Battery Backed Charging
Whitepaper
Reliability
Today, Electric Era is releasing a technical white paper that shows, in detail, for the first time, our approach to achieving ideal design outcomes for car refill retailers using optimal grid and battery sizing for EV fast charging stations.
Four years ago, Electric Era launched on the premise that battery-backed EV fast charging would offer superior economics, faster time to market, and improved reliability for EV charging station owners over legacy EV fast charging solutions. With Electric Era charging stations installed coast-to-coast and dozens more in development, we have proven that storage assisted charging is the superior approach to light-duty EV fast charging.
In sharing this technical white paper, we aim to accelerate the EV charging industry, and share knowledge with utilities as they modernize the grid. We invite feedback from industry on the approach and hope you will leave your thoughts and questions in the comments section below. We would love to hear from you!
For additional context, I lay out the background and benefits of battery-backed charging, alternative approaches, and a conceptual comparison of the various approaches; however the technical white paper is linked below so feel free to jump to the end if you prefer. Enjoy!
Deploying EV fast charging is notoriously challenging; a single station can consume the equivalent of 1,000 homes of power in one city block, making power access extremely expensive and time-consuming.
Traditionally, EV charging companies install large pad-mounted transformers that are sized for the peak expected power consumption of the station. In the past, if you had a station with four 200kW chargers, you would install 800kW of transformer power capacity. Some companies, like Tesla, have taken advantage of intermittent charging power levels to "rightsize" the power capacity and downsize the station's transformer.
Electric Era took the next logical step by adding affordable energy storage to our stations. Over the last four years, we have developed patents, technologies, tools, and software to enable this approach to leverage pole-mounted transformers, which are easier to secure, more affordable, and have a smaller footprint.
Our battery-backed charging stations are installed across the country. At the time of this writing we have dispensed 91 MWh of energy during 3739 EV charging sessions with greater than 99.5% uptime and perfect demand peak power shaving with the battery. The results speak for themselves: battery-backed EV fast charging is the future.
There are three approaches to using energy storage (batteries) in EV charging: battery-integrated, temporary storage, and battery-backed EV charging.
Battery-integrated chargers (Figure 1) put the grid in series with their battery. Due to the serial grid connection, battery-integrated EV chargers hit energy limits long before they hit port availability limits and run out of energy. This leads to a poor driver experience, long wait times, and under-utilized stations. High station costs often lead to a poor return on investment, given that the cost to increase charger utilization is the cost of adding new charging units.
Figure 1: Battery integrated charging
Temporary power solutions (Figure 2) can bring EV charging quickly to a site on a skid or in a shipping container using mobile energy storage and gas generators. While temporary solutions allow station owners to secure power quickly, they are loud and suboptimal in appearance. This leaves retailers settling for an awkward brand interaction and leaves EV drivers with anxiety, wondering if this station will be a reliable stop or only temporary due to its appearance.
Gas generators can require challenging permits due to emission standards, which can delay implementation timelines. They also come with high energy costs given the fuel conversion inefficiencies and more volatile cost of natural gas, making the approach economically unsustainable.
Finally, temporary solutions do not allow station owners to capture the long-term benefits of demand charge reduction and grid outage resilience once replaced with a legacy charging solution. High grid upgrade costs are eventually incurred by the station owner.
Figure 2: Temporary power EV charging
Battery-backed EV charging (Figure 3) combines grid power with battery power, which allows it to increase energy throughput and supportable session count while decreasing power capacity and demand charge requirements. The approach combines smaller transformers that are easier to secure with affordable energy storage.
Like temporary solutions, battery-backed charging stations can be quickly deployed in as little as 4 months; however, permanent solutions allow retailers to protect the driver experience, improve brand perception, and benefit from long-term demand charge reduction and grid outage resilience.
Figure 3: Battery-backed EV charging
As shown in Figure 4, battery-backed EV fast charging represents a goldilocks zone for station owners by combining the merits of faster deployment, long-term benefits of storage ownership, a superior driver and brand experience, and low costs.
Battery-backed charging stations like ours at Electric Era provide a lower total cost of ownership and come with low upfront costs. In a power time crunch? No worries. With a little bit of planning, we have installed our EV Charging stations in as little as 4 months.
Figure 4: Conceptual comparison of EV charging approaches
Most importantly, our approach has been proven to protect the driver experience and retailer brand perception while providing long-term benefits to station owners such as demand charge reduction, grid outage resilience, and enhanced charging session reliability.
Reach out today to our team of electric vehicle charging experts to get ahead and ensure a seamless transition for your car refill solutions.
Onwards,
Quincy Edmund Lee
CEO and Founder of Electric Era