fleet once consolidated energy infrastructure to a few pumps, it will likely need to distribute infrastructure to many more charging stations with electricity. Therefore, for microgrids to become feasible, fleet operators must meet their reasonable demands for capital and space.

Low Cost, High Power Options Are Needed

Reducing microgrid capital cost requirements can be achieved by repurposing microgrid DER for revenue-generating grid services when the grid is running. Here, an energy service provider would manage the DER assets of the microgrid for both grid services and local energy reliability demands. Overall system costs would be reduced via the grid services, and capital costs would be avoided through as a service pricing. Enchanted Rock’s development of this model has resulted in the development of 215 distributed generation sites as of early September 2021.

However, for such systems to be attractive, asset power density must be high. Assets need to meet grid market regulatory thresholds or comply with interconnection requirements that are often burdensome for small capacity assets, or both. Additionally, fleet facilities have space limitations. Historically, such power densities have been found in diesel generators, which are anathema to the goals of fleet electrification.

An alternative is natural gas generators. From a climate and local air quality perspective, this is an improvement over diesel. However, the improvement can be significantly magnified if instead of using fossil-based natural gas, generators consume renewable natural gas produced from dairy farms, wastewater treatment plants, and so on. As shown in lifecycle analysis used in the California Low Carbon Fuel Standard, these feedstocks have highly attractive attributes for climate objectives. Learn more about the potential of using microgrids to overcome the significant challenges faced by EV fleet managers, fast charging site operators, and utilities in Guidehouse Insights’ new white paper, Powering Resilient EV Infrastructure, commissioned by Enchanted Rock.