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  • Writer's pictureAlison Brown

Overview of Electric Vehicle Charging

Part 1: Hardware

Many people don’t realize that the the first small scale electric cars were made all the way back in 1830! However, by the mid 1930’s they were abandoned for the most part. Now, almost 100 years later, new players like Tesla have rejuvenated the EV market. Picking up off the hybrid trend popularized by the Prius, a period of high gas prices, and a growing awareness of the environment, EVs have disrupted the car manufacturing market, forcing the public to accept an alternative to the gas standard. The ultimate goal of EV’s is to create a cleaner, more sustainable transport infrastructure, but to have a significant impact, scale is key.

Roughly 20% of all US emissions come from personal vehicles[1]. With EV’s representing only 0.22% [ChargePoint 2016 report] of the personal vehicle fleet in the US, there is clear room for improvement. However, for EV’s to hold a significant portion of the market, three things must be true and stay true. EV’s must: (1) have public appeal, (2) be cost competitive, and (3) have the infrastructure to accommodate the charging of large fleets in reasonable time periods. (1) & (2) have seen substantial progress over the last few years, but (3), charging infrastructure, is just beginning to ramp up on a large scale.

Before we dive in, some fundamentals in EV charging are necessary. EV’s are currently charged through either an AC charger or a DC charger. Car batteries run on DC, so AC chargers commonly utilize an inverter internal to the EV, while DC chargers will have a separate inverter specific to the charger to convert the electricity from the grid. For this reason, AC chargers are much more limited in their ability to charge at higher speeds. There are multiple levels (speeds) and standards (connection hardware) associated with these. The levels may vary by location. See Table 1 for a summary of the charger levels and standards.

Standards are important because chargers will only work if the charging standard of the charger matches the charging standard of the car. Generally, car manufacturers have chosen their charging standard according to the region. You cannot charge across different standards – it would be like trying to plug an American plug into a European outlet. Charging levels matter because they dictate the rate of charge. So when charging manufacturers look to develop a charger, they have to decide which standard(s) and which level(s) make the most sense for them to produce.

Table 1: Charging levels and standards.

As seen in Table 1, there are currently 3 major standards in the DC fast charging market apart from Tesla, each associated with a region: CCS (North America and Europe), CHAdeMO (Japan), and GB/T (China). In late 2016, automaker powerhouses, BMW, Daimler, Ford, and the Volkswagen Group with Audi and Porsche, declared a joint venture to deploy 400 ultra-fast (350kW) CCS charging stations in Europe. While Europe joining America’s standard would seem to imply that CCS has won the battle for the fast charging standard of choice, China has the largest and fastest growing EV fleet in the world, so GB/T cannot be ruled out just yet.

Most charging manufacturers exist as more than just charging manufacturers. The spectrum ranges from large electrical companies like ABB who have a branch producing chargers, to specialized vertically integrated EV charging companies like ChargePoint, who handles everything from manufacturing to charging services and more. In general, however, charging manufacturers will offer a range of products to support the needs of various types of customers. Residential options include level 1 and level 2 chargers, while public charging stations require faster charge times and thus a level 3 charger. Manufacturers will also usually offer different variations of chargers to support different options for charging standards. Only ABB offers multiple standards and levels in a single charger.

Global EV Outlook 2017 reports that despite massive public charge station growth in 2016, there are only 212,000 public slow charger outlets and 110,000 public fast charger outlets for the 2 million EV’s in the world. That is a ratio of more than 6:1 EV to public outlets, implying that most EV owners are using private chargers. Inevitably, a successful solution will have a combination of residential, private/business, and public charger options, but I believe the most important component for large scale public adoption is a significant ultrafast charging infrastructure (>200kW). These could become synonymous with our current gas stations and relieve users (or autonomous cars) of the stress associated with long charge times and unavailability of charge stations. A future of large scale public charge stations means that a universal standard, agreed upon across car manufacturers and charger manufacturers, would be the most efficient path forward. However, a universal solution is likely years down the line, and in the meantime, the battle for charging standard will persist.

We must also consider the fact that to accommodate such a charging infrastructure, a corresponding electrical infrastructure upgrade will be required. Many charger manufacturers and software providers have created a workaround to inadequate infrastructure through demand management, basically allowing manual or automated setting of charge rates. By allowing a lower charge rate, property owners can increase the maximum number of operating chargers. However, this means that any time the number of people charging crosses a certain threshold, the chargers will not be acting at their nameplate capacity. Ideally, infrastructure would be upgraded to allow for charging of large fleets at full capacity, recognizing the full potential of EV’s.

On a forward looking note, it can be fun and useful to envision the future technologies of charging infrastructure. Some things we have started to see or can hope to see are induction chargers and portable chargers. Induction chargers aren’t a serious competitor at the moment, but ABB recently introduced a fast charging induction charger for public transportation that would be installed at select bus stops to quickly replenish the bus along its route. Portable chargers are another solution to the same problem. Instead of creating new lots for the charging of large EV’s, people are envisioning new ways to bring the charging to the vehicle. An exciting version of this would be drone delivered charging, where the vehicles would never even have to stop their route! Amazon has already been granted a patent for a roving drone that would charge personal EV’s as you drive. Of course for all of this to matter, EV’s still need to beat out hydrogen cars for the title of the preferred alternative to gas vehicles.

Part 2 - Software

As we covered,  more drivers are purchasing Electric Vehicles (EVs) over conventional gasoline and diesel powered cars.   Accordingly, a market has developed around the supply and installation of the charging station hardware.   With only 300,000 EV’s on the road, the market is still small, but it is rapidly growing.  There has been a 3000% rise in EVs since 2011! [Elkind, Ethan, 2017] To further increase their sales, some automakers are now partnering with charging service companies to provide a comprehensive service offering to their customers.

As charging station hardware has developed, so too have the business models for public charging stations.   Public EV charging stations fall into three primary categories: (1) non-network, pay as you go, (2) networked, subscription based, and (3) free [Berman, Brad, 2014]. Companies who provide networked charging stations advertise the following benefits:

  1. If a driver is part of a network he/she will have a membership which dictates the price of charging.  This can benefit drivers with discounted rates compared to out-of-network drivers.

  2. Network stations are easy to find.  The network providers maintain databases and maps of the stations which allows the EV driver to find the closest available station instead of driving around to find an open charging station. A non-networked charger is not part of any connected map; it is a stand alone piece of equipment and cannot transmit or receive information.

  3. Network stations have remote support for EV drivers. Support agents can remotely unlock a charging station and also monitor and maintain the stations. This cannot be done for non-networked charging stations where a technician has to troubleshoot problems in-person.

  4. When a driver is part of a network of chargers, they are able to join a waitlist when there is a demand for charging. The charger hosts track the use of individual chargers and prevent drivers from monopolizing chargers.  Non-networked chargers do not have similar systems in place, so, except by increasing the hourly rates to charge, they are limited in their ability to control wait times.

The amount of time required for full charge is a critical feature for an EV owner in their selection of charging infrastructure.  This rate is determined by the electric vehicle and the charging station technology.   Charging stations fall into three categories:

  1. Level 1 is the standard wall outlet. It is the slowest charge level requiring 8-15 hours to fully charge a vehicle.  Due to the slow rate of charge, these are rarely installed in public.

  2. Level 2 is the typical EV plug that homeowners frequently install in their garage. Many public charging stations are Level 2 chargers. 3-8 hours are required to fully charge a vehicle.

  3. Level 3 (DC fast charge) – These charging stations are the quickest means to recharge a vehicle. It takes typically 20 mins to 1 hour to fully charge a vehicle. An example for this would be the Tesla supercharger.

ChargePoint and EVgo are two of the larger EV Charging Station Networks.  Both are comprised of Level 2 and Level 3 chargers. [Berman, Brad, 2014]  ChargePoint owns chargers at both residential and commercial properties.   Their network includes a proprietary energy management software, a mobile app, full installation services and ongoing maintenance.  They have partnered with companies throughout the supply chain including hardware manufacturers such as Eaton and Schneider, automakers such as BMW and Nissan, resellers, local installation and maintenance partners.   

EVgo is another “full service” company. They too design, manufacture and support the technology for their charging stations, but they primarily deploy Level 3 chargers for businesses.  This has made them have the largest network of public Level 3 chargers in the nation [Ayre, James, 2017]. EVgo has also become competitive by offering BMW and Nissan EV drivers charging incentives for being a part of the EVgo charging network.

Currently, “full service” companies are dominating the market, but the electric vehicle industry is still in its infancy. As the demand for EVs continues to grow, and EV’s become mainstream, there will be new technical, financial and policy-based innovations that will shape the market.   

Part 3: Utilities

In the last two Parts, we reviewed the different types of charging station hardware, and service providers.  The third critical player in charging station development is the electric utility.  Some utilities are advocating for EVs since they see the possibility of stealing market share from gasoline and diesel suppliers and want to be proactive in defining the grid-interface.  On top of that, EVs are a great way for utilities to green their image, since EVs frequently appeal to a similar segment of customers who otherwise may defect from the grid.  

Los Angeles has two primary electric utilities: Southern California Edison (SCE) an investor-owned utility and Los Angeles Department of Water and Power (LADWP) our municipal utility.  The former has a relatively forward thinking “Transportation Electrification” program, while the latter provides a simple rebate as part of their Charge Up LA! program.

SCE offers a number of different programs to their business and residential customers encouraging the installation of EV charging.  For anyone interested in EVs, the SCE website is a great reference with summaries of rebates, installation FAQs, and even sample workplace surveys to help business owners assess the value of installing EV chargers.  Ultimately, they control the EV charging through their time-of-use (TOU) rates.  This means that the cost of energy varies throughout the day and encourages off-peak EV charging.  TOU rates are frequently looked upon as the first, critical step to monetizing grid services.  Creating a market for grid services such as demand response, voltage regulation, and peak shaving, allows for innovative business models that make EVs and other technologies valuable.

LADWP’s program is far simpler and less comprehensive than SCE’s.  It offers a rebate (~$4000/charger) for residential and commercial charger installation.  The rebate application requires technical documentation that emphasizes product selection and quality of installation.   While this helps consumers make the jump to EVs, the structure of the program does little to enhance integration of the vehicles to the grid.

While LADWP and SCE’s programs are fairly different, there is one thing in common – the application process is tedious, requires professional support and understanding of a lot of fine print.  This provides great opportunities for businesses like us, but makes it frustrating for consumers.  

As more vehicles connect to the electric grid, forward-thinking electric utilities will see their potential value.  Among many other grid services, electric vehicles could minimize the impact of renewable intermittency, improve grid resiliency and provide demand response services, but this will only happen at scale if there is monetary value associated with each service.  SCE is conducting a number of pilot programs to evaluate different models for “Transportation Electrification.”  There are also many startups clamoring with new technologies to ease the problem. We look forward to seeing how new hardware, innovative software and forward thinking utilities integrate EVs into our electric grids!  


Elkind, Ethan. “California Needs More Electric Vehicle Charging Stations to Keep Pace with Demand.” The Berkeley Blog, 25 Sept. 2017,

Ayre, James. EVgo Opens Its 1,000th DC Fast-Charging Station In US. 6 Dec. 2017,

Berman, Brad. “The Ultimate Guide to Electric Car Charging Networks.”, 8 Jan. 2014,


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