S. Brauer, C. Brumlik
Nanobiz LLC,
United States
Keywords: BESS battery EV charger safety charging non-lithium
Summary:
Aggressive goals for emissions reduction and EV charging are not being met. New business models are needed to provide economic incentives for firms outside the utility industry to invest in storage and potentially renewable generation. The advantages of distributed storage are clear: 1) Increased resilience 2) Increased efficiency: fewer AC/DC conversions at large scale 3) More efficient integration of solar generation- fewer AC/DC conversions 4) Less congestion-avoided transmission and distribution (T&D) construction CommunityBattery won Phase I proposals from the Connecticut IES (Innovative Energy Solutions) Program that can serve as a model for states needing to increase storage to meet emissions goals and to improve the economics of both existing generation and the integration of renewables. By powering a fast EV charger (level 3) with a BESS (battery energy storage system) rather than a direct line to the grid per NEVI program requirements, the economics of both EV charger and BESS installations are improved. In addition to the ability to time shift demand, infrastructure costs and installation times are dramatically improved. Furthermore, the BESS can provide grid ancillary services if not being used to power a charger. Installations of BESS at the commercial and industrial (C&I) level can happen on a much faster time scale than utility scale storage which has to contend with a 5 year plus interconnection queue. Level 3 EV chargers are only used ~20% of the day and at best, are forecast to increase to 30%. These chargers require 480 V lines which are expensive to install and can incur utility use charges. Unfortunately, these lines are idle ~80% of the time, which is a very inefficient use of resources. Utilizing a BESS instead provides numerous benefits. For smaller size BESS which can power a single charger, this allows faster EV charging rates during peak demand hours while only requiring a 208-240V line with 200 ampere capacity. This line from the utility provides 40-48 kW that can charge a 400-500 kWh BESS in 10-15 hours. By using the BESS, overall charging rates can be boosted to 75-150 kW at peak demand times. For larger BESS of several MWh, several EV chargers can be powered at levels comparable to NEVI chargers of 250-350 kW, however, this does require a larger line from the utility. Additional benefits include resiliency in case of emergency since this BESS would have sufficient capacity to power stores and to charge emergency vehicles. Since businesses rather than utilities may be the customers here, a much wider suite of technologies can be considered. Safety and environmental justice concerns preclude siting large scale lithium ion batteries near residential neighborhoods or fueling stations. Given the flammability risk and environmental hazard, much safer battery chemistries are preferred. We will explore one or two such chemistries that have been demonstrated at grid scale.