2.4 Decarbonization scenarios evaluation framework

STUDY APPROACH & METHODOLOGY

2.4 Decarbonization scenarios evaluation framework

Decarbonization pathways can be evaluated against a set of criteria that enhance public welfare. These criteria include but are not limited to local and system environmental impacts (both carbon and criteria pollutants), reliability and resiliency, and affordability.53

This effort focused on fi ve specifi c key criteria (Exhibit 2.3).54

Energy system reliability and resiliency is a vital condition for a successful energy transition. As an intrinsic condition of the decarbonization scenarios modeling, reliability requirements are met for all scenarios at the same level using proxies for loss of load. System resiliency is also important. Resiliency is defi ned here as the ability of the system to avoid altogether or bounce back quickly and minimize the impact of system outages including in unforeseen events (such as extended periods of extreme weather), as well as to help improve public safety by enhancing local generation. This is enabled by distributed and local energy to provide backup on a local level with clean fuels and solar. Resiliency is dependent upon infrastructure design and thus differs across scenarios based on the assumed energy infrastructure.

Resiliency was evaluated in this effort by understanding the proportion of customers that would receive energy from both a fuels and an electric network given a fuels system’s potential ability to provide redundancy in the event of an electric outage.

Long-term solutions for decarbonization need to address the hard-to-abate sectors (e.g., industry and heavy-duty transportation); the challenges associated with decarbonizing these sectors varies across scenarios. This analysis qualitatively assesses the ability for different scenarios to meet the needs of customers in hard-to-abate sectors as they decarbonize. Solutions are deemed more challenging where they either create new complications (e.g., requiring switching from receiving fuels via pipeline to fuels via trucks) or may confi ne the options for industrial customers or vehicles to decarbonize, leading potentially to higher expense and/or other commercial challenges for these customers.

Customer conversion challenges also vary across scenarios both in the level of intervention and percustomer cost of conversion to new technologies on the customer-end, and in the number of customers that need to switch technologies.

Technical maturity is critical in assessing different scenarios. Scenarios that rely upon technologies that have not been proven at-scale (e.g., multi-day duration energy storage) may encounter unforeseen implementation challenges. Furthermore, scenarios requiring signifi cant scale up of technologies that to date have been only demonstrated at smaller scale could have more challenges than scenarios leveraging only technologies that have already experienced broad commercial deployment. While all scenarios rely to some extent on scaling of early technologies, some rely more heavily on these newer technologies.

Overall system costs (affordability) vary across scenarios. Quantitative analysis was performed as discussed in Section 2.3 to determine the cost impacts of different scenarios.

STUDY APPROACH & METHODOLOGY

Exhibit 2.3 Key criteria used to assess scenarios

KEY CRITERIA DESCRIPTION